Title of invention: Dispersion unit, central unit, and methods thereof
Technical field
[0001]
　The present disclosure relates to wireless communication systems, in particular to the use of one or more bandwidth parts set within one carrier band.
Background technology
[0002]
　The 3rd Generation Partnership Project (3GPP) is working on standardization of the 5th generation mobile communication system (5G) for introduction after 2020. 5G is realized by a combination of continuous improvement / evolution of LTE and LTE-Advanced and innovative improvement / development by introducing a new 5G air interface (new Radio Access Technology (RAT)). Will be done. The new RAT is, for example, a frequency band higher than the frequency band (eg, 6 GHz or less) targeted by the continuous development of LTE / LTE-Advanced, such as a centimeter wave band of 10 GHz or more and a millimeter of 30 GHz or more. Supports wave bands.
[0003]
　As used herein, the 5th generation mobile communication system is referred to as a 5G system, or Next Generation (NextGen) System (NG System). The new RAT for 5G System is called New Radio (NR), 5G RAT, or NG RAT. The new Radio Access Network (RAN) for the 5G System is called NextGen RAN (NG-RAN) or 5G-RAN. The new base station in NG-RAN is called gNodeB (gNB). The new core network for the 5G System is called the 5G Core Network (5GC) or NextGen Core (NG Core). The wireless terminal (User Equipment (UE)) connected to the 5G System is called 5G UE, NextGen UE (NG-UE) or simply UE.
[0004]
　As used herein, the term "LTE" includes improvements and developments in LTE and LTE-Advanced to enable interworking with 5G Systems, unless otherwise noted. Improvements and developments of LTE and LTE-Advanced for interworking with 5G Systems are called LTE-Advanced Pro, LTE +, or enhanced LTE (eLTE). In addition, “Evolved Packet Core (EPC)”, “Mobility Management Entity (MME)”, “Serving Gateway (S-GW)”, and “Packet Data Network (PDN) Gateway (P-GW)” as used herein. ) ”And other terms relating to LTE networks or logical entities include these improvements and developments to enable interworking with 5G Systems, unless otherwise noted. Improved EPC, MME, S-GW, and P-GW include, for example, enhanced EPC (eEPC), enhanced MME (eMME), enhanced S-GW (eS-GW), and enhanced P-GW (eP-GW). ).
[0005]
　In LTE and LTE-Advanced, for quality of service (QoS) and packet routing, bearers for each QoS class and each PDN connection are RAN (ie, Evolved Universal Terrestrial RAN (E-UTRAN)) and core network (ie, Used in both EPC). That is, in the Bearer-based QoS (or per-bearer QoS) concept, one or more Evolved Packet System (EPS) bearers are configured between the UE and the P-GW in the EPC, and multiple Evolved Packet System (EPS) bearers with the same QoS class. Service Data Flows (SDFs) are transferred through a single EPS bearer that satisfies these QoS.
[0006]
　In contrast, in 5G Systems, radio bearers may be used in NG-RAN, but bearers are not used within 5GC and in the interface between 5GC and NG-RAN. Specifically, QoS flows are defined instead of EPS bearer, and one or more SDFs are mapped to one or more QoS flows. The QoS flow between the 5G UE and the user plane termination entity in NG Core (ie, the entity equivalent to P-GW in EPC) corresponds to the EPS bearer in the EPS Bearer-based QoS concept. The QoS flow corresponds to the finest granularity of packet forwarding and treatment within the 5G system. That is, the 5G System adopts the Flow-based QoS (or per-flow QoS) concept instead of the Bearer-based QoS concept. In the Flow-based QoS concept, QoS is handled on a per-QoS flow basis. The association between the 5G UE and the data network is called the PDU session. PDU session is a term equivalent to LTE and LTE-Advanced PDN connection. Multiple QoS flows can be configured within a PDU session. The 3GPP specification specifies the 5G QoS Indicator (5QI), which is the equivalent of LTE QCI, for the 5G System.
[0007]
　Figure 1 shows the basic architecture of a 5G system. The architecture shown in FIG. 1 is an architecture called "Standalone NR (in NextGen System)" or "Option 2". The UE establishes one or more Signaling Radio Bearers (SRBs) and one or more Data Radio Bearers (DRBs) with the gNB. 5GC and gNB establish a control plane interface and a user plane interface for the UE. The control plane interface between 5GC and gNB (ie, RAN) is called the NG-c interface, which transfers Non-Access Stratum (NAS) information and controls information between 5GC and gNB (eg, N2 AP Information). Used for Element). The user plane interface between 5GC and gNB (ie, RAN) is called the NG-u interface and is used to forward one or more QoS flows packets within the UE's PDU session.
[0008]
　NR supports the use of different radio parameter sets in multiple frequency bands. Each radio parameter set is called "numerology". OFDM numerology for Orthogonal Frequency Division Multiplexing (OFDM) systems includes, for example, subcarrier spacing, system bandwidth, Transmission Time Interval (TTI) length, and sub. Includes subframe duration, cyclic prefix length, and symbol duration. The 5G system provides various types of services with different service requirements, such as enhanced Mobile Broad Band (eMBB), Ultra Reliable and Low Latency Communication (URLLC), and multi-connection M2M communication (massive). Supports, including Machine Type Communication: mMTC). The choice of Numerology depends on the service requirements.
[0009]
　NR supports a wider channel bandwidths (eg, 100s of MHz) than that of LTE. One channel band (ie, BW Channel ) is a radio frequency band (RF bandwidth) that supports one NR carrier. The channel bandwidth is also called the system bandwidth. LTE supports channel bandwidths up to 20 MHz, while 5G NR supports channel bandwidths up to, for example, 500 MHz.
[0010]
　In order to efficiently support multiple 5G services, such as wideband services such as eMBB and narrowband services such as the Internet of Things (IoT), it is preferable to be able to multiplex these multiple services on a single channel band. .. In addition, if all 5G UEs must support transmission and reception over the entire channel bandwidth, this is the low cost and low power consumption of UEs for narrowband IoT services. May hinder. Therefore, 3GPP allows one or more bandwidth parts (BWPs) to be set within the carrier band (ie, channel band or system band) of each NR component carrier. The bandwidth part is also called the carrier bandwidth part. Multiple BWPs may be used for frequency division multiplexing (FDM) of different numbers (eg, subcarrier spacing (SCS)). For example, multiple BWPs may have different SCSs and different bandwidths.
[0011]
　2 and 3 show examples of using BWP. In the example shown in FIG. 2, the channel bandwidth of one component carrier is divided into BWP # 1 and BWP # 2, and these two BWPs are used for FDM with different numbers (eg, different subcarrier spacing). .. In the example shown in FIG. 3, a narrow band BWP # 1 is arranged in the channel band of one component carrier, and a narrow band BWP # 2 is further arranged in the channel band of one component carrier. When BWP # 1 or BWP # 2 is activated for a UE, the UE can reduce power consumption by not receiving and transmitting outside the active BWP (but within the channel bandwidth).
[0012]
　One bandwidth part (BWP) is composed of frequency-consecutive and contiguous physical resource blocks (PRBs). The bandwidth of one BWP is at least as large as the synchronization signal (SS) / physical broadcast channel (PBCH) block bandwidth. BWP may or may not include SS / PBCH block (SSB).
[0013]
　The BWP configuration includes, for example, numerology, frequency location, and bandwidth (the number of eg, PRBs). Common PRB indexing is used for the downlink (DL) BWP configuration at least in the Radio Resource Control (RRC) connected state to specify the frequency location. Specifically, the offset from PRB 0 to the lowest PRB of the SSB accessed by the UE is set by higher layer signaling. The reference point “PRB 0” is common to all UEs that share the same wideband component carrier.
[0014]
　One SS / PBCH block contains the basic signals required for idle UE, such as NR synchronization signals (NR-SS) and NR physical broadcast channel (NR-PBCH). NR-SS is used by the UE to get DL synchronization. A Reference Signal (RS) is sent in the SS / PBCH block to enable Radio Resource Management (RRM) measurement (eg, RSRP measurement) to the idle UE. The RS may be the NR-SS itself or an additional RS. The NR-PBCH broadcasts a portion of the minimum system information (minimum SI) (eg, Master Information Block (MIB)). The remaining minimum SI (remaining minimum SI (RMSI)) is transmitted via the Physical Downlink Shared Channel (PDSCH).
[0015]
　The network can transmit multiple SS / PBCH blocks within the channel bandwidth of one broadband component carrier. In other words, SS / PBCH blocks may be transmitted in multiple BWPs within the channel band. In the first plan, all SS / PBCH blocks in one broadband carrier correspond to the same physical-layer cell identity (NR-SS (eg, primary SS (PSS)) and secondary SS (SSS). ))based on. In the second option, different SS / PBCH blocks in one broadband carrier may be based on NR-SS corresponding to different physical-layer cell identifiers.
[0016]
　From the UE perspective, cells are associated with one SS / PBCH block. Therefore, for the UE, each serving cell has one associated SS / PBCH block (single associated SS / PBCH block) in frequency. Each serving cell is a carrier aggregation (CA) and dual connectivity (DC) primary cell (PCell), a DC primary secondary cell (PSCell), or a CA and DC secondary cell (SCell). Such an SSB is called a cell defining SS / PBCH block. The Cell defining SS / PBCH block has an associated RMSI. The Cell defining SS / PBCH block serves as a time reference or timing reference for the serving cell. Also, the Cell defining SS / PBCH block is used for SS / PBCH block (SSB) based RRM Measurements. Cell defining SS / PBCH block is "synchronous reconfiguration" for PCell / PSCell (eg, reconfiguration of radio resource configuration information without handover using RRC Reconfiguration procedure) and "SCell release /" for SCell. It can be changed by "add".
[0017]
　One or more BWP configurations for each component carrier are quasi-statically signaled to the UE. Specifically, for each UE-specific serving cell, one or more DL BWPs (eg, up to four DL BWPs) and one or more UL BWPs (eg, up to four UL BWPs) are dedicated RRC. Can be configured for UE by message. One or more DL BWPs and one or more UL BWPs set in the UE are referred to as "DL BWP set" and "UL BWP set", respectively.
[0018]
　Each of one or more BWPs (ie, BWP set) set in the UE can be activated and deactivated. Activated BWP is called "active BWP". That is, the UE receives a signal at any time (at a given time) on one or more of the configured DL BWP sets of activated DL BWP. Similarly, the UE sends a signal at any time (at a given time) on one or more of the configured UL BWP sets of activated UL BWP. In the current specification, only one DL BWP and only one UL BWP are activated at any time (at a given time).
[0019]
