Patent Publication Number: US-2021168798-A1

Title: Electronic apparatus, wireless communication method, and computer readable storage medium

Description:
The application claims the priority to Chinese Patent Application No.201810909120.1, titled “ELECTRONIC APPARATUS, WIRELESS COMMUNICATION METHOD, AND COMPUTER READABLE STORAGE MEDIUM”, filed on Aug. 10, 2018 with the China National Intellectual Property Administration, which is incorporated herein by reference in its entirety. 
     TECHNICAL FIELD 
     The present disclosure relates to the technical field of wireless communications, and in particular to an electronic apparatus, a wireless communication method, and a computer readable storage medium. More specifically, the present disclosure relates to an electronic apparatus serving as a parent node in an Integrated Access and Backhaul (IAB) wireless communication system, an electronic apparatus serving as a child node in an IAB wireless communication system, a wireless communication method performed by a parent node in an IAB wireless communication system, a wireless communication method performed by a child node in an IAB wireless communication system, and a computer readable storage medium. 
     BACKGROUND 
     IAB is an important technology adopted in the New Radio (NR) communication system. In an IAB system, a donor node (DN) is connected to another node (including a relay node (RN) and a user equipment (UE)) directly or via one or more RNs. A link, between two RNs or between a RN and a DN, is called as a backhaul (BH) link, and a link, between a UE and a RN or between a UE and a DN, is called as an access (AC) link. In the IAB system, a wireless backhaul link can be adopted, that is, both the BH link and the AC link can be implemented wirelessly. Further, in order to improve indicators such as coverage performance, the number of hops between nodes in the IAB system is not limited. With the complex multi-hop structure, many challenges are introduced in the design of the IAB system. 
     In the IAB system, all the nodes are required to be able to operate in a half-duplex mode. That is, the nodes in the IAB system can only receive data or transmit data at the same time, indicating that the nodes in the IAB system cannot receive data and transmit data simultaneously. Due to the limitation of the half-duplex mode in the IAB system, how to design a frame structure for each of the links in the IAB system is a new challenge. 
     In the design of the physical layer of the NR wireless communication system, uplink/downlink configuration at a symbol level is supported. That is, the minimum time granularity of the uplink/downlink configuration in a frame structure is reduced to a symbol. In a time slot, downlink (DL) symbols, uplink (UL) symbols and X symbols (X symbols may be flexibly configured as DL symbols or UL symbols) are included. Different time slot formats have been defined according to the conventional technology. Based on the design of the time slot format, great flexibility can be achieved in the 5G wireless communication system. For example, different ratios between the UL symbols and the DL symbols may be configured according to the features of the data flow in the system. In addition, different subcarrier intervals, such as 15 KHZ, 30 KHZ, 60 KHZ, 120 KHZ, and  240  KHZ, can be adopted in the NR wireless communication system. For systems with different subcarrier intervals, the period of the time slot is different. Different subcarrier intervals are applicable to various scenarios and service flows. Due to the features of the 5G wireless communication system, new challenges are introduced in the design of the frame structure for the IAB system. 
     Therefore, a technical solution for rationally designing a frame structure for the IAB system based on the features of the 5G wireless communication system is provided. 
     SUMMARY 
     A brief summary of the present disclosure is provided hereinafter. The summary is not a comprehensive overview of a full scope or all the features of the present disclosure. 
     According to the present disclosure, an electronic apparatus, a wireless communication method and a computer readable storage medium are provided to optimize the configuration of the time slot format in the IAB system. 
     According to an aspect of the present disclosure, an electronic apparatus in an Integrated Access and Backhaul (IAB) system is provided. The electronic apparatus includes processing circuitry. The processing circuitry is configured to: configure, according to a subcarrier interval of a link between the electronic apparatus and a child node of the electronic apparatus, a time slot format cycle for the link, where the time slot format cycle includes a predetermined number of time slots; and configure, for the link, a time slot format of each of the time slots within one time slot format cycle. 
     According to another aspect of the present disclosure, an electronic apparatus in an Integrated Access and Backhaul (IAB) system is provided. The electronic apparatus includes processing circuitry. The processing circuitry is configured to: receive, from a parent node of the electronic apparatus, a time slot format cycle of a link between the electronic apparatus and the parent node, where the time slot format cycle includes a predetermined number of time slots; receive time slot configuration information from the parent node; and determine, according to the time slot configuration information, a time slot format of each of time slots of the link within one time slot format cycle. 
     According to another aspect of the present disclosure, a wireless communication method performed by an electronic apparatus in an Integrated Access and Backhaul (IAB) system is provided. The method includes: configuring, according to a subcarrier interval of a link between the electronic apparatus and a child node of the electronic apparatus, a time slot format cycle for the link, where the time slot format cycle includes a predetermined number of time slots; and configuring, for the link, a time slot format of each of the time slots within one time slot format cycle. 
     According to another aspect of the present disclosure, a wireless communication method performed by an electronic apparatus in an Integrated Access and Backhaul (IAB) system is provided. The method includes: receiving, from a parent node of the electronic apparatus, a time slot format cycle of a link between the electronic apparatus and the parent node, where the time slot format cycle includes a predetermined number of time slots; 
     receiving time slot configuration information from the parent node; and determining, according to the time slot configuration information, a time slot format of each of time slots of the link within one time slot format cycle. 
     According to another aspect of the present disclosure, a computer readable storage medium is provided. The computer readable storage medium stores computer-executable instructions. The computer-executable instructions, when executed by a computer, cause the computer to perform the wireless communication method according to the present disclosure. 
     With the electronic apparatus, the wireless communication method and the computer readable storage medium according to the present disclosure, the parent node in the IAB system can configure a time slot format cycle and a time slot format for a link according to a subcarrier interval of the link, thereby optimizing the configuration of the time slot format in the IAB system. 
     Further areas of applicability will become apparent from the description provided herein. Descriptions and examples in this summary are only schematic and are not intended to limit the scope of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings described herein only illustrate the selected embodiments, rather than all embodiments. The drawings are not intended to limit the scope of the present disclosure. In the drawings: 
         FIG. 1  is a schematic structural diagram of an IAB system according to an embodiment of the present disclosure; 
         FIG. 2  is a block diagram showing an example of a configuration of an electronic apparatus according to an embodiment of the present disclosure; 
         FIG. 3  is a schematic diagram showing a relationship between a subcarrier interval and a length of a time slot in an NR communication system according to an embodiment of the present disclosure; 
         FIG. 4  is a schematic diagram showing a relationship between a subcarrier interval and a time slot format cycle according to an embodiment of the present disclosure; 
         FIG. 5  is a schematic diagram of information flows in cases that a RN receives information and the RN transmits information according to an embodiment of the present disclosure; 
         FIG. 6  is a schematic diagram showing a limitation of a half-duplex mode to the design of a time slot format in an IAB system; 
         FIG. 7  is a schematic diagram of a design of a time slot format in an IAB system according to an embodiment of the present disclosure; 
         FIG. 8  is a schematic diagram of a design of a time slot format in an IAB system according to an embodiment of the present disclosure; 
         FIG. 9  is a signaling flow chart of configuring, by a parent node, a time slot format cycle and a time slot format for a link according to an embodiment of the present disclosure; 
         FIG. 10  is a signaling flow chart of updating, by a DN, a time slot format of each of links in an IAB system according to an embodiment of the present disclosure; 
         FIG. 11  is a signaling flow chart of updating, by a DN, a time slot format of each of links in an IAB system according to an embodiment of the present disclosure; 
         FIG. 12  is a signaling flow chart of updating, by a RN, a time slot format of each of part of links in an IAB system according to an embodiment of the present disclosure; 
         FIG. 13  is a signaling flow chart of updating, by a RN, a time slot format of each of part of links in an IAB system according to an embodiment of the present disclosure; 
         FIG. 14  is a signaling flow chart of updating, by a RN, a time slot format of each of part of links in an IAB system according to an embodiment of the present disclosure; 
         FIG. 15  is a block diagram showing an example of a configuration of an electronic apparatus according to another embodiment of the present disclosure; 
         FIG. 16  is a flow chart of a wireless communication method performed by an electronic apparatus according to an embodiment of the present disclosure; 
         FIG. 17  is a flow chart of a wireless communication method performed by an electronic apparatus according to another embodiment of the present disclosure; 
         FIG. 18  is a block diagram showing a first example of a schematic configuration of a gNB (Node B in 5G communication system); 
         FIG. 19  is a block diagram showing a second example of a schematic configuration of a gNB; 
         FIG. 20  is a block diagram showing an example of a schematic configuration of a smartphone; and 
         FIG. 21  is a block diagram showing an example of a schematic configuration of a car navigation device. 
     
