Random access method, device and communication system
Technical field
[0001]
This application relates to the field of communications.
Background technique
[0002]
The random access process is a very critical step in mobile communication technology.
[0003]
Figure 1 (a) is a flow chart of the existing 4-step (4-step) Contention Based Random Access (CBRA) process. As shown in Figure 1(a), in step 101, the terminal device selects the CBRA preamble (preamble), and sends the preamble through Msg 1 in the contention-based random access opportunity (RO, Random access Occasion) pre-configured by the system ; In step 102, the network device will send msg2 after receiving the preamble. As a result, the random access response (RAR, Random Access Response) authorizes the terminal device that sends the preamble a dedicated uplink PUSCH resource and allocates a temporary CRNTI to indicate the PUSCH Uplink advance; in step 103, the terminal device sends Msg3 carrying signaling or data on the PUSCH resource; in step 104, the network device sends a contention resolution signaling Msg4 for Msg3 to the terminal device.
[0004]
Fig. 1(b) is a flow chart of the existing two-step (2-step) Contention Based Random Access (CBRA) process. As shown in Figure 1(b), in step 105, the terminal device sends Msg A. Msg A contains the CBRA preamble (preamble) and the data part (payload). The terminal device sends the MsgA preamble in the competing RO. The MsgA signaling or service data is sent in the competing physical uplink shared channel (PUSCH) resources. In step 106, the network device sends MsgB after receiving MsgA, thereby sending a random access response and a contention resolution message to the terminal device.
[0005]
It should be noted that the above introduction to the technical background is only for the convenience of a clear and complete description of the technical solutions of the present application, and to facilitate the understanding of those skilled in the art. It should not be considered that the above technical solutions are well-known to those skilled in the art just because these solutions are described in the background art part of this application.
[0006]
Summary of the invention
[0007]
The network device demodulates the MsgA data through the demodulation reference signal (DMRS) sent on the physical uplink shared channel (PUSCH) resource of the MsgA data, the DMRS sequence and the index of the MsgA preamble sent by the terminal device (Index) related, the network device obtains the DMRS corresponding to the Index of the preamble according to the preamble demodulated in the random access opportunity (RO) resource.
[0008]
If multiple terminal devices select different preamble indexes in 2-step CBRA and transmit MsgA data on the same PUSCH, the network device can demodulate the MsgA data according to the DMRS corresponding to the preamble Index.
[0009]
The inventor of the present application found that when the channel condition is poor or multiple terminal devices use the same MsgA PUSCH resource, the probability of successfully demodulating the PUSCH on the network device side is reduced, and 2-step random access is likely to fail. In this case, 2 The transmission delay and transmission efficiency of terminal equipment with -step random access will be worse than terminal equipment with 4-step random access; and, if 2-step random access fails, the terminal equipment adopts 2-step random access mode Access to the network may fail again, thereby increasing the transmission delay.
[0010]
In order to solve the foregoing technical problems, embodiments of the present application provide a random access method, device, and communication system. In the random access method of this embodiment, the terminal device initiates a non-competitive random access process or a four-step random access process when the two-step random access process is not completed. Therefore, in the case of two-step random access failure, the problem of increased transmission delay can be avoided.
[0011]
According to the first aspect of the embodiments of the present application, there is provided a random access device, which is applied to a terminal device. The device includes: a first control unit that controls the terminal device to initiate a two-step random access process; and a second control Unit, which controls the terminal device to initiate a non-competitive random access process or a four-step random access process when the two-step random access process is not completed.
[0012]
According to a second aspect of the embodiments of the present application, a random access device is provided, which is applied to a network device, and the device includes:
[0013]
The third control unit is configured to control the network device to send to the terminal device non-competitive random access configuration information for the terminal device to initiate a non-competitive random access process when the terminal device has not completed the two-step random access process, and/ Or a first instruction used to instruct the terminal device to initiate a non-competitive random access process when the two-step random access process is not completed; or, a fourth control unit, which is used to control the network device to send a command to the terminal device The terminal device initiates the four-step random access configuration information of the four-step random access process when the two-step random access process is not completed, and/or is used to instruct the terminal device when the two-step random access process is not completed The second instruction to initiate the four-step random access procedure.
[0014]
According to a third aspect of the embodiments of the present application, a communication system is provided. The communication system includes a terminal device and a network device. The terminal device includes the random access device described in the first aspect of the above-mentioned embodiment. The device includes the random access device as described in the second aspect of the foregoing embodiment.
[0015]
The beneficial effect of the embodiment of the present application is that the terminal device initiates a non-competitive random access process or a four-step random access process when the two-step random access process is not completed. Therefore, in the case of a two-step random access failure Therefore, the increase in transmission delay can be avoided.
[0016]
With reference to the following description and drawings, specific implementations of the present application are disclosed in detail, and the ways in which the principles of the present application can be adopted are indicated. It should be understood that the scope of the embodiments of the present application is not limited thereby. Within the scope of the terms of the appended claims, the implementation of the present application includes many changes, modifications and equivalents.
[0017]
Features described and/or shown for one embodiment can be used in one or more other embodiments in the same or similar manner, combined with features in other embodiments, or substituted for features in other embodiments .
[0018]
It should be emphasized that the term "comprising/comprising" when used herein refers to the existence of a feature, a whole, a step or a component, but does not exclude the existence or addition of one or more other features, a whole, a step or a component.
Description of the drawings
[0019]
The elements and features described in one drawing or one implementation of the embodiment of the present application may be combined with the elements and features shown in one or more other drawings or implementations. In addition, in the drawings, similar reference numerals indicate corresponding parts in several drawings, and may be used to indicate corresponding parts used in more than one embodiment.
[0020]
The included drawings are used to provide a further understanding of the embodiments of the present application, which constitute a part of the specification, are used to illustrate the embodiments of the present application, and together with the text description, explain the principles of the present application. Obviously, the drawings in the following description are only some embodiments of the application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the attached picture:
[0021]
Figure 1 (a) is a flow chart of the existing four-step contention-based random access process;
[0022]
Figure 1(b) is a flow chart of the existing two-step contention-based random access process;
[0023]
Figure 2 is a schematic diagram of the communication system of the present application;
[0024]
FIG. 3 is a schematic diagram of the random access method in Embodiment 1 of the present application;
[0025]
FIG. 4 is a schematic diagram of a method for a terminal device of Embodiment 1 of the present application to initiate a non-competitive random access process;
[0026]
FIG. 5 is a schematic diagram of a method for determining a preamble for non-competitive random access according to the SSB in Embodiment 1 of the present application;
[0027]
6 is a schematic diagram of a method for determining a preamble for non-contention random access according to CSI-RS in Embodiment 1 of the present application;
[0028]
FIG. 7 is a schematic diagram of the next available physical random access channel transmission opportunity in Embodiment 1 of the present application;
[0029]
FIG. 8 is a schematic diagram of a method for a terminal device of Embodiment 1 of the present application to initiate a four-step random access process;
[0030]
FIG. 9 is a schematic diagram of a method for determining a preamble for four-step random access according to the SSB in Embodiment 1 of the present application;
[0031]
FIG. 10 is a schematic diagram of a method for determining the four-step random access preamble to be sent according to the selected SSB in step 902 of Embodiment 1 of the present application;
[0032]
FIG. 11 is a schematic diagram of a random access method according to Embodiment 2 of the present application;
[0033]
FIG. 12 is a schematic diagram of a random access device according to Embodiment 3 of the present application;
[0034]
FIG. 13 is a schematic diagram of a random access device according to Embodiment 4 of the present application;
[0035]
14 is a schematic diagram of the structure of a terminal device according to Embodiment 5 of the present application;
[0036]
FIG. 15 is a schematic diagram of the structure of a network device according to Embodiment 6 of the present application.
Detailed ways
[0037]
With reference to the drawings, the foregoing and other features of this application will become apparent through the following description. In the specification and drawings, specific implementations of the application are specifically disclosed, which indicate some implementations in which the principles of the application can be adopted. It should be understood that the application is not limited to the described implementations, on the contrary, the present application The application includes all modifications, variations and equivalents falling within the scope of the appended claims. Hereinafter, various embodiments of the present application will be described with reference to the accompanying drawings. These implementation manners are only exemplary, and not a limitation of the present application.
[0038]
In the embodiments of the present application, the terms "first", "second", etc. are used to distinguish different elements from the terms, but they do not indicate the spatial arrangement or temporal order of these elements. These elements should not be used by these terms. Limited. The term "and/or" includes any and all combinations of one or more of the associated listed terms. The terms "comprising", "including", "having" and the like refer to the existence of the stated features, elements, elements or components, but do not exclude the presence or addition of one or more other features, elements, elements or components.
[0039]
In the embodiments of the present application, the singular forms "a", "the", etc. include plural forms, which should be broadly understood as "a" or "a type" rather than being limited to the meaning of "a"; in addition, the term "the" "Should be understood to include both singular and plural forms, unless the context clearly indicates otherwise. In addition, the term "based on" should be understood as "based at least in part on...", and the term "based on" should be understood as "based at least in part on..." unless the context clearly dictates otherwise.
[0040]
In the embodiments of the present application, the term "communication network" or "wireless communication network" may refer to a network that complies with any of the following communication standards, such as Long Term Evolution (LTE), and Enhanced Long Term Evolution (LTE-A, LTE- Advanced), Wideband Code Division Multiple Access (WCDMA, Wideband Code Division Multiple Access), High-Speed ​​Packet Access (HSPA, High-Speed ​​Packet Access), etc.
[0041]
Moreover, the communication between devices in the communication system can be carried out according to any stage of communication protocol, for example, it can include but not limited to the following communication protocols: 1G (generation), 2G, 2.5G, 2.75G, 3G, 4G, 4.5G and future 5G, New Radio (NR, New Radio), etc., and/or other communication protocols currently known or to be developed in the future.
[0042]
In the embodiments of the present application, the term “network device” refers to, for example, a device in a communication system that connects a terminal device to a communication network and provides services for the terminal device. Network equipment may include but is not limited to the following equipment: base station (BS, Base Station), access point (AP, Access Point), transmission reception point (TRP, Transmission Reception Point), broadcast transmitter, mobile management entity (MME, Mobile Management Entity), gateway, server, radio network controller (RNC, Radio Network Controller), base station controller (BSC, Base Station Controller), etc.
[0043]
Among them, the base station may include but is not limited to: Node B (NodeB or NB), evolved Node B (eNodeB or eNB), 5G base station (gNB), etc., and may also include remote radio head (RRH, Remote Radio Head) , Remote Radio Unit (RRU, Remote Radio Unit), relay (relay) or low-power node (such as femto, pico, etc.). And the term "base station" can include some or all of their functions, and each base station can provide communication coverage for a specific geographic area. The term "cell" may refer to a base station and/or its coverage area, depending on the context in which the term is used.