　BWP activation / deactivation is determined by a lower layer (eg, Physical (PHY) layer or Medium Access Control (MAC) layer) rather than the RRC layer. Switching of Active BWP is performed by, for example, Downlink Control Information (DCI) (eg, scheduling DCI) transmitted on the NR Physical Downlink Control Channel (PDCCH). In other words, the deactivation of the current active BWP and the activation of the new active BWP may be done by the DCI of the NR PDCCH. The network can activate / deactivate the BWP, for example according to the data rate or the numerology required by the service, and can dynamically switch the active BWP for the UE.
[0020]
　The first BWP (ie, initial active BWP) to stay when the UE accesses each serving cell (when transitioning from ie, Idle mode to Connected mode) is called the "initial BWP". The initial BWP includes at least DL BWP and may include UL BWP (if the serving cell is uplinked). The initial BWP may be referred to as the default BWP, reference BWP, primary BWP, anchor BWP, or master BWP. The BWP set set in the UE always includes the initial BWP.
[0021]
　The initial BWP is always set to Common Search Space. BWPs other than the initial BWP may or may not have the Common Search Space set. The Common Search Space is a subset of resources (ie, PDCCH Search Space) in which the UE performs blind decoding to search for PDCCH data (ie, DCI). In 5G systems, like LTE, PDCCH Search Space includes Common Search Space and UE-specific Search Space. The UE-specific search space is individually set for each UE via RRC signaling. On the other hand, all UEs accessing the serving cell know the extent or range of the Common Search Space. The NR Common Search Space is used to broadcast system information and paging, random access channel (RACH) responses, etc. The NR Common Search Space includes “Type0-PDCCH common search space”. In Type0-PDCCH common search space, PDCCH (ie, DCI) scrambled by System Information Radio Network Temporary Identifier (SI-RNTI) is transmitted to enable UE to receive System Information Block Type 1 (SIB1). To.
[0022]
　3GPP considers that if the UE's active DL BWP does not have a Common Search Space (CSS) configured, the UE does not have to receive system information updates (SI updates) broadcast (eg, non). See Patent Document 1). In this case, the network (NG-RAN) sends the updated SI to the UE staying in the active DL BWP for which the Common Search Space is not set via dedicated signaling (eg, RRC Reconfiguration message). You may send it.
[0023]
　Next, the cloud RAN (C-RAN) deployment of NG-RAN will be described. FIG. 4 is a diagram showing the overall architecture of NG-RAN (see Non-Patent Document 2). The NG-RAN consists of a set of gNBs connected to the 5GC via the NG interface. gNBs can be connected via the Xn interface. As shown in FIG. 4, gNB may be composed of gNB Central Unit (gNB-CU) and one or more gNB Distributed Units (gNB-DUs). gNB-CU and gNB-DU are connected via the F1 interface. gNB-CU is a logical node that hosts gNB's RRC, Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols (or gNB's RRC and PDCP protocols). The gNB-DU is a logical node that hosts the gNB's Radio Link Control (RLC), MAC, and PHY layers.
Prior art literature
Non-patent literature
[0024]
Non-Patent Document 1: CATT, “CSS configuration for SI acquisition in non-initial BWP [C077]”, R2-1810493, 3GPP TSG-RAN WG2 Meeting # AH-1807, Montreal, Canada, July 2nd --July 6th 2018
Non-Patent Reference 2: 3GPP TS 38.401 V15.2.0 (2018-06), “3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NG-RAN; Architecture description (Release 15)”, June 2018
Outline of the invention
Problems to be solved by the invention
[0025]
　The inventors examined the case where the gNB-CU transmits SI updates to the UE via dedicated signaling. gNB-CU sends the updated SI to UEs staying in active DL BWP for which Common Search Space is not set via individual signaling. Therefore, it is preferable that gNB-CU can know UEs staying in active DL BWP for which Common Search Space is not set.
[0026]
　However, as mentioned above, changes in active BWP are made, for example, by DCI in NR PDCCH. Therefore, in some implementations, gNB-DU may determine the active BWP change and send the DCI for the active BWP change to the UE. In this case, gNB-CU may not know which of the DL BWP sets configured on the UE is the active DL BWP. In other words, gNB-CU may not know the active DL BWP of each UE. In addition to this, in some implementations, gNB-DU may decide whether to set the Common Search Space to non-initial (non-initial BWP). In this case, gNB-CU may not know if a Common Search Space is set for each non-initial BWP in the DL BWP set set in the UE.
[0027]
　Therefore, gNB-CU may not be able to know the UEs staying in the active DL BWP for which the Common Search Space is not set. Note that gNB-CU knows UEs staying in active DL BWP for which Common Search Space is not set, in addition to or for other purposes in place of sending SI updates. It may be preferable to be able to.
[0028]
　One of the objectives to be achieved by the embodiments disclosed herein is to know the radio terminals (eg, UEs) staying in the active bandwidth part where the Common Search Space is not set. To provide equipment, methods, and programs that contribute to enabling the central unit (eg, gNB-CU) of eg, gNB). It should be noted that this object is only one of the purposes that the plurality of embodiments disclosed herein seek to achieve. Other objectives or issues and novel features will be apparent from the description or accompanying drawings herein.
Means to solve problems
[0029]
　In the first aspect, the base station distribution unit comprises at least one memory and at least one processor coupled to said at least one memory. The at least one processor is configured to transmit at least one list of terminals to the central unit of the base station. The list of at least one terminal indicates at least one of the following:
(a) a plurality of wireless terminals in which a common search space is not set in each activation downlink Bandwidth Part (BWP);
(b) each Multiple wireless terminals for which at least a Search Space (SS) for receiving system information is not set in the activated downlink BWP;
(c) It is necessary to receive updated system information via individual signaling for each wireless terminal. There are multiple wireless terminals;
(d) multiple wireless terminals for which each activated downlink BWP is a non-initial downlink BWP; and
(e) multiple wireless terminals receiving on each downlink BWP.
[0030]
　In the second aspect, the central unit of the base station comprises at least one memory and at least one processor coupled to said at least one memory. The at least one processor is configured to receive at least one list of terminals from the distributed unit of the base station. The at least one terminal list is similar to that of the first aspect.
[0031]
　In a third aspect, the method in a base station distributed unit comprises transmitting at least one terminal list to the base station central unit. The at least one terminal list is similar to that of the first aspect.
[0032]
　In a fourth aspect, the method in the central unit of a base station comprises receiving at least one terminal list from the distributed unit of the base station. The at least one terminal list is similar to that of the first aspect.
[0033]
　In a fifth aspect, the base station distribution unit comprises at least one memory and at least one processor coupled to said at least one memory. The at least one processor is configured to send a message to the central unit of the base station containing an information element indicating a change in the activation downlink Bandwidth Part (BWP) of the radio terminal.
[0034]
　In a sixth aspect, the central unit of the base station comprises at least one memory and at least one processor coupled to said at least one memory. The at least one processor is configured to receive a message from the base station's distributed unit that includes an information element indicating a change in the activation downlink BWP of the radio terminal.
[0035]
　In a seventh aspect, the method in a base station distributed unit comprises transmitting a message containing an information element indicating a change in the activation downlink BWP of the radio terminal to the central unit of the base station.
[0036]
　In an eighth aspect, the method in the central unit of a base station comprises receiving a message from the distributed unit of the base station containing an information element indicating a change in the activation downlink BWP of the radio terminal.
[0037]
　In the ninth aspect, the program provides a group of instructions (software code) for causing the computer to perform the method according to the third, fourth, seventh, or eighth aspect described above when loaded into the computer. Including.
Effect of the invention
[0038]
　According to the above aspect, the central unit (eg, gNB-CU) of the base station (eg, gNB) knows the wireless terminals (eg, UEs) staying in the active bandwidth part where the Common Search Space is not set. ) Can be provided with devices, methods, and programs that contribute to enabling.
A brief description of the drawing
[0039]
[Fig. 1] Fig. 1 shows the basic architecture of the 5G System.
[Fig. 2] Fig. 2 is a diagram showing a usage example of Bandwidth part (BWP).
[Fig. 3] Fig. 3 is a diagram showing a usage example of Bandwidth part (BWP).
[Fig. 4] Fig. 4 is a diagram showing the overall architecture of NG-RAN.
FIG. 5 is a diagram showing a configuration example of a wireless communication network according to the first embodiment.
FIG. 6 is a diagram showing a configuration example of a wireless communication network according to the first embodiment.
FIG. 7 is a sequence diagram showing an example of signaling between CU and DU according to the first embodiment.
FIG. 8 is a sequence diagram showing an example of signaling between CU and DU according to the second embodiment.
FIG. 9 is a sequence diagram showing an example of signaling for transmission of updated SI according to a third embodiment.
FIG. 10 is a diagram showing an example of a format of an F1 AP message (eg, BWP INFORMATION message) according to a third embodiment.
FIG. 11 is a sequence diagram showing an example of signaling between CU and DU according to the fourth embodiment.
FIG. 12 is a diagram showing an example of a format of an F1AP message (eg, UE CONTEXT MODIFICATION REQUIRED message) according to a fourth embodiment.
FIG. 13 is a block diagram showing a configuration example of a central node (eg, gNB-CU) according to some embodiments.
FIG. 14 is a block diagram showing a configuration example of distributed nodes (eg, gNB-DU) according to some embodiments.
Mode for carrying out the invention
[0040]
　Hereinafter, specific embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are designated by the same reference numerals, and duplicate explanations are omitted as necessary for the sake of clarity of explanation.
[0041]
　The plurality of embodiments described below may be implemented independently or in combination as appropriate. These plurality of embodiments have novel features that differ from each other. Therefore, these plurality of embodiments contribute to solving different purposes or problems, and contribute to different effects.
[0042]
　The plurality of embodiments shown below will be described with the 3GPP 5G system as the main subject. However, these embodiments may be applied to other wireless communication systems.
[0043]

