WO2022029951A1 - Wireless communication device, wireless communication method, and wireless communication system - Google Patents

Abstract

This wireless communication device has a production unit and a transmission unit. The production unit can simultaneously receive a downlink signal from an upper-level wireless communication device and an uplink signal from a lower-level wireless communication device, and produces a control signal for adjusting the transmission timing of the uplink signal in the lower-level wireless communication device such that the reception timing of the uplink signal from the lower-level wireless communication device is later than the transmission timing of the downlink signal in the upper-level wireless communication device. The production unit produces a control signal pertaining to whether or not the transmission power amount of the uplink signal in the lower-level wireless communication device, when simultaneously receiving the downlink signal from the upper-level wireless communication device and the uplink signal from the lower-level wireless communication device, should be increased to be greater than the transmission power amount of the uplink signal in the lower-level wireless communication device when receiving only the uplink signal without receiving the downlink signal. The transmission unit transmits the control signal to the lower-level wireless communication device. Accordingly, it is possible to improve usage efficiency of wireless communication resources of the upper-level wireless communication device and the lower-level wireless communication device.

Description

Wireless communication device, wireless communication method and wireless communication system

The present invention relates to a wireless communication device, a wireless communication method, and a wireless communication system.

In recent years, the communication standard for 5th generation mobile communication (5G or NR (New Radio)) has become even higher in addition to the standard technology for 4th generation mobile communication (4G) (for example, Non-Patent Documents 1 to 11). There is a demand for technology that realizes higher data signal rates, higher capacities, and lower delays. Regarding the 5th generation communication standard, technical studies are underway in the working group of 3GPP (3rd Generation Partnership Project) (for example, TSG-RAN WG1, TSG-RAN WG2, etc.), and the first edition was released in December 2017. (Non-Patent Documents 12 to 39).

In 5G, it is being considered that another base station device relays communication between the base station device and the terminal device. In this relay, a plurality of base station devices arranged between the core network and the terminal device are wirelessly connected, and relay is executed by wireless communication between the base station devices. Such relay in 5G is also called IAB (Integrated Access and Backhaul), and multi-hop relay is allowed.

FIG. 24 is an explanatory diagram showing an example of a wireless communication system 100 including an IAB node 105. The wireless communication system 100 shown in FIG. 24 has a parent node (Parent Node) 102, a child node (Child Node) 103, a UE (User Equipment) 104, and an IAB node 105. The IAB node 105 is a relay device that comprehensively relays an access link with the UE 104 and a BH (Backhaul) between the parent node 102 and the child node 103 by wireless communication (see RP-192188). The BH has a parent BH between the parent node 102 and a child BH between the child node 103.

The IAB node 105 uses the parent BH to receive a DL (Downlink) signal from the parent node 102, and uses the parent BH to transmit a UL (Uplink) signal to the parent node 102. Further, the IAB node 105 uses the child side BH to receive the UL signal from the child node 103, and uses the child side BH to transmit the DL signal to the child node 103. The IAB node 105 uses the access link to receive the UL signal from the UE 104 and also uses the access link to transmit the DL signal to the UE 104.

FIG. 25 is an explanatory diagram showing an example of simultaneous reception processing of the IAB node 105. In Rel (Release) -17, a wireless communication system 100 is proposed in which the IAB node 105 can simultaneously receive the DL signal of the parent BH and the UL signal of the child BH (or access link) as shown in FIG. 25. (See RP-193251).

FIG. 26 is an explanatory diagram showing an example of simultaneous reception timing control of the IAB node 105. The IAB node 105 shown in FIG. 26 has a DL signal of the parent BH from the DU (Distributed Unit) of the parent node 102 and a UL signal of the child BH (or access link) from the child node 103 (or UE 104). Can be received at the same time. When the IAB node 105 can receive the DL signal of the parent BH and the UL signal of the child BH (or access link) at the same time, the IAB node 105 uses wireless communication resources as compared with TDM (Time Division Multiplexing) of Rel-16. Efficiency can be improved. For example, since the reception timing of the UL signal of the child side BH can be used for the transmission timing of the UL signal of the parent side BH, for example, it is possible to improve the utilization efficiency of the wireless communication resource as compared with the TDM. can.

Japanese Unexamined Patent Publication No. 2009-188839 Japanese Patent Publication No. 2014-528226

FIG. 27 is an explanatory diagram showing an example of a problem that the DL signal of the parent BH and the UL signal of the child BH cannot be simultaneously received at the IAB node 105. In the UL timing control of Rel (Release) -16, the reception timing of the UL signal of the child side BH is controlled to be earlier than the transmission timing of the DL signal of the parent side BH. As a result, in the IAB node 105, when the UL timing control of Rel-16 is adopted, the reception timing of the UL (or UL of the access link) signal of the child side BH can be aligned with the reception timing of the DL signal of the parent side BH. It cannot be done, and simultaneous reception processing cannot be realized. As a result, the utilization efficiency of the wireless communication resources of the parent side BH and the child side BH (or access link) is lowered.

Further, even if the IAB node 105 can simultaneously receive the UL signal of the access link and the DL signal of the parent BH, the received power amount of the UL signal of the access link is compared with the received power amount of the DL signal of the parent BH. Becomes smaller. As a result, the reception quality of the UL signal of the access link deteriorates.

FIG. 28 is an explanatory diagram showing an example of a problem when the transmission timing of the UL signal at the IAB node 105 is delayed from the transmission timing of the DL signal. In Rel-16, by aligning the transmission timings of DL signals in all cells in the wireless communication system 100, it is possible to suppress the occurrence of cross-link interference in adjacent nodes. However, when the IAB node 105 simultaneously receives the DL signal of the parent BH and the UL signal of the child BH while aligning the transmission timings of the DL signals in all the cells, the UL signal reception timing is the DL signal. It is later than the transmission timing.

On one aspect, a wireless communication device or the like capable of simultaneously receiving a DL signal of a parent BH and an UL (or UL of an access link) signal of a child BH to improve the utilization efficiency of wireless communication resources is provided. There is something in it.

The wireless communication device of one embodiment has a generation unit and a transmission unit. The generation unit can simultaneously receive the downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device, and the reception timing of the uplink signal from the lower wireless communication device is on the upper side. A control signal for adjusting the transmission timing of the uplink signal in the lower wireless communication device is generated so as to be later than the transmission timing of the downlink signal in the wireless communication device. The transmission unit transmits the control signal to the lower wireless communication device.

In one aspect, it is possible to improve the utilization efficiency of wireless communication resources between the upper wireless communication device and the lower wireless communication device.