[0044]
In the embodiments of the present application, the term "user equipment" (UE, User Equipment) or "terminal equipment" (TE, Terminal Equipment), for example, refers to a device that accesses a communication network through a network device and receives network services. The terminal device may be fixed or mobile, and may also be called a mobile station (MS, Mobile Station), terminal, subscriber station (SS, Subscriber Station), access terminal (AT, Access Terminal), station, etc.
[0045]
Among them, terminal devices may include but are not limited to the following devices: cellular phones (Cellular Phone), personal digital assistants (PDAs, Personal Digital Assistant), wireless modems, wireless communication devices, handheld devices, machine-type communication devices, laptop computers, Cordless phones, smart phones, smart watches, digital cameras, etc.
[0046]
For another example, in scenarios such as the Internet of Things (IoT, Internet of Things), the terminal device can also be a machine or device that performs monitoring or measurement. For example, it can include but is not limited to: Machine Type Communication (MTC) terminals, Vehicle-mounted communication terminals, device to device (D2D, Device to Device) terminals, machine to machine (M2M, Machine to Machine) terminals, etc.
[0047]
The following uses examples to illustrate the scenarios of the embodiments of the present application, but the present application is not limited to this.
[0048]
FIG. 2 is a schematic diagram of the communication system of the present application, schematically illustrating the case of terminal equipment and network equipment as an example. As shown in FIG. 2, the communication system 200 may include a network equipment 201 and a terminal equipment 202 (for simplicity, Figure 2 only takes one terminal device as an example for illustration).
[0049]
In the embodiment of the present application, the network device 201 and the terminal device 202 can perform existing services or services that can be implemented in the future. For example, these services include but are not limited to: enhanced mobile broadband (eMBB, enhanced Mobile Broadband), massive machine type communication (mMTC, massive machine type communication), and highly reliable and low-latency communication (URLLC, Ultra-Reliable and Low- Latency Communication), etc.
[0050]
Among them, the terminal device 202 can send data to the network device 101, for example, using an authorized or unauthorized transmission mode. The terminal device 201 can receive data sent by one or more terminal devices 202, and feed back information to the terminal device 202, such as acknowledged ACK/non-acknowledged NACK information, etc. The terminal device 202 can confirm the end of the transmission process according to the feedback information, or can further Perform new data transmission, or data retransmission can be performed.
[0051]
In addition, before the terminal device 202 accesses the network device 201, the network device 201 can send information related to system information to the terminal device 102, and the terminal device 202 detects the received information to achieve downlink synchronization and communicate with the network device 201. establish connection.
[0052]
The following takes the network device in the communication system as the sender or receiver, and the terminal device as the receiver or sender as an example, but the application is not limited to this, and the sender and/or receiver can also be other devices . For example, this application is not only applicable to signal transmission between network equipment and terminal equipment, but also applicable to signal transmission between two terminal equipment.
[0053]
In the following embodiments of this application, the four-step random access process refers to a four-step (4-step) contention based random access (CBRA, Contention Based Random Access) process, which can also be written as a 4-step random access process. Entry process, or 4-step CBRA.
[0054]
In the following embodiments of this application, the two-step random access process refers to a two-step (2-step) contention based random access (CBRA, Contention Based Random Access) process, which can also be written as a 2-step random access process. Entry process, or 2-step CBRA.
[0055]
Example 1
[0056]
Embodiment 1 of the present application provides a random access method, which can be executed by a terminal device.
[0057]
FIG. 3 is a schematic diagram of the random access method of this embodiment. As shown in FIG. 3, the method includes:
[0058]
Step 301: The terminal device initiates a two-step random access process; and
[0059]
Step 302: When the two-step random access process is not completed, the terminal device initiates a non-competitive random access process or a four-step random access process.
[0060]
According to this embodiment, when the two-step random access process is not completed, the terminal device initiates a non-competitive random access process or a four-step random access process, thus, in the case of two-step random access failure, it can improve The efficiency of random access avoids the increase of transmission delay.
[0061]
In this embodiment, the two-step random access process is not completed, which refers to at least one of the following situations:
[0062]
Case 1. The terminal device does not receive a random access response within the random access response receiving window after sending the first message of the two-step random access process, where the first message may be MsgA.
[0063]
For example, the terminal device does not receive the random access response MsgB for 2-step random access contention resolution within the random access response receiving window, and does not receive the random access response MsgB for indicating the content within the random access response receiving window. The terminal device sends a 4-step random access Msg3 random access response, where MsgB can carry contention resolution information, and instructs the terminal device to send a 4-step random access msg3 random access response that can carry the uplink sending the msg3 Resource authorization.
[0064]
Case 2. The random access contention resolution in the two-step random access process is unsuccessful.
[0065]
For example: the terminal device receives the random access response MsgB sent by the network device, but the contention resolution information contained in the MsgB does not match the information sent in the MsgA. Therefore, it cannot successfully resolve the random access during the two-step random access process. Access competition.
[0066]
Case 3: The number of sending two-step random access preamble reaches the maximum threshold, where the number of sending two-step random access preamble can be represented by the following parameter: PREAMBLE_TRANSMISSION_COUNTER.
[0067]
Case 4. The power of transmitting the two-step random access preamble and/or the power of the physical uplink shared channel (PUSCH) reaches the maximum threshold. The maximum threshold of power can be represented by the parameter Pcmax, for example.
[0068]
For example, the power of the preamble of Msg A for 2-step random access reaches the maximum transmission threshold, or the power of the PUSCH for Msg A for 2-step random access reaches the maximum transmission threshold, or the power of 2-step random access is transmitted. The sum of the power of the MsgA preamble and PUSCH reaches the maximum transmission threshold.
[0069]
In step 302 of this embodiment, when the two-step random access process in step 301 is not completed, the terminal device may initiate a non-competitive random access process or a four-step random access process.
[0070]
In the following, in different implementation manners, the initiation of the non-competitive random access process and the four-step random access process in step 302 are respectively described.
[0071]
Implementation mode one,
[0072]
In the first embodiment, when the two-step random access process is not completed, the terminal device initiates a non-competitive random access process.
[0073]
Fig. 4 is a schematic diagram of a method for a terminal device to initiate a non-competitive random access process. As shown in Fig. 4, the method includes:
[0074]
Step 401: When the configuration information of non-competitive random access is stored, the terminal device decides to initiate a non-competitive random access process; or, when the configuration information of non-competitive random access is stored, according to the network device The first instruction to initiate a non-contention random access procedure.
[0075]
In this embodiment, the terminal device may receive the configuration information of non-competitive random access sent by the network device, and save the configuration information of non-competitive random access.
[0076]
In this embodiment, the configuration information of non-competitive random access saved by the terminal device may at least include: candidate synchronization signal of non-competitive random access/physical broadcast channel block (SS/PBCH Block, SSB) configuration information, and The configuration information of the preamble corresponding to the candidate synchronization signal/physical broadcast channel block; or, the configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the configuration information of the channel state information reference signal (CSI-RS). -RS) the configuration information of the corresponding preamble and the configuration information of the sending opportunity of the preamble.
[0077]
In this embodiment, the terminal device can use radio resource control (RRC) messages, and/or physical downlink control channel (PDCCH) instructions at the physical layer, and/or random access response messages at the media access control (MAC) layer To receive configuration information for non-contention random access.
[0078]
In this embodiment, the RRC message carrying the configuration information of the non-contention random access may be a dedicated RRC message for the terminal device. The non-competitive random access configuration information in the RRC message may include: candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) for non-competitive random access, and configuration information of the preamble corresponding to the candidate SSB Or, the configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the configuration information of the preamble corresponding to the channel state information reference signal (CSI-RS) and the transmission opportunity of the preamble Configuration information.
[0079]
In addition, the non-contention random access configuration information in the RRC message may also include at least one of the following information: the total number of available contention and non-contention random access preambles, and the physical random access channel (PRACH) root sequence index , The preamble subcarrier interval, the terminal equipment selects the preset non-competitive random access candidate SSB required synchronization reference signal (SS-RS) measurement reference signal received power (RSRP) threshold, the terminal equipment selects the preset non-competitive random access The measured RSRP threshold of the CSI-RS required to access the candidate CSI-RS, the set of transmission opportunities for non-competitive random access preamle, the number of preamble transmission opportunities distributed in the frequency domain, and the preamble transmission opportunity at the beginning of the frequency domain. The preamble power climb step length factor, the maximum number of transmissions of the preamble for non-contention random access, the length of the random access response receiving window, and the target receiving power of the preamble.
[0080]
In this embodiment, the non-contention random access configuration information in the PDCCH command or the MAC layer random access response message may include: candidate synchronization signal for non-contention random access/physical broadcast channel block (SS/PBCH Block, SSB) , And the configuration information of the preamble corresponding to the candidate SSB; or, the configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the channel state information reference signal (CSI-RS) The configuration information of the corresponding preamble and the configuration information of the sending opportunity of the preamble.
[0081]
In step 401, when the terminal device stores the configuration information of non-competitive random access, when the above two-step random access process is not completed (for example, when at least one of the above cases 1 to 4 occurs) ), you can decide on your own to initiate a non-competitive random access process, that is, the configuration information of non-competitive random access saved by a terminal device is equivalent to implicitly indicating to the terminal device to initiate a non-competitive random access process.
[0082]
For example, if the terminal device has received an RRC message containing non-competitive random access configuration information sent by a network device, or/and, when the 2-step random access process is not completed, the terminal device has received a non-competitive random access configuration For the MAC layer control information or physical layer PDCCH command of the information, the terminal device can decide to initiate a non-competitive random access process by itself. The terminal device receives the MAC layer control information containing the non-competitive random access configuration information when the 2-step random access process is not completed. For example, it may be: after the terminal device sends the MsgA of 2-step RACH, the A random access response containing non-contention random access configuration information is received in the access response receiving window.
[0083]
In step 401, the terminal device may initiate a non-competition random access process according to the first instruction of the network device when the configuration information of the non-competition random access is stored.
[0084]
The terminal device may receive the first instruction through an RRC message, and/or a physical downlink control channel (PDCCH) instruction of the physical layer, and/or a random access response message of the medium access control (MAC) layer. Among them, the RRC message is a system broadcast message or a dedicated RRC message for the terminal device. The random access response message of the MAC layer may be a specific type of random access response message, that is, the network device sends the specific type of random access response message as the first indication to the terminal device. The specific type of random access response message may be, for example, a random access response message that does not carry contention resolution information and/or does not carry an uplink transmission authorization.
