Title of invention: Wireless communication device, wireless communication terminal, and wireless communication method
Technical field
[0001]
　The present technology relates to a wireless communication device, a wireless communication terminal, and a wireless communication method, and particularly to a wireless communication device, a wireless communication terminal, and a wireless communication device that can avoid packet collision in full-duplex communication. Regarding communication method.
Background technology
[0002]
　Currently, full-duplex communication capable of performing transmission and reception at the same time is under consideration as a technique for achieving higher efficiency in wireless communication. A wireless communication device and a wireless communication terminal compatible with full-duplex communication can perform packet transmission and reception at the same time, and therefore it is expected that frequency utilization efficiency will be significantly improved.
[0003]
　For example, Patent Document 1 describes a technique that enables communication with another extended wireless station while the extended wireless station is transmitting or receiving in order to effectively utilize the simultaneous transmission/reception function of the extended wireless station. Has been done.
Prior art documents
Patent literature
[0004]
Patent Document 1: Japanese Unexamined Patent Publication No. 2017-028341
Summary of the invention
Problems to be Solved by the Invention
[0005]
　In a full-duplex communication system including a wireless communication device and a wireless communication terminal that support full-duplex communication, the wireless communication device and the wireless communication terminal can perform transmission and reception at the same time. Uplink communication from a first wireless communication terminal as a slave to a wireless communication apparatus as a base station (master) and downlink communication from a base station to a second wireless communication terminal as a second slave. It is assumed that they will be performed at the same time.
[0006]
　However, depending on the arrangement of the base station, the first slave, and the second slave, for example, for downlink communication from the base station to the second slave, from the first slave to the base station Of the uplink communication becomes interference and the packet transmitted by the base station and the packet transmitted by the first slave unit collide with each other, and the second slave unit performs downlink communication from the base station to the second slave unit. It may fail to receive the transmitted packets.
[0007]
　In addition, when the base station performs downlink communication to the second handset and receives a packet from the first handset, the third wireless communication terminal as the third handset operates as a base station. When the uplink communication to the mobile station is started, the packet transmitted by the first slave unit and the packet transmitted by the third slave unit collide with each other, and the base station may fail to receive the packet.
[0008]
　The present technology has been made in view of such a situation, and makes it possible to avoid packet collision in full-duplex communication.
Means for solving the problem
[0009]
　A wireless communication device of the present technology is transmitted from the wireless communication terminal of a wireless communication system including a wireless communication device that functions as a base station and one or more wireless communication terminals that communicate with the wireless communication device as slaves. A packet that is transmitted from the wireless communication device during a downlink transmission period during which the packet is received, and a communication unit that transmits a packet including the availability information. It is a communication device.
[0010]
　A first wireless communication method according to an embodiment of the present technology is a wireless communication terminal of a wireless communication system that includes a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate with the wireless communication device as a child device. And setting propriety information indicating whether the packet transmitted from the wireless communication device can be received during a downlink transmission period in which the packet is transmitted from the wireless communication device, and transmitting a packet including the propriety information. It is a wireless communication method.
[0011]
　In a wireless communication device and a first wireless communication method of the present technology, wireless communication including a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate with the wireless communication device as a slave unit. In the system, permission/inhibition information indicating whether or not the packet transmitted from the wireless communication terminal can be received during the downlink transmission period in which the packet is transmitted from the wireless communication device is set, and the packet including the permission/inhibition information is transmitted. To be done.
[0012]
　A wireless communication terminal of the present technology is transmitted from the wireless communication terminal of a wireless communication system including a wireless communication apparatus that functions as a base station and one or more wireless communication terminals that communicate with the wireless communication apparatus as slaves. A packet to be transmitted to the wireless communication device according to the availability information included in the packet including availability information indicating whether the packet can be received during a downlink transmission period in which the packet is transmitted from the wireless communication device. The wireless communication terminal includes a control unit that controls transmission.
[0013]
　A second wireless communication method of the present technology is the wireless communication terminal of a wireless communication system including a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate with the wireless communication device as a child device. The packet transmitted from the wireless communication device to the wireless communication device in accordance with the availability information included in the packet including the availability information indicating whether the packet can be received during the downlink transmission period in which the packet is transmitted from the wireless communication device. Wireless communication method including controlling the transmission of the packet.
[0014]
　In a wireless communication terminal and a second wireless communication method according to an embodiment of the present technology, wireless communication including a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate with the wireless communication device as a child device. According to the availability information included in the packet of the system, which includes availability information indicating whether the packet transmitted from the wireless communication terminal can be received during the downlink transmission period in which the packet is transmitted from the wireless communication device. Thus, the transmission of packets to the wireless communication device is controlled.
Effect of the invention
[0015]
　According to the present technology, it is possible to avoid packet collision in full-duplex communication.
[0016]
　Note that the effects described here are not necessarily limited, and may be any effects described in the present disclosure.
Brief description of the drawings
[0017]
FIG. 1 is a diagram showing a configuration example of an embodiment of a wireless communication system to which the present technology is applied.
FIG. 2 is a block diagram showing a configuration example of a communication device 20.
FIG. 3 is a block diagram showing a configuration example of a communication device 30.
FIG. 4 is a diagram showing a first embodiment of a format of a packet transmitted in downlink communication from AP1 (communication device 20) to STA#i (communication device 30 i ).
FIG. 5 is a sequence diagram illustrating an example of an operation performed in AP1 and STA1 to STA4.
FIG. 6 is a flowchart illustrating an example of processing performed by AP1.
FIG. 7 is a flowchart illustrating an example of processing performed by STA#i.
FIG. 8 is a diagram showing a second embodiment of a format of a DL packet transmitted in downlink communication from AP1 (communication device 20) to STA#i (communication device 30 i ).
9 is a flowchart illustrating an example of processing performed by AP1 when the DL packet of FIG. 8 is transmitted.
FIG. 10 is a flowchart illustrating an example of processing performed by STA#i when the DL packet of FIG. 8 is transmitted.
FIG. 11 is a block diagram showing a configuration example of an embodiment of a computer to which the present technology is applied.
MODE FOR CARRYING OUT THE INVENTION
[0018]
　
[0019]
　FIG. 1 is a diagram illustrating a configuration example of an embodiment of a wireless communication system to which the present technology is applied.