　FIG. 5 shows a configuration example of a wireless communication network according to the present embodiment. The wireless communication network according to the present embodiment includes a gNB Central Unit (gNB-CU) 1 and one or more gNB Distributed Units (gNB-DUs) 2. An interface 501 connects the gNB-CU1 and each gNB-DU2. Interface 501 is an F1 interface. UE3 is connected to at least one gNB-DU2 via at least one air interface 502.
[0044]
　As shown in FIG. 6, the gNB-CU 1 may include a Control Plane (CP) Unit (gNB-CU-CP) 11 and one or more User Plane (UP) Unit (gNB-CU-UP) 12. Good. In this case, the gNB-CU-CP11 is connected to the gNB-CU-UP12 via the control plane interface 601 (ie, E1 interface). Further, the gNB-CU-CP11 is connected to the gNB-DU2 via the control plane interface 602 (ie, F1-C interface). The gNB-CU-UP12 is connected to the gNB-DU2 via the user plane interface 603 (ie, F1-U interface).
[0045]
　gNB-CU1 may be a logical node hosting gNB's RRC, SDAP, and PDCP protocols (or gNB's RRC and PDCP protocols). The gNB-DU2 may be a logical node hosting the gNB's RLC, MAC, and PHY layers. In such a functional arrangement, gNB-DU2 may determine the BWP set set for UE3, and gNB-DU2 may notify the associated gNB-CU1 of the BWP set setting for UE3. In addition, gNB-DU2 may determine the (first) active BWP (s) of UE3 and notify the associated gNB-CU1 of this. Alternatively, gNB-CU1 may determine the BWP set set for UE3 and gNB-CU1 may notify the associated gNB-DU2 of the BWP set setting for UE3. Further or instead, gNB-CU1 may determine the (first) active BWP (s) of UE3 and notify the associated gNB-DU2 of this. In any of these cases, gNB-DU2 may change the active BWP (s) of UE3. That is, gNB-DU2 may determine activation / deactivation of BWP (s). Further, gNB-DU2 may notify gNB-CU1 of the changed BWP (s) information. The information on the BWP (s) after the change may be, for example, information indicating whether each BWP is activated or deactivated, or information indicating a difference from the information on the BWP (s) before the change. There may be.
[0046]
　FIG. 7 shows process 700, which is an example of signaling between gNB-CU1 and gNB-DU2. In step 701, gNB-DU2 sends an F1 Application Protocol message. The name of the message is not limited to this, but may be, for example, a BWP INFORMATION message. The message includes at least one terminal list (ie, UE list). The at least one UE list indicates at least one of the following:
(a) UEs that do not have a Common Search Space (CSS) configured in
each active DL BWP ; (b) at least SI in each active DL BWP
UEs for which Search Space (SS) is not set to receive; (c) UEs that need to receive updated SI via individual signaling for each UE (or updated SI transmits with individual signaling for each UE) UEs that need to be, or UEs that gNB-CU1 needs to send updated SI with individual signaling per UE);
(d) UEs where each active DL BWP is a non-initial DL BWP; and
(e) UEs received on each DL BWP.
[0047]
　By receiving from gNB-DU2 a UE list indicating UEs that do not have CSS set in each active DL BWP, gNB-CU1 knows the UEs that are staying in the active DL BWP that does not have CSS set. Can be done. This allows the gNB-CU1 to determine, for example, UEs that require the transmission of updated SI via individual signaling (eg, RRC Reconfiguration messages). In other words, this allows gNB-DU2 to be informed of UEs that require the transmission of updated SI via individual signaling to gNB-CU1. The UE list is useful, for example, for implementations that determine whether gNB-DU2 sets CSS for non-initial BWP. The UE list may be a list of UEs staying in active DL BWP without CSS. gNB-DU2 selects UEs that are receiving on active DL BWP that does not have CSS set from among UEs that are RRC_Connected in its own cell, and sends a list of selected UEs to gNB-CU1. May be good.
[0048]
　Further or instead, gNB-DU2 sends to gNB-CU1 a list of UEs that do not have at least a Search Space (SS) (SI-SS) configured to receive SI in each active DL BWP. You may. As a result, gNB-CU1 can know the UEs staying in the active DL BWP for which SI-SS is not set. The SI-SS may be included in the CSS or the UE specific Search Space (USS).
[0049]
　By receiving from gNB-DU2 a UE list indicating UEs that need to receive updated SI via individual signaling for each UE, gNB-CU1 can directly know such UEs. This allows the gNB-CU1 to determine, for example, UEs that require the transmission of updated SI via individual signaling. The UE list is useful, for example, for implementations that determine whether gNB-DU2 sets CSS for non-initial BWP. Even if gNB-DU2 selects UEs received by active DL BWP that does not have CSS set from UEs that are RRC_Connected in its own cell and sends a list of selected UEs to gNB-CU1 Good.
[0050]
　By receiving a UE list indicating UEs in which each active DL BWP is a non-initial DL BWP from gNB-DU2, gNB-CU1 can know the UEs staying in the non-initial DL BWP. This allows the gNB-CU1 to determine, for example, UEs that require the transmission of updated SI via individual signaling. The UE list is useful, for example, for implementations where gNB-CU1 determines whether to set CSS for non-initial BWP and directs gNB-DU2 to set CSS for non-initial BWP. In addition, the UE list is also useful for implementations that determine whether gNB-DU2 sets CSS for non-initial BWP. In this implementation, gNB-CU1 may also refer to other information (eg, Cell Group Configuration (CG-Config or CellGroupConfig)) to see if CSS is set for each non-initial BWP. Good. The gNB-DU2 may select the UEs received by the non-initial active DL BWP from the UEs that are RRC_Connected in its own cell, and send a list of the selected UEs to the gNB-CU1.
[0051]
　By receiving a UE list (ie, a list of UEs for each DL BWP) indicating the UEs received on each DL BWP from gNB-DU2, the gNB-CU1 is staying in each DL BWP ie, its active DL BWP can know each DL BWP UEs). This allows the gNB-CU1 to determine, for example, UEs that require the transmission of updated SI via individual signaling. The UE list is useful, for example, for implementations that determine whether gNB-DU2 sets CSS for non-initial BWP. In this implementation, gNB-CU1 may further refer to other information (eg, CG-Config or CellGroupConfig) to know if CSS is set for each non-initial BWP.
[0052]
　Specifically, gNB-CU1 is included in the DU to CU RRC Information Information Element (IE) in the F1AP: UE Context Setup Response message received from gNB-DU2 during the UE Context Setup procedure. You may look at the contents of CellGroupConfig IE. gNB-DU2 can include information about Common Search Space in "CellGroupConfig" IE. Therefore, gNB-CU1 can know whether or not CSS is set by gNB-DU2 for each non-initial BWP by looking at CellGroupConfig IE.
[0053]
　Further, the UE list is also useful for implementations in which gNB-CU1 determines whether to set CSS for non-initial BWP and instructs gNB-DU2 to set CSS for non-initial BWP.
[0054]