    
    
     Although the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of examples in the drawings and have been described in detail herein. However, it should be understood that the description of specific embodiments herein is not intended to limit the present disclosure to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. It should be noted that same or similar reference numerals are used throughout the drawings to refer to the same or like parts. 
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     The embodiments of the present disclosure will be described completely in conjunction with the drawings. The following description is only exemplary, and is not intended to limit the present disclosure, and applications or usages thereof 
     Exemplary embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art. Numerous specific details, such as examples of specific components, devices, and methods, are described to provide a detailed understanding of the embodiments of the present disclosure. It is apparent for those skilled in the art that the exemplary embodiments may be implemented in many different forms without specific details, and should not be construed to limit the scope of the present disclosure. In some exemplary embodiments, well-known processes, well-known structures, and well-known technologies are not described in detail. 
       FIG. 1  is a schematic structural diagram of an IAB system according to an embodiment of the present disclosure. The IAB wireless communication system may include multiple nodes, including one DN, one or more RNs, and one or more UEs. In the IAB system, all nodes may be located within a coverage region of the DN. The DN may directly communicate with the RN or the UE, or may communicate with the RN or the UE via one or more RNs. A link, between a RN and a DN or between two RNs, is called as a BH link, and a link, between a UE and a DN or between a UE and a RN is called as an AC link. For any link in the IAB system, a node at one end of the link and close to the DN may be called as a parent node, and a node at the other end of the link may be called as a child node. In the IAB system, each node except the DN has a unique parent node. A node in the IAB system may have no child nodes, one child node, or multiple child nodes. That is, in the IAB system, the parent node may be a DN or a RN, and the child node may be a RN or a UE. 
     As shown in  FIG. 1 , the IAB wireless communication system includes one DN, three RNs (RN 1 , RN 2 , and RN 3 ), and two UEs (UE 1  and UE 2 ). DN directly communicates with RN 1  via a BH 1  link; DN directly communicates with UE 1  via an AC 1  link; DN communicates with RN 2  via RN 1 , the BH 1  link and a BH 2  link; DN communicates with RN 3  via RN 1 , the BH 1  link and a BH 3  link; and DN communicates with UE 2  via RN 1 , the BH 1  link and an AC 2  link. In the embodiment shown in  FIG. 1 , RN 1  and UE 1  may be called as child nodes of DN, and DN may be called as a parent node of RN 1  and UE 1 . Similarly, RN 2 , RN 3  and UE 2  may be called as child nodes of RN 1 , and RN 1  may be called as a parent node of RN 2 , RN 3  and UE 2 . 
     As described above, the structure of the IAB system is illustrated according to the embodiment shown in  FIG. 1 . Since both the BH link and the AC link in the IAB system are implemented wirelessly, the IAB system is called as an IAB wireless communication system in the present disclosure. In addition, since the IAB system is adopted in the 5G NR communication system, the embodiments of the present disclosure can be applied to the 5G NR communication system. 
     The DN according to the present disclosure may be an apparatus at the network side, such as any type of Transmitting and Receiving Point (TRP) or a base station device (such as an eNB or a gNB). 
     The RN according to the present disclosure may be an apparatus at the network side, such as a TRP or a device at the network side having certain functions of a base station device, where the certain functions include but not limited to receiving data from a UE and a DN, transmitting data to a UE and a DN, and configuring certain parameters for a UE. That is, the RN may be a device at the network side, which is arranged within a coverage region of the DN and has certain functions of a base station device. 
     The UE according to the present disclosure may be a mobile terminal (such as a smart phone, a tablet personal computer (PC), a notebook PC, a portable game terminal, a portable/dongle type mobile router, and a digital camera device), or an in-vehicle terminal (such as a car navigation device). The user equipment may also be implemented as a terminal (which is also called as a machine type communication (MTC) terminal) that performs machine-to-machine (M2M) communication. Furthermore, the user equipment may be a wireless communication module (such as an integrated circuit module including a single die) mounted on each of the terminals. 
       FIG. 2  is a block diagram showing an example of a configuration of an electronic apparatus  200  according to an embodiment of the present disclosure. The electronic apparatus  200  may serve as a parent node on any link in the IAB wireless communication system. The electronic apparatus  200  may serve as a DN or a RN in the IAB wireless communication system. 
     As shown in  FIG. 2 , the electronic apparatus  200  may include a cycle configuration unit  210  and a format configuration unit  220 . 
     All the units of the electronic apparatus  200  may be included in processing circuitry. It should be noted that the electronic apparatus  200  may include one processing circuitry or multiple processing circuitry. Further, the processing circuitry may include various discrete functional units to perform various functions and/or operations. It should be noted that the functional units may be physical entities or logical entities, and units with different titles may be implemented by the same physical entity. 
     According to an embodiment of the present disclosure, the cycle configuration unit  210  may configure, according to a subcarrier interval of a link between the electronic apparatus  200  and a child node of the electronic apparatus, a time slot format cycle for the link. The time slot format cycle includes a predetermined number of time slots. 
     According to the embodiment of the present disclosure, the cycle configuration unit  210  may, during a child node initially accesses the IAB system, configure the time slot format cycle for the link between the electronic apparatus  200  and the child node. During the child node initially accesses the IAB system, a parent node of the child node may be determined. 
     The parent node may determine the subcarrier interval of the link between the parent node and the child node and indicate the subcarrier interval to the child node through system information, which is not described in detail in the present disclosure. In addition, since the electronic apparatus  200  may have one child node or multiple child nodes, the cycle configuration unit  210  may configure a time slot format cycle for a link between the electronic apparatus  200  and each of the child nodes. In the present disclosure, the time slot format cycle may indicate a cycle within which a time slot format is configured. Taking the time slot format cycle of two time slots as an example, the time slot format is configured within a cycle of two time slots. 
     According to an embodiment of the present disclosure, the format configuration unit  220  may further configure, for the link between the electronic apparatus  200  and the child node, a time slot format of each of the time slots within one time slot format cycle. 