[0020]
　The wireless communication system 10 shown in FIG. 1 constitutes a wireless LAN (Local Area Network) standardized by IEEE (Institute of Electrical and Electronic Engineers) 802.11, for example, and includes a communication device 20 and a communication device 30 1. , Communication device 30 2 , communication device 30 3 , and communication device 30 4 .
[0021]
　The communication device 20 is a wireless communication device that functions as a base station (master device) in a wireless LAN, and is a full-duplex communication compatible wireless communication device that can simultaneously perform transmission and reception.
[0022]
　Communication device 30 1 to 30 4 , for example, such as a smart phone, in a wireless LAN, a wireless communication terminal which functions as a slave unit.
[0023]
　The communication device 20 and the communication device 30 i perform wireless communication according to, for example, the IEEE 802.11 standard.
[0024]
　Here, the communication device 20 is also referred to as an AP (Access Point) 1, and the communication device 30 1 , the communication device 30 2 , the communication device 30 3 , and the communication device 30 4 are referred to as STA (Station) 1, STA 2, STA 3 , respectively. Also described as STA4. Also, communication in which packets are transmitted from AP1 to STA#i (here, i=1,2,3,4) is also called downlink communication, and conversely, communication in which packets are transmitted from STA#i to AP1 is Also called upstream communication.
[0025]
　In FIG. 1, the communication device 30 1 (STA1) is performing uplink communication (UL:UpLink) with the communication device 20 (AP1), and the communication device 20 (AP1) is downlink communication with the communication device 30 2 (STA2). (DL:DownLink)
[0026]
　Hereinafter, when it is not necessary to distinguish the communication devices 30 1 to 30 4 from each other as appropriate, they are simply referred to as the communication device 30.
[0027]
　The configuration of the wireless communication system 10 illustrated in FIG. 1 is an example, and the configuration of the wireless communication system 10 is not limited to this example. Further, for example, the numbers of the communication devices 20 and the communication devices 30 are arbitrary and are not limited to the embodiment of FIG.
[0028]
　
[0029]
　FIG. 2 is a block diagram showing a configuration example of the communication device 20.
[0030]
　As shown in FIG. 2, the communication device 20, data processing unit 51, the control unit 52, a communication unit 53, an antenna 66 1 through 66 N , and, and a power supply unit 71. Communication unit 53, modem unit 61, the signal processing unit 62, the channel estimation unit 63, the radio interface unit 64 1 through 64 N , and the amplifier unit 65 1 to no 65 N having.
[0031]
　When transmitting data input from the protocol upper layer, that is, when a packet (frame) is transmitted, the data processing unit 51 generates a packet for wireless transmission from the data input from the protocol upper layer. , Data processing such as addition of a header for performing media access control (MAC) and addition of an error detection code are performed. The data processing unit 51 supplies the packet obtained by the data processing to the modulation/demodulation unit 61.
[0032]
　When the data processing unit 51 receives data from the modulation/demodulation unit 61, that is, when a packet is received, the data processing unit 51 analyzes the MAC header of the packet supplied from the modulation/demodulation unit 61, detects a packet error, performs reorder processing, etc. Data processing of. The data processing unit 51 supplies the data obtained by the data processing to the protocol upper layer.
[0033]
　The control unit 52 includes the respective units (the data processing unit 51, the control unit 52, and the communication unit 53 (the modulation/demodulation unit 61, the signal processing unit 62, the channel estimation unit 63, the wireless interface units 64 1 to 64 N , and the amplifier unit 65. 1 to 65 N perform)) exchange information between. Further, the control unit 52 controls each unit, for example, parameter setting in the modulation/demodulation unit 61 and the signal processing unit 62, packet scheduling in the data processing unit 51, wireless interface units 64 1 to 64 N and amplifier units 65 1 to 65 N. Parameter setting and transmission power control.
[0034]
　When downlink communication is performed, the control unit 52 determines whether or not the uplink communication packet of the communication device 30 can be received according to the uplink communication status of the communication device 30, and the communication device 30 according to the determination result. The permission/inhibition information indicating whether or not the packet transmitted from the communication device 20 can be received during the downlink transmission period in which the packet is transmitted from the communication device 20 is set. Further, the control unit 52 controls each unit so that the availability information is included in the downlink communication packet.
[0035]
　The communication unit 53 performs processing necessary for transmitting/receiving packets by wireless communication, and transmits/receives packets via the antenna 66 i .
[0036]
　The antenna 66 i transmits the packet supplied from the communication unit 53 as a wireless signal. Further, the antenna 66 i receives the packet radio signal and supplies the packet radio signal to the communication unit 53.
[0037]
　When the packet is transmitted, the modulation/demodulation unit 61 encodes the packet supplied from the data processing unit 51 based on the coding and modulation scheme parameterized by the control unit 52, performs interleaving, and , Conversion processing such as modulation is performed to generate a data symbol stream. The modulator/demodulator 61 supplies the generated data symbol stream to the signal processor 62.
[0038]
　On the other hand, when the packet is received, the modulation/demodulation unit 61 performs the opposite (reverse) process to the data symbol stream supplied from the signal processing unit 62, which is the reverse of the process for transmitting the packet. That is, the modulation/demodulation unit 61 performs reverse processing such as demodulation, deinterleaving, and decoding on the data symbol stream supplied from the signal processing unit 62, and obtains a packet obtained by the reverse processing. The data is supplied to the data processing unit 51 and the control unit 52.
[0039]
　When a packet is transmitted, the signal processing unit 62 performs signal processing including spatial processing such as MIMO (Multiple-Input and Multiple-Output) on the data symbol stream from the modulation/demodulation unit 61, if necessary. Generate one or more transmitted symbol streams. The signal processing unit 62 supplies the generated transmission symbol streams to the wireless interface unit 64 i .
[0040]
　On the other hand, when the packet is received, the signal processing unit 62 performs signal processing on the received symbol stream supplied from the wireless interface unit 64 i and, if necessary, performs spatial processing on the received symbol stream. Then, the resulting data symbol stream is supplied to the modem unit 61.