FIG. 1 is an explanatory diagram showing an example of the wireless communication system of the first embodiment. FIG. 2 is a block diagram showing an example of the hardware configuration of the parent node. FIG. 3 is a block diagram showing an example of the functional configuration of the parent node. FIG. 4 is a block diagram showing an example of the functional configuration of the child node. FIG. 5 is a block diagram showing an example of the hardware configuration of the IAB node. FIG. 6 is a block diagram showing an example of the functional configuration of the IAB node. FIG. 7 is a block diagram showing an example of the hardware configuration of the UE. FIG. 8 is a block diagram showing an example of the functional configuration of the UE. FIG. 9 is an explanatory diagram showing an example of simultaneous reception timing of the DL signal of the parent BH and the UL signal of the child BH of the IAB node. FIG. 10A is an explanatory diagram showing an example of the relationship between frequency resources of simultaneous reception processing using FDM. FIG. 10B is an explanatory diagram showing an example of the relationship between frequency resources of simultaneous reception processing using SDM. FIG. 11 is an explanatory diagram showing an example of DL / UL allocation slots of IAB-MT and IAB-DU. FIG. 12 is an explanatory diagram showing an example of slot arrangement of the child side BH (access link). FIG. 13 is an explanatory diagram showing an example of transmission / reception timing of IAB-DU. FIG. 14 is an explanatory diagram showing an example of the timing relationship between the IAB-DU and the MT of the child node (or UE). FIG. 15 is an explanatory diagram showing an example of a RAR format configuration including a TA command. FIG. 16 is an explanatory diagram showing an example of a MAC-CE format configuration including a TA command. FIG. 17 is a flowchart showing an example of the processing operation of the IAB node related to the scheduling process. FIG. 18A is an explanatory diagram showing an example of an adjustment table corresponding to 1 bit. FIG. 18B is an explanatory diagram showing an example of a 2-bit compatible adjustment table. FIG. 19 is an explanatory diagram showing an example of the adjustment table. FIG. 20 is an explanatory diagram showing an example of a switching table. FIG. 21A is an explanatory diagram showing an example of a switching table corresponding to 1 bit. FIG. 21B is an explanatory diagram showing an example of a switching table corresponding to 2 bits. FIG. 22 is an explanatory diagram showing an example of the wireless communication system of the second embodiment. FIG. 23 is an explanatory diagram showing an example of simultaneous transmission / reception timing of the IAB node of the second embodiment. FIG. 24 is an explanatory diagram showing an example of a wireless communication system including an IAB node. FIG. 25 is an explanatory diagram showing an example of simultaneous reception processing of the IAB node. FIG. 26 is an explanatory diagram showing an example of simultaneous reception timing control of the IAB node. FIG. 27 is an explanatory diagram showing an example of a problem that the DL signal of the parent BH and the UL signal of the child BH cannot be simultaneously received at the IAB node. FIG. 28 is an explanatory diagram showing an example of a problem when the transmission timing of the UL signal at the IAB node is delayed from the transmission timing of the DL signal.

Hereinafter, the present embodiment will be described in detail with reference to the drawings. The issues and examples in this specification are examples, and do not limit the scope of rights of the present application. In particular, even if the expressions described are different, the techniques of the present application can be applied even if they are technically equivalent, and the scope of rights is not limited. Then, each embodiment can be appropriately combined within a range that does not contradict the processing contents.

Further, as the terms used in this specification and the technical contents described, the terms and technical contents described in the specifications and contributions may be appropriately used as standards related to communication such as 3GPP.

Hereinafter, examples of the wireless communication device, the wireless communication method, and the wireless communication system disclosed in the present application will be described in detail with reference to the drawings. The following examples do not limit the disclosed technology.

FIG. 1 is an explanatory diagram showing an example of the wireless communication system 1 of the first embodiment. The wireless communication system 1 shown in FIG. 1 has a parent node 2, a child node 3, a UE (User Equipment) 4, and an IAB (Integrated Access and Backhaul) node 5. The parent node 2 is not shown, for example, on the upper side of a base station or the like which is connected to the core network by wire communication and is connected to another node such as the IAB node 5 or the UE 4 by wireless communication. It is a wireless communication device. The child node 3 is a lower-level wireless communication device such as a base station that connects to the IAB node 5 and the UE 4 by wireless communication. The UE 4 is a terminal device such as a smartphone or a tablet that connects to the parent node 2, the child node 3, and the IAB node 5 by wireless communication.

The IAB node 5 is a wireless communication device such as a relay device that integrally relays an access link with the UE 4 and a BH (Backhaul) between the parent node 2 and the child node 3 by wireless communication. The BH has a parent BH between the parent node 2 and a child BH between the child node 3.

The IAB node 5 uses the parent BH to receive a DL (Downlink) signal which is a downlink signal from the parent node 2, and also uses the parent BH to transmit a UL (Uplink) signal to the parent node 2. Further, the IAB node 5 uses the child side BH to receive the UL signal which is an uplink signal from the child node 3, and also uses the child side BH to transmit the DL signal to the child node 3. The IAB node 5 uses the access link to receive the UL signal, which is an uplink signal, from the UE 4, and also uses the access link to transmit the DL signal to the UE 4.

FIG. 2 is a block diagram showing an example of the hardware configuration of the parent node 2. For convenience of explanation, the parent node 2 will be described, but since the child node 3 also has substantially the same configuration as the hardware configuration of the parent node 2, by assigning the same reference numerals, the description of the overlapping configuration and operation will be described. Is omitted. The parent node 2 shown in FIG. 2 has an antenna 21, a radio 22, a network IF 23, an auxiliary storage device 24, a main storage device 25, and a processor 26. The radio 22 is a communication device that transmits and receives radio signals through the antenna 21. The network IF 23 is an IF that controls communication with a higher-level station (not shown) or another radio base station. The auxiliary storage device 24 is a device that stores various programs and the like. The main storage device 25 is a device that stores various types of information. The processor 26 includes, for example, a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), a DSP (Digital Signal Processor), and the like, and controls the entire parent node 2.

FIG. 3 is a block diagram showing an example of the functional configuration of the parent node 2. The parent node 2 shown in FIG. 3 includes a network IF unit 23A, a parent wireless communication unit 22A, a parent reception signal baseband processing unit 26A, a parent transmission signal baseband processing unit 26B, and a parent control unit 26C. And have. The network IF unit 23A is a function of the network IF 23 that controls communication with a higher-level station and another radio base station. The parent side wireless communication unit 22A is a function of the radio device 22 that controls the wireless communication of the parent node 2. The parent-side received signal baseband processing unit 26A is a part of the function of the processor 26 that controls the baseband processing of the received signal on the parent node 2 side. The parent side transmission signal baseband processing unit 26B is a part of the function of the processor 26 that controls the baseband processing of the transmission signal on the parent node 2 side. The parent side control unit 26C is a part of the function of the processor 26 that controls the entire parent node 2.

FIG. 4 is a block diagram showing an example of the functional configuration of the child node 3. The child node 3 shown in FIG. 4 includes a network IF unit 33, a child side wireless communication unit 32, a child side received signal baseband processing unit 36A, a child side transmission signal baseband processing unit 36B, and a child side control unit 36C. And have. The network IF unit 33 is a function of the network IF 23 that controls communication with a higher-level station and another radio base station. The child side wireless communication unit 32 is a function of the radio device 22 that controls the wireless communication of the child node 3. The child-side received signal baseband processing unit 36A is a part of the function of the processor 26 that controls the baseband processing of the received signal on the child node 3 side. The child-side received signal baseband processing unit 36A is a signal processing unit that executes baseband processing on a received signal including, for example, DCI (Downlink Control Information), MAC CE, RRC signal, data, and the like. DCI is information contained in PDCCH (Physical Downlink Control Channel). MAC CE, RRC signals, and data are information contained in PDSCH (Physical Downlink Shared Channel). The child side transmission signal baseband processing unit 36B is a part of the function of the processor 26 that controls the baseband processing of the transmission signal on the child node 3 side. The child-side transmission signal baseband processing unit 36B is a processing unit that executes baseband processing of transmission signals related to data, PUSCH (Physical Uplink Shared Channel), PUCCH (Physical Uplink Control Channel), transmission timing, transmission power, etc., for example. be. The child-side control unit 36C is a part of the function of the processor 26 that controls the entire child node 3.

FIG. 5 is a block diagram showing an example of the hardware configuration of the IAB node 5. The IAB node 5 shown in FIG. 5 has an antenna 51, a radio 52, an auxiliary storage device 53, a main storage device 54, and a processor 55. The radio 52 transmits and receives radio signals through the antenna 51. The auxiliary storage device 53 is a device that stores various programs and the like. The main storage device 54 is a device that stores various types of information. The processor 55 includes, for example, a CPU, FPGA, DSP, etc., and controls the entire IAB node 5.