     That is, the format configuration unit  220  may configure the time slot format for the link within a period of a time slot format cycle. Still taking the time slot format cycle of two time slots as an example, the format configuration unit  220  may configure the time slot formats of a first time slot and a second time slot before the first time slot, configure the time slot formats of a third time slot and a fourth time slot before the third time slot, and configure the time slot formats of a fifth time slot and a sixth time slot before the fifth time slot. If the time slot formats of the third time slot and the fourth time slot are the same as the time slot formats of the first time slot and the second time slot respectively, the configuration of the time slot formats of the third time slot and the fourth time slot may be omitted. Similarly, since the electronic apparatus  200  may have one child node or multiple child nodes, the format configuration unit  220  may configure a time slot format for a link between the electronic apparatus  200  and each of the child nodes. 
     It is known that, in a case of using a normal Cyclic Prefix (CP), each of the time slots includes 14 OFDM symbols; and in a case of using an extended CP, each of the time slots includes 12 OFDM symbols. For convenience of explanation, only the case in which each of the time slots includes 14 OFDM symbols is taken as an example for description in the present disclosure. According to an embodiment of the present disclosure, the time slot format of each of the time slots may include uplink/downlink configuration information of each of the 14 OFDM symbols included in the time slot, indicating whether each of the 14 OFDM symbols is a DL symbol, a UL symbol or an X symbol. Thus, the format configuration unit  220  may configure the time slot format of each of the time slots within one time slot format cycle for the link, that is, the format configuration unit  220  may configure the type (DL, UL, or X) of each of the OFDM symbols for the link within one slot format cycle. 
     Therefore, the electronic apparatus  200  according to the present disclosure may configure a time slot format cycle and a time slot format for a link according to a subcarrier interval of the link, thereby optimizing the configuration of the time slot format in the IAB system. 
     In the 5G NR communication system, different links are allowed to have different subcarrier intervals. The subcarrier interval may be configured as 15×2 μ KHZ, where μ represents a non-negative integer. For example, if μ is respectively set to 0, 1, 2, 3, and 4, the subcarrier interval is respectively equal to 15 KHZ, 30 KHZ, 60 KHZ, 120 KHZ, and  240  KHZ. Further, for different subcarrier intervals, one time slot includes 14 OFDM symbols, and each of the OFDM symbols has a different length in time domain. That is, for links with different subcarrier intervals, each of the time slots has a different length in the time domain. 
       FIG. 3  is a schematic diagram showing a relationship between a subcarrier interval and a length of a time slot in an NR communication system according to an embodiment of the present disclosure.  FIG. 3  shows a length of a time slot in the time domain in cases that μ is respectively set to 0, 1, 2, 3, and 4. In  FIG. 3 , the shaded portion represents a length of a time slot. As shown in  FIG. 3 , in a case that μ is set to 0 (the subcarrier interval is equal to 15 KHZ), the length of a time slot in the time domain is equal to 1 ms, that is, a subframe having a length of 1 ms includes one time slot; in a case that μ is set to 1 (the subcarrier interval is equal to 30 KHZ), the length of a time slot in the time domain is equal to 500 μs, that is, the subframe having a length of 1 ms includes two time slots; in a case that μ is set to 2 (the subcarrier interval is equal to 60 KHZ), the length of a time slot in the time domain is equal to 250 μs, that is, the subframe having a length of 1 ms includes four time slots; in a case that μ is set to 3 (the subcarrier interval is equal to 120 KHZ), the length of a time slot in the time domain is equal to 125μs, that is, the subframe having a length of 1 ms includes eight time slots; and in a case that μ is set to 4 (the subcarrier interval is equal to 240 KHZ), the length of a time slot in the time domain is equal to 62.5 μs, that is, the subframe having a length of 1 ms includes sixteen time slots. Therefore, a greater subcarrier interval indicates that a time slot has a shorter length in the time domain and the subframe having a length of 1 ms includes more time slots. 
     According to an embodiment of the present disclosure, the cycle configuration unit  210  may configure a time slot format cycle for a link such that the subcarrier interval of the link is proportional to the number of the time slots included in the time slot format cycle. That is, a greater subcarrier interval of the link indicates that a greater number of time slots are included in one time slot format cycle of the link. 
     According to an embodiment of the present disclosure, the cycle configuration unit  210  may configure the length of the time slot format cycle of the link in the time domain to be equal to a length of a time slot format cycle of a link between the electronic apparatus  200  and a parent node of the electronic apparatus  200  in the time domain, or equal to a length of a time slot format cycle of a link between the electronic apparatus  200  and another child node of the electronic apparatus  200  in the time domain. 
     According to an embodiment of the present disclosure, the time slot format cycle for each of the links in the IAB system may have the same length in the time domain. In an embodiment, the length of the time slot format cycle in the time domain may be equal to a multiple of the length (1 ms) of a subframe. In another embodiment, the length of the time slot format cycle in the time domain may be equal to the length of a subframe, that is, 1 ms. 
       FIG. 4  is a schematic diagram showing a relationship between a subcarrier interval and a time slot format cycle according to an embodiment of the present disclosure. According to the embodiment shown in  FIG. 4 , the length of the time slot format cycle in the time domain may be equal to the length of a subframe, that is, 1 ms. As shown in  FIG. 4 , in a case that the subcarrier interval is equal to 15 KHZ, the subframe having a length of 1 ms includes one time slot, thus the time slot format cycle is equal to 1; in a case that the subcarrier interval is equal to 30 KHZ, the subframe having a length of 1 ms includes two time slots, thus the time slot format cycle is equal to 2; in a case that the subcarrier interval is equal to 60 KHZ, the subframe having a length of 1 ms includes four time slot, thus the time slot format cycle is equal to 4; in a case that the subcarrier interval is equal to 120 KHZ, the subframe having a length of 1 ms includes eight time slots, thus the time slot format cycle is equal to 8; and in a case that the subcarrier interval is equal to 240 KHZ, the subframe having a length of 1 ms includes sixteen time slots, thus the time slot format cycle is equal to 16. That is, in cases that μ is respectively set to 0, 1, 2, 3, and 4, the cycle configuration unit  210  may respectively configure the time slot format cycle as 1, 2, 4, 8, and 16. 
     As shown in  FIG. 2 , the electronic apparatus  200  may further include a communication unit  230 . The communication unit  230  is configured to transmit and receive information. 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may periodically transmit the time slot format cycle to the child node by using the communication unit  230 . For example, the electronic apparatus  200  may transmit the time slot format cycle through high layer signaling. The high level signaling includes but is not limited to RRC signaling. Table 1 shows a non-limiting example of a field of slotformat_cycle indicating the time slot format cycle which is added in the RRC signaling, and a value of the field. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Field 
                 Value 
               