[0085]
In a specific example, the network device may send a random access response message that does not carry contention resolution information and/or does not carry the uplink transmission authorization to the terminal device to instruct the terminal device to initiate a non-competition random access process. The random access response is received in the access response receiving window, and a non-competitive random access process is initiated.
[0086]
As shown in Figure 4, the method for a terminal device to initiate a non-competitive random access process may further include:
[0087]
Step 402: Perform initialization of the non-contention random access process when the two-step random access is not completed.
[0088]
In step 402, the initialization may include: configuring non-contention random access parameters. For example, from RRC messages, and/or PDCCH instructions, and/or MAC layer random access response messages to obtain non-contention random access parameters, these parameters can be used for non-contention random access preamble selection, and preamble transmission resources And transmit power configuration.
[0089]
In step 402 of this embodiment, the configured non-contention random access parameters include public parameters and proprietary parameters.
[0090]
In this embodiment, the common parameter may include at least one of the following parameters:
[0091]
The set of sending opportunities for non-competitive random access preamle, for example, this parameter can be expressed as prach-ConfigurationIndex;
[0092]
The target received power of the preamble for non-competitive random access, for example, this parameter can be expressed as preambleReceivedTargetPower;
[0093]
The terminal device selects the SS-RS measurement RSRP threshold required by the designated non-competitive random access candidate SSB. For example, this parameter can be expressed as rsrp-ThresholdSSB;
[0094]
The terminal device selects the measurement RSRP threshold required by the uplink carrier in the conventional uplink (NUL, Normal Uplink) and supplementary uplink (SUL, Supplementary Uplink) carriers, for example, this parameter can be expressed as rsrp-ThresholdSSB-SUL;
[0095]
The power ramping step factor of the non-competitive random access preamble, for example, this parameter can be expressed as powerRampingStep;
[0096]
The maximum number of transmissions of the preamble for non-competitive random access, for example, this parameter can be expressed as preambleTransMax;
[0097]
The length of the non-contention random access response reception window, for example, this parameter can be expressed as ra-ResponseWindow.
[0098]
In this embodiment, the dedicated parameter may include at least one of the following parameters:
[0099]
The terminal device selects the CSI-RS measurement RSRP threshold required for the designated non-competitive random access candidate CSI-RS, for example, this parameter can be expressed as rsrp-ThresholdCSI-RS;
[0100]
The set of preamble sending opportunities related to the designated non-competitive random access candidate SSB. For example, this parameter can be expressed as ra-ssb-OccasionMaskIndex;
[0101]
A set of preamble transmission opportunities related to the designated non-competitive random access candidate CSI-RS. For example, this parameter may be expressed as ra-OccasionList.
[0102]
In step 402 of this embodiment, the above-mentioned common parameters can be obtained from the saved configuration information of non-competitive random access described in step 401, or can be obtained from parameters reused with the original non-competitive random access parameters. Obtained, for example: some of the public parameters are obtained from the configuration information of non-competitive random access, and the other part of the public parameters are obtained from the parameters reused with the original non-competitive random access parameters; or, all public parameters are obtained from the non-competitive random access parameters. It is obtained from the configuration information of random access; or, all public parameters are obtained from the parameters reused with the original non-competitive random access parameters.
[0103]
In step 402 of this embodiment, the above-mentioned proprietary parameters can be obtained from the stored configuration information of non-contention random access described in step 401.
[0104]
As shown in Figure 4, the method for a terminal device to initiate a non-competitive random access process may further include:
[0105]
Step 403: Determine the preamble of the non-contention random access to be sent when the two-step random access is not completed.
[0106]
In this embodiment, the preamble of the non-contention random access can be determined according to the synchronization signal/physical broadcast channel block (SSB), or the non-contention random access can be determined according to the channel state information reference signal (CSI-RS) The preamble.
[0107]
Fig. 5 is a schematic diagram of a method for determining a preamble for non-competitive random access according to SSB. As shown in Fig. 5, the method includes:
[0108]
Step 501: Select the used synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) from candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB); and
[0109]
Step 502: Determine the preamble corresponding to the selected synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) as the non-contention random access preamble to be sent.
[0110]
In this embodiment, the configuration information of the candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) and the preamble corresponding to the candidate SSB may be included in the non-contention random access configuration information described in step 401. The configuration information of the non-contention random access may come from the RRC message, and/or the PDCCH command, and/or the MAC layer random access response message.
[0111]
In step 501, the terminal device may measure the candidate synchronization signal/synchronization reference signal (SS-RS) received power of the physical broadcast channel block (SS/PBCH Block, SSB) in the configuration information of the non-competitive random access, and according to this The measured synchronization reference signal (SS-RS) received power, and the SSB to be used is selected from the candidate SSB. For example, the terminal device selects an SSB with a synchronization reference signal (SS-RS) received power higher than a first pre-configured threshold (for example, denoted as rsrp-ThresholdSSB) from the candidate SSBs as the used SSB.
[0112]
In step 502, according to the used SSB selected in step 501 and the configuration information of the preamble corresponding to the candidate SSB, the preamble corresponding to the selected used SSB is determined.
[0113]
Fig. 6 is a schematic diagram of a method for determining a preamble for non-contention random access based on CSI-RS. As shown in Fig. 6, the method includes:
[0114]
Step 601: Select a channel state information reference signal to be used from candidate channel state information reference signals (CSI-RS); and
[0115]
Step 602: Determine the preamble corresponding to the selected channel state information reference signal (CSI-RS) as the non-contention random access preamble to be sent.
[0116]
In this embodiment, the candidate channel state information reference signal (CSI-RS) and the configuration information of the preamble corresponding to the candidate channel state information reference signal (CSI-RS) may be included in the non-competitive random access described in step 401. Configuration information. The configuration information of the non-contention random access may come from the RRC message, and/or the PDCCH command, and/or the MAC layer random access response message.
[0117]
In step 601, the terminal device may measure the received power of the candidate channel state information reference signal (CSI-RS) in the configuration information of the non-competitive random access, and based on the measured channel state information reference signal (CSI-RS) The received power of CSI-RS is selected from the candidate CSI-RS. For example, the terminal device selects a CSI-RS with a CSI-RS received power higher than a second pre-configured threshold (for example, represented as rsrp-ThresholdCSI-RS) from the candidate CSI-RS as the used CSI-RS.
[0118]
In step 602, the preamble corresponding to the selected CSI-RS used is determined according to the CSI-RS used selected in step 601 and the configuration information of the preamble corresponding to the candidate CSI-RS.
[0119]
As shown in Figure 4, the method for a terminal device to initiate a non-competitive random access process may further include:
[0120]
Step 404: Select an uplink transmission resource for transmitting the preamble of the non-contention random access when the two-step random access is not completed.
[0121]
In step 404 of this embodiment, the terminal device may select the synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) from the non-competitive random access candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) in step 501. SS/PBCH Block, SSB) or the channel state information reference signal (CSI-RS) selected from the non-competitive random access candidate channel state information reference signal (CSI-RS) in step 601, and select to send the non-competitive random access The physical random access channel opportunity (PRACH occasion) of the preamble.
[0122]
For example, if the SSB is selected (e.g., step 501), the terminal device can transmit the opportunity configuration parameter (e.g., parameter ra- Select the next available physical random access channel (PRACH) transmission opportunity from the set of allowed preamble transmission opportunities identified by ssb-OccasionMaskIndex).
[0123]
For another example, if the CSI-RS is selected (e.g., step 601), the terminal device may configure the physical random access channel (PRACH) corresponding to the CSI-RS in the configuration information of non-competitive random access ( For example, among the allowed preamble transmission opportunities identified by the parameter ra-OccasionList), the next available physical random access channel (PRACH) transmission opportunity is selected.
[0124]
Fig. 7 is a schematic diagram of the next available physical random access channel (PRACH) transmission opportunity in this embodiment. As shown in Figure 7, the current time is t0, the next PRACH transmission opportunity allowed is P1, the next PRACH transmission opportunity allowed is P2, the time corresponding to PRACH transmission opportunity P1 is t1, and the time corresponding to PRACH transmission opportunity P2 Is t2. The length of time between time t0 and time t1 is T1, and the length of time between time t0 and time t2 is T2.
[0125]
Assuming that the length of time the terminal device prepares to send the preamble for non-contention random access is T0, if T0≤T1, then PRACH transmission opportunity P1 is the next available PRACH transmission opportunity; if T0>T1, then PRACH transmission The opportunity P1 is an unavailable PRACH transmission opportunity, and if T0≤T2, then the PRACH transmission opportunity P2 is the next available PRACH transmission opportunity.
[0126]
As shown in Figure 4, the method for a terminal device to initiate a non-competitive random access process may further include:
[0127]
Step 405: Calculate the target received power of the random access preamble; and
[0128]
Step 406: Calculate the transmit power of the random access preamble according to the target received power and path loss of the random access preamble.
[0129]
In step 405 of this embodiment, multiple methods can be used to calculate the target received power of the random access preamble.
[0130]
In one method, it can be based on the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble, and the power ramp of the random access preamble. The step factor PREAMBLE_POWER_RAMPING_STEP is used to calculate the target received power of the random access preamble.
[0131]
In this method, for example, the target received power of the random access preamble can be calculated by the following formula (1):
[0132]
Random access preamble target received power =
[0133]
preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×PREAMBLE_POWER_RAMPING_STEP(1)
[0134]
Among them, the power ramp-up step factor PREAMBLE_POWER_RAMPING_STEP of the random access preamble and the target received power parameter of the random access preamble preambleReceivedTargetPower are parameters obtained from the configuration information of non-competitive random access, and the first target received power offset value DELTA_PREAMBLE It is a pre-set parameter related to the preamble format and the subcarrier spacing for transmitting the preamble.
[0135]
In another method, the power of the random access preamble can be based on the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, and the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble. The climb step factor PREAMBLE_POWER_RAMPING_STEP and the second target received power offset value delta_fallback_TargetPower are used to calculate the target received power of the random access preamble.
[0136]
In this method, for example, the target received power of the random access preamble can be calculated by the following formula (2):
[0137]
Random access target received power=preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×PREAMBLE_POWER_RAMPING_STEP+delta_fallback_TargetPower(2)
[0138]
In this method, the second target received power offset value delta_fallback_TargetPower is a value greater than zero. Therefore, the target received power is higher than that of ordinary random access, so that the priority of the non-competitive random access process can be higher than that of ordinary random access. The priority of the entry process is high.
[0139]
In this method, the second target received power offset value delta_fallback_TargetPower is a preset fixed value, or it is related to the climb range of the target received power of the preamble of the uncompleted two-step random access.