[0041]
　The channel estimation unit 63 calculates the complex channel gain of the propagation path based on the preamble portion and the training signal portion of the received symbol stream supplied from the wireless interface unit 64 i . The channel estimation unit 63 supplies the calculated complex channel gain to the modulation/demodulation unit 61 and the signal processing unit 62 via the control unit 52. The modulation/demodulation unit 61 uses the complex channel gain supplied from the channel estimation unit 63 for demodulation processing. The signal processing unit 62 uses the complex channel gain supplied from the channel estimation unit 63 for spatial processing.
[0042]
　When a packet is transmitted, the wireless interface unit 64 i performs DA (Digital to Analog) conversion of a transmission symbol stream, which is an input from the signal processing unit 62, into an analog signal, performs filtering, and up-converts to a carrier frequency. Etc. are processed. The wireless interface unit 64 i supplies a transmission signal obtained by processing such as DA conversion, filtering, and up-conversion to carrier frequency to the amplifier unit 65 i .
[0043]
　On the other hand, when the packet is received , the wireless interface unit 64 i performs the process opposite to the process when the packet is transmitted on the input (received signal) from the amplifier unit 65 i , and vice versa. The signal (received symbol stream) obtained by the processing is supplied to the signal processing unit 62 and the channel estimation unit 63.
[0044]
　When the packet is transmitted, the amplifier unit 65 i amplifies the transmission signal from the wireless interface unit 64 i to a predetermined power, and the communication device 20 transmits the amplified transmission signal as a wireless signal from the antenna 66 i. Yes (release in the air).
[0045]
　When the packet is received , the amplifier unit 65 i amplifies the radio signal received by the antenna 66 i to a predetermined power and supplies it to the radio interface unit 64 i as a received signal .
[0046]
　Regarding the amplifier unit 65 i , at least one of the function at the time of transmission and the function at the time of reception can be included in the wireless interface unit 64 i . When both the function at the time of transmission and the function at the time of reception are included in the wireless interface unit 64 i , the communication unit 53 is configured without the amplifier unit 65 i .
[0047]
　The power supply unit 71 is configured by a battery power supply or a fixed power supply, and supplies power to each unit of the communication device 20.
[0048]
　Here, the numbers of the wireless interface section 64 i , the amplifier section 65 i , and the antenna 66 i are arbitrary, and each may be a single number or three or more.
[0049]
　Also, the wireless interface unit 64 i , the amplifier unit 65 i , and the antenna 66 i may be one component (these may be configured as one processing unit).
[0050]
　FIG. 3 is a block diagram showing a configuration example of the communication device 30.
[0051]
　As shown in FIG. 3, the communication device 30 includes a data processing unit 151, a control unit 152, a communication unit 153, antennas 166 1 to 166 N, and a power supply unit 171. Communication unit 153, the modem unit 161, the signal processing section 162, channel estimation section 163, the wireless interface unit 164 1 to no 164 N , and the amplifier unit 165 1 to 165 N has a.
[0052]
　Here, the data processing unit 151, the communication unit 153 (the modulation/demodulation unit 161, the signal processing unit 162, the channel estimation unit 163, the wireless interface units 164 1 to 164 N , and the amplifier units 165 1 to 165 N ), the antennas 166 1 to 166. 166 N and the power supply unit 171 include a data processing unit 51, a communication unit 53 (a modulation/demodulation unit 61, a signal processing unit 62, a channel estimation unit 63, radio interface units 64 1 to 64 N , and an amplifier shown in FIG. The parts 65 1 to 65 N ), the antennas 66 1 to 66 N , and the power supply part 71 have the same configurations, respectively, and thus description thereof will be omitted.
[0053]
　Control unit 152, in the same manner as the control unit 52 of FIG. 2, each unit (data processing unit 151, and a communication unit 153 (the modem unit 161, the signal processing section 162, channel estimation section 163, the wireless interface unit 164 1 to no 164 N , And between the amplifier units 165 1 to 165 N )). The control unit 152, in the same manner as the control unit 52 of FIG. 2, the control of each part, for example, the parameter setting modem unit 161 and the signal processing unit 162, packet scheduling in the data processing unit 151, the wireless interface unit 164 1 to no 164 N and amplifier units 165 1 to 165 N are used to set parameters and control transmission power.
[0054]
　Further, the control unit 152 determines whether or not the packet can be transmitted to the communication device 20 based on the permission/inhibition information included in the packet for downlink communication, that is, the packet from the communication device 20. Accordingly, transmission of the packet to the communication device 20 is controlled. That is, when the availability information indicates that the packet can be received, the control unit 152 starts preparation for packet transmission and transmits the packet, and the availability information indicates that the packet is When the reception is disabled to the effect that reception is not possible, each unit is controlled so as to wait for packet transmission.
[0055]
　

[0056]
　FIG. 4 is a diagram showing a first embodiment of a format of a packet transmitted in downlink communication from AP1 (communication device 20) to STA#i (communication device 30 i ).
[0057]
　Here, the packet transmitted in the downlink communication from AP1 to STA#i is also referred to as a DL packet. In the DL packet according to the first embodiment, the header portion includes one piece of permission/prohibition information.
[0058]
　The DL packet shown in FIG. 4 is, for example, a packet standardized in IEEE802.11ax, and includes a PHY (Physical) header (Phy Header) as a header portion of the DL packet and a Data portion as a data portion of the DL packet. (MAC) and are arranged in that order. In the header part, L-STF, L-LTF, L-SIG, RL-SIG, HE-SIG-A, HE-STF, and HE-LTF are arranged in that order.
[0059]
　In AP1, for example, the header portion of a DL packet can include availability information indicating availability of packet reception by AP1. Regarding the availability information, a new field can be extended in HE-SIG-A of the header part, and the availability information can be included in the extended new field. In addition, the availability information can be included in the Reserved part of HE-SIG-A in the header part.
[0060]
　The permission/prohibition information can be included in any position other than HE-SIG-A in the header part. Further, the permission/prohibition information can be included in the new field by expanding a field as a new header section between the header section and the data section.
[0061]
　In addition, the availability information can be included in a field for including other existing information of the DL packet. Furthermore, the permission/prohibition information can be included in the HE-SIG-A at an arbitrary position such as in the middle, at the beginning, or at the end.
[0062]
　FIG. 5 is a sequence diagram illustrating an example of operations performed in AP1 and STA1 to STA4.