FIG. 6 is a block diagram showing an example of the functional configuration of the IAB node 5. The IAB node 5 shown in FIG. 6 has an IAB side wireless communication unit 52A, an IAB side reception signal baseband processing unit 55A, an IAB side transmission signal baseband processing unit 55B, and an IAB side control unit 55C. The IAB side wireless communication unit 52A is a function of the wireless device 52 that controls the wireless communication of the IAB node 5. The IAB side received signal baseband processing unit 55A is a part of the function of the processor 55 that controls the baseband processing of the received signal on the IAB node 5 side. The IAB side transmission signal baseband processing unit 55B is a part of the function of the processor 55 that controls the baseband processing of the transmission signal on the IAB node 5 side. The IAB side control unit 55C is a function of the processor 55 that controls the entire IAB node 5.

The IAB side reception signal baseband processing unit 55A has an MT (Mobile Termination) reception signal processing unit 551A and a DU (Distributed Unit) reception signal processing unit 552A. The MT reception signal processing unit 551A is a processing unit that controls reception processing of the DL signal of the parent side BH from the parent node 2. The MT reception signal processing unit 551A notifies the IAB side control unit 55C of the reception timing, reception power, and slot arrangement of the DL signal of the parent side BH. The DU reception signal processing unit 552A is a processing unit that controls the reception processing of the UL signal of the access link from the child side BH from the child node 3 or the UE 4. The DU reception signal processing unit 552A notifies the IAB side control unit 55C of the reception timing, reception power, and transmission request of the UL signal of the child side BH and the access link. The IAB side control unit 55C notifies the DU reception signal processing unit 552A of instructions regarding timing control, transmission power control, MCS, resource allocation, etc. required for the UL signal of the child side BH or the access link. The IAB side control unit 55C notifies the DU transmission signal processing unit 552B of instructions regarding timing control, transmission power control, MCS, resource allocation, etc. of the child side BH or the access link.

The IAB side transmission signal baseband processing unit 55B has an MT transmission signal processing unit 551B and a DU transmission signal processing unit 552B. The MT transmission signal processing unit 551B is a processing unit that controls transmission processing of the UL signal of the parent BH to the parent node 2. The DU transmission signal processing unit 552B is a processing unit that controls the transmission processing of the DL signal of the child side BH to the child node 3 or the access link to the UE 4. The MT reception signal processing unit 551A and the MT transmission signal processing unit 551B constitute an IAB-MT5A that controls wireless communication of the parent BH. The DU reception signal processing unit 552A and the DU transmission signal processing unit 552B constitute an IAB-DU5B that controls wireless communication of the child side BH or the access link.

FIG. 7 is a block diagram showing an example of the hardware configuration of UE4. The UE 4 shown in FIG. 7 has an antenna 41, a radio 42, a display device 43, an auxiliary storage device 44, a main storage device 45, and a processor 46. The radio 42 transmits and receives radio signals through the antenna 41. The display device 43 is an output IF of, for example, a display device that displays and outputs various information. The auxiliary storage device 44 is a device that stores various programs and the like. The main storage device 45 is a device that stores various types of information. The processor 46 includes, for example, a CPU, FPGA, DSP, etc., and controls the entire UE 4.

FIG. 8 is a block diagram showing an example of the functional configuration of the UE 4. The UE 4 shown in FIG. 8 has a UE-side wireless communication unit 42A, a UE-side received signal baseband processing unit 46A, a UE-side transmission signal baseband processing unit 46B, and a UE-side control unit 46C. The UE-side wireless communication unit 42A is a function of the radio 42 that controls the wireless communication of the UE 4. The UE-side received signal baseband processing unit 46A is a part of the function of the processor 46 that controls the baseband processing of the received signal on the UE4 side. The UE-side received signal baseband processing unit 46A is a signal processing unit that executes baseband processing on a received signal including, for example, DCI (Downlink Control Information), MAC CE, RRC signal, data, and the like. DCI is information contained in PDCCH (Physical Downlink Control Channel). MAC CE, RRC signals, and data are information contained in PDSCH (Physical Downlink Shared Channel). The UE-side transmission signal baseband processing unit 46B is a part of the function of the processor 46 that controls the baseband processing of the transmission signal on the UE4 side. The UE-side transmission signal baseband processing unit 46B is a processing unit that executes baseband processing of transmission signals related to, for example, data, PUSCH, PUCCH, transmission timing, transmission power, and the like. The UE-side control unit 46C is a part of the function of the processor 46 that controls the entire UE 4.

The IAB side control unit 55C in the IAB node 5 shown in FIG. 6 has a generation unit 551C and a transmission unit 552C. The generation unit 551C can simultaneously receive the DL signal from the parent node 2 which is the upper wireless communication device and the UL signal from the child node 3 (or UE 4) which is the lower wireless communication device, and the child node. The UL signal from the child node 3 (or UE 4) is delayed so that the UL signal reception timing U (Rx) from the 3 (or UE 4) is later than the DL signal transmission timing D (Tx) from the parent node 2. A control signal for adjusting the transmission timing U (tx) is generated. The transmission unit 552C transmits a control signal to the child node 3 (or UE 4) through the IAB side transmission signal baseband processing unit 55B.

The control signal includes instruction information regarding a time shift of the transmission slot timing of the UL signal from the child node 3 (or UE 4) in symbol units. The generation unit 551C receives the UL signal from the child node 3 (or UE 4) that matches the reception timing of the DL signal from the parent node 2, and the second timing is earlier in time in symbol units. The first timing is determined. The second timing is UL timing # 2, which will be described later, and the first timing is UL timing # 1, which will be described later. Further, the generation unit 551C generates a control signal including instruction information regarding the amount of time shift from the first timing to the second timing in symbol units. The transmission unit 552C stores the control signal in the DCI and transmits it to the child node 3 (or UE4).

In the generation unit 551C, the transmission power amount of the UL signal in the child node 3 (or UE4) when the DL signal from the parent node 2 and the UL signal from the child node 3 (or UE4) are simultaneously received is from the parent node 2. A power control signal including power instruction information indicating the transmission power amount of the UL signal is generated so as to be the same as the transmission power amount of the DL signal of. Then, the transmission unit 552C stores the power control signal in the DCI and transmits it to the child node 3 (or UE4).

FIG. 9 is an explanatory diagram showing an example of simultaneous reception timing control of the DL signal of the parent BH and the UL signal of the child BH of the IAB node 5. The DU of the parent node 2 transmits the DL signal of the parent BH to the IAB node 5 based on the reference timing of the DL signal of the parent BH. The IAB-MT5A of the IAB node 5 receives the DL signal of the parent BH from the parent node 2, and the IAB-DU5B of the IAB node 5 receives the UL signal of the child BH from the child node 3. The IAB node 5 receives the UL signal of the child BH from the child node 3 or the UL signal of the access link from the UE 4 at the timing of receiving the DL signal of the parent BH from the parent node 2. Controls the UL signal reception timing. The IAB node 5 has a child node 3 (or a child node 3) so that the UL signal reception timing U (Rx) from the child node 3 (or UE 4) is later than the DL signal transmission timing D (Tx) from the parent node 2. The transmission timing U (tx) of the UL signal from the UE 4) is adjusted.

The IAB node 5 uses, for example, FDM (Frequency Division Multiplexing) or SDM (Space Division Multiplexing) so that the DL signal of the parent BH and the UL signal of the child BH or the access link can be received at the same time. Therefore, the IAB node 5 aligns the FFT (Fast Fourier Transform) timing, that is, the symbol timing, which simultaneously receives the DL signal of the parent BH and the UL signal of the child BH (or access link) using the FDM / SDM. .. As a result, the IAB node 5 can simultaneously receive the DL signal of the parent BH and the UL signal of the child BH (or access link), so that the utilization efficiency of the frequency resource is improved as compared with the TDM mode of Rel-16. can.

FIG. 10A is an explanatory diagram showing an example of the relationship between frequency resources of simultaneous reception processing using FDM. The IAB node 5 can simultaneously receive the DL signal of the parent BH and the UL signal of the child BH (or access link) by using different frequency resources in the FDM method. That is, in the IAB node 5, since the reception timing of the DL signal of the parent BH and the reception timing of the UL signal of the child BH (or access link) are the same, the FFT timing, that is, the symbol timing is the same. become.