[0140]
For example, the second target received power offset value delta_fallback_TargetPower is linearly related to the ramp rate of the target received power of the preamble of the uncompleted two-step random access.
[0141]
In a specific example, delta_fallback_TargetPower can be calculated by the following formula (3):
[0142]
delta_fallback_TargetPower=β×(PREAMBLE_POWER_RAMPING_COUNTER'–1)×PREAMBLE_POWER_RAMPING_STEP'(3)
[0143]
Among them, β is the linear correlation factor, PREAMBLE_POWER_RAMPING_COUNTER' is the power climbing count of unfinished 2-step random access, and PREAMBLE_POWER_RAMPING_STEP' is the target received power climbing step length of 2-step random access.
[0144]
In another method, the power of the random access preamble can be determined according to the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, and the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble. The climb step factor PREAMBLE_POWER_RAMPING_STEP and the target received power climb step offset value delta_fallback_step are used to calculate the target received power of the random access preamble.
[0145]
In this method, for example, the target received power of the random access preamble can be calculated by the following formula (4):
[0146]
Random access preamble target received power=preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×(PREAMBLE_POWER_RAMPING_STEP+delta_fallback_step)(4)
[0147]
In this method, the target received power climb step offset value delta_fallback_step is a value greater than zero. Therefore, the target received power climbs faster than ordinary random access, so that the priority of the non-competitive random access process can be higher. The priority of the ordinary random access procedure is high.
[0148]
In the above equations (1), (2), and (4), the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble is used to record the number of preamble transmit power ramps. Each time the non-competitive random access preamble is sent When the code is increased by 1, therefore, each time the preamble is sent when the terminal device has not completed random access, the target received power of the preamble is increased by one step.
[0149]
In this embodiment, the initial value of the power ramp-up counter value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble can be equal to:
[0150]
The preset initial value, that is, when the terminal device initiates a non-competitive random access process, the initial value of the power ramp-up counter value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble is the preset initial value. The preset initial value is, for example, 1; or, the preamble power ramp count value of the unfinished two-step random access, that is, the initial value of the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble when the terminal device initiates a non-competitive random access process It is equal to the current value of the preamble power climb count of the unfinished two-step random access.
[0151]
In step 406 of this embodiment, the specific method for calculating the transmit power of the random access preamble can refer to the prior art, which will not be described in this embodiment.
[0152]
As shown in Figure 4, the method for a terminal device to initiate a non-competitive random access process may further include:
[0153]
Step 407: According to the selected random access preamble, the uplink transmission resources of the selected random access preamble, and the calculated transmission power of the random access preamble, send non-competitive data when the two-step random access is not completed. Random access preamble.
[0154]
According to the above steps 401 to 407, when the two-step random access process is not completed, the terminal device initiates a non-competitive random access process.
[0155]
Implementation mode two
[0156]
In the second embodiment, when the two-step random access process is not completed, the terminal device initiates a four-step random access process.
[0157]
Fig. 8 is a schematic diagram of a method for a terminal device to initiate a four-step random access procedure. As shown in Fig. 8, the method includes:
[0158]
Step 801: The terminal device decides to initiate a four-step random access process; or, according to the second instruction of the network device, initiates a four-step random access process.
[0159]
In step 801, when the two-step random access process is not completed (for example, when at least one of the above cases 1 to 4 occurs), the terminal device may decide to initiate a four-step random access process by itself.
[0160]
In step 801, the terminal device may also initiate a four-step random access process according to the second instruction of the network device.
[0161]
The terminal device may receive the second indication through a radio resource control (RRC) message and/or a random access response message of the medium access control (MAC) layer. The random access response message of the MAC layer may be a specific type of random access response message, that is, the network device sends the specific type of random access response message to the terminal device as a second indication. The specific type of random access response message may be, for example, a random access response message that does not carry contention resolution information and/or does not carry an uplink transmission authorization. Among them, the RRC message may be a system broadcast message or dedicated RRC signaling.
[0162]
For example, the second indication information may be load indication information of the random access channel sent by the network device, and the terminal device may decide to initiate a four-step random access process according to the load indication information of the random access channel. That is to say, the network device can detect the preamble transmission opportunity of the two-step random access and/or the collision rate or load condition in the PUSCH transmission opportunity, or it can further detect the preamble transmission opportunity of the 4-step random access For collision rate or load conditions, the load indication information of the random access channel is sent to the terminal device as the second indication information.
[0163]
In the case where the foregoing second indication information is load indication information of the random access channel, the load indication information may be a load factor of 0 to 1.
[0164]
In one method, the smaller the load factor, the more idle the two-step random access channel is. After receiving the second indication information, the terminal generates a random number between 0 and 1 with a uniformly distributed probability. If the random number is greater than With this load factor, the terminal device initiates a four-step random access process, otherwise, the terminal device continues to initiate a two-step random access process.
[0165]
In another method, the smaller the load factor indicates that the collision rate and load of the two-step random access channel are higher. After receiving the second indication information, the terminal generates a random number between 0 and 1 with a uniformly distributed probability. If the random number is less than the load factor, the terminal device initiates a four-step random access process; otherwise, the terminal device continues to initiate a two-step random access process.
[0166]
In a specific example, if the terminal device has received an RRC message sent by the network device that instructs the terminal device to initiate a 4-step random access process (for example, the RRC message may include the above-mentioned load indication information of the random access channel) ), or/and, when the terminal device receives the MAC layer control information that instructs the terminal device to initiate the 4-step random access process when the 2-step random access process is not completed, the terminal device can decide to initiate a competing 4-step random access process.入程。 Into the process. Wherein, the terminal device receives the MAC layer control information instructing the terminal device to initiate the 4-step random access procedure when the 2-step random access procedure is not completed. A random access response message that does not carry contention resolution information and/or does not carry an uplink transmission authorization is received in the random access response receiving window. Wherein, the RRC message received by the terminal equipment indicating the 4-step random access process in which the terminal equipment initiates competition may be system broadcast information or dedicated RRC signaling.
[0167]
As shown in Figure 8, the method for the terminal device to initiate a four-step random access procedure may also include:
[0168]
Step 802: Perform the initialization of the four-step random access process when the two-step random access is not completed.
[0169]
In step 802, the initialization may include: configuring four-step random access parameters. For example, the four-step random access parameters are obtained from the four-step random access configuration information, and these parameters can be used for the selection of the four-step random access preamble and the configuration of preamble transmission resources and transmission power.
[0170]
In step 802, the configured four-step random access parameters may include at least one of the following parameters:
[0171]
The 4-step random access set of sending opportunities for preamle, for example, can be expressed as the parameter prach-ConfigurationIndex;
[0172]
The target received power of the 4-step random access preamble, for example, can be expressed as the parameter preambleReceivedTargetPower;
[0173]
The terminal equipment selects the measured RSRP threshold required by the uplink carrier among the conventional uplink (NUL, Normal Uplink) and supplementary uplink (SUL, Supplementary Uplink) carriers, for example, it can be expressed as the parameter rsrp-ThresholdSSB-SUL;
[0174]
The power climbing step factor of 4-step random access to Preamble, for example, can be expressed as the parameter powerRampingStep;
[0175]
The maximum number of preamble transmissions, for example, can be expressed as the parameter preambleTransMax;
[0176]
The SS-RS measurement RSRP threshold required for 4-step random access to select SSB, for example, can be expressed as the parameter rsrp-ThresholdSSB;
[0177]
The number of SSBs sharing the same PRACH occasion and the number of competing random access preambles used by each SSB in the same PRACH occasion, for example, can be expressed as the parameter ssb-perRACH-OccasionAndCB-PreamblesPerSSB;
[0178]
The number of preambles of Preamble group A used by each SSB, for example, can be expressed as the parameter numberOfRA-PreamblesGroupA;
[0179]
The terminal device selects the msg3PDU size threshold of preamble group A, for example, it can be expressed as the parameter ra-Msg3SizeGroupA (per cell);
[0180]
4-step random access contention random access response receiving window length, for example, can be expressed as the parameter ra-ResponseWindow;
[0181]
The length of the 4-step random access contention resolution information reception window, for example, can be expressed as the parameter ra-ContentionResolutionTimer;
[0182]
The terminal device selects the target received power offset of preamble group B, for example, it can be expressed as a parameter messagePowerOffsetGroupB;
[0183]
The target received power offset of msg3, for example, can be expressed as the parameter msg3-DeltaPreamble.
[0184]
In step 802 of this embodiment, the four-step random access parameters configured above can be obtained from the received configuration information of the four-step random access, and/or from the parameters reused with the original competing random access parameters Made in. Wherein, the terminal device can receive the configuration information of the four-step random access via the system broadcast information; the original competing random access is, for example, the original four-step random access.
[0185]
As shown in Figure 8, the method for the terminal device to initiate a four-step random access procedure may also include:
[0186]
Step 803: Determine the preamble of the four-step random access to be sent when the two-step random access is not completed.
[0187]
In this embodiment, the preamble of the four-step random access can be determined according to the synchronization signal/physical broadcast channel block (SSB).
[0188]
Fig. 9 is a schematic diagram of a method for determining a preamble for four-step random access according to SSB. As shown in Fig. 9, the method includes:
[0189]
Step 901: Select a synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) used for four-step random access; and
[0190]
Step 902: Determine the four-step random access preamble to be sent according to the selected SSB.
[0191]
In step 901, the terminal device can measure the received power of the synchronization signal/synchronization reference signal (SS-RS) of the synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) sent by the network device, and select an SS from the measured SSB. -The SSB whose RSRP is higher than the pre-configured threshold (for example, denoted as rsrp-ThresholdSSB) is used as the SSB for four-step random access. In addition, if there is no SSB whose SS-RSRP is higher than the pre-configured threshold (rsrp-ThresholdSSB) among the measured SSBs, the terminal device can select any SSB.
[0192]
In addition, in step 901, the terminal device may not measure the received power of the SSB, but select the SSB selected by the unfinished 2-step random access process as the SSB used for the four-step random access.
[0193]
Fig. 10 is a schematic diagram of a method for determining the four-step random access preamble to be sent according to the selected SSB in step 902. As shown in Fig. 10, the method includes:
[0194]
Step 1001: Determine the preamble group used in the four-step random access procedure; and
[0195]
Step 1002: Randomly select a preamble from the preamble set of the determined preamble group corresponding to the selected SSB as the four-step random access preamble to be sent, wherein each preamble set in the preamble group is selected The probability of each preamble is the same.
[0196]
In step 1001, the preamble group selected in the uncompleted two-step random access process may be determined as the preamble code group used in the four-step random access process.
[0197]
In step 1001, the preamble group can also be reselected. In this embodiment, multiple methods can be used to reselect the preamble group.