[0063]
　AP1 and STA#i, at the time of connection start, for example, the information of whether the operation according to the availability information can be implemented, for example, in the packet to be exchanged at the time of connection start, for example, including in the capability field, Send and receive. As a result, the AP1 and the STA#i mutually determine (understand) whether or not the operation according to the availability information can be performed. In addition, the STA#i transmits/receives (exchanges) packets between the STA#i and stores the reception power of the signal transmitted from another STA#i.
[0064]
　In FIG. 5, the horizontal axis represents time. Further, in FIG. 5, a solid line represents a packet transmission operation, and a dotted line represents another operation.
[0065]
　In FIG. 5, AP1 is performing downlink communication for transmitting a DL packet addressed to STA2 (TxDL).
[0066]
　The DL packet transmitted by the downlink communication from AP1 to STA2 includes the availability information and the information of STA2 which is the destination. The packet addressed to STA2 is received by STA2 (RxDL) and also received by STA1, STA3, and STA4 other than STA2.
[0067]
　Here, in uplink communication from STA#i to AP1, the packet transmitted by STA#i is also referred to as a UL packet.
[0068]
　Now, for example, when STA1 and STA3 send UL packets to AP1 in uplink communication, the amount of interference to STA2 is smaller than the first threshold, and STA2 when STA4 sends UL packets to AP1 in uplink communication. It is assumed that the amount of interference with is larger than the first threshold. Here, the first threshold is, for example, a fixed value held by STA#i, a threshold notified from AP1, or the like.
[0069]
　In STA#i, the amount of interference caused by transmitting a UL packet is estimated from the received power stored at the start of connection.
[0070]
　Each of STA1, STA3, and STA4 receives a DL packet addressed to STA2 from AP1, and detects from the destinations included in the DL packet that the destination of the DL packet from AP1 is STA2.
[0071]
　When the STA4 transmits the UL packet to the AP1, the amount of interference with the STA2, which is the destination of the downlink communication of the AP1, is larger than the first threshold. Therefore, the STA4 waits for the UL packet to be transmitted to the AP1. (Busy).
[0072]
　On the other hand, STA1 and STA3 are included in the DL packet addressed to STA2 because the amount of interference with STA2, which is the destination of the downlink communication of AP1 when transmitting the UL packet to AP1, is smaller than the first threshold value. If the information indicates that the UL packet can be received (the UL packet can be received), the preparation for transmitting the UL packet to the AP1, that is, the acquisition of the transmission right is started. In the present embodiment, for acquisition of the transmission right, for example, a random number of time slots (times) are set, and backoff is performed to wait for the time slots.
[0073]
　In FIG. 5, STA1 shows waiting time for one slot, and STA3 shows waiting time for two slots. Therefore, STA1 ends the backoff before STA3 and acquires the transmission right before STA3. After acquiring the transmission right, STA1 starts transmitting a UL packet to AP1 (TxUL).
[0074]
　STA3 tries to start transmitting UL packets to AP1 when backoff ends, but detects that STA1 is transmitting UL packets to AP1, that is, exceeds the second threshold value ( Detects that a signal of (greater than) (reception) power is being transmitted, and in response to that detection, waits for UL packet transmission to avoid collision with UL packet of STA1 (Busy) .. This avoids a collision between the UL packet transmitted by STA1 and the UL packet transmitted by STA3. Here, the second threshold is, for example, a threshold different from the first threshold, and is a fixed value held by STA#i, a threshold notified from AP1, or the like.
[0075]
　FIG. 6 is a flowchart illustrating an example of processing performed by AP1.
[0076]
　In step S11, the AP1 determines whether the UL packet for uplink communication can be received, based on whether or not the UL packet for uplink communication is received from the STA#i (status of uplink communication).
[0077]
　In step S11, when the AP1 determines that the UL packet for upstream communication can be received, that is, when the UL packet is not received from any STA#i, the process proceeds to step S12.
[0078]
　In step S12, AP1 sets the permission/prohibition information so as to indicate that the reception is possible, and the process proceeds to step S13.
[0079]
　On the other hand, in step S11, when the AP1 determines that the UL packet for uplink communication cannot be received, that is, when the UL packet is received from any STA#i, the process proceeds to step S15. ..
[0080]
　In step S15, AP1 sets the permission/prohibition information so as to indicate that reception is not possible, and the process proceeds to step S13.
[0081]
　In step S13, AP1 starts transmission of the DL packet including the availability information in the header part, and the process proceeds to step S14.
[0082]
　In step S14, the AP1 ends the transmission of the DL packet after the transmission of the data portion of the DL packet to the end, and the processing ends.
[0083]
　FIG. 7 is a flowchart illustrating an example of processing performed by STA#i.
[0084]
　In step S21, STA#i waits for the DL packet to be transmitted from AP1 and starts receiving the DL packet. Then, the process proceeds from step S21 to step S22.
[0085]
　In step S22, STA#i detects the destination of the DL packet from AP1, and when the UL packet for upstream communication is transmitted to AP1, the amount of interference to the destination of the DL packet is held by STA#i, for example. Fixed value or smaller than a first threshold value such as a threshold value notified from AP1.
[0086]
　In step S22, if STA#i determines that the amount of interference with the destination of the DL packet when transmitting the UL packet for upstream communication to AP1 is larger than the first threshold value, the process proceeds to step S28. move on.
[0087]
　In step S28, STA#i waits for the transmission of the UL packet to AP1, and the process ends.
[0088]
　On the other hand, if the STA#i determines in step S22 that the amount of interference of the DL packet with the destination when the UL packet for uplink communication is transmitted to the AP1 is smaller than the first threshold value, the process proceeds to step S22. Proceed to S23.
[0089]
　In step S23, STA#i determines from the availability information included in the header portion of the DL packet from AP1 whether upstream communication, that is, UL packet transmission to AP1 is possible.
[0090]
　In step S23, if STA#i determines that uplink communication is not possible, that is, if the availability information included in the header part of the DL packet from AP1 indicates that reception is not possible, the process proceeds to step S28. Then, as described above, the transmission of the UL packet to AP1 is awaited.
[0091]
　On the other hand, in step S23, if STA#i determines that uplink communication is possible, that is, if the availability information included in the header part of the DL packet from AP1 indicates that reception is possible, the process proceeds to step S23. Proceed to S24.