FIG. 10B is an explanatory diagram showing an example of the relationship between frequency resources of simultaneous reception processing using SDM. The IAB node 5 can simultaneously receive the DL signal of the parent BH and the UL signal of the child BH (or access link) using different spaces of the SDM method even if the same frequency resource is used. That is, in the IAB node 5, since the reception timing of the DL signal of the parent BH and the reception timing of the UL signal of the child BH (or access link) are the same, the FFT timing, that is, the symbol timing is the same. become.

FIG. 11 is an explanatory diagram showing an example of DL / UL allocation slots of IAB-MT5A and IAB-DU5B. The IAB-MT5A receives the DL signal of the parent BH and transmits the UL signal of the parent BH to and from the parent node 2. The IAB-DU5B receives the UL signal of the child side BH and transmits the DL signal of the child side BH to and from the child node 3. Further, the IAB-DU5B receives the UL signal of the access link and transmits the DL signal of the access link to and from the UE 4.

In the IAB node 5, the slot arrangement information of the DL signal and the UL signal of the child side BH on the IAB-DU5B side is set based on the slot arrangement information of the DL signal and the UL signal of the parent side BH on the IAB-MT5A side. The slot on the IAB-DU5B side has a slot with simultaneous reception that can simultaneously receive the DL signal of the parent BH and the UL signal of the child BH, and a slot without simultaneous reception that receives only the UL signal of the child BH. be.

In the slot with simultaneous reception, when the FDM method is adopted, the DL signal of the parent BH and the UL signal of the child BH (or access link) are simultaneously received using different frequency resources. In this case, the transmission power amount of the UL signal of the child side BH (or access link) is set to the power mode 1 in which the normal transmission power amount that reduces the transmission power amount is sufficient in order to suppress the power interference between adjacent cells. It will be set.

On the other hand, in the simultaneous reception slot adopting the SDM method, the DL signal of the parent BH and the UL signal of the child BH (or access link) are simultaneously received using the same frequency resource and different spaces. become. However, the amount of transmission power of the UL signal of the child side BH (or access link) is smaller than the amount of transmission power of the DL signal of the parent side BH, and the UL signal is affected by the amount of transmission power of the DL signal of the parent side BH. The reception quality of is deteriorated. Therefore, in the slot with simultaneous reception that adopts the SDM method, the difference in the received power amount of the UL signal of the child side BH (or access link) with respect to the received power amount of the DL signal of the parent side BH is within a predetermined range. The power mode 2 is set to increase the transmission power amount of the UL signal of the child side BH (or access link). As a result, the IAB node 5 can suppress the deterioration of the reception quality of the UL signal of the child side BH or the access link.

Further, in the slot without simultaneous reception, the transmission power amount of the UL signal of the child side BH (or access link) is set to the power mode 1 in which the normal transmission power amount is sufficient. The IAB-DU5B stores a power control signal for identifying the power mode 1 or the power mode 2 in the DCI and transmits the power control signal to the child node 3 or the UE 4 according to the slot arrangement information of the child side BH or the access link. The UE 4 or the child node 3 controls the transmission power amount of the UL signal of the access link or the child side BH based on the power mode 1 or the power mode 2 in the power control signal in the received DCI.

FIG. 12 is an explanatory diagram showing an example of slot arrangement of the child side BH (or access link). The child node 3 (or UE4) sets the UL / DL signal allocation slot of the child side BH based on the slot arrangement information from the IAB-DU5B. The child node 3 (or UE 4) sets a slot with simultaneous reception and a slot without simultaneous reception in the UL / DL signal allocation slot of the child side BH.

FIG. 13 is an explanatory diagram showing an example of transmission / reception timing of IAB-DU5B. The IAB-DU5B transmits the DL signal of the child side BH (or access link) at the reference timing. The IAB-DU5B determines UL timing # 2, which is the UL signal reception timing of the child BH (or access link), which is aligned with the reception timing of the DL signal of the parent BH from the parent node 2. The IAB-DU5B considers the propagation delay time to the child node 3 (or the access link UE 4) of the child side BH, the UL / DL switching time of the child side BH (or the access link), and the UL timing # 2. Determines UL timing # 1 which is earlier by an integer number of symbol lengths. For convenience of explanation, for example, one slot has 14 symbols. When the symbol length is ls and the number of integers is n, UL timing # 1 is (UL timing # 2-ls × n).

Further, the IAB-DU5B transmits a control signal including instruction information regarding a symbol-based time shift of the transmission slot timing from the child node 3 or the UE 4 to the IAB-DU5B. The time shift of the transmission slot timing in symbol units is, for example, an offset value from UL timing # 1. The term "transmission slot timing" is used to clarify that the timing of the symbol that performs the UL signal in the slot is shifted. With Rel-15, it is possible to transmit UL signals not only from symbol # 0 in the slot but also from any symbol with any length that does not straddle the slot, but the transmission slot timing referred to here has been shifted. In this case, the UL signal is transmitted with the timing shifted without changing the start symbol or length.

FIG. 14 is an explanatory diagram showing an example of the timing relationship between the IAB-DU5B and the MT of the child node 3 (or UE4). The TA (Timing advance) command is another control signal capable of adjusting the reception timing of the UL signal of the IAB-DU5B by instructing the child node 3 or the UE 4 to adjust the transmission timing of the UL signal by the IAB node 5. The child node 3 (or UE 4) adjusts the UL signal transmission timing according to the content of the TA command. When the child node 3 (or UE 4) first transmits a UL signal to the IAB node 5, it transmits a RACH (Random Access Channel) preamble to the IAB node 5. At this time, the child node 3 (or UE4) transmits the RACH preamble in accordance with the reception timing of the DL signal. When the IAB node 5 receives the RACH preamble from the child node 3 (or UE4), the IAB node 5 transmits a RAR (Random Access Response) including an 11-bit TA command to the child node 3 (or UE4). That is, the 11-bit TA command is information regarding a time shift from the reception timing of the DL signal (that is, the transmission timing of the RACH preamble).

FIG. 15 is an explanatory diagram showing an example of a RAR format configuration including a TA command. The TA command in RAR is used for UL timing control up to Rel-16. In this UL timing control, it is a command to adjust the reception timing of the UL signal of the child side BH (or access link) to be earlier than the transmission timing of the DL signal of the parent side BH. The data packet shown in FIG. 15 has a subheader for identifying the data packet content and a payload for storing the data packet content. RAR is stored in the payload. The RAR shown in FIG. 15 includes a TA command, a UL grant, and the like. The TA command is an 11-bit command including UL timing # 1. RAR will be transmitted by PDSCH (Physical Downlink Shared Channel). The IAB-DU5B transmits RAR to the child node 3 by the DL signal of the child side BH. Further, the IAB-DU5B transmits RAR to the UE 4 by the DL signal of the access link. As a result, the child node 3 acquires UL timing # 1 from the TA command in the received RAR, and sets the transmission timing of the UL signal of the child side BH at UL timing # 1. Further, the UE 4 acquires UL timing # 1 from the TA command in the received RAR, and sets the transmission timing of the UL signal of the access link at UL timing # 1.

FIG. 16 is an explanatory diagram showing an example of the format configuration of MAC-CE including the TA command. MAC-CE (Media Access Control-Control Element) is stored in the payload in the data packet shown in FIG. MAC-CE stores a 6-bit TA command. MAC-CE will be transmitted by PDSCH. The 6-bit TA command is a command used when finely adjusting the current UL transmission timing. The IAB-DU5B transmits MAC-CE to the child node 3 by PDSCH of the DL signal of the child side BH. Further, the IAB-DU5B transmits the MAC-CE to the UE 4 by the PDSCH of the DL signal of the access link. As a result, the child node 3 acquires the adjustment amount from the TA command in the received MAC-CE, and finely adjusts the transmission timing of the UL signal of the child side BH based on the adjustment amount. Further, the UE 4 acquires the adjustment amount from the TA command in the received MAC-CE, and finely adjusts the transmission timing of the UL signal of the access link based on the adjustment amount.