[0198]
In one method, in the case that the unfinished two-step random access process is triggered by the common control logical channel (CCCH), the terminal device can be based on the size of the first message (msg A) in the two-step random access process Or according to the size of the second message (msg 3) in the four-step random access process, determine the preamble code group used in the four-step random access process.
[0199]
For example, when the size of the first message (msg A) or the size of the second message (msg 3) is greater than the msg3PDU size threshold of preamble group A in the four-step random access configuration information (for example, expressed as the parameter ra-Msg3SizeGroupA) When setting the value, make sure to use preamble group B, otherwise make sure to use preamble group A.
[0200]
The size of the first message (msg A) is, for example, the size of the media access control layer protocol data unit (MAC PDU) of MsgA; the size of the second message msg 3 is, for example, the MAC PDU of MsgA is copied to the 4-step RACH. The size of the MAC PDU of msg 3 obtained from this in the msg 3 buffer.
[0201]
In another method, in the case that the unfinished two-step random access process is triggered by the uplink data channel, the terminal equipment according to the media access control layer of the second message (msg3) of the potential four-step random access process The size of the protocol data unit (MAC PDU) determines the preamble group used in the four-step random access process.
[0202]
For example, when the media access control layer protocol data unit (MAC PDU) of the second message (msg3) is greater than the value set by the parameter (ra-Msg3SizeGroupA) of the four-step random access configuration information, it is determined to use Preamble group B, otherwise determine to use preamble group A.
[0203]
Among them, the size of the media access control layer protocol data unit (MAC PDU) of the second message (msg3) is the size of the MAC PDU composed of the size of the uplink data that needs to be sent plus the size of the MAC PDU header and the size of the MAC control unit that needs to be sent size.
[0204]
In another method, when the unfinished two-step random access process is triggered by the uplink data channel, the terminal device can determine the preamble group used in the four-step random access process according to the current path loss.
[0205]
For example, when the current path loss is less than the preset path loss threshold, the preamble group B is determined to be used, otherwise, the preamble group B is determined to be used.
[0206]
Among them, the preset path loss threshold=PCMAX-preambleReceivedTargetPower-msg3-DeltaPreamble-messagePowerOffsetGroupB.
[0207]
preambleReceivedTargetPower represents the target received power of the preamble, msg3-DeltaPreamble represents the target received power offset of msg3, messagePowerOffsetGroupB represents the target received power offset of the preamble group B selected by the terminal device, and PCMAC represents the allowed maximum transmit power of the terminal device.
[0208]
In step 1002, a preamble is randomly selected from the preamble set of preamble group A or group B corresponding to the SSB determined by step 1001 as the four-step random access preamble to be sent, where the selected preamble group The probability of each preamble in the set of preambles is the same. For example, step 1001 determines that the preamble group corresponding to the SSB is group A, and in step 1002, randomly select a preamble from the preamble set of preamble group A with a uniformly distributed probability as the four-step random access preamble to be sent code.
[0209]
As shown in FIG. 8, the method for the terminal device to initiate a four-step random access process may further include:
[0210]
Step 804: Select the uplink transmission resource that sends the preamble of the four-step random access when the two-step random access is not completed.
[0211]
In step 804, the terminal device may select the next available physical random access channel (PRACH) transmission opportunity from the set of allowed preamble transmission opportunities identified by the preamble transmission opportunity configuration parameter in the four-step random access configuration information When the two-step random access is not completed, the physical random access channel (PRACH) sending opportunity of the preamble of the four-step random access is sent.
[0212]
For the description of "the next available physical random access channel (PRACH) transmission opportunity", please refer to FIG. 7 and related descriptions.
[0213]
As shown in Figure 8, the method for the terminal device to initiate a four-step random access procedure may also include:
[0214]
Step 805: Calculate the target received power of the random access preamble; and
[0215]
Step 806: Calculate the transmit power of the random access preamble according to the target received power and path loss of the random access preamble.
[0216]
In step 805 of this embodiment, multiple methods can be used to calculate the target received power of the random access preamble.
[0217]
In one method, it can be based on the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble, and the power ramp of the random access preamble. The step factor PREAMBLE_POWER_RAMPING_STEP is used to calculate the target received power of the random access preamble.
[0218]
In this method, for example, the target received power of the random access preamble can be calculated by the above formula (1).
[0219]
Random access preamble target received power =
[0220]
preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×PREAMBLE_POWER_RAMPING_STEP(1)
[0221]
Among them, the power ramp-up step factor PREAMBLE_POWER_RAMPING_STEP of the random access preamble, the target received power parameter of the random access preamble preambleReceivedTargetPower are parameters obtained from the configuration information of the four-step random access, and the first target received power offset value DELTA_PREAMBLE It is a pre-set parameter related to the preamble format and the subcarrier spacing for transmitting the preamble.
[0222]
In another method, the power of the random access preamble can be based on the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, and the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble. The climb step factor PREAMBLE_POWER_RAMPING_STEP and the second target received power offset value delta_fallback_TargetPower are used to calculate the target received power of the random access preamble.
[0223]
In this method, for example, the target received power of the random access preamble can be calculated by the following formula (6):
[0224]
Random access target received power=preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×PREAMBLE_POWER_RAMPING_STEP+delta_fallback_TargetPower(6)
[0225]
In this method, the second target received power offset value delta_fallback_TargetPower is a value greater than zero. Therefore, the target received power is higher than that of ordinary random access, so that the priority of the four-step random access process is higher than that of ordinary random access. The priority of the process is high.
[0226]
In this method, the second target received power offset value delta_fallback_TargetPower is a preset fixed value, or it is related to the climb range of the target received power of the preamble of the uncompleted two-step random access.
[0227]
For example, the second target received power offset value delta_fallback_TargetPower is linearly related to the ramp rate of the target received power of the preamble of the uncompleted two-step random access.
[0228]
In a specific example, the delta_fallback_TargetPower can be calculated by the above formula (3).
[0229]
In another method, the power of the random access preamble can be determined according to the target received power parameter preambleReceivedTargetPower of the random access preamble, the first target received power offset value DELTA_PREAMBLE, and the power ramp count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble. The climb step factor PREAMBLE_POWER_RAMPING_STEP and the target received power climb step offset value delta_fallback_step are used to calculate the target received power of the random access preamble.
[0230]
In this method, for example, the target received power of the random access preamble can be calculated by the following formula (7):
[0231]
Random access preamble target received power=preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER–1)×(PREAMBLE_POWER_RAMPING_STEP+delta_fallback_step)(7)
[0232]
In this method, the target received power climb step offset value delta_fallback_step is a value greater than zero. Therefore, the target received power climbs faster than ordinary random access, so that the priority of the four-step random access process is more ordinary The priority of the random access process is high.
[0233]
In the above equations (5), (6) and (7), the initial value of the power ramp-up count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble can be equal to:
[0234]
The preset initial value, that is, when the terminal device initiates the four-step random access process, the initial value of the power ramp-up counter value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble is the preset initial value, and the preset initial value is, for example, 1; Or, the preamble power ramp-up count value of the unfinished two-step random access, that is, when the terminal device initiates a four-step random access process, the initial value of the power ramp-up count value PREAMBLE_POWER_RAMPING_COUNTER of the random access preamble is equal to The current value of the preamble power climb count for the completed two-step random access.
[0235]
In step 806 of this embodiment, the specific method for calculating the transmit power of the random access preamble can refer to the prior art, which will not be described in this embodiment.
[0236]
As shown in Figure 8, the method for the terminal device to initiate a four-step random access procedure may also include:
[0237]
Step 807: According to the selected random access preamble, the uplink transmission resources of the selected random access preamble, and the calculated transmission power of the random access preamble, send the four-step random access when the two-step random access is not completed. Access the preamble.
[0238]
According to this embodiment, when the two-step random access process is not completed, the terminal device initiates a non-competitive random access process or a four-step random access process, thereby avoiding the failure of two-step random access Increase in transmission delay.
[0239]
Example 2
[0240]
The second embodiment provides a random access method, which is applied to network equipment.
[0241]
FIG. 11 is a schematic diagram of the random access method of the second embodiment.
[0242]
As shown in Figure 11, the method includes:
[0243]
Step 1101: Send non-competitive random access configuration information for the terminal device to initiate a non-competitive random access procedure when the two-step random access procedure is not completed, and/or to instruct the terminal device The first instruction to initiate a non-contention random access process when the two-step random access process is not completed; or
[0244]
Step 1102: Send to the terminal device four-step random access configuration information for the terminal device to initiate the four-step random access process when the two-step random access process is not completed, and/or to instruct the terminal device to When the two-step random access process is not completed, the second instruction of the four-step random access process is initiated.
[0245]
In step 1101 of this embodiment, the second message may be sent through an RRC message, and/or a physical downlink control channel (PDCCH) command at the physical layer, and/or a random access response message at the medium access control (MAC) layer. One instruction. Wherein, the RRC message may be a system broadcast message or a dedicated RRC message.
[0246]
In step 1102 of this embodiment, the second instruction may be sent through an RRC message and/or a random access response message of the medium access control (MAC) layer. Wherein, the RRC message may be a system broadcast message or a dedicated RRC message.
[0247]
In this embodiment, the random access response message of the MAC layer in step 1101 or step 1102 does not carry contention resolution information and/or does not carry an uplink transmission authorization. In this embodiment, the configuration information of non-competitive random access includes at least: configuration information of a candidate SSB for non-competitive random access, and configuration information of a preamble corresponding to the candidate SSB; or, non-competitive random access The configuration information of the candidate channel state information reference signal (CSI-RS), and the configuration information of the preamble corresponding to the channel state information reference signal (CSI-RS) and the configuration information of the transmission opportunity of the preamble.
[0248]
In step 1101 of this embodiment, the non-contention can be sent through an RRC message, and/or a physical downlink control channel (PDCCH) command at the physical layer, and/or a random access response message at the media access control (MAC) layer. Random access configuration information.
[0249]
In this embodiment, the RRC message used to send the configuration information of non-contention random access in step 1101 may be a dedicated RRC message for the terminal device.
[0250]
In step 1102 of this embodiment, the network device may send configuration information of four-step random access through system broadcast information.
[0251]
For example, the second indication information may be load indication information of the random access channel sent by the network device, and the terminal device may decide to initiate a four-step random access process according to the load indication information of the random access channel. That is to say, the network device can detect the preamble transmission opportunity of the two-step random access and/or the collision rate or load condition in the PUSCH transmission opportunity, or it can further detect the preamble transmission opportunity of the 4-step random access For collision rate or load conditions, the load information of the random access channel is sent to the terminal device as the second indication information.
[0252]
In the case where the foregoing second indication information is load indication information of the random access channel, the load indication information may be a load factor of 0 to 1.