[0092]
　In step S24, STA#i starts acquisition of the transmission right and sets a random waiting time (random number of time slots) in preparation for transmission of the UL packet to AP1, and the process proceeds to step S25. move on.
[0093]
　As described above, the AP1 does not interfere with the destination transmitting the DL packet (the amount of interference is smaller than the first threshold value), and the availability information of the DL packet received from the AP1 is received. If yes, STA#i starts preparing to send a UL packet to AP1.
[0094]
　In step S25, STA#i waits for the end of backoff (expiration of the time slot), and the process proceeds to step S26.
[0095]
　In step S26, STA#i is a threshold different from the first threshold and exceeds a fixed value held by STA#i or a second threshold such as the threshold notified from AP1 (reception). It is determined whether or not a power signal is being transmitted.
[0096]
　In step S26, if STA#i determines that the signal with the power exceeding the second threshold value is being transmitted, the process proceeds to step S28, and as described above, the UL packet is transmitted to AP1. Is waited for.
[0097]
　On the other hand, when the STA#i determines in step S26 that the signal having the power exceeding the second threshold value is not transmitted, the process proceeds to step S27.
[0098]
　In step S27, STA#i starts transmission of the UL packet to AP1, and after the transmission up to the end of the data portion of the UL packet is completed, the process ends.
[0099]
　As described above, while AP1 transmits the DL packet including the availability information, STA#i determines from the availability information included in the DL packet whether upstream communication, that is, whether the UL packet can be transmitted to AP1. Judge and control the transmission of UL packets. Therefore, in the wireless communication system 10, the occurrence of interference between STAs in full-duplex communication can be reduced.
[0100]
　Specifically, for example, to prevent multiple uplink communication to AP1 occur at the same time, to prevent AP1 from failing to receive the UL packet in the uplink communication, that is, packets are transmitted from multiple STAs. It is possible to avoid the packet collision caused by being performed. Also, AP1 can perform full-duplex communication without collecting information such as the traffic volume of STA#i.
[0101]
　FIG. 8 is a diagram showing a second embodiment of the format of a DL packet transmitted in downlink communication from AP1 (communication device 20) to STA#i (communication device 30 i ).
[0102]
　The DL packet according to the second embodiment includes a plurality of availability information.
[0103]
　In FIG. 8, the horizontal axis represents time and the vertical axis represents frequency.
[0104]
　Further, similar to FIG. 3, the DL packet shown in FIG. 8 is a packet standardized in IEEE802.11ax, for example. Data (MAC) as a data part is arranged in that order and configured.
[0105]
　The permission/prohibition information can be included in the packet in various forms other than being included in the header of the packet. The availability information may be included in one position (position in time or frequency) of the packet, or may be included in multiple positions.
[0106]
　It should be noted that insertion positions, which are positions at a plurality of places where the propriety information is included in the DL packet, are assumed to be predetermined.
[0107]
　For example, the propriety information can be included in the header part or the data part of the packet only once or in plural. Further, one or more pieces of permission/prohibition information can be included in each of the header portion and the data portion of the packet.
[0108]
　Further, as the permission/prohibition information, a signal in a communication band part of the communication band when the DL packet is transmitted, or a part of subcarriers when the DL packet is transmitted may be used. When a signal in a part of the communication band or a part of the subcarrier is used as the availability information, the presence or absence of the signal or the subcarrier indicates that the signal cannot be received or can be received.
[0109]
　When including the propriety information in the header part and the data part of the DL packet, for example, regarding the header part of the DL packet, the propriety information is included in any field of the header part, and regarding the data part of the DL packet, A signal or subcarrier in the communication band corresponding to the data part can be used as the availability information.
[0110]
　As described above, in the header part and the data part of the DL packet, the way of including the permission/prohibition information can be changed.
[0111]
　Further, as described above, by including the availability information in the positions of the DL packet at a plurality of positions, the AP1 changes the status of the uplink communication during the downlink transmission period of the DL packet, and the status of the UL packet reception availability is changed. Even if there is a change, by including the availability information indicating the availability of the changed UL packet in the DL packet during the downlink transmission period, the latest information on the availability of UL packet reception is notified to STA#i. be able to.
[0112]
　As a result, STA#i determines whether or not it is possible to receive the UL packet of AP1 at the current time even during the reception of the DL packet transmitted from AP1, and based on the determination result, the UL to AP1 is judged. The transmission of packets can be controlled.
[0113]
　Here, the DL packet transmitted by the AP1, for example, during the downlink transmission period of the DL packet in which the availability information is included only in one part of the header portion, for example, the data portion of the DL packet is received by STA#i. In this case, when AP1 receives the UL packet, AP1 cannot notify that the UL packet cannot be received.
[0114]
　That is, if the UL packet is receivable, the AP 1 starts transmission of the DL packet including the availability information indicating the receivability in the header part. When one header information is included in the header part of the DL packet transmitted by AP1, STA#i receives the header information of the header part of the DL packet to receive the header information. By indicating the possibility, it is determined that the uplink communication to AP1 is possible, and the transmission of the UL packet is started.
[0115]
　On the other hand, AP1 is, after starting the transmission of the DL packet, if the reception of the UL packet is disabled, for example, after the transmission of the header part of the DL packet, if the reception of the UL packet is disabled, AP1, the next Until the DL packet is transmitted, it cannot be notified by the availability information included in the header of the DL packet that the UL packet cannot be received.
[0116]
　Therefore, as shown in FIG. 8, AP1 can include the availability information at the positions of a plurality of places in the DL packet. For example, by including the permission/prohibition information at one or more positions in the header portion of the DL packet and at one or more positions in the data portion, the AP1 can transmit the UL packet Even when the reception is disabled, it is possible to notify that the UL packet cannot be received by the availability information included in the data portion of the DL packet.
[0117]
　For example, as described in FIG. 5, when STA1 and STA3 are about to start transmitting UL packets, AP1 sets the header section availability information to be receivable, and the DL packet having the header section is set. When STA1 and STA3 receive the availability information indicating the receivability included in the header part of the DL packet from AP1, the STA1 and STA3 start acquiring the transmission right in preparation for the transmission of the UL packet.
[0118]
　Then, as described with reference to FIG. 5, STA1 acquires the transmission right before STA3, and starts the transmission of the UL packet after the transmission of the header portion of the DL packet by AP1 and before the transmission of the data portion. In this case, the AP1 sets the availability information of the data section to be transmitted in the unreceivable state according to the transmission of the UL packet from the STA1 (uplink communication status), and transmits the data section.