FIG. 17 is a flowchart showing an example of the processing operation of the IAB node 5 related to the scheduling process. The IAB-MT5A in the IAB node 5 establishes a communication connection with the parent node 2 of the parent BH (step S11). The IAB-DU5B in the IAB node 5 determines UL timing # 2, which is the transmission timing of the UL signal of the child BH (or access link) so as to be aligned with the reception timing of the DL signal of the parent BH (step S12). ..

As shown in FIG. 13, the IAB-DU5B has only an integer number of symbols from UL timing # 2 in consideration of the propagation delay time to the child node 3 of the child side BH and the UL / DL switching time of the child side BH. The early UL timing # 1 is determined (step S13). In addition, in the IAB-DU5B, in consideration of the propagation delay time to the UE 4 of the access link, the UL / DL switching time of the access link, and the like, as shown in FIG. 13, the UL timing # 2 is earlier than the UL timing # 2 by an integer number of symbols. Timing # 1 will be decided.

The IAB-DU5B determines the DL / UL allocation slot allocation information of the child BH (or access link) as shown in FIG. 12 based on the DL / UL allocation slot allocation information of the parent BH (step S14). ..

The IAB-DU5B determines whether or not it has detected a RACH preamble for initiating initial access from the child node 3 (or UE4) (step 15). When the IAB-DU5B detects the RACH preamble, the IAB-DU5B stores the time shift for eliminating the difference between the reception timing of the RACH preamble and the UL timing # 1 determined in step S13 in the 11-bit TA command in RAR shown in FIG. Then, the RAR is notified to the child node 3 (or UE4) (step S16). The child node 3 (or UE4) calculates the transmission side timing of UL timing # 1 from the TA command in RAR.

The IAB-DU5B determines whether or not it has detected the continuation of the initial access of the RRC (Radio Resource Control) connection request based on the UL timing # 1 from the child node 3 (or UE4) (step S17). When the IAB-DU5B detects the continuation of the initial access (step S17: Yes), it establishes an RRC connection with the child node 3 (or UE4) (step S18).

After establishing the RRC connection with the child node 3 (or UE4), the IAB-DU5B stores the UL timing # 2 determined in step S12 in the DCI and notifies the child node 3 (or UE4) of the DCI. (Step S19). The UL timing # 2 is converted from the UL timing # 1 into an offset value. Therefore, the IAB-DU5B stores the index value described later corresponding to the offset value from UL timing # 1 in the DCI, and notifies the DCI to the child node 3 (or UE4). The child node 3 (or UE4) extracts the index value in the DCI and determines the UL timing # 2 based on the offset value corresponding to the index value and the UL timing # 1. Further, the IAB-DU5B notifies the child node 3 (or UE4) of the slot arrangement information of the child side BH (or access link) including the slot with simultaneous reception determined in step S14 (step S20). The child node 3 (or UE 4) transmits a UL signal to the IAB node 5 at UL timing # 2 in the case of a slot with simultaneous reception, and UL timing # 1 in the case of a slot without simultaneous reception, based on the slot arrangement information. Sends the UL signal to the IAB node 5. Further, the child node 3 (or UE 4) uses the power mode 2 for the transmission power amount of the UL signal in the case of the slot with simultaneous reception, and the power transmission power amount of the UL signal in the case of the slot without simultaneous reception, based on the slot arrangement information. It will be set to mode 1.

Further, the IAB-DU5B is a scheduling process that sets UL timing # 2 in the slot with simultaneous reception and UL timing # 1 in the slot without simultaneous reception based on the slot arrangement information of UL / DL on the child side BH (or access link). Is executed (step S21). Then, the processing operation shown in FIG. 17 is terminated. That is, the IAB-DU5B executes the scheduling process while switching the UL timings # 1 and # 2. If the IAB-DU5B does not detect the RACH preamble (step S15: No), the IAB-DU5B proceeds to step S15 until it is determined whether or not the RACH preamble has been detected. If the IAB-DU5B does not detect the continuation of the initial access (step S17: No), the IAB-DU5B proceeds to step S17 until it is determined whether or not the continuation of the initial access is detected.

Since the IAB node 5 enables simultaneous reception of the DL signal of the parent BH and the UL signal of the child BH (or access link) without impairing the connection with the IAB node 5 and the UE 4 up to Rel-16. Improve the utilization efficiency of wireless communication resources.

Further, the IAB-DU5B determines the UL timing # 1 based on the UL timing # 2 in the communication (RRC connection) state. Further, the IAB-DU5B sequentially calculates an offset value for adjusting UL timing # 1 according to the movement of the UE 4 or the child node 3. The IAB-DU5B stores the index value corresponding to the offset value in the DCI and transmits the DCI to the UE 4 or the child node 3.

In the IAB node 5 of the first embodiment, the DL signal from the parent node 2 and the UL signal from the child node 3 are simultaneously received, and the UL signal reception timing U (Rx) from the child node 3 is the parent node 2. The UL signal transmission timing of the child node 3 is adjusted so as to be later than the DL signal transmission timing D (Tx) of. As a result, the IAB node 5 aims to improve the utilization efficiency of wireless communication resources for the parent node 2 and the child node 3.

The IAB node 5 can simultaneously receive the DL signal from the parent node 2 and the UL signal from the UE 4, and the reception timing U (Rx) of the UL signal from the UE 4 is the transmission timing of the DL signal at the parent node 2. The transmission timing of the UL signal of the UE 4 is adjusted so as to be slower than U (Tx). As a result, the IAB node 5 aims to improve the utilization efficiency of wireless communication resources for the parent node 2 and the UE 4.

The IAB node 5 receives the UL signal from the child node 3 that matches the reception timing of the DL signal from the parent node 2, and the UL timing # 2 that is earlier in time in symbol units from the UL timing # 2. Determine 1 and. The IAB node 5 generates a control signal including instruction information regarding the amount of time shift from UL timing # 1 to UL timing # 2 in symbol units. As a result, the child node 3 can transmit the UL signal at UL timing # 2 in the case of the slot with simultaneous reception, and can transmit the UL signal at UL timing # 1 in the case of the slot without simultaneous reception.

When the DL signal from the parent node 2 and the UL signal from the child node 3 are simultaneously received by the IAB node 5, the UL signal of the child side BH (or access link) with respect to the received power amount of the DL signal of the parent side BH. A power control signal instructing the power mode 2 instructing an increase in the transmission power amount of the UL signal in the child node 3 is generated so that the difference in the received power amount of the above is within a predetermined range. As a result, the child node 3 controls the transmission power amount of the UL signal in the power mode 2 in the case of the slot with simultaneous reception, and controls the transmission power amount of the UL signal in the power mode 1 in the case of the slot without simultaneous reception. In particular, it is possible to suppress a deterioration in the reception quality of the UL signal due to the influence of the DL signal at the time of the slot with simultaneous reception.