               
                   
                   
               
             
            
               
                   
                 slotformat_cycle 
                 {1, 2, 4, 8, 16} 
               
               
                   
                   
               
            
           
         
       
     
     For example, the electronic apparatus  200  may add the following codes in the RRC signaling of UL-DL-Configuration-common, UL-DL-Configuration-common-set2, and UL-DL-Configuration-dedicate: 
     
       
         
           
               
               
             
               
                   
               
             
            
               
                 TDD-UL-DL-SlotConfig::= 
                 SEQUENCE{ 
               
            
           
           
               
               
               
            
               
                   
                 slotIndex 
                 TDD-UL-DL-SlotIndex, 
               
            
           
           
               
               
               
            
               
                   
                 slotformatcycle 
                 ENUMERATED {1,2,4,8,16} 
               
            
           
           
               
               
               
            
               
                   
                 symbols 
                 CHOICE { 
               
            
           
           
               
               
               
            
               
                   
                  allDownlink 
                  NULL, 
               
               
                   
                  allUplink 
                  NULL, 
               
            
           
           
               
               
               
            
               
                   
                  explicit 
                 SEQUENCE} 
               
            
           
           
               
               
               
            
               
                   
                 nrofDownlinkSymbols 
                 INTEGER 
               
            
           
           
               
            
               
                 (1..maxNrofSymbols-1) 
               
            
           
           
               
               
               
            
               
                   
                  nrofUplinkSymbols 
                 INTEGER (1..maxNrofSymbols-1) 
               
            
           
           
               
               
            
               
                   
                  } 
               
               
                   
                 } 
               
            
           
           
               
            
               
                 } 
               
               
                   
               
            
           
         
       
     