　These UE lists may utilize any identifier to distinguish UEs. For example, the identifiers used to distinguish UEs in the UE list are Cell RNTI (C-RNTI), gNB-CU UE F1AP ID, gNB-DU UE F1AP ID, or gNB-CU UE F1AP ID and gNB- It may be a DU UE F1AP ID pair. C-RNTI uniquely identifies the UE (or UE's RRC connection) within the cell for scheduling purposes. The gNB-CU UE F1AP ID uniquely identifies the UE association on the F1 interface within the gNB-CU1. The gNB-DU UE F1AP ID uniquely identifies the UE association on the F1 interface within gNB-DU2.
[0055]
　In some implementations, the gNB-DU2 responds to receiving a first control message (ie, F1AP message) from the gNB-CU1 that includes a System Information Update Notification, as described above. A second control message (ie, F1AP message) containing the UE list may be sent to gNB-CU1. The system information update notification indicates that the system information will be updated in the next modification period. This contributes to promptly notifying the gNB-CU1 from gNB-DU2 that there are UEs that require transmission of the updated SI by individual signaling when the SI is updated by the gNB-CU1. The system information may be, for example, a Warning Notification message of the Public Warning System (PWS), or a warning notification message (eg ETWS primary notification, ETWS secondary) of the Earthquake and Tsunami Warning System (ETWS). It may be notification, or both).
[0056]
　This first control message may be a SYSTEM INFORMATION DELIVERY COMMAND message. Upon receiving the SYSTEM INFORMATION DELIVERY COMMAND message, gNB-DU2 broadcasts the requested system information in CSS. Further, in the present embodiment, the gNB-DU2 transmits a second control message including the above-mentioned UE list to the gNB-CU1. The name of this second control message is not limited to this, but may be, for example, a SYSTEM INFORMATION DELIVERY CONFIRM message.
[0057]
　FIG. 8 shows process 800, which is an example of signaling between gNB-CU1 and gNB-DU2. In step 801 the gNB-CU1 sends a SYSTEM INFORMATION DELIVERY COMMAND message to the gNB-DU2 that includes a system information update notification. In step 802, in response to receiving the SYSTEM INFORMATION DELIVERY COMMAND message, the gNB-DU2 transmits a SYSTEM INFORMATION DELIVERY CONFIRM message including the above-mentioned UE list to the gNB-CU1.
[0058]
　Further or instead, the gNB-DU2 may transmit the above UE list to the gNB-CU1 in response to its own decision to update the system information. This contributes to promptly informing gNB-DU2 of gNB-CU1 that there are UEs that require transmission by individual signaling of the updated SI when the SI is updated by gNB-DU2.
[0059]
　Further or instead, the gNB-DU2 may transmit the above-mentioned UE list to the gNB-CU1 in response to receiving a request for the UE list from the gNB-CU1. This allows the gNB-CU1 to know at any time (at a given time) that there are UEs that require transmission of the updated SI by individual signaling.
[0060]
　As will be understood from the above description, in the present embodiment, the gNB-DU2 is configured to transmit at least one UE list to the gNB-CU1. The at least one UE list indicates at least one of the following:
(a) UEs that do not have a Common Search Space (CSS) configured in
each active DL BWP ; (b) at least SI in each active DL BWP
UEs for which Search Space (SS) is not set to receive; (c) UEs that need to receive updated SI via individual signaling for each UE (or updated SI is transmitted with individual signaling for each UE. UEs that need to be, or UEs that gNB-CU1 needs to send updated SI with individual signaling for each UE);
(d) UEs where each active DL BWP is a non-initial DL BWP; and
(e) each UEs receiving on DL BWP.
　This helps gNB-CU1 to find out which UEs are staying in active DL BWP with no CSS configured. For example, gNB-CU1 can determine UEs that require transmission of updated SI via individual signaling (eg, RRC Reconfiguration message) by referring to this UE list.
[0061]
The
　present embodiment provides details regarding signaling for transmission of updated SI. The configuration example of the wireless communication network according to the present embodiment is the same as the example shown in FIGS. 5 and 6.
[0062]
　FIG. 9 shows procedure 900, which is an example of signaling for the transmission of updated SI. In step 901, gNB-DU2 instructs UE3 via PDCCH (ie, DCI) to change the active DL BWP to a non-initial DL BWP that does not have a Common Search Space (CSS) configured. In step 902, the UE 3 stays in the non-initial DL BWP for which CSS is not set and operates to receive a signal in the non-initial DL BWP.
[0063]
　Steps 903 and 904 are similar to steps 801 and 802 shown in FIG. That is, in step 903, the gNB-CU1 transmits a SYSTEM INFORMATION DELIVERY COMMAND message including the system information update notification to the gNB-DU2. In step 904, in response to receiving the SYSTEM INFORMATION DELIVERY COMMAND message, the gNB-DU2 transmits a SYSTEM INFORMATION DELIVERY CONFIRM message containing the UE list described in the first embodiment to the gNB-CU1.
[0064]
　In step 905, after receiving the UE list, gNB-CU1 transmits the updated SI to one or more UEs 3 via individual signaling (eg, RRC Reconfiguration message) for each UE. Specifically, gNB-CU1 needs to know the UEs staying in the active DL BWP for which CSS is not set by referring to the received UE list, and to send the updated SI via individual signaling. Determine the UEs to be. The RRC Reconfiguration message containing the updated SI is carried from gNB-CU1 to gNB-DU2 on the F1 interface by the DL RRC MESSAGE TRANSFER message and transmitted by gNB-DU2 to UE3.
[0065]
　In step 906, UE3 sends an RRC Reconfiguration Complete message to gNB-CU1. The RRC Reconfiguration Complete message is carried from gNB-DU2 to gNB-CU1 on the F1 interface by the UL RRC MESSAGE TRANSFER message.
[0066]
　According to the procedure of FIG. 9, the gNB-CU1 can determine the UEs staying in the active DL BWP for which CSS is not set, and gives these UEs the updated SI via individual signaling. Can be sent.
[0067]
The
　present embodiment provides details regarding the F1AP message for carrying the UE list described in the first embodiment. The configuration example of the wireless communication network according to the present embodiment is the same as the example shown in FIGS. 5 and 6.
[0068]
　FIG. 10 shows an example of the format of the F1AP message (eg, BWP INFORMATION message) for carrying the UE list described in the first embodiment. The message shown in FIG. 10 is transmitted to gNB-CU1 by gNB-DU2. The F1AP message (eg, BWP INFORMATION message) shown in FIG. 10 includes a BWP list showing all (DL) BWPs. The BWP list includes a UE list (or UE ID list) for each (DL) BWP. In the example of FIG. 10, the UE list (or UE ID list) uses C-RNTI to distinguish UEs. The UE list (or UE ID list) may use another identifier (eg, gNB-CU UE F1AP ID or gNB-DU UE F1AP ID) instead of C-RNTI.
[0069]
　The F1AP message shown in FIG. 10 enables gNB-DU2 to provide gNB-CU1 with a UE list (a list of UEs for each ie, DL BWP) indicating UEs received on each DL BWP. To do.
[0070]