Next, the mode in which the IAB-DU5B notifies the UL timing # 2 to the child node 3 or the UE 4 by DCI will be described below. First, IAB-DU5B notifies UL timing # 2 by DCI with an offset value from UL timing # 1. FIG. 18A is an explanatory diagram showing an example of the adjustment table 71A corresponding to 1 bit. The adjustment table 71A shown in FIG. 18A is a table that manages the offset value in symbol units from UL timing # 1 for each 1-bit index value. It is assumed that the adjustment table 71A is held by the IAB-DU5B, the child node 3 and the UE 4. The offset value from UL timing # 1 is a 0 symbol when the index value is “0”. The offset value from UL timing # 2 is one symbol when the index value is “1”. The IAB-DU5B refers to the adjustment table 71A, stores the index value according to the offset value in the DCI, and transmits the DCI to the child node 3 or the UE 4 (see TS38.212 v16.1.0). The timing designation area in the DCI may be added to the area in the DCI format "0_0", "0_1" or "0_2" including the UL grants of Rel-15 and Rel-16. The child node 3 or the UE 4 extracts the index value corresponding to the offset value in the DCI, and extracts the offset value corresponding to the extracted index value from the adjustment table 71A. The child node 3 or the UE 4 shifts the UL timing # 1 by the offset value based on the offset value of the UL timing # 1 extracted from the adjustment table 71A, and sets the UL timing # 2. Therefore, the child node 3 or the UE 4 sets UL timing # 2 for the slot with simultaneous reception.

In FIG. 18A, for example, a case where two types of offset values of 0 symbol or 1 symbol are expressed by 1 bit is illustrated, but the present invention is not limited to 1 bit, and may be a plurality of bits, for example, 2 bits. The case expressed by is described below.

FIG. 18B is an explanatory diagram showing an example of a 2-bit compatible adjustment table 71B. The adjustment table 71B shown in FIG. 18B is a table that manages the offset value in symbol units from UL timing # 1 for each 2-bit index value. It is assumed that the adjustment table 71B is held by the IAB-DU5B, the child node 3 and the UE 4. The offset value from UL timing # 1 is a 0 symbol when the index value is “00”. The offset value from UL timing # 1 is one symbol when the index value is “01”. The offset value from UL timing # 1 is 2 symbols when the index value is “10”. The offset value from UL timing # 1 is 3 symbols when the index value is “11”. The IAB-DU5B refers to the adjustment table 71B, stores the index value corresponding to the offset value in the DCI, and transmits the DCI to the child node 3 or the UE 4. The child node 3 or the UE 4 extracts the index value in the DCI and extracts the offset value corresponding to the extracted index value from the adjustment table 71B. The child node 3 or the UE 4 shifts the UL timing # 1 by the offset value based on the offset value of the UL timing # 1 extracted from the adjustment table 71B, and sets the UL timing # 2. Therefore, the child node 3 or the UE 4 sets UL timing # 2 for the slot with simultaneous reception.

Further, the IAB-DU5B exemplifies a case where the offset value from UL timing # 1 is stored in the DCI and the UL timing # 2 is notified to the child node 3 or the UE 4 by using the offset value from UL timing # 1. However, it is not limited to this. For example, UL timing # 1 and UL timing # 2 may be directly notified instead of the offset value conversion of UL timing # 1, and the mode thereof will be described below.

FIG. 19 is an explanatory diagram showing an example of the adjustment table 71C. The adjustment table 71C shown in FIG. 19 is a table that manages UL timing for each 1-bit index value. The UL timing is UL timing # 1 when the index value is “0”. The UL timing is UL timing # 2 when the index value is “1”. The IAB-DU5B defines the adjustment table 71C in the RRC. The IAB-DU5B refers to the adjustment table 71C, stores the index value corresponding to the UL timing in the DCI, and transmits the DCI to the child node 3 or the UE 4. The child node 3 or the UE 4 extracts the index value in the DCI and extracts the UL timing corresponding to the extracted index value from the adjustment table 71C. The child node 3 or the UE 4 sets the UL timing extracted from the adjustment table 71C. Therefore, the child node 3 or the UE 4 sets UL timing # 2 for the slot with simultaneous reception.

In FIGS. 18A, 18B and 19, the case where the IAB-DU5B notifies the UL timing # 2 to the child node 3 or the UE 4 at the physical layer of DCI is illustrated, but it may be notified at the MAC layer. The notification at the MAC layer is used when the transmission frequency is lower than that of the PDCCH and it is not necessary to switch in a short period of time such as one slot. For example, the IAB-DU5B may store the number of symbols to be shifted from UL timing # 1 in the MAC-CE which is an extension of the 6-bit TA command, and transmit the MAC-CE to the child node 3 or the UE 4. In this case, the child node 3 or UE 4 extracts the number of symbols from MAC-CE, shifts UL timing # 1 by the number of symbols based on the extracted number of symbols, and sets UL timing # 2. Therefore, the child node 3 or the UE 4 continuously sets the UL timing # 2 until the next instruction regarding the timing arrives, without being aware of whether or not the slot has simultaneous reception.

Further, the IAB-DU5B may store the number of symbols to be shifted from UL timing # 1 in the RAR in addition to the 11-bit TA command, and transmit the RAR to the child node 3 or the UE. In this case, the child node 3 or the UE 4 extracts the number of symbols from the RAR, shifts the UL timing # 1 by the number of symbols based on the extracted number of symbols, and sets the UL timing # 2. Therefore, the child node 3 or the UE 4 sets UL timing # 2 for the slot with simultaneous reception.

FIG. 20 is an explanatory diagram showing an example of the switching table 72. The switching table 72 shown in FIG. 20 is a table that manages the power mode for each 1-bit index value. It is assumed that the switching table 72 is held by the IAB-DU5B, the child node 3 and the UE 4. The power mode 1 is, for example, a power mode of the transmission power amount of the UL signal of the UE 4 or the child node 3 set at the time of the slot without simultaneous reception or the simultaneous reception slot of the FDM method. The power mode 1 is a normal power mode in which the amount of transmission power is suppressed to the minimum in order to suppress cross-link interference between adjacent nodes. The power mode 2 is, for example, a power mode of the transmission power amount of the UL signal of the UE 4 or the child node 3 set at the time of the simultaneous reception slot of the SDM method. In the power mode 2, the UL signal of the child node 3 (or UE 4) is set so that the difference between the received power amount of the DL signal of the parent BH and the UL signal of the child BH (or access link) is within a predetermined range. It is a mode to control the amount of transmission power of. The amount of transmission power of the UL signal is controlled by dividing it into two terms, P0 and P1, as (P0 + P1), for example. P1 is an amount that changes according to the bandwidth to be transmitted and the propagation loss between the IAB node and the child node 3 (or UE4), and P0 is a fixed amount uniquely determined by IAB-DU5B. The amount of transmission power of the UL signal is determined by setting P0 corresponding to each of the power mode 1 and the power mode 2. Further, P0 can be set according to PUCCH and PUSCH. In FIG. 20, power control is performed according to the mode by setting P0 when transmitting the PUSCH in the power mode 1 to P0 and _PUSCH1 and P0 when transmitting the PUSCH in the power mode 2 to P0 and _PUSCH2 . The IAB-DU5B determines the values of P _{0, PUSCH 1} and P 0, PUSCH 2 in advance and notifies the child node 3 (or UE 4) by RRC. The power mode is the power mode 1 when the index value is “0”. The power mode is the power mode 2 when the index value is “1”. The IAB-DU5B refers to the switching table 72, stores the index value corresponding to the power mode in the DCI, and transmits the DCI to the child node 3 or the UE 4. The child node 3 or the UE 4 extracts the index value in the DCI and extracts the power mode corresponding to the extracted index value from the switching table 72. The child node 3 or the UE 4 controls the transmission power amount of the UL signal by setting the power mode extracted from the switching table 72. That is, the IAB-DU5B is the transmission power amount of the UL signal of the child side BH (or access link) when receiving only the UL signal of the child side BH (or access link) without receiving the DL signal of the parent side BH. Is used as a reference, and whether or not it should be increased is controlled by using the index of the switching table.