     As described above, the cycle configuration unit  210  may configure the time slot format cycle for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 . Further, the cycle configuration unit  210  may transmit the configured time slot format cycle to the format configuration unit  220 , so that the format configuration unit  220  can configure, according to the time slot format cycle, the time slot format of each of the time slots within the time slot format cycle. The operations by the format configuration unit  220  are described in detail below. 
       FIG. 5  is a schematic diagram of information flows in cases that a RN receives information and the RN transmits information according to an embodiment of the present disclosure. 
     The upper part of  FIG. 5  is a schematic diagram of information flows in a case that a RN receives information. Taking RN 2  as an example, RN 2  cannot transmit information when receiving information. RN 2  may receive information from RN 3 , UE 1 , and RN 1 . The direction of the BH link between RN 2  and RN 3  is uplink, the direction of the AC link between RN 2  and UE 1  is uplink, and the direction of the BH link between RN 2  and RN 1  is downlink. Similarly, the lower part of  FIG. 5  is a schematic diagram of information flows in a case that the RN transmits information. RN 2  cannot receive information when transmitting information. RN 2  may transmit information to RN 3 , UE 1 , and RN 1 . The direction of the BH link between RN 2  and RN 3  is downlink, the direction of the AC link between RN 2  and UE 1  is downlink, and the direction of the BH link between RN 2  and RN 1  is uplink. Therefore, at the same time, a direction of a link between a node and a parent node of the node is opposite to a direction of a link between the node and a child node of the node. Further, if the node has multiple child nodes, links between the node and the multiple child nodes have the same direction. 
     According to an embodiment of the present disclosure, the format configuration unit  220  may configure the time slot format for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 , to cause uplink/downlink configuration of each of symbols within the time slot format cycle to be opposite to uplink/downlink configuration of a corresponding symbol within the time slot format cycle of the link between the electronic apparatus  200  and a parent node of the electronic apparatus  200 , or to be the same as uplink/downlink configuration of a corresponding symbol within the time slot format cycle of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200 . 
     According to the embodiment of the present disclosure, in a case that the electronic apparatus  200  is a RN, the electronic apparatus  200  has a parent node, thus the format configuration unit  220  may configure the time slot format for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 , to cause the uplink/downlink configuration of each of the symbols within the time slot format cycle to be opposite to the uplink/downlink configuration of the corresponding symbol within the time slot format cycle of the link between the electronic apparatus  200  and the parent node of the electronic apparatus  200 . That is, for a symbol, if the uplink/downlink configuration of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200  is UL, the uplink/downlink configuration of the link between the electronic apparatus  200  and the child node is configured as DL; if the uplink/downlink configuration of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200  is DL, the uplink/downlink configuration of the link between the electronic apparatus  200  and the child node is configured as UL; and if the uplink/downlink configuration of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200  is XL, the uplink/downlink configuration of the link between the electronic apparatus  200  and the child node is configured as X. 
     According to the embodiment of the present disclosure, in a case that the electronic apparatus  200  is a DN, the electronic apparatus  200  has no parent node, thus the format configuration unit  220  may configure the time slot format for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 , to cause the uplink/downlink configuration of each of the symbols within the time slot format cycle to be the same as the uplink/downlink configuration of the corresponding symbol within the time slot format cycle of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200 . That is, for a symbol, if the uplink/downlink configuration of the link between the electronic apparatus  200  and another child node of the electronic apparatus  200  is UL, DL, or X, the uplink/downlink configuration of the link between the electronic apparatus  200  and the child node is configured as UL, DL, or X respectively. The format configuration unit  220  may configure a time slot format for each of the links between the electronic apparatus  200  and all the child nodes, so that all the links have the same uplink/downlink configuration. 
       FIG. 6  is a schematic diagram showing a limitation of a half-duplex mode to the design of a time slot format in an IAB system. As shown in  FIG. 6 , it is assumed that the subcarrier interval of the BH 2  link shown in  FIG. 1  is 15 KHZ, the subcarrier interval of the BH 3  link shown in  FIG. 1  is 60 KHZ, and the subcarrier interval of the AC 2  link shown in  FIG. 1  is 120 KHZ, and all links have the same time slot format in which the first 7 symbols are DL symbols and the last 7 symbols are UL symbols, thus  FIG. 6  shows the configurations of the time slot formats of all the links within a subframe having a length of 1 ms. As shown in the dashed box in  FIG. 6 , at the same time, the directions of the BH 2  link and the AC 2  link are downlink, indicating that RN 1  transmits data; and the direction of the BH 3  link is uplink, indicating that RN 1  receives data. However, RN 1  cannot transmit and receive data simultaneously in the half-duplex mode. Therefore, the time slot format is unreasonable. 
       FIG. 7  and  FIG. 8  are schematic diagrams of designs of a time slot format in an IAB system according to embodiments of the present disclosure. In  FIG. 7 , DL symbols, UL symbols, and X symbols are included. In  FIG. 8 , only DL symbols and UL symbols are included. As shown in  FIG. 7  and  FIG. 8 , the BH 2  link, the BH 3  link and the AC 2  link have the same direction at any time. Although X symbols having an uncertain uplink/downlink direction are included in  FIG. 7 , the parent node may notify the child node of the uplink/downlink configuration of the X symbols after the time slot format is configured. The configuration of the X symbols follows a rule for configuring the time slot format, that is, uplink/downlink configuration of a link between a node and a parent node of the node is opposite to uplink/downlink configuration of a link between the node and a child node of the node, and uplink/downlink configuration of links between a node and each of child nodes of the node is the same. 
     As described above, according to the embodiment of the present disclosure, in the 
     IAB system, the uplink/downlink configuration of the link between a node and the parent node of the node is opposite to the uplink/downlink configuration of the link between the node and the child node of the node, and the uplink/downlink configuration of the links between the node and each of the child nodes of the node is the same. Thus, at any time, the directions of the links between a node and all child nodes of the node are the same, and are opposite to the direction of the link between the node and the parent node of the node, ensuring that the node is either transmitting or receiving information, thereby meeting the requirements of the half-duplex mode of the IAB system. 
     As shown in  FIG. 2 , the electronic apparatus  200  may further include a generation unit  240  according to the embodiment of the present disclosure. The generation unit  240  is configured to generate time slot configuration information. The time slot configuration information may indicate information of the time slot format of each of the time slots within one time slot format cycle for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 . Further, the electronic apparatus  200  may transmit the time slot configuration information to the child node via the communication unit  230 . 
     As shown in  FIG. 2 , the electronic apparatus  200  may further include a format management unit  260  according to the embodiment of the present disclosure. The format management unit  260  is configured to manage the time slot format of each of the links (including the link between the electronic apparatus  200  and the parent node of the electronic apparatus  200 , and the links between the electronic apparatus  200  and the child nodes of the electronic apparatus  200 ) related to the electronic apparatus  200 . After the electronic apparatus  200  configures the time slot format for the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 , the electronic apparatus  200  may store the time slot format in the format management unit  260  in addition to transmitting the time slot format to the child node. Thus, both the electronic apparatus  200  and the child node of the electronic apparatus  200  know the time slot format of the link between the electronic apparatus  200  and the child node of the electronic apparatus  200 , so that the electronic apparatus  200  and the child node of the electronic apparatus  200  can transmit uplink/downlink information according to the time slot format. 
     According to the embodiment of the present disclosure, the generation unit  240  may generate time slot configuration information such that the time slot configuration information includes identification information of the time slot format of each of the time slots within one time slot format cycle. Taking a time slot format cycle including four time slots as an example, the generation unit  240  may generate the following time slot configuration information: identification information of a time slot format  1 , identification information of a time slot format  2 , identification information of a slot format  3 , and identification information of a time slot format  4 . 
     According to the current 3GPP standard, 56 different time slot formats have been defined, numbered from 0 to 55 respectively. For each of the time slot formats, the types of the 14 symbols included therein, including UL symbols, DL symbols, or X symbols, are respectively defined. For the time slot formats in which the types of the symbols have been defined, except for the time slot format numbered 0 (in which 14 symbols are DL symbols) and the time slot format numbered 1 (in which 14 symbols are UL symbols), each of the remaining time slot formats includes UL symbols , DL symbols and X symbols. 
     According to an embodiment of the present disclosure, the generation unit  240  may, after the format configuration unit  220  configures the time slot format of each of the time slots, determine whether the time slot format of the time slot is included in the defined 56 time slot formats. If the time slot format of the time slot is included in the defined 56 time slot formats, the generation unit  240  may determine the number of the identification information of the time slot format as the number of the time slot format, ranging from 0 to 55. If the time slot format of the time slot is not included in the defined 56 time slot formats, the generation unit  240  may define the number of the identification information of the time slot format of the time slot as 2. In the time slot format numbered 2, all the 14 symbols are X symbols. 
     Taking the embodiment shown in  FIG. 7  as an example, for the BH 2  link, the time slot format cycle includes one time slot, and the time slot format of the time slot is DL, DL, DL, DL, DL, DL, X, X, UL, UL, UL, UL, UL, UL. This time slot format is included in the defined 56 time slot formats, corresponding to number 45. Thus, the generation unit  240  may generate time slot configuration information corresponding to the time slot format 45. 
     Similarly, for the BH 3  link, the time slot format of a first time slot is all DLs, and this time slot format is included in the defined 56 time slot formats, corresponding to number 0; the time slot format of a second time slot is DL, DL, DL, DL, DL, DL, DL, DL, DL, DL, X, X, X, X, and this time slot format is included in the defined 56 time slot formats, corresponding to number 6; the time slot format of a third time slot is X, X, X, X, UL, UL, UL, UL, UL, UL, UL, UL, UL, UL, and this time slot format is included in the defined 56 time slot formats, corresponding to number 13; and the time slot format of a fourth time slot is all ULs, and this time slot format is included in the defined 56 time slot formats, corresponding to number 1. Therefore, the generation unit  240  may generate time slot configuration information including numbers 0, 6, 13, and 1, respectively. 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may further, if the time slot format indicated by the time slot configuration information generated by the generation unit  240  includes an X symbol, transmit information about configuration of the X symbol to the child node. In an embodiment, the electronic apparatus  200  may transmit the information through low layer signaling, including but not limited to DCI. The electronic apparatus  200  may transmit the information about the configuration of the X symbol by using various known means, which is not limited in the present disclosure. 
     According to the embodiment of the present disclosure, the generated time slot configuration information is simple and clear, compatible with the existing standards, and with minor changes to the existing standards. In addition, in this case, the X symbols are allowed to be included in the time slot format, thereby making the configuration of the time slot more flexible. 
     According to an embodiment of the present disclosure, in order to save signaling overhead, the time slot configuration information generated by the generation unit  240  may include identification information of each of one or more time slots in which uplink/downlink conversion occurs within one time slot format cycle, and identification information of a time slot format of the time slot. 
     As shown in  FIG. 8 , for the BH 2  link, uplink/downlink conversion occurs within one time slot format cycle, and the conversion occurs in a first time slot; for the BH 3  link, uplink/downlink conversion occurs within one time slot format cycle, and the conversion occurs in a second time slot; and for the AC 2  link, uplink/downlink conversion occurs within one time slot format cycle, and the conversion occurs in a fourth time slot. Therefore, as long as the time slot configuration information includes the identification information of the time slot in which the conversion occurs and the time slot format of the time slot, the child node can know the uplink/downlink configuration of each of the symbols within the time slot format cycle.  FIG. 8  only shows the situation in which one uplink/downlink conversion occurs within one time slot format cycle. In fact, multiple uplink/downlink conversions may occur within one time slot format cycle. In this case, the time slot configuration information includes identification information of a time slot in which each of the multiple uplink/downlink conversions occurs and a time slot format of each of the time slots. 
     According to an embodiment of the present disclosure, the communication unit  230  may transmit the identification information of each of the one or more time slots in which uplink/downlink conversion occurs to the child node through high layer signaling, including but not limited to RRC signaling. Table 2 shows a non-limiting example of a field of slotformat transposition indicating identification information of a time slot in which uplink/downlink conversion occurs and a value of the field, where the field of slotformat transposition is added in the RRC signaling. Since one slot format cycle includes at most 16 time slots, a maximum value of slotformat transposition is 16. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 Field 
                 Value 
               