[0119]
　Upon receiving such availability information of the data section, the STA3 waits for transmission of the UL packet to the AP1. As a result, it is possible to prevent the UL packet of STA1 and the UL packet of STA3 from colliding due to the STA3 starting to transmit the UL packet to the AP1.
[0120]
　Note that the STA1 cannot receive the data portion of the DL packet from the AP1 including the permission/inhibition information indicating unreceivability by starting the transmission of the UL packet to the AP1. Therefore, STA1 transmits (continues) the UL packet to AP1.
[0121]
　In addition, in FIG. 5, since STA3 has received the DL packet addressed to STA2 from AP1, there is a possibility that STA1 cannot detect that UL packet transmission has started to AP1. If STA3 cannot detect that STA1 is transmitting a UL packet to AP1, STA3 starts transmitting a UL packet to AP1. When STA3 starts transmitting the UL packet to AP1, a collision occurs between the STA1 UL packet and the STA3 UL packet.
[0122]
　In addition, when the received power at the STA3 of the signal that the STA1 is transmitting the UL packet to the AP1 does not exceed the second threshold, the STA3 is transmitting the UL packet to the AP1 by the STA1. Therefore, if the UL packet transmission to AP1 is started, the UL packet of STA1 and the UL packet of STA3 collide with each other.
[0123]
　Therefore, when AP1 receives the UL packet from STA1, according to the reception of the UL packet from STA1 (uplink communication status), for example, the AP1 cannot receive the availability information included in the data portion of the DL packet being transmitted. Set to. The STA3 waits for the transmission of the UL packet when the availability information included in the data portion of the DL packet being received from the AP1 indicates that the reception is not possible. As a result, when STA1 cannot detect the start of UL packet transmission to AP1, STA3 starts transmitting DL packets to AP1, which causes a collision between UL packets of STA1 and UL packets of STA3. Is avoided.
[0124]
　FIG. 9 is a flowchart illustrating an example of processing performed by AP1 when the DL packet of FIG. 8 is transmitted.
[0125]
　In step S31, the AP1 determines whether the UL packet for uplink communication can be received based on whether or not the UL packet for uplink communication is received from the STA#i.
[0126]
　In step S31, when the AP1 determines that the UL packet for uplink communication can be received, that is, when the UL packet is not received from any STA#i, the process proceeds to step S32.
[0127]
　In step S32, AP1 sets the permission/prohibition information so as to indicate that reception is possible, and the process proceeds to step S33.
[0128]
　On the other hand, in step S31, when the AP1 determines that the UL packet for uplink communication cannot be received, that is, when the UL packet is received from any STA#i, the process proceeds to step S37. ..
[0129]
　In step S37, AP1 sets the permission/prohibition information so as to indicate that reception is not possible, and the process proceeds to step S33.
[0130]
　In step S33, AP1 starts transmission of the DL packet including the availability information, and the process proceeds to step S34. In the transmission of the DL packet, the availability information set in step S32 or step S37 is included in the latest insertion position of the DL packet.
[0131]
　In step S34, AP1 determines whether a UL packet has been received from STA#i.
[0132]
　In step S34, when AP1 determines that the UL packet is received from STA#i, that is, when the UL packet is received from any STA#i during the transmission of the DL packet started in step S32, The process proceeds to step S35.
[0133]
　In step S35, the AP 1 sets (changes) the permission/prohibition information so as to indicate that reception is not possible, and the process proceeds to step S36.
[0134]
　On the other hand, in step S34, when AP1 determines that it has not received the UL packet from STA#i, that is, during transmission of the DL packet started in step S32, AP1 transmits the UL packet from any STA#i. If not received, the process proceeds to step S38.
[0135]
In step S38, AP1 sets the permission/prohibition information so as to indicate that reception is possible, and the process proceeds to step S36.
[0136]
　Here, the permission/prohibition information set in step S35 or step S38 is included in the latest insertion position of the DL packet whose transmission is started in step S33.
[0137]
　In step S36, the AP1 ends the transmission of the DL packet after the end of the data portion of the DL packet, and ends the process.
[0138]
　As described above, like the DL packet described in FIG. 8, by including the availability information at multiple positions of the DL packet, even if the situation of upstream communication changes during the transmission of the DL packet, The AP1 can notify the STA#i whether or not the UL packet can be received according to the situation of the upstream communication.
[0139]
　FIG. 10 is a flowchart illustrating an example of processing performed by STA#i when the DL packet of FIG. 8 is transmitted.
[0140]
　In FIG. 10, in steps S41 to S45, processes similar to those in steps S21 to S25 of FIG. 7 are performed.
[0141]
　Then, in step S42, the amount of interference to the destination of the DL packet when the UL packet is transmitted is, for example, a fixed value held by STA#i, or a first threshold value that is a threshold value or the like notified from AP1. When it is determined that the UL packet is larger than the UL packet, and when it is determined in step S43 that the UL packet for upstream communication cannot be transmitted to the AP 1, the process proceeds to step S48.
[0142]
　In step S48, as in step S27 of FIG. 7, STA#i waits for the transmission of the UL packet to AP1, and the process ends.
[0143]
　After the backoff in step S45 is completed, in step S46, STA#i starts reception in step S41, and based on the latest availability information included in the DL packet that is still being received, the STA#i goes up to AP1. Determine whether it is possible to send UL packets for communication.
[0144]
　In step S46, if STA#i determines that the UL packet for uplink communication to AP1 can be transmitted, that is, if the latest availability information included in the DL packet from AP1 indicates that it is receivable. The process proceeds to step S47.
[0145]
　In step S47, STA#i starts transmitting the UL packet to AP1, and after the transmission up to the end of the data portion of the UL packet is completed, the process ends.
[0146]
　On the other hand, in step S46, when STA#i determines that the UL packet for uplink communication to AP1 cannot be transmitted, that is, the latest availability information included in the DL packet from AP1 indicates that reception is not possible. If so, the process proceeds to step S48 to wait for the transmission of the UL packet to AP1, as described above.