　The configuration example of the wireless communication network according to the present embodiment is the same as the example shown in FIGS. 5 and 6. In the first to third embodiments, an example is shown in which gNB-DU2 provides a UE list to gNB-CU1. These examples described in the first to third embodiments carry out non-UE associated procedures or signaling to send a UE list from gNB-DU2 to gNB-CU1. Use. Therefore, the first to third embodiments can reduce the number of signalings between gNB-CU1 and gNB-DU2 as compared to methods using UE associated procedures or signaling. There are advantages.
[0071]
　However, in some implementations, gNB-DU2 may use UE associated procedures or signaling to notify gNB-CU1 of changes in the active DL BWP of UE3. In this embodiment, the gNB-DU2 sends a message indicating the change of the active DL BWP of the UE3 to the gNB-CU1. The gNB-DU2 may send a message to the gNB-CU1 indicating the change of the active DL BWP of the UE3 in response to the change of the active DL BWP of the UE3. After changing the active DL BWP of UE3, gNB-DU2 may send a message indicating the change of active DL BWP of UE3 to gNB-CU1. Specifically, gNB-DU2 may notify gNB-CU1 that the active DL BWP of UE3 has been changed from the initial BWP to the non-initial DL BWP (particularly, the non-initial DL BWP having no CSS). As a result, gNB-CU1 can know the UEs staying in the active DL BWP for which CSS is not set. This allows the gNB-CU1 to determine, for example, UEs that require the transmission of updated SI via individual signaling.
[0072]
　In some implementations, gNB-DU2 changes UE3's active DL BWP in the UE Context Modification Required procedure initiated by gNB-DU2 when it changes or switches UE3's active DL BWP. A message including an information element indicating (or switching) may be sent to gNB-CU1. Specifically, gNB-DU2 responds by changing the active DL BWP of UE3 from the initial BWP to the non-initial DL BWP (particularly the non-initial DL BWP without CSS), and sends a message containing the information element. It may be transmitted to gNB-CU1. gNB-DU2 may include the information element in the F1AP: UE CONTEXT MODIFICATION REQUIRED message.
[0073]
　The information element may be a BOOLEAN data type variable indicating whether the active DL BWP of UE3 has been changed from the initial DL BWP to the non-initial DL BWP. Alternatively, the information element may be an ENUMERATED type variable indicating that the UE3 active DL BWP does not have CSS. Instead, the information element may be an INTEGER type variable indicating an identifier (eg, BWP ID) of the active DL BWP of UE3.
[0074]
　FIG. 11 shows procedure 1100, which is an example of signaling according to this embodiment. In step 1101, gNB-DU2 transmits a UE CONTEXT MODIFICATION REQUIRED message. The message includes the information elements described in this embodiment.
[0075]
　FIG. 12 shows an example of an F1 message format including the information elements described in this embodiment. The UE CONTEXT MODIFICATION REQUIRED message shown in FIG. 12 is sent by gNB-DU2 to gNB-CU1 to request modification of the UE context. The UE CONTEXT MODIFICATION REQUIRED message shown in FIG. 12 contains a UE switch to BWP information element (IE). As mentioned above, the “UE switch to BWP” IE may be a BOOLEAN data type variable that indicates whether the active DL BWP of UE3 has been changed from DL BWP to non-initial DL BWP. Alternatively, the “UE switch to BWP” IE may be an ENUMERATED type variable indicating that the UE3 active DL BWP does not have CSS.
[0076]
　The UE CONTEXT MODIFICATION REQUIRED message of FIG. 12 may include a BWP-ID information element (IE) instead of the “UE switch to BWP” IE. The “BWP-ID” IE may be an INTEGER type variable indicating an identifier (eg, BWP ID) of the active DL BWP of UE3.
[0077]
　Subsequently, a configuration example of gNB-CU1 and gNB-DU2 according to the above-described plurality of embodiments will be described below. FIG. 13 is a block diagram showing a configuration example of gNB-CU1 according to the above embodiment. The configurations of gNB-CU-CP11 and gNB-CU-UP12 may be the same as those shown in FIG. Referring to FIG. 13, gNB-CU1 includes a network interface 1301, a processor 1302, and a memory 1303. Network interface 1301 is used to communicate with network nodes (eg, gNB-DU2 and control pool (CP) and user plane (UP) nodes in 5GC). The network interface 1301 may include a plurality of interfaces. The network interface 1301 may include, for example, an optical fiber interface for CU-DU communication and a network interface compliant with the IEEE 802.3 series.
[0078]
　Processor 1302 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communication. Processor 1302 may include a plurality of processors. For example, the processor 1302 is a modem processor (eg, Digital Signal Processor (DSP)) that performs digital baseband signal processing and a protocol stack processor (eg, Central Processing Unit (CPU) or Micro Processing Unit (eg, Central Processing Unit (CPU)) that performs control plane processing. MPU)) may be included.
[0079]
　The memory 1303 is composed of a combination of a volatile memory and a non-volatile memory. Volatile memory is, for example, Static Random Access Memory (SRAM) or Dynamic RAM (DRAM), or a combination thereof. The non-volatile memory can be a mask Read Only Memory (MROM), an Electrically Erasable Programmable ROM (EEPROM), a flash memory, or a hard disk drive, or any combination thereof. Memory 1303 may include storage located away from processor 1302. In this case, processor 1302 may access memory 1303 via network interface 1301 or an I / O interface (not shown).
[0080]
　The memory 1303 may store one or more software modules (computer programs) 1304 including instructions and data for performing processing by the gNB-CU1 described in the plurality of embodiments described above. In some implementations, processor 1302 may be configured to perform the processing of gNB-CU1 described in the embodiments described above by reading and executing the one or more software modules 1304 from memory 1303. Good.
[0081]
　FIG. 14 is a block diagram showing a configuration example of gNB-DU2 according to the above-described embodiment. Referring to FIG. 14, gNB-DU2 includes a Radio Frequency transceiver 1401, a network interface 1403, a processor 1404, and a memory 1405. RF transceiver 1401 performs analog RF signal processing to communicate with NG UEs. The RF transceiver 1401 may include a plurality of transceivers. The RF transceiver 1401 is coupled with the antenna array 1402 and the processor 1404. The RF transceiver 1401 receives the modulation symbol data from the processor 1404, generates a transmit RF signal, and supplies the transmit RF signal to the antenna array 1402. Further, the RF transceiver 1401 generates a baseband reception signal based on the reception RF signal received by the antenna array 1402, and supplies the baseband reception signal to the processor 1404. The RF transceiver 1401 may include an analog beamformer circuit for beamforming. The analog beamformer circuit includes, for example, a plurality of phase shifters and a plurality of power amplifiers.
[0082]
　The network interface 1403 is used to communicate with network nodes (eg, gNB-CU1, gNB-CU-CP11, gNB-CU-UP12). The network interface 1403 may include a plurality of interfaces. The network interface 1403 may include, for example, at least one of an optical fiber interface for CU-DU communication and an IEEE 802.3 series compliant network interface.
[0083]
　Processor 1404 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communication. Processor 1404 may include a plurality of processors. For example, processor 1404 may include a modem processor (eg, DSP) for digital baseband signal processing and a protocol stack processor (eg, CPU or MPU) for control plane processing. Processor 1404 may include a digital beamformer module for beamforming. The digital beamformer module may include a Multiple Input Multiple Output (MIMO) encoder and precoder.
[0084]
　The memory 1405 is composed of a combination of a volatile memory and a non-volatile memory. Volatile memory is, for example, SRAM or DRAM or a combination thereof. Non-volatile memory can be MROM, EEPROM, flash memory, or a hard disk drive, or any combination thereof. Memory 1405 may include storage located away from processor 1404. In this case, processor 1404 may access memory 1405 via network interface 1403 or an I / O interface (not shown).
[0085]
　The memory 1405 may store one or more software modules (computer programs) 1406 containing instructions and data for performing processing by the gNB-DU2 described in the plurality of embodiments described above. In some implementations, processor 1404 may be configured to perform the processing of gNB-DU2 described in the embodiments described above by reading and executing the one or more software modules 1406 from memory 1405. Good.
[0086]
　As described with reference to FIGS. 13 and 14, each of the processors included in the gNB-CU1 and gNB-DU2 according to the above-described embodiment is a group of instructions for causing the computer to perform the algorithm described with reference to the drawings. Execute one or more programs including. This program can be stored and supplied to a computer using various types of non-transitory computer readable media. Non-transitory computer-readable media include various types of tangible storage media. Examples of non-temporary computer-readable media include magnetic recording media (eg flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg magneto-optical disks), Compact Disc Read Only Memory (CD-ROM), CD- Includes R, CD-R / W, semiconductor memory (eg, mask ROM, Programmable ROM (PROM), Erasable PROM (EPROM), flash ROM, Random Access Memory (RAM)). The program may also be supplied to the computer by various types of transient computer readable media. Examples of temporary computer-readable media include electrical, optical, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.
[0087]
The
　above-described embodiment shows an example in which gNB-CU1 uses the UE list received from gNB-DU2 to determine UEs that require transmission of updated SI via individual signaling. It was. However, gNB-CU1 may use the UE list received from gNB-DU2 for other purposes.
[0088]
　The signaling between gNB-CU1 and gNB-DU2 described in the above embodiment may be performed between gNB-CU-CP11 and gNB-DU2.
[0089]
　Furthermore, the above-described embodiment is merely an example relating to the application of the technical idea obtained by the inventor of the present invention. That is, the technical idea is not limited to the above-described embodiment, and it goes without saying that various changes can be made.
[0090]
　For example, some or all of the above embodiments may also be described, but not limited to:
[0091]
(Supplementary Note 1)
　A distribution unit of a base station,
　and at least one memory,
　the at least one processor coupled to at least one memory,
comprising a
　at least one processor, at least one terminal list 　Multiple radio terminals configured to transmit to the central unit of the base station and the
　at least one terminal list is
not configured with a Common Search Space in each activation downlink Bandwidth Part (BWP);
　each activation. Multiple radio terminals for which at least a Search Space (SS) for receiving system information is not set in the downlink BWP; multiple radios
　that need to receive updated system information via individual signaling for each radio terminal. A distributed unit indicating at least one of a 　terminal; a plurality of wireless terminals in which
　each activated downlink BWP is a non-initial downlink BWP; and a plurality of wireless terminals
receiving on each downlink BWP .