Note that FIG. 19 illustrates a case where UL timing information is set in the timing designation area in the DCI, and FIG. 20 illustrates a case where the power mode information related to the transmission power is set in the power designation area in the DCI. However, the timing information and the power mode information may be collectively set in the switching area in the DCI. FIG. 21A is an explanatory diagram showing an example of a switching table 72A corresponding to 1 bit. The switching table 72A shown in FIG. 21A is a table that manages the setting contents of the power mode information and the UL timing information for each bit index value. When the index value is "0", the setting contents are UL timing # 1 and power mode 1. When the index value is "1", the setting contents are UL timing # 2 and power mode 2. It is assumed that the switching table 72A is held by the IAB-DU5B, the child node 3 and the UE 4.

The IAB-DU5B refers to the switching table 72A, stores the index value corresponding to the setting content in the DCI, and transmits the DCI to the child node 3 or the UE 4. The child node 3 or the UE 4 extracts the index value in the DCI, and extracts the setting contents corresponding to the extracted index value from the switching table 72A. The child node 3 or the UE 4 sets UL timing information and power mode information, which are the setting contents extracted from the switching table 72A.

FIG. 21B is an explanatory diagram showing an example of a 2-bit compatible switching table 72B. The switching table 72B shown in FIG. 21B is a table that manages the setting contents of the power mode information and the UL timing information for each 2-bit index value. It is assumed that the switching table 72B is held by the IAB-DU5B, the child node 3 and the UE 4. When the index value is "00", the setting contents are UL timing # 1 and power mode 1. When the index value is "01", the setting contents are UL timing # 2 and power mode 1 corresponding to the slot with simultaneous reception of the FDM method. When the index value is "10", the setting contents are UL timing # 2 and power mode 2 corresponding to the slot with simultaneous reception of the SDM method. The IAB-DU5B refers to the switching table 72B, stores the index value corresponding to the set content in the DCI, and transmits the DCI to the child node 3 or the UE 4. The child node 3 or the UE 4 extracts the index value in the DCI, and extracts the setting contents corresponding to the extracted index value from the switching table 72B. The child node 3 or the UE 4 sets UL timing information and power mode information, which are the setting contents extracted from the switching table 72B.

IAB-DU5B exemplifies the case where UL timing information and power mode information are notified to the child node 3 or UE 4 by using DCI of PDCCH. However, the IAB-DU5B is not limited to the case where the UL timing information and the power mode information are notified to the child node 3 or the UE 4 by using DCI, and the IAB-DU5B periodically sets the slot type to the child node using the common PDCCH. Notify 3 or UE4. Then, the child node 3 or the UE 4 may execute UL timing adjustment or power adjustment according to the slot type in the common PDCCH.

Further, the IAB-DU5B exemplifies the case where the UL timing information is adjusted in symbol units, but the UL timing information is used in mini-slot units (mini-slot: 1 symbol or more and less than 1 slot) in which the slots are divided. ), The UL timing may be adjusted in units of 1/2 symbol, 1/4 symbol, etc., which are divided into symbols, and can be changed as appropriate. Further, although the case where DL / UL is set for each slot is illustrated, DL / UL may be set for each mini slot and may be applied to a slot in which both DL and UL exist, and the mini slot for simultaneous reception is performed. UL timing may be adjusted in the same manner.

An example is shown in which the IAB-DU5B notifies the UE 4 or the child node 3 individually by PDCCH about the contents of UL timing adjustment and power adjustment. However, instead of individually notifying the contents of timing adjustment and power adjustment, the UE4 or child node uses RRC in advance to set the slot timing according to the slot type such as the slot with simultaneous reception and the transmission power amount of the UL signal. Notify 3. Then, after notifying the setting in advance, the slot types of one or more slots may be collectively notified using the common PDCCH. The UE 4 may perform one or both of the timing adjustment and the power adjustment according to the slot type of each slot.

Also, instead of the common PDCCH, all slot type specifications may be notified by RRC. Further, the slot type of some slots may be notified by RRC, and the slot type of the remaining slots may be notified by PDCCH.

In the wireless communication system 1 of the first embodiment, one IAB node 5 is arranged between the parent node 2 and the child node 3, and the IAB node 5 is the DL signal of the parent BH and the child BH (or access). The case where the UL signal of the link) can be received at the same time is illustrated. However, three # 1 to # 3 IAB nodes 5 are arranged between the parent node 2 and the child node 3, and the IAB node 5 of # 2 is the DL signal from the IAB-DU5B of # 1 and # 3. UL signal from IAB-MT5A is received at the same time. Further, the IAB node 5 of # 3 may simultaneously transmit and receive the UL signal from the child node 3 while transmitting the UL signal to the IAB-DU5B of # 2. Will be described below.

Further, in the wireless communication system 1 (1A) of the first and second embodiments, the occurrence of unnecessary cross-link interference is suppressed by aligning the transmission timings of the DL signals of the parent node 2 and the IAB node 5 with the reference timing. The efficiency of wireless resource usage can be improved. In this case, setting the UL signal reception timing U (Rx) from the child node 3 (or UE 4) to be later than the DL signal transmission timing D (Tx) from the parent node 2 is to be later than the child node 3 (or UE 4). Alternatively, it is synonymous with setting the reception timing U (Rx) of the UL signal from the UE 4) to be later than the transmission timing of the DL signal from the IAB node 5.

FIG. 22 is an explanatory diagram showing an example of the wireless communication system 1 of the second embodiment. The wireless communication system 1 shown in FIG. 22 has a parent node 2, an IAB node 5 of # 1 to # 3, a child node 3, and a UE 4. The IAB node 5 of # 1 is a child BH between the IAB-MT5A of # 1 that transmits and receives the DL / UL signal of the parent BH to and from the parent node 2 and the IAB node 5 of # 2. It has a # 1 IAB-DU5B that transmits and receives UL / DL signals. The IAB node 5 of # 1 is a first wireless communication device. The IAB node 5 of # 2 is a child between the IAB-MT5A of # 2 and the IAB-MT5A of # 3 which transmit and receive the DL / UL signal of the child side BH to and from the IAB-DU5B of # 1. It has a # 2 IAB-DU5B that transmits and receives DL / UL signals on the side BH. The IAB node 5 of # 2 is a third wireless communication device. The IAB node 5 of # 3 communicates with the IAB-DU5B of # 3, and between the IAB-MT5A of # 3 that transmits and receives the DL / UL signal of the child side BH, and the child node 3 (or UE4). It has a # 3 IAB-DU5B that transmits and receives UL / DL signals of the child side BH. The IAB node 5 of # 3 is a fourth wireless communication device. The child node 3 or UE 4 is a second wireless communication device.

FIG. 23 is an explanatory diagram showing an example of simultaneous transmission / reception timing of the IAB nodes 5 of # 1 to # 3 of the second embodiment. The IAB node 5 of # 2 can simultaneously receive the DL signal from the IAB node 5 of # 1 and the UL signal from the IAB node 5 of # 3, and the reception timing of the UL signal from the IAB node 5 of # 3. The first to adjust the UL signal transmission timing U (Tx) from the # 3 IAB node 5 so that U (Rx) is later than the DL signal transmission timing D (Tx) from the # 1 IAB node 5. Generates the control signal of 1. Further, the IAB node 5 of # 2 uses DCI to transmit the first control signal to the IAB node 5 of # 3.

The IAB node 5 of # 3 receives the UL signal from the child node 3 (or UE4) while transmitting the UL signal to the IAB node 5 of # 2, and the UL signal from the child node 3 (or UE4). The transmission timing U (Tx) of is earlier than the transmission timing U (Tx) of the UL signal to the IAB node 5 of # 2, and the UL signal reception timing U (Rx) from the child node 3 (or UE 4). A second control signal that adjusts the UL signal transmission timing U (Tx) of the child node 3 (or UE 4) so that is later than the transmission timing D (Tx) of the DL signal from the IAB node 5 of # 1. To generate. Further, the IAB node 5 of # 3 uses DCI to transmit a second control signal to the child node 3 (or UE 4).