[0147]
　As described above, AP1 transmits DL packets including availability information at multiple locations, and STA#i transmits UL packets for uplink communication to AP1 from the latest availability information included in the DL packets. Determine whether it is possible and control the transmission of UL packets to AP1.
[0148]
　Therefore, in the wireless communication system 10, when the AP1 has already received the UL packet from any of the STA#i, the AP1 transmits the DL packet including the availability information indicating the unreceivability, so that a plurality of AP1s are transmitted to the AP1. Preventing uplink communication from occurring at the same time and preventing AP1 from failing to receive UL packets in uplink communication, that is, avoiding packet collisions caused by packets being transmitted from multiple STA#i can do.
[0149]
　Further, as described above, STA#i receives the DL packet including the availability information from the AP1 at a plurality of positions to start the preparation of the transmission of the UL packet to the AP1 and then the UL packet to the AP1. If the availability information indicating the unreceivability is detected before the start of transmission, the UL packet is determined to be untransmittable to the AP1 and the transmission of the UL packet to the AP1 is waited.
[0150]
　Therefore, it is possible to avoid packet collision that occurs when a plurality of STA#i determines that it is possible to transmit UL packets for uplink communication to AP1 and transmits UL packets to AP1.
[0151]
　That is, for example, AP1 starts transmission of a DL packet including availability information at a plurality of positions (each of the header portion and the data portion of the DL packet), and the header portion of the DL packet indicates availability of reception. Shall be included. STA#i determines that it is possible to transmit the UL packet for uplink communication to AP1 by receiving the header part of the DL packet that includes the availability information indicating the receivability in the header part, and responds to the determination. Then, the preparation for transmission of the UL packet for upstream communication to AP1 is started, and the transmission of the UL packet for upstream communication to AP1 is started. When AP1 receives a UL packet whose transmission has started from STA#i, it cannot receive UL packets from other STA#j and receives the availability information to be included in the data part of the DL packet being transmitted. It is set to be disabled, and the data part including such permission/prohibition information is transmitted.
[0152]
　Similar to STA#i, other STA#j other than STA#i also start preparation for transmission of UL packet for upstream communication to AP1 by receiving a header part including availability information indicating receivability. However, before receiving the data from the AP1, it receives the data section including the availability information indicating that the AP1 cannot be received.
[0153]
　As described above, AP1 transmits DL packets including availability information at multiple positions, and STA#i immediately starts transmitting UL packets for upstream communication to AP1, and other STA#j to AP1. It is possible to prevent the UL packet transmission of the upstream communication from being started, and thereby to avoid the collision of the packets of each of STA#i and STA#j.
[0154]
　In the above description, the case where the present technology is applied to the wireless LAN of IEEE 802.11 has been described, but the present technology can be applied to full-duplex communication by wireless other than the wireless LAN of IEEE 802.11.
[0155]
　
[0156]
　Next, the series of processes of the data processing unit 51, the signal processing unit 62, and the like described above can be performed by hardware or software. When a series of processes is performed by software, the program which comprises the software is installed in a computer.
[0157]
　Therefore, FIG. 11 shows a configuration example of an embodiment of a computer in which a program for executing the series of processes described above is installed.
[0158]
　In FIG. 11, a CPU (Central Processing Unit) 201 performs various processes according to a program stored in a ROM (Read Only Memory) 202 or a program loaded from a storage unit 108 into a RAM (Random Access Memory) 203. Execute. The RAM 203 also appropriately stores data necessary for the CPU 201 to execute various processes.
[0159]
　The CPU 201, ROM 202, and RAM 203 are interconnected via a bus 204. An input/output interface 205 is also connected to the bus 204.
[0160]
　The input/output interface 205 includes an input unit 206 including a keyboard and a mouse, a display including an LCD (liquid crystal display), an output unit 207 including a speaker, a storage unit 208 including a hard disk, a modem, and a terminal. A communication unit 209 including an adapter is connected. The communication unit 209 performs communication processing via a network such as the Internet.
[0161]
　A drive 210 is also connected to the input/output interface 205 as necessary, a removable medium 211 such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory is appropriately mounted, and a computer program read from them is It is installed in the storage unit 208 as needed.
[0162]
　The program executed by the computer may be a program that is processed in time series in the order described in this specification, or in parallel or at a necessary timing such as when a call is made. It may be a program in which processing is performed.
[0163]
　The embodiments of the present technology are not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present technology.
[0164]
　It should be noted that the effects described in the present specification are merely examples and are not limited, and may have effects other than those described in the present specification.
　 The
　present technology may have the following configurations.
(1) The 　packet transmitted from the wireless communication terminal 　of the wireless communication system including
　a wireless communication apparatus that functions as a base station
　and one or a plurality of wireless communication terminals that communicate with the wireless communication apparatus as slaves A 　wireless communication device 　comprising: a control unit that sets availability information indicating whether the packet is receivable during a downlink transmission period in which a packet is transmitted from the communication device; and a communication unit that transmits a packet including the availability information . (2) The 　control unit sets the permission/prohibition information so as to indicate receivable or unreceivable according to a situation of upstream communication in which a packet is transmitted from the wireless communication terminal to the wireless communication device 　(1). The wireless communication device according to. (3) The 　radio unit according to 　(1) or (2), wherein the control unit sets the permission/prohibition information so as to indicate whether reception is possible or not according to a situation of the upstream communication during the downstream transmission period. Communication device. (4) 　The packet from the wireless communication device has a header part and a data part,

　The wireless communication device according to
　any one of (1) to (3), wherein the availability information is included in a header portion or a data portion of a packet from the wireless communication device.
(5)
　the packet from the wireless communication device, and a header portion and a data portion,
　the permission information is included in the header portion and the data portion of the packet from the wireless communication device
　(1) to ( The wireless communication device according to any one of 3).
(6)
　A signal in a part of the communication band when the packet from the wireless communication device is transmitted to the wireless communication terminal, or a part of the subcarrier is used as the availability information
　(1). The wireless communication device according to any one of (1) to (5).
(7) The
　wireless communication device according to
　any one of (1) to (6), wherein the availability information is included in a plurality of positions of a packet from the wireless communication device.
(8) The 　packet transmitted from the wireless communication terminal 　of the wireless communication system including
　a wireless communication apparatus that functions as a base station
　and one or more wireless communication terminals that communicate with the wireless communication apparatus as slaves Setting availability information indicating whether or not reception is possible during a downlink transmission period in which a packet is transmitted from the communication device,

　And a packet including the availability information
　.