               
                   
                   
               
             
            
               
                   
                 slotformat_transposition 
                 {1, 2, . . . , 16} 
               
               
                   
                   
               
            
           
         
       
     
     In an embodiment, the electronic apparatus  200  may add the following codes in the RRC signaling such as UL-DL-Configuration-common, UL-DL-Configuration-common-set2, and UL-DL-Configuration-dedicate. 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 TDD-UL-DL-SlotConfig::= 
                 SEQUENCE{ 
               
            
           
           
               
               
               
            
               
                   
                  slotIndex 
                 TDD-UL-DL-SlotIndex, 
               
            
           
           
               
               
               
            
               
                   
                  slotformatcycle 
                  ENUMERATED{1,2,4,8,16} 
               
            
           
           
               
               
               
            
               
                   
                 slotformattransposition 
                  INTEGER(1..16) 
               
            
           
           
               
               
               
            
               
                   
                  symbols 
                 CHOICE{ 
               
            
           
           
               
               
               
            
               
                   
                  allDownlink 
                 NULL, 
               
            
           
           
               
               
               
            
               
                   
                  allUplink 
                 NULL, 
               
            
           
           
               
               
               
            
               
                   
                  explicit 
                 SEQUENCE{ 
               
            
           
           
               
               
               
            
               
                   
                 nrofDownlinkSymbols 
                 INTEGER 
               
            
           
           
               
               
            
               
                 (1..maxNrofSymbols-1) 
                 OPTIONAL,-- 
               
            
           
           
               
            
               
                 Need S 
               
            
           
           
               
               
               
            
               
                   
                 nrofUplinkSymbols 
                 INTEGER 
               
            
           
           
               
               
            
               
                 (1..maxNrofSymbols-1) 
                 OPTIONAL -- 
               
            
           
           
               
            
               
                 Need S 
               
            
           
           
               
               
            
               
                   
                  } 
               
               
                   
                 } 
               
            
           
           
               
               
            
               
                   
                 } 
               
               
                   
                   
               
            
           
         
       
     
     According to an embodiment of the present disclosure, the communication unit  230  may transmit the identification information of the time slot format of each of the one or more time slots in which uplink/downlink conversion occurs to the child node through low layer signaling, including but not limited to DCI. 
     As described above, according to the current 3GPP standard, 56 different time slot formats have been defined, numbered from 0 to 55 respectively. In transmitting the identification information of the time slot format of the time slot in which the uplink/downlink conversion occurs to the child node, the time slot format may be not included in the 56 time slot formats. Therefore, in order to further save overhead, some new time slot formats are defined according to the present disclosure, and the new time slot formats are numbered, so that the electronic apparatus  200  may only transmit the number of the time slot format in transmitting the identification information of the time slot format of the time slot in which the uplink/downlink conversion occurs to the child node. In addition, for convenience of explanation, that only one uplink/downlink conversion occurs within one time slot format cycle is taken as an example for description below. It should be understood by those skilled in the art that the solutions according to the present disclosure can also be applied to a situation in which multiple uplink/downlink conversions occurs within one time slot format cycle. 
     Table 3 shows some new time slot formats. 
     
       
         
           
               
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 Num- 
                   
               
               
                 ber 
                 Time slot format 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 56 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 57 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 58 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 59 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 60 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 61 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 62 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 63 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 64 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
                 U 
               
               
                 65 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
                 U 
               
               
                 66 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
                 U 
               
               
                 67 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
                 U 
               
               
                 68 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 U 
               
               
                   
               
            
           
         
       
     
     It can be seen that 13 new time slot formats are defined in Table 3, numbered from 56 to 68. In the time slot formats, DL symbols are arranged in the front, UL symbols are arranged in the back, and the number of the DL symbols is set to 1 to 13, respectively. Therefore, the electronic apparatus  200  may directly transmit the number of the time slot format in transmitting the identification information of the time slot format of the time slot in which the uplink/downlink conversion occurs to the child node of the electronic apparatus  200 . 
     According to the embodiment of the present disclosure, as shown in  FIG. 2 , the electronic apparatus  200  may further include a storage unit  250 . The storage unit  250  is configured to store a correspondence between the time slot formats newly defined according to the present disclosure and the numbers. 
     In addition, as mentioned above, the format configuration unit  220  may configure the uplink/downlink configuration of the link between the electronic apparatus  200  and the child node to be the same as the uplink/downlink configuration of the link between the electronic apparatus  200  and another child node. In order to further simplify the calculation performed by the format configuration unit  220 , a mapping table may be generated according to an embodiment of the present disclosure to map the number of the time slot in which uplink/downlink conversion occurs at different subcarriers and the number of the time slot format of the time slot. Thus, the format configuration unit  220  may determine, according to the number of the time slot in which uplink/downlink conversion occurs of the configured link between the electronic apparatus  200  and the child node and the number of the time slot format of the time slot, the number of a time slot in which uplink/downlink conversion occurs of a to-be-configured link and the number of a time slot format of the time slot. 
     According to the embodiment of the present disclosure, for different subcarrier intervals, the number of the time slots included in one time slot format cycles is different, thus the number of the DL symbols included in the time slot format cycle is different. Table 4 shows the number of the DL symbols included in one time slot format cycle for each of the newly added time slot formats for different subcarrier intervals. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 4 
               
               
                   
               
               
                 Number of time slot 
                   
                   
                   
                   
                   
               
               
                 format in case of μ = 0 
                 μ = 0 
                 μ = 1 
                 μ = 2 
                 μ = 3 
                 μ = 4 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 56 
                 1 
                 2 
                 4 
                 8 
                 16 
               