[0253]
In one method, the smaller the load factor, the more idle the two-step random access channel is. After receiving the second indication information, the terminal generates a random number between 0 and 1 with a uniformly distributed probability. If the random number is greater than With this load factor, the terminal device initiates a four-step random access process, otherwise, the terminal device continues to initiate a two-step random access process.
[0254]
In another method, the smaller the load factor indicates that the collision rate and load of the two-step random access channel are higher. After receiving the second indication information, the terminal generates a random number between 0 and 1 with a uniformly distributed probability. If the random number is less than the load factor, the terminal device initiates a four-step random access process; otherwise, the terminal device continues to initiate a two-step random access process.
[0255]
In this embodiment, the two-step random access process is not completed, which refers to at least one of the following situations:
[0256]
The terminal device does not receive a random access response within the random access response receiving window after sending the first message (MsgA) of the two-step random access process;
[0257]
The random access contention resolution in the two-step random access process was unsuccessful;
[0258]
The number of times (PREAMBLE_TRANSMISSION_COUNTER) that the terminal device sends the two-step random access preamble (PREAMBLE_TRANSMISSION_COUNTER) reaches the maximum threshold;
[0259]
The power of the two-step random access preamble and/or the power of the PUSCH sent by the terminal device reaches the maximum threshold (Pcmax).
[0260]
According to this embodiment, the network device sends the non-competitive random access configuration information and/or the first instruction to the terminal device, or sends the four-step random access configuration information and/or the second instruction to the terminal device, whereby the terminal device is in When the two-step random access process is not completed, a non-competitive random access process or a four-step random access process can be initiated, thereby avoiding an increase in transmission delay and improving random access efficiency.
[0261]
Example 3
[0262]
This embodiment 3 provides a random access device, which corresponds to the random access method of embodiment 1. Since the principle of the device to solve the problem is similar to the method of embodiment 1, its specific implementation can refer to the method of embodiment 1, and the same content will not be repeated.
[0263]
FIG. 12 is a schematic diagram of the random access device of the third embodiment.
[0264]
As shown in FIG. 12, the random access apparatus 1200 includes: a first control unit 1201 and a second control unit 1202.
[0265]
Among them, the first control unit 1201 controls the terminal device to initiate a two-step random access process; the second control unit 1202 controls the terminal device to initiate a non-competitive random access process or a four-step random access process when the two-step random access process is not completed. Random access process.
[0266]
In this embodiment, the random access apparatus 1200 is set in a terminal device, and the random access apparatus 1200 can control the terminal device so that the terminal device executes the random access method described in Embodiment 1. For the description of the control actions of the random access apparatus 1200, refer to the description of the actions of the terminal device in Embodiment 1.
[0267]
Example 4
[0268]
This embodiment 4 provides a random access device, which corresponds to the random access method of embodiment 2. Since the principle of the device to solve the problem is similar to the method of embodiment 2, so its specific implementation can refer to the method of embodiment 2, and the same content will not be repeated.
[0269]
FIG. 13 is a schematic diagram of the random access device of the fourth embodiment.
[0270]
As shown in FIG. 13, the random access apparatus 1300 includes: a third control unit 1301 or a fourth control unit 1302.
[0271]
In this embodiment, the third control unit 1301 is configured to control the network device to send to the terminal device a non-competitive random access for the terminal device to initiate a non-competitive random access procedure when the terminal device has not completed the two-step random access procedure. Configuration information, and/or a first instruction used to instruct the terminal device to initiate a non-competitive random access process when the two-step random access process is not completed; the fourth control unit 1302 is used to control the network device to send to the terminal device Four-step random access configuration information used for the terminal device to initiate the four-step random access process when the two-step random access process is not completed, and/or used to instruct the terminal device to complete the two-step random access During the process, the second instruction of the four-step random access process is initiated.
[0272]
In this embodiment, the random access device 1300 is set in a network device, and the random access device 1300 can control the network device so that the network device executes the random access method described in Embodiment 2. For the description of the control action of the random access apparatus 1300, refer to the description of the action of the network device in the second embodiment.
[0273]
Example 5
[0274]
The fifth embodiment provides a terminal device. Since the principle of the device to solve the problem is similar to that of the device of the third embodiment, the specific implementation can refer to the implementation of the third embodiment, and the same content will not be repeated.
[0275]
FIG. 14 is a schematic diagram of the structure of a terminal device according to an embodiment of the present application. As shown in FIG. 14, the terminal device 1400 may include: a central processing unit (CPU) 1401 and a memory 1402; the memory 1402 is coupled to the central processing unit 1401. The memory 1402 can store various data; in addition, it also stores a data processing program, and the program is executed under the control of the central processing unit 1401 to instruct the terminal device according to the received signaling.
[0276]
In an embodiment, the functions of the apparatus 1200 of Embodiment 3 may be integrated into the central processing unit 1401 of the terminal device 1400. Wherein, the central processing unit 1401 may be configured to implement the method described in Embodiment 1.
[0277]
For example, the central processing unit 1401 may be configured to perform control so that the terminal device 1400 executes the method of the twelfth embodiment.
[0278]
In addition, for other configurations of the central processing unit 1401, please refer to Embodiment 1, which will not be repeated here.
[0279]
In another embodiment, the above-mentioned device 1200 can be configured separately from the central processing unit 1401. For example, the device 1200 can be configured as a chip connected to the central processing unit 1401, such as the unit shown in FIG. Control to realize the functions of the device 400.
[0280]
In addition, as shown in FIG. 14, the terminal device 1400 may also have a communication module 1403, an input unit 1404, a display 1406, an audio processor 1405, an antenna 1407, a power supply 14014, and the like.
[0281]
According to this embodiment, when the two-step random access process is not completed, the terminal device can initiate a non-competitive random access process or a four-step random access process, thereby avoiding an increase in transmission delay and improving random access efficiency.
[0282]
Example 6
[0283]
The sixth embodiment provides a network device. Since the principle of the device to solve the problem is similar to the method of the second embodiment, the specific implementation can refer to the method of the second embodiment, and the same content will not be repeated.
[0284]
FIG. 15 is a schematic diagram of the structure of a network device according to an embodiment of the present invention. As shown in FIG. 15, the network device 1500 may include: a central processing unit (CPU) 1501 and a memory 1502; the memory 1502 is coupled to the central processing unit 1501. The memory 1502 can store various data; in addition, it also stores data processing programs, which are executed under the control of the central processing unit 1501.
[0285]
In an embodiment, the functions of the apparatus 1300 of Embodiment 4 may be integrated into the central processing unit 1501. Wherein, the central processing unit 1501 may be configured to implement the method described in the second embodiment.
[0286]
For example, the central processing unit 1501 may be configured to perform control so that the network device 1500 executes the method of the second embodiment.
[0287]
In addition, for other configurations of the central processing unit 1501, please refer to Embodiment 2, which will not be repeated here.
[0288]
In another embodiment, the device 1300 can be configured separately from the central processing unit 1501. For example, the device 1300 can be configured as a chip connected to the central processing unit 1501, such as the unit shown in FIG. 15, which is controlled by the central processing unit 1501. To realize the function of the device 1300.
[0289]
In addition, as shown in FIG. 15, the network device 1500 may also include a transceiver 1503, an antenna 1504, a display, an audio processor, and a power supply. Among them, the functions of the above-mentioned components are similar to those of the prior art, and will not be repeated here. It is worth noting that the network device 1500 does not necessarily include all the components shown in FIG. 15; in addition, the network device 1500 may also include components not shown in FIG. 15, which can refer to the prior art.
[0290]
Example 7
[0291]
The seventh embodiment provides a communication system, which includes at least the network device 1500 in the sixth embodiment and the terminal device 1400 in the fifth embodiment. The contents of Embodiment 5 and Embodiment 6 are combined here, and will not be repeated here.
[0292]
An embodiment of the present invention also provides a storage medium storing a computer readable program, wherein the computer readable program enables a random access device or terminal device to execute the random access method described in Embodiment 1.
[0293]
The embodiment of the present invention also provides a computer readable program, wherein when the program is executed in a random access device or terminal device, the program causes the random access device or terminal device to execute the method described in Embodiment 1. Random access method.
[0294]
The embodiment of the present invention also provides a storage medium storing a computer readable program, wherein the computer readable program causes a random access apparatus or network device to execute the random access method described in Embodiment 2.
[0295]
The embodiment of the present invention also provides a computer-readable program, wherein when the program is executed in a random access device or network device, the program causes the random access device or network device to execute the random access device or network device described in Embodiment 2. Access method.
[0296]
The above devices and methods of the present invention can be implemented by hardware, or can be implemented by hardware combined with software. The present invention relates to such a computer-readable program, when the program is executed by a logic component, the logic component can realize the above-mentioned device or constituent component, or the logic component can realize the above-mentioned various methods Or steps. The present invention also relates to storage media for storing the above programs, such as hard disks, magnetic disks, optical disks, DVDs, flash memory, and the like.
[0297]
The processing methods in each device described in conjunction with the embodiments of the present invention may be directly embodied in hardware, a software module executed by a processor, or a combination of the two. For example, one or more of the functional block diagrams shown in FIGS. 12 and 13 and/or one or more combinations of the functional block diagrams may correspond to each software module of the computer program flow or each hardware module. These software modules can respectively correspond to the steps shown in FIG. 2. These hardware modules can be implemented, for example, by using a field programmable gate array (FPGA) to solidify these software modules.
[0298]
The software module can be located in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM or any other form of storage medium known in the art. A storage medium may be coupled to the processor, so that the processor can read information from the storage medium and write information to the storage medium; or the storage medium may be a component of the processor. The processor and the storage medium may be located in the ASIC. The software module can be stored in the memory of the mobile terminal, or can be stored in a memory card that can be inserted into the mobile terminal. For example, if the device (such as a mobile terminal) uses a larger-capacity MEGA-SIM card or a large-capacity flash memory device, the software module can be stored in the MEGA-SIM card or a large-capacity flash memory device.
[0299]
One or more of the functional block diagrams described in FIGS. 12 and 13 and/or one or more combinations of the functional block diagrams can be implemented as a general-purpose processor or a digital signal processor (DSP) for performing the functions described in this application. , Application Specific Integrated Circuit (ASIC), Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, or any suitable combination thereof. One or more of the functional block diagrams described in FIGS. 12 and 13 and/or one or more combinations of the functional block diagrams can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, and multiple micro-processing Or any other such configuration.
[0300]
The present invention has been described above in conjunction with specific embodiments, but it should be clear to those skilled in the art that these descriptions are all exemplary and do not limit the protection scope of the present invention. Those skilled in the art can make various variations and modifications to the present invention based on the principles of the present invention, and these variations and modifications are also within the scope of the present invention.