[0092]
(Appendix 2) The
　at least one processor sends the at least one terminal list to the central unit in response to receiving a first control message including a system information update notification from the central unit.
The dispersion unit according to Appendix 1, which is configured .
[0093]
(Appendix 3) The distributed unit according to Appendix 2,
　wherein the first control message is a SYSTEM INFORMATION DELIVERY COMMAND message
.
[0094]
(Supplementary Note 4) Any of Supplementary note 1 to 3,
　wherein the at least one processor is configured to transmit the at least one terminal list to the central unit in response to a decision to update system information
. The distribution unit according to item 1.
[0095]
(Supplementary Note 5) Any of Supplementary note 1 to 4,
　wherein the at least one processor is configured to transmit the at least one terminal list to the central unit in response to receiving a request from the central unit.
The distribution unit according to item 1.
[0096]
(Supplementary note 6) The distributed unit according to any one of Supplementary note 1 to 5,
　wherein the at least one terminal list indicates a plurality of wireless terminals for which a common search space is not set in each activation downlink BWP
.
[0097]
(Appendix 7) The
　at least one terminal list indicates a plurality of wireless terminals in which at least a Search Space (SS) for receiving system information is not set in each activation downlink BWP, and the above-mentioned at least one terminal list indicates the plurality of wireless terminals of the
appendices 1 to 5. The distribution unit according to any one item.
[0098]
(Supplementary Note 8) The distributed unit according to any one of Supplementary note 1 to 5,
　wherein the at least one terminal list indicates a plurality of wireless terminals in which each activated downlink BWP is a non-initial downlink BWP
.
[0099]
(Supplementary note 9) The description in any one of Supplementary note 1 to 5,
　wherein the at least one terminal list includes a terminal list for each BWP for indicating a plurality of wireless terminals receiving on each downlink BWP
. Distributed unit.
[0100]
(Appendix 10)
　A central unit of a base station 　comprising at least one
　memory and
at least one processor coupled to the at least one memory
,
　wherein the at least one processor has at least one terminal list. It is configured to receive from the distribution unit of the base station,
　the at least one terminal list,
　a plurality of wireless terminals that are not configured to Common Search Space (CSS) in each of the activated downlink Bandwidth Part (BWP);
　each Multiple wireless terminals for which at least a Search Space (SS) for receiving system information is not set in the downlink BWP;
　it is necessary to receive updated system information via individual signaling for each wireless terminal. a plurality of wireless terminals;
　and; each activated downlink BWP plurality of wireless terminals is a non-initial downlink BWP
　plurality of wireless terminals receiving on each downlink BWP;
exhibits at least one of,
Central unit.
[0101]
(Supplementary Note 11) The
　at least one processor is configured to transmit a first control message including a system information update notification to the distributed unit, and
　the first control message includes the at least one terminal list. The central unit according to
Appendix 10, which causes the distributed unit to transmit to the central unit.
[0102]
(Supplementary note 12) The central unit according to Supplementary note 11,
　wherein the first control message is a SYSTEM INFORMATION DELIVERY COMMAND message
.
[0103]
(Supplementary Note 13) The central unit according to any one of Supplementary note 10 to 12
　, wherein the at least one processor is configured to transmit a request for the at least one terminal list to the distributed
unit.
[0104]
(Appendix 14) The
　at least one processor is configured to transmit updated system information to one or more wireless terminals via individual signaling for each wireless terminal after receiving the at least one terminal list. It is,
　the central unit according to any one of appendices 10-13.
[0105]
(Supplementary note 15) The
　above-mentioned at least one terminal list indicates a plurality of wireless terminals for which a Common Search Space (CSS) is not set in each activation downlink BWP, according
to any one of Supplementary note 10 to 14. Central unit.
[0106]
(Supplementary Note 16)
　said at least one terminal list shows a plurality of wireless terminals that are not configured at least Search Space for receiving system information (SS) in each of the activated downlink BWP,
the appended 10-14 The central unit according to any one item.
[0107]
(Supplementary note 17) The central unit according to any one of Supplementary note 10 to 14,
　wherein the at least one terminal list indicates a plurality of wireless terminals in which each activated downlink BWP is a non-initial downlink BWP
.
[0108]
(Supplementary note 18) The
　above-mentioned at least one terminal list is
described in any one of Appendix 10 to 14, including a terminal list for each BWP for indicating a plurality of wireless terminals receiving on each downlink BWP . Central unit.
[0109]
(Appendix 19)
　A method in a distributed unit of a
　base station,
　comprising transmitting at least one terminal list to the central unit of the base station, wherein the at least one terminal list is a
　respective activation downlink Bandwidth Part. Multiple wireless terminals that do not have a Common Search Space (CSS) set in (BWP); multiple wireless terminals that do not have
　a Search Space (SS) set to receive at least system information in each activation downlink BWP. ;
　multiple wireless terminals that need to receive updated system information through a separate signaling for each wireless terminal;
　a plurality of radio terminals each activated downlink BWP is a non-initial downlink BWP; and
　each down Link A method
of indicating at least one of multiple wireless terminals receiving on a BWP
.
[0110]
(Appendix 20)
　A method in the central unit of a
　base station,
　comprising receiving at least one terminal list from the distributed unit of the base station, wherein the at least one terminal list is a
　respective activation downlink Bandwidth Part. Multiple wireless terminals that do not have a Common Search Space set in (BWP); multiple wireless terminals that do not have
　a Search Space (SS) set to receive at least system information in each activation downlink BWP;
　updated Multiple wireless terminals that need to receive system information via individual signaling for
　each wireless terminal; multiple wireless terminals for which each activated downlink BWP is a non-initial downlink BWP; and on
　each downlink BWP A method
of indicating at least one of a plurality of wireless terminals receiving in
.
[0111]
(Appendix 21)
　A program for causing a computer to perform a method in a distributed unit of a base station,
　wherein the method comprises transmitting at least one terminal list to the central unit of the base station
　. The terminal list is a
　plurality of wireless terminals for which a common search space is not set in each activation downlink Bandwidth Part (BWP);
　Search Space (SS) for receiving at least system information in each activation downlink BWP. Multiple wireless terminals that are not set; Multiple wireless terminals
　that need to receive updated system information via individual signaling for
　each wireless terminal; Each activation downlink BWP is a non-initial downlink BWP A program indicating at least one of a plurality of wireless terminals; and a plurality of wireless terminals
　receiving on each downlink BWP .