               
                 57 
                 2 
                 4 
                 8 
                 16 
                 32 
               
               
                 58 
                 3 
                 6 
                 12 
                 24 
                 48 
               
               
                 59 
                 4 
                 8 
                 16 
                 32 
                 64 
               
               
                 60 
                 5 
                 10 
                 20 
                 40 
                 80 
               
               
                 61 
                 6 
                 12 
                 24 
                 48 
                 96 
               
               
                 62 
                 7 
                 14 
                 28 
                 56 
                 112 
               
               
                 63 
                 8 
                 16 
                 32 
                 64 
                 128 
               
               
                 64 
                 9 
                 18 
                 36 
                 72 
                 144 
               
               
                 65 
                 10 
                 20 
                 40 
                 80 
                 160 
               
               
                 66 
                 11 
                 22 
                 44 
                 88 
                 176 
               
               
                 67 
                 12 
                 24 
                 48 
                 96 
                 192 
               
               
                 68 
                 13 
                 26 
                 52 
                 104 
                 208 
               
               
                   
               
            
           
         
       
     
     As shown in Table 4, in a case that μ is equal to 0, one time slot format cycle includes one time slot, thus the number of the DL symbols included in the time slot format cycle is equal to the number of the DL symbols included in the time slot format of the time slot; in a case that μ is equal to 1, one time slot format cycle includes two time slots, thus the number of the DL symbols included in the time slot format cycle is equal to twice the number of the DL symbols included in the time slot format of the time slot; and so on. 
     According to the embodiment of the present disclosure, the number of the DL symbols included in one time slot format cycle shown in Table 4 is divided by 14 to obtain a remainder, then the obtained quotient is added by one to obtain the number of the time slot in which uplink/downlink conversion occurs, and the obtained remainder is equal to the number of the DL symbols included in the time slot in which uplink/downlink conversion occurs. Table 5 shows the number of the DL symbols included in the time slot in which uplink/downlink conversion occurs for different subcarrier intervals and different time slot format numbers. 
     
       
         
           
               
               
               
               
               
               
             
               
                 TABLE 5 
               
               
                   
               
               
                 Number of time slot 
                   
                   
                   
                   
                   
               
               
                 format in case of μ = 0 
                 μ = 0 
                 μ = 1 
                 μ = 2 
                 μ = 3 
                 μ = 4 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
            
               
                 56 
                 1 
                 2 
                 4 
                 8 
                 2 
               
               
                 57 
                 2 
                 4 
                 8 
                 2 
                 4 
               
               
                 58 
                 3 
                 6 
                 12 
                 10 
                 6 
               
               
                 59 
                 4 
                 8 
                 2 
                 4 
                 8 
               
               
                 60 
                 5 
                 10 
                 6 
                 12 
                 10 
               
               
                 61 
                 6 
                 12 
                 10 
                 6 
                 12 
               
               
                 62 
                 7 
                 0 
                 0 
                 0 
                 0 
               
               
                 63 
                 8 
                 2 
                 4 
                 8 
                 2 
               
               
                 64 
                 9 
                 4 
                 8 
                 2 
                 4 
               
               
                 65 
                 10 
                 6 
                 12 
                 10 
                 6 
               
               
                 66 
                 11 
                 8 
                 2 
                 4 
                 8 
               
               
                 67 
                 12 
                 10 
                 6 
                 12 
                 10 
               
               
                 68 
                 13 
                 12 
                 10 
                 6 
                 12 
               
               
                   
               
            
           
         
       
     
     According to the number of the DL symbols included in the time slot in which uplink/downlink conversion occurs, the number of the time slot in which uplink/downlink conversion occurs shown in Table 3 can be determined. For example, in a case that μ is equal to 0, the number of the DL symbols in the time slot in which uplink/downlink conversion occurs is 1, corresponding to the time slot format numbered 56 in Table 3; in a case that μ is equal to 1, the number of the DL symbols in the time slot in which uplink/downlink conversion occurs is 2, corresponding to the time slot format numbered 57 in Table 3; in a case that μ is equal to 2, the number of the DL symbols in the time slot in which uplink/downlink conversion occurs is 4, corresponding to the time slot format numbered 59 in Table 3; and so on. Thus, Table 6 can be determined. Table 6 shows a mapping relationship between the number of the time slot in which uplink/downlink conversion occurs and the number of the time slot format of the time slot at different subcarriers, where “None” indicates that there is no time slot in which uplink/downlink conversion occurs. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 6 
               
             
            
               
                   
               
               
                 μ = 0 
                 μ = 1 
                 μ = 2 
                 μ = 3 
                 μ = 4 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
               
               
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
               
               
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 1 
                 56 
                 1 
                 57 
                 1 
                 59 
                 1 
                 63 
                 2 
                 57 
               
               
                 1 
                 57 
                 1 
                 59 
                 1 
                 63 
                 2 
                 57 
                 3 
                 59 
               
               
                 1 
                 58 
                 1 
                 61 
                 1 
                 67 
                 2 
                 65 
                 4 
                 61 
               
               
                 1 
                 59 
                 1 
                 63 
                 2 
                 57 
                 3 
                 59 
                 5 
                 63 
               
               
                 1 
                 60 
                 1 
                 65 
                 2 
                 61 
                 3 
                 67 
                 6 
                 65 
               
               
                 1 
                 61 
                 1 
                 67 
                 2 
                 65 
                 4 
                 61 
                 7 
                 67 
               
               
                 1 
                 62 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
               
               
                 1 
                 63 
                 2 
                 57 
                 3 
                 59 
                 5 
                 63 
                 10 
                 57 
               
               
                 1 
                 64 
                 2 
                 59 
                 3 
                 63 
                 6 
                 57 
                 11 
                 59 
               
               
                 1 
                 65 
                 2 
                 61 
                 3 
                 67 
                 6 
                 65 
                 12 
                 61 
               
               
                 1 
                 66 
                 2 
                 63 
                 4 
                 57 
                 7 
                 59 
                 13 
                 63 
               
               
                 1 
                 67 
                 2 
                 65 
                 4 
                 61 
                 7 
                 67 
                 14 
                 65 
               
               
                 1 
                 68 
                 2 
                 67 
                 4 
                 65 
                 8 
                 61 
                 15 
                 67 
               
               
                   
               
            
           
         
       
     