[0301]
This application also provides the following supplementary notes:
[0302]
1. A random access method applied to terminal equipment, the method comprising:
[0303]
The terminal device initiates a two-step random access procedure; and
[0304]
When the two-step random access process is not completed, the terminal device initiates a non-competitive random access process or a four-step random access process.
[0305]
2. The method according to appendix 1, wherein the incomplete two-step random access procedure refers to at least one of the following situations:
[0306]
After sending the first message (MsgA) of the two-step random access procedure, no random access response is received within the random access response receiving window;
[0307]
The random access contention resolution in the two-step random access process is unsuccessful;
[0308]
The number of times of sending the two-step random access preamble reaches the maximum threshold;
[0309]
The power of the two-step random access preamble and/or the power of the physical uplink shared channel (PUSCH) reaches the maximum threshold.
[0310]
3. The method according to any one of appendix 1 to 2, wherein the initiating a non-competitive random access process or a four-step random access process includes:
[0311]
Deciding to initiate a non-competitive random access process when the configuration information of non-competitive random access is saved, or the terminal device decides to initiate a four-step random access process; or
[0312]
In the case where the configuration information of the non-competitive random access is stored, the non-competitive random access procedure is initiated according to the first instruction of the network device, or the terminal device initiates the four-step random access procedure according to the second instruction of the network device .
[0313]
4. The method as described in Appendix 3, wherein:
[0314]
The configuration information of non-competitive random access includes at least:
[0315]
The configuration information of the candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) for non-competitive random access, and the configuration information of the preamble corresponding to the candidate synchronization signal/physical broadcast channel block; or
[0316]
The configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the configuration information of the preamble corresponding to the channel state information reference signal (CSI-RS) and the transmission opportunity of the preamble Configuration information.
[0317]
5. The method as described in appendix 3 or 4, wherein:
[0318]
The non-contention random access is received through a radio resource control (RRC) message, and/or a physical downlink control channel (PDCCH) command at the physical layer, and/or a random access response message at the medium access control (MAC) layer Configuration information.
[0319]
6. The method according to any one of Supplementary Notes 3 to 5, wherein:
[0320]
The first instruction is received through an RRC message, and/or a physical downlink control channel (PDCCH) instruction of the physical layer, and/or a random access response message of the medium access control (MAC) layer.
[0321]
7. The method according to any one of supplementary notes 3 to 5, wherein:
[0322]
The second indication is received through a radio resource control (RRC) message and/or a random access response message of the medium access control (MAC) layer.
[0323]
8. The method according to Supplement 6 or 7, wherein:
[0324]
The random access response message of the MAC layer does not carry contention resolution information and/or does not carry an uplink transmission authorization.
[0325]
9. The method according to any one of Supplementary Notes 1 to 7, wherein:
[0326]
The initiating non-competitive random access process includes:
[0327]
Initialize the non-contention random access process when the two-step random access is not completed;
[0328]
The initiating four-step random access process includes:
[0329]
When the two-step random access is not completed, the initialization of the four-step random access process is performed.
[0330]
10. The method as described in Supplement 9, wherein:
[0331]
When the non-contention random access procedure is initialized when the two-step random access is not completed,
[0332]
The configured non-competitive random access parameters include public parameters and proprietary parameters,
[0333]
in,
[0334]
The public parameters are obtained from the configuration information of the non-competitive random access, and/or obtained from the parameters reused with the original non-competitive random access parameters,
[0335]
The specific parameters are obtained from the configuration information of the non-competitive random access.
[0336]
11. The method as described in Appendix 9, wherein:
[0337]
When the initialization of the four-step random access process is performed when the two-step random access is not completed,
[0338]
The configured four-step random access parameters are obtained from the received configuration information of the four-step random access, and/or obtained from the parameters reused with the original competing random access parameters.
[0339]
12. The method according to any one of Supplementary Notes 9 to 11, wherein:
[0340]
The initiation of the non-competitive random access process further includes: determining the preamble of the non-competitive random access to be sent when the two-step random access is not completed;
[0341]
The initiation of the four-step random access procedure further includes:
[0342]
Determine the preamble of the four-step random access to be sent when the two-step random access is not completed.
[0343]
13. The method according to appendix 12, wherein the determining the non-contention random access preamble to be sent when the two-step random access is not completed includes:
[0344]
Measure the received power of the synchronization reference signal (SS-RS) of the candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) in the configuration information of the non-competitive random access, and obtain from the candidate synchronization signal/physical broadcast The synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) selected for use in the channel block (SS/PBCH Block, SSB); and
[0345]
The preamble corresponding to the selected synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) is determined as the non-contention random access preamble to be sent.
[0346]
14. The method according to appendix 12, wherein the determining the non-contention random access preamble to be sent when the two-step random access is not completed includes:
[0347]
Measure the received power of the candidate channel state information reference signal (CSI-RS) in the non-competitive random access configuration information, and select the channel state information reference signal for use from the candidate channel state information reference signal (CSI-RS) ;as well as
[0348]
The preamble corresponding to the selected channel state information reference signal is determined as the non-contention random access preamble to be sent.
[0349]
15. The method according to appendix 12, wherein the determining the four-step random access preamble to be sent when the two-step random access is not completed includes:
[0350]
Measure the received power of the synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) synchronization reference signal (SS-RS) sent by the network equipment, and select the synchronization signal/physical broadcast channel block ( SS/PBCH Block, SSB); and
[0351]
Determine the four-step random access preamble to be sent according to the selected SSB.
[0352]
16. The method according to appendix 15, wherein the selecting the four-step random access preamble to be sent according to the selected SSB includes:
[0353]
Determine the preamble group used in the four-step random access procedure; and
[0354]
Randomly select a preamble from the preamble set of the determined preamble group corresponding to the selected SSB as the four-step random access preamble to be transmitted, wherein the preamble set of the preamble group is selected The probability of each preamble is the same.
[0355]
17. The method according to appendix 16, wherein the determining the preamble group used in the four-step random access includes:
[0356]
It is determined that the preamble code group used in the four-step random access process is the preamble code group selected in the uncompleted two-step random access process.
[0357]
18. The method according to appendix 16, wherein the determining the preamble group used in the four-step random access procedure includes:
[0358]
In the case where the two-step random access procedure is triggered by a common control logical channel (CCCH),
[0359]
According to the size of the first message (msg A) in the two-step random access process or the size of the second message (msg3) in the four-step random access process, determine the four-step random access process to use The preamble group (A or B).
[0360]
19. The method as described in Supplement 18, wherein:
[0361]
When the size of the first message (msg A) or the size of the second message (msg3) is greater than that set by the group A size threshold parameter (ra-Msg3SizeGroupA) in the four-step random access configuration information When the value is set, make sure to use preamble group B, otherwise make sure to use preamble group A.
[0362]
20. The method according to appendix 16, wherein the determining the preamble group used in the four-step random access procedure includes:
[0363]
In the case that the two-step random access process is triggered by the uplink data channel,
[0364]
Determine the preamble group (A Or B).
[0365]
21. The method as described in Supplement 20, wherein:
[0366]
When the media access control layer protocol data unit (MAC PDU) of the second message (msg3) is greater than the value set by the group A size threshold parameter (ra-Msg3SizeGroupA) of the four-step random access configuration information , Determine to use preamble group B, otherwise determine to use preamble group A.
[0367]
22. The method according to appendix 16, wherein the determining the preamble group used in the four-step random access procedure includes:
[0368]
In the case that the two-step random access process is triggered by the uplink data channel,
[0369]
According to the current path loss, the preamble group (A or B) used in the four-step random access process is determined.
[0370]
23. The method as described in Supplement 22, wherein:
[0371]
When the current path loss is less than the preset path loss threshold, the preamble group B is determined to be used, otherwise, the preamble group B is determined to be used. 24. The method as described in Supplement 12, wherein:
[0372]
The initiating non-competitive random access procedure further includes:
[0373]
Selecting an uplink transmission resource for transmitting the preamble of the non-contention random access when the two-step random access is not completed;
[0374]
The initiation of the four-step random access procedure further includes:
[0375]
When the two-step random access is not completed, the uplink transmission resource for transmitting the preamble of the four-step random access is selected.
[0376]
25. The method according to appendix 24, wherein the selecting an uplink transmission resource for transmitting the preamble of the non-contention random access when the two-step random access is not completed includes:
[0377]
According to the synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) selected from the non-competitive random access candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) or the non-competitive random access candidate channel state The channel state information reference signal (CSI-RS) selected in the information reference signal (CSI-RS), when the two-step random access is not completed, select the physical random access channel opportunity to send the preamble of the non-competitive random access (PRACH occasion).
[0378]
26. The method as described in Supplement 25, wherein:
[0379]
If SSB is selected, the physical random access channel (PRACH) transmission opportunity configuration parameter (ra-ssb-OccasionMaskIndex) in the non-contention random access configuration information corresponding to the SSB indicates the allowed preamble transmission opportunity Select the next available physical random access channel (PRACH) transmission opportunity from the set;
[0380]
If the CSI-RS is selected, the physical random access channel (PRACH) corresponding to the CSI-RS in the non-contention random access configuration information is the allowed preamble identified by the configuration parameter (ra-OccasionList) In the transmission opportunity, the next available physical random access channel (PRACH) transmission opportunity is selected.
[0381]
27. The method according to appendix 24, wherein the selecting an uplink transmission resource for transmitting the preamble of the four-step random access when the two-step random access is not completed includes:
[0382]
Select the next available physical random access channel (PRACH) transmission opportunity from the set of allowed preamble transmission opportunities identified by the preamble transmission opportunity configuration parameter in the four-step random access configuration information as the transmission opportunity in the two-step random access When not completed, the physical random access channel (PRACH) transmission opportunity of the preamble of the four-step random access is sent.
[0383]
28. The method according to Supplement 24, wherein the initiating a non-competitive random access process or a four-step random access process further includes:
[0384]
Calculating the target received power of the random access preamble; and
[0385]
According to the target received power and path loss of the random access preamble, the transmission power of the random access preamble is calculated.
[0386]
29. The method according to appendix 28, wherein the calculating the target received power of the random access preamble comprises:
[0387]
According to the target received power parameter of the random access preamble (preambleReceivedTargetPower), the first target received power offset value (DELTA_PREAMBLE), the power ramp-up count value of the random access preamble (PREAMBLE_POWER_RAMPING_COUNTER), and the random access The power ramp-up step factor (PREAMBLE_POWER_RAMPING_STEP) of the preamble is used to calculate the target received power of the random access preamble.