[0112]
(Appendix 22)
　A program for causing a computer to perform a method in a central unit of a base station,
　wherein the method comprises receiving at least one terminal list from the distributed unit of the base station,
　said at least one. The terminal list is a
　plurality of wireless terminals for which a common search space is not set in each activation downlink Bandwidth Part (BWP);
　Search Space (SS) for receiving at least system information in each activation downlink BWP. Multiple wireless terminals that are not set; Multiple wireless terminals
　that need to receive updated system information via individual signaling for
　each wireless terminal; Each activation downlink BWP is a non-initial downlink BWP A program indicating at least one of a plurality of wireless terminals; and a plurality of wireless terminals
　receiving on each downlink BWP .

[0113]
(Supplementary Note 23)
　A distribution unit of a base station,
　and at least one memory,
　the at least one processor coupled to at least one memory,
comprising a
　at least one processor is activated down of the wireless terminal A
distributed unit configured to send a message containing an information element indicating a change in the link Bandwidth Part (BWP) to the central unit of the base station .
[0114]
(Supplementary Note 24) The distribution according to Supplementary note 23,
　wherein the at least one processor is configured to transmit the message to the central unit of the base station in response to a change in the activation downlink BWP of the radio terminal.
unit.
[0115]
(Supplementary note 25) The distributed unit according to Supplementary note 23 or 24,
　wherein the information element indicates whether or not the activated downlink BWP of the wireless terminal has been changed from the initial downlink BWP to the non-initial downlink BWP
.
[0116]
(Supplementary note 26) The distributed unit according to Supplementary note 23 or 24,
　wherein the information element indicates that the activation downlink BWP of the wireless terminal does not have a Common Search Space
.
[0117]
(Supplementary note 27) The distribution unit according to Supplementary note 23 or 24,
　wherein the information element indicates an identifier of the activated downlink BW after the change of the wireless terminal
.
[0118]
(Supplementary Note 28)
　A central unit of the base station,
　and at least one memory,
　the at least one processor coupled to at least one memory,
comprising a
　at least one processor is activated down of the wireless terminal A
central unit configured to receive a message from the base station's distributed unit that includes an information element indicating a change in the link BWP .
[0119]
(Supplementary note 29) The central unit according to Supplementary note 28,
　wherein the information element indicates whether or not the activated downlink BWP of the wireless terminal has been changed from the initial downlink BWP to the non-initial downlink BWP
.
[0120]
(Supplementary Note 30) The central unit according to Supplementary note 28,
　wherein the information element indicates that the activation downlink BWP of the wireless terminal does not have a Common Search Space
.
[0121]
(Supplementary Note 31) The central unit according to Supplementary note 28,
　wherein the information element indicates an identifier of the activated downlink BW after the change of the wireless terminal
.
[0122]
(Appendix 32) The
　at least one processor is configured to transmit the updated system information to the wireless terminal via individual signaling for each wireless terminal after receiving the information element
　. The central unit according to any one item.
[0123]
(Appendix 33)
　A method in a distributed unit of a
　base station, comprising transmitting a message including an information element indicating a change in the activation downlink Bandwidth Part (BWP) of the wireless terminal to the central unit of the base station. ,
How.
[0124]
(Appendix 34)
　A method in a central unit of a
　base station, comprising receiving a message from the distributed unit of the base station that includes an information element indicating a change in activation downlink BWP of a wireless terminal
.
[0125]
　This application claims priority on the basis of Japanese application Japanese Patent Application No. 2018-150709 filed on August 9, 2018, and incorporates all of its disclosures herein.
Code description
[0126]
1 gNB-CU
2 gNB-DU
3 UE
11 gNB-CU-CP
12 gNB-CU-UP
1302 Processor
1303 Memory
1304 Modules
1404 Processor
1405 Memory
1406 Modules
The scope of the claims
[Claim 1]
　A distribution unit of the base station,
　and at least one memory,
　the at least one processor coupled to at least one memory,
comprising a
　at least one processor, at least one terminal list of the base station is configured to transmit to the central unit,
　said at least one terminal list,
　a plurality of wireless terminals that are not configured to Common Search Space in each of the activated downlink Bandwidth Part (BWP);
　in each of the activated downlink BWP Multiple wireless terminals for which at least a Search Space (SS) for receiving system information is not set; multiple wireless terminals
　that need to receive updated system information via individual signaling for
　each wireless terminal; A distributed unit indicating at least one of a plurality of radio terminals whose activated downlink BWP is a non-initial downlink BWP; and a plurality of radio terminals
　receiving on each downlink BWP .