The IAB node 5 of # 2 can simultaneously receive the DL signal of the parent BH from the IAB-DU5B of # 1 and the UL signal of the child BH from the IAB-MT5A of # 3. Further, the IAB node 5 of # 3 can transmit the UL signal to the IAB-DU5B of # 2 and at the same time receive the UL signal from the child side BH (or access link) from the child node 3 (or UE4). That is, at the same timing, the IAB node 5 of # 3 simultaneously receives the DL signal of the parent BH and the UL signal of the child BH, while the IAB node 5 of # 3 receives the UL signal to the IAB-DU5B of # 2. Can be sent. Further, at the same time, the UL signal from the child side BH (or access link) from the child node 3 (or UE 4) can be received.

In the wireless communication system 1A of the second embodiment, the IAB node 5 of # 3 receives the UL signal while the IAB node 5 of # 2 simultaneously receives the DL signal of the parent BH and the UL signal of the child BH. The case where the UL signal from the child side BH is received at the same time as the transmission is illustrated. However, even if the IAB node 5 of # 2 does not receive the DL signal of the parent BH and the UL signal of the child BH at the same time, the IAB node 5 of # 3 receives the UL signal to the IAB-DU5B of # 2. At the same time as transmitting, the UL signal from the child side BH (or access link) from the child node 3 (or UE 4) may be received. In this case, the IAB node 5 of # 3 receives the UL signal from the child side BH (or access link) from the child node 3 (or UE4) while transmitting the UL signal to the IAB-DU5B of # 2. Moreover, the UL signal transmission timing of the child node 3 is adjusted so that the UL signal transmission timing from the child node 3 is earlier than the UL signal transmission timing to the IAB node 5 of # 2. As a result, it is possible to improve the utilization efficiency of wireless communication resources related to transmission / reception at the same timing.

In the IAB node 5, when the DL signal from the parent node 2 and the UL signal from the child node 3 are simultaneously received, the UL signal of the child side BH (or access link) with respect to the received power amount of the DL signal of the parent side BH. A power control signal indicating the power mode 2 that increases the transmission power amount of the UL signal in the child node 3 may be generated so that the difference in the received power amount of the child node 3 falls within a predetermined range. As a result, the child node 3 controls the transmission power amount of the UL signal in the power mode 2 in the case of the slot with simultaneous reception, and controls the transmission power amount of the UL signal in the power mode 1 in the case of the slot without simultaneous reception. In particular, it is possible to suppress a deterioration in the reception quality of the UL signal due to the influence of the DL signal at the time of the slot with simultaneous reception.

1 Wireless communication system 2 Parent node 3 Child node 4 UE
5 IAB node 55C IAB side control unit 551C generator unit 552C transmitter unit

Claims (11)

1. The downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device can be received at the same time, and the reception timing of the uplink signal from the lower wireless communication device is the upper wireless. A generation unit that generates a control signal for adjusting the transmission timing of the uplink signal in the lower wireless communication device so as to be later than the transmission timing of the downlink signal in the communication device.
   A wireless communication device including a transmission unit that transmits the control signal to the lower level wireless communication device.
2. The generator is
   The wireless communication device according to claim 1, wherein the control signal including instruction information regarding a time shift in a symbol unit of the transmission slot timing of the uplink signal in the lower wireless communication device is generated.
3. The generator is
   The second timing of receiving the uplink signal from the lower wireless communication device that matches the reception timing of the downlink signal from the upper wireless communication device, and the time from the second timing in symbol units. The first timing (UL timing # 1) to be earlier is determined, and the control signal including the instruction information regarding the time shift amount from the first timing to the second timing in symbol units is generated. 2. The wireless communication device according to claim 2.
4. The transmitter is
   The wireless communication device according to claim 2 or 3, wherein the control signal is stored in DCI (Downlink Control Information) and transmitted to the lower level wireless communication device.
5. The generator is
   The transmission power amount of the uplink signal in the lower wireless communication device when the downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device are simultaneously received is described as described above. Generates power control information including power instruction information as to whether or not it should be increased from the transmission power amount of the uplink signal in the lower wireless communication device when receiving only the uplink signal without receiving the downlink signal.
   The transmitter is
   The wireless communication device according to claim 1, wherein the power control information is transmitted to the lower level wireless communication device.
6. The generator is
   Another control signal including instruction information regarding the time shift based on the reception timing of the downlink signal from the wireless communication device in the lower wireless communication device is generated.
   The transmitter is
   The wireless communication device according to claim 2, wherein the other control signal is transmitted to the lower-level wireless communication device.
7. While transmitting the uplink signal to the upper wireless communication device, the uplink signal from the lower wireless communication device is received, and the transmission timing of the uplink signal from the lower wireless communication device is the upper side. A generation unit that generates a control signal for adjusting the transmission timing of the uplink signal of the lower-level wireless communication device so as to be earlier than the transmission timing of the uplink signal to the wireless communication device of the above.
   A wireless communication device including a transmission unit that transmits the control signal to the lower level wireless communication device.
8. When the downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device are simultaneously received, the transmission power amount of the uplink signal in the lower wireless communication device is received. A generation unit that generates power control information including power instruction information as to whether or not to increase the transmission power amount of the uplink signal in the lower wireless communication device when only the uplink signal is received without using the generator.
   A wireless communication device including a transmission unit that transmits the power control information to the lower level wireless communication device.
9. The wireless communication device
   The downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device can be received at the same time, and the reception timing of the uplink signal from the lower wireless communication device is the upper wireless. A control signal for adjusting the transmission timing of the uplink signal of the lower wireless communication device is generated so as to be later than the transmission timing of the downlink signal from the communication device.
   A wireless communication method comprising executing a process of transmitting the control signal to the lower-level wireless communication device.
10. A wireless communication system having a wireless communication device on the upper side, a wireless communication device on the lower side, and a wireless communication device that wirelessly communicates with the wireless communication device on the upper side and also communicates wirelessly with the wireless communication device on the lower side. There,
    The wireless communication device is
    The downlink signal from the upper wireless communication device and the uplink signal from the lower wireless communication device can be received at the same time, and the reception timing of the uplink signal from the lower wireless communication device is the upper side. A generation unit that generates a control signal for adjusting the transmission timing of the uplink signal from the lower wireless communication device so as to be later than the transmission timing of the downlink signal from the wireless communication device of the above.
    A wireless communication system including a transmission unit that transmits the control signal to the lower-level wireless communication device.
11. A first wireless communication device on the upper side, a second wireless communication device on the lower side, and a third wireless communication device arranged between the first wireless communication device and the second wireless communication device. And a fourth wireless communication device, the third wireless communication device wirelessly communicates with the first wireless communication device and also wirelessly communicates with the fourth wireless communication device, and the fourth wireless communication device. The wireless communication device is a wireless communication system that wirelessly communicates with the second wireless communication device and also wirelessly communicates with the third wireless communication device.
    The third wireless communication device is
    The downlink signal from the first wireless communication device and the uplink signal from the fourth wireless communication device can be received at the same time, and the reception timing of the uplink signal from the fourth wireless communication device is the first. A first control signal for adjusting the transmission timing of the uplink signal of the fourth wireless communication device is generated so as to be later than the transmission timing of the downlink signal from the wireless communication device of the fourth wireless communication device. The signal is transmitted to the fourth wireless communication device, and the signal is transmitted to the fourth wireless communication device.
    The fourth wireless communication device is
    While transmitting the uplink signal to the third wireless communication device, the uplink signal from the second wireless communication device is received, and the transmission timing of the uplink signal from the second wireless communication device is the said. The downlink signal is transmitted from the first wireless communication device earlier than the transmission timing of the uplink signal to the third wireless communication device and the reception timing of the uplink signal from the second wireless communication device is earlier than the transmission timing of the uplink signal. A second control signal for adjusting the transmission timing of the uplink signal of the second wireless communication device is generated so as to be later than the timing, and the second control signal is transmitted to the second wireless communication device. A wireless communication system characterized by

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