[0388]
30. The method as described in Supplement 29, wherein:
[0389]
The target received power of the random access preamble is also calculated according to the second target received power offset value (delta_fallback_TargetPower); or,
[0390]
The target received power of the random access preamble is also calculated according to the target received power climb step offset value (delta_fallback_step).
[0391]
31. The method as described in Supplement 30, wherein:
[0392]
The second target received power offset value (delta_fallback_TargetPower) is a preset fixed value, or is related to the ramp rate of the target received power of the preamble of the uncompleted two-step random access.
[0393]
32. The method according to any one of Supplementary Notes 29 to 31, wherein:
[0394]
The initial value of the power ramp-up count value (PREAMBLE_POWER_RAMPING_COUNTER) of the random access preamble is:
[0395]
Preset initial value; or
[0396]
The preamble power climb count value of the unfinished two-step random access.
[0397]
33. The method according to Supplement 28, wherein the initiating a non-competitive random access process or a four-step random access process further includes:
[0398]
According to the selected random access preamble, the uplink transmission resources of the random access preamble, and the calculated transmission power of the random access preamble, the non-contention is sent when the two-step random access is not completed Random access preamble or four-step random access preamble.
[0399]
34. A random access method applied to network equipment, the method comprising:
[0400]
Send to the terminal device non-competitive random access configuration information for the terminal device to initiate a non-competitive random access procedure when the two-step random access procedure is not completed, and/or to indicate that the terminal device has not completed the non-competitive random access procedure. In the two-step random access process, the first instruction to initiate a non-competitive random access process; or,
[0401]
The four-step random access configuration information for the terminal device to initiate the four-step random access process when the two-step random access process is not completed is sent to the terminal device, and/or is used to indicate that the terminal device does not complete the two-step random access process. The second instruction for initiating a four-step random access process during a random access process.
[0402]
35. The method as described in Supplement 34, wherein:
[0403]
The first instruction is sent through an RRC message, and/or a physical downlink control channel (PDCCH) instruction of the physical layer, and/or a random access response message of the medium access control (MAC) layer.
[0404]
36. The method as described in Supplement 34, wherein:
[0405]
The second indication is sent through an RRC message and/or a random access response message of a medium access control (MAC) layer.
[0406]
37. The method according to Supplement 35 or 36, wherein:
[0407]
The random access response message of the MAC layer does not carry contention resolution information and/or does not carry an uplink transmission authorization.
[0408]
38. The method according to any one of Supplementary Notes 34 to 37, wherein the configuration information of the non-contention random access at least includes:
[0409]
The configuration information of the candidate SSB for non-competitive random access, and the configuration information of the preamble corresponding to the candidate SSB; or
[0410]
The configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the configuration information of the preamble corresponding to the channel state information reference signal (CSI-RS) and the transmission opportunity of the preamble Configuration information.
[0411]
39. The method as described in Supplement 34, wherein:
[0412]
The configuration information of the non-contention random access is sent through the RRC message, and/or the physical downlink control channel (PDCCH) instruction of the physical layer, and/or the random access response message of the medium access control (MAC) layer.
[0413]
40. The method according to any one of Supplementary Notes 34 to 37, wherein:
[0414]
The configuration information of the four-step random access is sent through system broadcast information.
[0415]
41. The method according to Supplement 34, wherein the two-step random access procedure is not completed, which refers to at least one of the following situations:
[0416]
The terminal device does not receive a random access response within the random access response receiving window after sending the first message (MsgA) of the two-step random access process;
[0417]
The random access contention resolution in the two-step random access process is unsuccessful;
[0418]
The number of times (PREAMBLE_TRANSMISSION_COUNTER) that the terminal device sends two random access preambles (PREAMBLE_TRANSMISSION_COUNTER) reaches the maximum threshold;
[0419]
The power of the terminal device sending the two-step random access preamble and/or the power of the physical uplink shared channel (PUSCH) reaches the maximum threshold (Pcmax).
Claims
[Claim 1]
A random access device applied to a terminal device, the device includes: a first control unit that controls the terminal device to initiate a two-step random access process; and a second control unit that performs a two-step random access process When it is not completed, the terminal device is controlled to initiate a non-contention random access process or a four-step random access process.
[Claim 2]
The apparatus according to claim 1, wherein the incomplete two-step random access procedure refers to at least one of the following situations: after sending the first message (MsgA) of the two-step random access procedure, The random access response is not received within the random access response receiving window; the random access contention resolution in the two-step random access process is unsuccessful; the number of times of sending the two-step random access preamble reaches the maximum threshold Value: The power of the two-step random access preamble and/or the power of the physical uplink shared channel (PUSCH) reaches the maximum threshold.
[Claim 3]
The apparatus according to claim 1, wherein the initiating a non-competitive random access process or a four-step random access process comprises: deciding to initiate a non-competitive random access procedure while storing configuration information of the non-competitive random access Random access process, or the terminal device decides to initiate a four-step random access process; or when the configuration information for non-competitive random access is saved, a non-competitive random access process is initiated according to the first instruction of the network device Or, the terminal device initiates a four-step random access procedure according to the second instruction of the network device.
[Claim 4]
The apparatus according to claim 3, wherein the configuration information of the non-contention random access at least comprises: the configuration information of the candidate synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) of the non-contention random access, And the configuration information of the preamble corresponding to the candidate synchronization signal/physical broadcast channel block; or the configuration information of the candidate channel state information reference signal (CSI-RS) for non-competitive random access, and the channel state information reference signal ( CSI-RS) corresponding to the configuration information of the preamble and the configuration information of the transmission opportunity of the preamble.
[Claim 5]
The apparatus according to claim 3, wherein the second control unit controls the terminal device to receive a radio resource control (RRC) message and/or a random access response message of a medium access control (MAC) layer The second instruction.
[Claim 6]
The apparatus according to claim 1, wherein said initiating a non-contention random access process comprises: initializing a non-competition random access process when the two-step random access is not completed; said initiating a four-step random access process The entry process includes: Performing the initialization of the four-step random access process when the two-step random access is not completed.
[Claim 7]
7. The apparatus according to claim 6, wherein, when the four-step random access procedure is initialized when the two-step random access is not completed, the configured four-step random access parameter is from the received four-step random access It is obtained from the configuration information, and/or from the parameters reused with the original competing random access parameters.
[Claim 8]
7. The apparatus according to claim 6, wherein said initiating the non-contention random access process further comprises: determining the preamble of the non-contention random access to be sent when the two-step random access is not completed; said initiating The four-step random access process also includes: determining the preamble of the four-step random access to be sent when the two-step random access is not completed.
[Claim 9]
8. The apparatus according to claim 8, wherein the determining the four-step random access preamble to be sent when the two-step random access is not completed comprises: measuring a synchronization signal/physical broadcast channel block (SS) sent by a network device /PBCH Block, SSB) the received power of the synchronization reference signal (SS-RS), select the synchronization signal/physical broadcast channel block (SS/PBCH Block, SSB) used for the four-step random access; and according to the selection The SSB determines the four-step random access preamble to be sent.
[Claim 10]
The apparatus according to claim 9, wherein the selecting the four-step random access preamble to be transmitted according to the selected SSB comprises: determining a preamble group used in the four-step random access process; and A preamble is randomly selected from the preamble set of the determined preamble group corresponding to the selected SSB as the four-step random access preamble to be transmitted, wherein each preamble in the preamble set of the preamble group is selected The probability of the code is the same.
[Claim 11]
8. The apparatus according to claim 8, wherein the initiating a non-competitive random access process further comprises: selecting an uplink transmission resource for transmitting the preamble of the non-competitive random access when the two-step random access is not completed The initiating the four-step random access procedure further includes: selecting an uplink transmission resource for transmitting the preamble of the four-step random access when the two-step random access is not completed.
[Claim 12]
The apparatus according to claim 11, wherein the selecting an uplink transmission resource for transmitting the preamble of the four-step random access when the two-step random access is not completed comprises: configuring the four-step random access The next available physical random access channel (PRACH) transmission opportunity is selected from the set of allowed preamble transmission opportunities identified by the preamble transmission opportunity configuration parameter in the information as the four-step random access when the two-step random access is not completed. The physical random access channel (PRACH) transmission opportunity of the accessed preamble.
[Claim 13]
The apparatus of claim 11, wherein said initiating a non-contention random access process or a four-step random access process further comprises: calculating the target received power of the random access preamble; and according to the random access The target received power and path loss of the preamble, and the transmission power of the random access preamble is calculated.
[Claim 14]
The apparatus according to claim 13, wherein the calculating the target received power of the random access preamble comprises: according to the target received power parameter of the random access preamble (preambleReceivedTargetPower), the first target received power offset The shift value (DELTA_PREAMBLE), the power ramping count value of the random access preamble (PREAMBLE_POWER_RAMPING_COUNTER), and the power ramping step factor (PREAMBLE_POWER_RAMPING_STEP) of the random access preamble, and the target reception of the random access preamble is calculated power.
[Claim 15]
The apparatus according to claim 14, wherein the target received power of the random access preamble is further calculated according to the second target received power offset value (delta_fallback_TargetPower); or, the step offset value is also climbed according to the target received power (delta_fallback_step) Calculate the target received power of the random access preamble.
[Claim 16]
The apparatus according to claim 15, wherein the second target received power offset value (delta_fallback_TargetPower) is a preset fixed value, or is the same as the target received power of the preamble of the uncompleted two-step random access The climb rate is related.
[Claim 17]
The apparatus according to claim 14, wherein the initial value of the power ramp-up count value (PREAMBLE_POWER_RAMPING_COUNTER) of the random access preamble is: a preset initial value; or the preamble of the uncompleted two-step random access Code power climb count value.
[Claim 18]
The apparatus of claim 13, wherein the initiating a non-competitive random access process or a four-step random access process further comprises: according to the selected random access preamble, the random access preamble When the two-step random access is not completed, the non-contention random access preamble or the four-step random access preamble is sent.
[Claim 19]
A random access device, which is applied to a network device, and includes: a third control unit, which is used to control the network device to send to the terminal device for the terminal device to initiate non-transmission when the two-step random access process is not completed. The non-competitive random access configuration information of the competing random access process, and/or the first instruction used to instruct the terminal device to initiate the non-competitive random access process when the two-step random access process is not completed; or, The fourth control unit is configured to control the network device to send to the terminal device four-step random access configuration information for the terminal device to initiate the four-step random access process when the terminal device has not completed the two-step random access process, and/or A second instruction used to instruct the terminal device to initiate a four-step random access process when the two-step random access process is not completed.
[Claim 20]
A communication system having a terminal device and a network device, wherein the terminal device has the random access device according to any one of claims 1 to 18, and the network device has the device according to claim 19 Random access device.