[Claim 2]
　The at least one processor is configured to transmit the at least one terminal list to the central unit in response to receiving a first control message including a system information update notification from the central unit. ,
The distribution unit according to claim 1.
[Claim 3]

The distributed unit according to claim 2, 　wherein the first control message is a SYSTEM INFORMATION DELIVERY COMMAND message .
[Claim 4]
　According to any one of
claims 1 to 3, the at least one processor is configured to transmit the at least one terminal list to the central unit in response to a decision to update system information. Described distribution unit.
[Claim 5]

Any one of claims 1 to 4, 　wherein the at least one processor is configured to transmit the at least one list of terminals to the central unit in response to receiving a request from the central unit. Dispersion unit described in.
[Claim 6]

The distributed unit according to any one of claims 1 to 5, 　wherein the at least one terminal list indicates a plurality of wireless terminals for which a common search space is not set in each activated downlink BWP .
[Claim 7]
　The at least one terminal list indicates a plurality of wireless terminals for which at least a Search Space (SS) for receiving system information is not set in each activated downlink BWP,
any one of claims 1 to 5. Dispersion unit as described in the section.
[Claim 8]

The distributed unit according to any one of claims 1 to 5, 　wherein the at least one terminal list indicates a plurality of wireless terminals in which each activated downlink BWP is a non-initial downlink BWP .
[Claim 9]

The distributed unit according to any one of claims 1 to 5, 　wherein the at least one terminal list includes a terminal list for each BWP for indicating a plurality of wireless terminals receiving on each downlink BWP .
[Claim 10]
　A central unit of the base station,
　and at least one memory,
　the at least one processor coupled to at least one memory,
comprising a
　at least one processor, at least one terminal list of the base station 　Multiple wireless terminals configured to receive from a distributed unit,
　said at least one terminal list is
not configured with a Common Search Space (CSS) in each activation downlink Bandwidth Part (BWP);
　each activation down Multiple wireless terminals for which at least Search Space (SS) for receiving system information is not set in the link BWP; Multiple wireless terminals
　that need to receive updated system information via individual signaling for each wireless terminal. A central unit indicating at least one of a 　plurality of radio terminals for which
　each activated downlink BWP is a non-initial downlink BWP; and a plurality of radio terminals
receiving on each downlink BWP .

[Claim 11]
　The at least one processor is configured to send a first control message, including a system information update notification, to the distributed unit, the first control message sending the
　at least one terminal list to the central unit.
The central unit according to claim 10, which causes the distributed unit to do so .
[Claim 12]

The central unit according to claim 11, 　wherein the first control message is a SYSTEM INFORMATION DELIVERY COMMAND message .
[Claim 13]

The central unit according to any one of claims 10 to 12 　, wherein the at least one processor is configured to transmit a request for the at least one terminal list to the distributed unit.
[Claim 14]
　Wherein the at least one processor, after the reception of the at least one terminal list, is configured to transmit updated system information to one or more wireless terminals via a separate signaling for each wireless terminal,
　claim The central unit according to any one of 10 to 13.
[Claim 15]

The central unit according to any one of claims 10 to 14, 　wherein the at least one terminal list indicates a plurality of wireless terminals for which a Common Search Space (CSS) is not set in each activation downlink BWP .
[Claim 16]
　The at least one terminal list indicates a plurality of wireless terminals for which at least a Search Space (SS) for receiving system information is not set in each activated downlink BWP,
any one of claims 10 to 14. Central unit as described in section.
[Claim 17]

The central unit according to any one of claims 10 to 14, 　wherein the at least one terminal list indicates a plurality of wireless terminals in which each activated downlink BWP is a non-initial downlink BWP .
[Claim 18]

The central unit according to any one of claims 10 to 14, 　wherein the at least one terminal list includes a terminal list for each BWP for indicating a plurality of wireless terminals receiving on each downlink BWP .
[Claim 19]
　A method in a distributed unit of a
　base station,
　comprising transmitting at least one terminal list to the central unit of the base station, said at least one terminal list in
　each activation downlink Bandwidth Part (BWP). Multiple wireless terminals not configured with Common Search Space (CSS); Multiple wireless terminals not configured with
　Search Space (SS) to receive at least system information in each activation downlink BWP;
　updated Multiple wireless terminals that need to receive system information via individual signaling for
　each wireless terminal; multiple wireless terminals where each activated downlink BWP is a non-initial downlink BWP; and on
　each downlink BWP A method
of indicating at least one of a plurality of receiving wireless terminals;
[Claim 20]
　A method in the central unit of a
　base station,
　comprising receiving at least one terminal list from the distributed unit of the base station, said at least one terminal list in
　each activation downlink Bandwidth Part (BWP). Multiple wireless terminals not set with Common Search Space; Multiple wireless terminals without set
　Search Space (SS) to receive at least system information in each activation downlink BWP;
　Updated system information Multiple radio terminals that need to be received via individual signaling for
　each radio terminal; multiple radio terminals where each activated downlink BWP is a non-initial downlink BWP; and
　received on each downlink BWP A method
of indicating at least one of a plurality of wireless terminals
.
[Claim 21]
　A non-temporary computer-readable medium containing a program for causing a computer to perform a method in a distributed unit of a base station,
　wherein the method transmits at least one terminal list to the central unit of the base station. The
　at least one terminal list includes a
　plurality of wireless terminals for which a common search space is not set in each activation downlink Bandwidth Part (BWP);
　for receiving at least system information in each activation downlink BWP. Multiple wireless terminals for which Search Space (SS) is not set; Multiple wireless terminals
　that need to receive updated system information via individual signaling for
　each wireless terminal; Each activation downlink BWP is non- A non-transitory computer-readable medium indicating at least one of a plurality of wireless terminals that are initial downlink BWPs; and a plurality of wireless terminals
　that are receiving on each downlink BWP .

[Claim 22]
　A non-temporary computer-readable medium containing a program for causing a computer to perform a method in a central unit of a base station,
　wherein the method receives at least one terminal list from the distributed unit of the base station. The
　at least one terminal list includes a
　plurality of wireless terminals for which a common search space is not set in each activation downlink Bandwidth Part (BWP);
　for receiving at least system information in each activation downlink BWP. Multiple wireless terminals for which Search Space (SS) is not set; Multiple wireless terminals
　that need to receive updated system information via individual signaling for
　each wireless terminal; Each activation downlink BWP is non- A non-transitory computer-readable medium indicating at least one of a plurality of wireless terminals that are initial downlink BWPs; and a plurality of wireless terminals
　that are receiving on each downlink BWP .

[Claim 23]
　A base station distributed unit 　comprising at least one
　memory and
at least one processor coupled to the at least one memory
,
　wherein the at least one processor is a wireless terminal activation downlink Bandwidth Part ( A
distributed unit configured to send a message containing an information element indicating a change in BWP) to the central unit of the base station .
[Claim 24]

23. The distributed unit of claim 23, 　wherein the at least one processor is configured to transmit the message to the central unit of the base station in response to a change in the activation downlink BWP of the radio terminal .
[Claim 25]

The distribution unit according to claim 23 or 24, 　wherein the information element indicates whether or not the activated downlink BWP of the wireless terminal has been changed from the initial downlink BWP to the non-initial downlink BWP .
[Claim 26]

The distribution unit according to claim 23 or 24, 　wherein the information element indicates that the activation downlink BWP of the wireless terminal does not have a Common Search Space .
[Claim 27]

The distribution unit according to claim 23 or 24, 　wherein the information element indicates an identifier of the activated downlink BW after the modification of the wireless terminal .
[Claim 28]
　A central unit of a base station 　comprising at least one
　memory and
at least one processor coupled to the at least one memory
,
　wherein the at least one processor modifies the activation downlink BWP of the wireless terminal. A
central unit configured to receive a message from a distributed unit of the base station that includes an information element indicating .
[Claim 29]

28. The central unit of claim 28, 　wherein the information element indicates whether the activated downlink BWP of the wireless terminal has been changed from an initial downlink BWP to a non-initial downlink BWP .
[Claim 30]

28. The central unit of claim 28, 　wherein the information element indicates that the activation downlink BWP of the wireless terminal does not have a Common Search Space .
[Claim 31]

28. The central unit of claim 28, 　wherein the information element indicates an identifier for the modified activated downlink BW of the wireless terminal .
[Claim 32]

　Any one of claims 28 to 31, 　wherein the at least one processor transmits the updated system information to the wireless terminal via individual signaling for each wireless terminal after receiving the information element. Central unit as described in section.
[Claim 33]
　A method in a distributed unit of a
　base station, comprising transmitting a message comprising an information element indicating a change in the activation downlink Bandwidth Part (BWP) of the radio terminal to the central unit of the base station
.
[Claim 34]
　A method in a central unit of a
　base station, comprising receiving a message from the distributed unit of the base station that includes an information element indicating a change in the activation downlink BWP of the wireless terminal