(9) The 　packet transmitted from the wireless communication terminal 　of the wireless communication system including
　a wireless communication apparatus that functions as a base station
　and one or more wireless communication terminals that communicate with the wireless communication apparatus as slaves During a downlink transmission period in which a packet is transmitted from the communication device, a control unit that controls transmission of the packet to the wireless communication device according to the availability information included in the packet including availability information indicating whether the packet is receivable A 　wireless communication terminal including. (10) 　The packet from the wireless communication device further includes a 　destination, and the control unit controls transmission of the packet to the wireless communication device according to the destination and the availability information 　. Wireless communication terminal. (11) 　When no interference occurs with the destination wireless communication terminal and the availability information indicates receivable, the control unit starts preparation for packet transmission to the wireless communication device. 　The wireless communication terminal according to (9) or (10). (12) The 　availability information is included in a plurality of positions of a packet from the wireless communication device,

　The control unit indicates unreceivability from a packet being received from the wireless communication device after starting preparation of packet transmission to the wireless communication device and before starting packet transmission to the wireless communication device.
　The wireless communication terminal according to any one of (9) to (11), which waits for transmission of a packet to the wireless communication device when the availability information is detected .
(13) The 　packet transmitted from the wireless communication terminal 　of the wireless communication system including
　a wireless communication apparatus that functions as a base station
　and one or more wireless communication terminals that communicate with the wireless communication apparatus as slaves During a downlink transmission period in which a packet is transmitted from the communication device, controlling transmission of the packet to the wireless communication device according to the availability information included in the packet including availability information indicating whether the packet is receivable. A 　wireless communication method including .

Explanation of symbols
[0165]
　10 wireless communication system, 20, 30 communication device, 51 data processing unit, 52 control unit, 53 communication unit, 61 modulation/demodulation unit, 62 signal processing unit, 63 channel estimation unit, 64 i　wireless interface unit, 65 i　amplifier unit, 66 i　antenna, 71 power supply section, 151 data processing section, 152 control section, 153 communication section, 161 modulation/demodulation section, 162 signal processing section, 163 channel estimation section, 164 i　wireless interface section, 165 i　amplifier section, 166 i　antenna, 171 Power supply unit, 201 CPU, 202 ROM, 203 RAM, 204 bus, 205 input/output interface, 206 input unit, 207 output unit, 208 storage unit, 209 communication unit, 210 drive, 211 removable disk
The scope of the claims
[Claim 1]
　From the wireless communication device, 　a packet transmitted from
　the wireless communication device
　of a wireless communication system that includes a wireless communication device that functions as a base station and one or more wireless communication terminals that communicate
with the wireless communication device as slaves. A 　wireless communication device
　comprising: a control unit that sets availability information indicating whether the packet is receivable during a downlink transmission period during which the packet is being transmitted; and a communication unit that transmits a packet including the availability information
.
[Claim 2]
　The control unit sets the permission/prohibition information so as to indicate receivable or unreceivable according to a situation of uplink communication in which a packet is transmitted from the wireless communication terminal to the wireless communication device
　. Wireless communication device.
[Claim 3]

　The wireless communication device according 　to claim 2, wherein the control unit sets the permission/prohibition information so as to indicate whether reception is possible or not according to a situation of the upstream communication during the downstream transmission period .
[Claim 4]
　The wireless communication device according to 　claim 1 ,
　wherein the packet from the wireless communication device has a header part and a data part, and the availability information is included in the header part or the data part of the packet from
the wireless communication device.
[Claim 5]
　The wireless communication according
　to
　claim 1, wherein the packet from the wireless communication device has a header part and a data part, and the availability information is included in the header part and the data part of the packet from the wireless communication device. apparatus.
[Claim 6]
　The signal of a part of the communication band of the packet when the packet from the wireless communication device is transmitted to the wireless communication terminal, or a part of the subcarrier is used as the availability information
　. Wireless communication device.
[Claim 7]
　The wireless communication device according to
　claim 1, wherein the availability information is included in a plurality of positions of a packet from the wireless communication device.
[Claim 8]
　From the wireless communication device, 　a packet transmitted from
　the wireless communication device
　of a wireless communication system that includes a wireless communication device that functions as a base station and one or more wireless communication terminals that communicate
with the wireless communication device as slaves. 　A wireless communication method comprising: setting permission/inhibition information indicating whether or not reception is possible during a downlink transmission period in
　which a packet is transmitted, and transmitting a packet including the permission/inhibition information
.
[Claim 9]
　From the wireless communication device, 　a packet transmitted from
　the wireless communication device
　of a wireless communication system including a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate
with the wireless communication device as slaves. During a downlink transmission period during which a packet is being transmitted, a
　wireless unit including a control unit that controls the transmission of the packet to the wireless communication device according to the availability information included in the packet that includes the availability information indicating whether the packet is receivable. Communication terminal.
[Claim 10]
　The wireless communication terminal
　according to
　claim 9 , wherein the packet from the wireless communication device further includes a destination, and the control unit controls transmission of the packet to the wireless communication device according to the destination and the availability information. ..
[Claim 11]
　It does not cause interference with the wireless communication terminal of the destination, and, when the availability information indicates the idle, the controller starts the preparation for transmission of packets to the wireless communication apparatus
　according to claim 10. The wireless communication terminal according to 10.
[Claim 12]
　The permission/prohibition information is included in a plurality of positions of a packet from the wireless communication device, and the
　control unit transmits a packet to the wireless communication device after starting preparations for transmitting the packet to the wireless communication device.
　The wireless communication terminal according to claim 11, which waits for a packet to be transmitted to the wireless communication device when the availability information indicating unreceivability is detected from a packet being received from the wireless communication device before starting .
[Claim 13]
　From the wireless communication device, 　a packet transmitted from
　the wireless communication device
　of a wireless communication system including a wireless communication device that functions as a base station and one or a plurality of wireless communication terminals that communicate
with the wireless communication device as slaves. A
　wireless communication including controlling transmission of a packet to the wireless communication device according to the availability information included in the packet including availability information indicating whether reception is possible during a downlink transmission period during which the packet is being transmitted. Method.