     As shown in Table 6, the time slot number represents the number of the time slot in which uplink/downlink conversion occurs, and the time slot format number represents the number of the time slot format of the time slot in which uplink/downlink conversion occurs. For example, in a case that μ is equal to 0, the time slot number is 1 and the time slot format number is  56 , it indicates that uplink/downlink conversion occurs in a first time slot and the time slot format of the time slot is the time slot format numbered  56  shown in Table 3. In a case that μ is equal to 1, uplink/downlink conversion occurs in a first time slot and the time slot format of the time slot is the time slot format numbered  57  shown in Table 3. 
     According to an embodiment of the present disclosure, the storage unit  250  may store, for example, in the case that the DL symbols are arranged in the front, the mapping relationship between the number of the time slot in which uplink/downlink conversion occurs and the number of the time slot format of the time slot for different subcarriers as shown in Table 6. Thus, the format configuration unit  220  may configure the time slot format for other links according to the time slot format of the configured link and the mapping relationship stored in the storage unit  250 . 
     The embodiment shown in  FIG. 8  is taken as an example. Assuming that RN 1  has configured the time slot format of each of the time slots within one time slot format cycle for the BH 2  link, it is required to configure a time slot format for the BH 3  link and the AC 2  link according to the time slot format of the BH 2  link. As shown in  FIG. 8 , for the BH 2  link, in a case that μ is equal to 0, the number of the time slot in which uplink/downlink conversion occurs is 1, and the number of the time slot format of the time slot is  61 . According to Table 6, for the BH 3  link, it can be determined that in the case that μ is equal to 2, the number of the time slot in which uplink/downlink conversion occurs is 2, and the number of the time slot format of the time slot is  65 ; and for the AC 2  link, in the case that μ is equal to 3, the number of the time slot in which uplink/downlink conversion occurs is 4, and the number of the time slot format of the time slot is  61 . 
     In the newly added time slot formats shown in  FIG. 3 , the DL symbols are arranged in the front, and the UL symbols are arranged in the back. Similarly, according to the embodiment of the present disclosure, some new time slot formats in which the UL symbols are arranged in the front and the DL symbols are arranged in the back may be added, as shown in Table 7. 
     
       
         
           
               
               
             
               
                 TABLE 7 
               
               
                   
               
               
                 Num- 
                   
               
               
                 ber 
                 Time slot format 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 69 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 70 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 71 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 72 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 73 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 74 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 75 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 76 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 77 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 78 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
               
               
                 79 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
               
               
                 80 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
                 D 
               
               
                 81 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 U 
                 D 
               
               
                   
               
            
           
         
       
     
     As shown in Table 7, 13 new time slot formats are defined, numbered from  69  to  81 . In the time slot formats, UL symbols are arranged in the front, DL symbols are arranged in the back, and the number of the UL symbols is set to 1 to 13, respectively. Therefore, the electronic apparatus  200  may directly transmit the number of the time slot format in transmitting the identification information of the time slot format of the time slot in which the uplink/downlink conversion occurs to the child node of the electronic apparatus  200 . Similarly, the storage unit  250  may be configured to store the newly added time slot formats. 
     Further, according to the embodiments of the present disclosure, a mapping relationship, in the case that the UL symbols are arranged in the front, between the number of the time slot in which uplink/downlink conversion occurs and the number of the time slot format of the time slot for different subcarriers may be determined in a similar way as described above. The mapping relationship is shown in Table 8. 
     
       
         
           
               
               
               
               
               
             
               
                 TABLE 8 
               
             
            
               
                   
               
               
                 μ = 0 
                 μ = 1 
                 μ = 2 
                 μ = 3 
                 μ =4 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
                 time 
                 time slot 
               
               
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
                 slot 
                 format 
               
               
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
                 number 
               
               
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
            
               
                 1 
                 69 
                 1 
                 70 
                 1 
                 72 
                 1 
                 76 
                 2 
                 70 
               
               
                 1 
                 70 
                 1 
                 72 
                 1 
                 76 
                 2 
                 70 
                 3 
                 72 
               
               
                 1 
                 71 
                 1 
                 74 
                 1 
                 80 
                 2 
                 78 
                 4 
                 74 
               
               
                 1 
                 72 
                 1 
                 76 
                 2 
                 70 
                 3 
                 72 
                 5 
                 76 
               
               
                 1 
                 73 
                 1 
                 78 
                 2 
                 74 
                 3 
                 80 
                 6 
                 78 
               
               
                 1 
                 74 
                 1 
                 80 
                 2 
                 78 
                 4 
                 74 
                 7 
                 80 
               
               
                 1 
                 75 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
                 None 
               
               
                 1 
                 76 
                 2 
                 70 
                 3 
                 72 
                 5 
                 76 
                 10 
                 70 
               
               
                 1 
                 77 
                 2 
                 72 
                 3 
                 76 
                 6 
                 70 
                 11 
                 72 
               
               
                 1 
                 78 
                 2 
                 74 
                 3 
                 80 
                 6 
                 78 
                 12 
                 74 
               
               
                 1 
                 79 
                 2 
                 76 
                 4 
                 70 
                 7 
                 72 
                 13 
                 76 
               
               
                 1 
                 80 
                 2 
                 78 
                 4 
                 74 
                 7 
                 80 
                 14 
                 78 
               
               
                 1 
                 81 
                 2 
                 80 
                 4 
                 78 
                 8 
                 74 
                 15 
                 80 
               
               
                   
               
            
           
         
       
     
     According to an embodiment of the present disclosure, the storage unit  250  may store, for example, in the case that the UL symbols are arranged in the front, the mapping relationship between the number of the time slot in which uplink/downlink conversion occurs and the number of the time slot format of the time slot for different subcarriers as shown in Table 8. Thus, the format configuration unit  220  may configure the time slot format for other links according to the time slot format of the configured link and the mapping relationship stored in the storage unit  250 . The process is similar to the previous process in the case that the DL symbols are arranged in the front, and is not repeated herein. 
     According to an embodiment of the present disclosure, the generated time slot configuration information may only include the number of the time slot in which uplink/downlink conversion occurs and the number of the time slot format of the time slot, thereby saving signaling overhead. Furthermore, in this case, the time slot format does not include an X symbol, thereby avoiding subsequent signaling overhead for indicating the direction of the X symbol. 
       FIG. 9  is a signaling flow chart of configuring, by a parent node, a time slot format cycle and a time slot format for a child node according to an embodiment of the present disclosure. As shown in  FIG. 9 , in step S 901 , a parent node configures a time slot format cycle for a link between the parent node and a child node. In step S 902 , the parent node configures a time slot format of each of the time slots within one time slot format cycle for the link. In step S 903 , the parent node periodically transmits the time slot format cycle of the link to the child node. In step S 904 , the parent node transmits the time slot format of each of the time slots within one time slot format cycle of the link to the child node. Thus, the child node can obtain the time slot format cycle of the link between the child node and the parent node and the time slot format of each of the time slots within the time slot format cycle. 
     As described above, according to the embodiment of the present disclosure, the parent node in the IAB system can configure, for the link between the parent node and the child node, the time slot format cycle and the time slot format of each of the time slots within the time slot format cycle. The process is usually performed during the initial access of the child node. Then, each of the nodes in the IAB system may perform uplink/downlink information transmission according to the configured time slot format cycle and the configured time slot format. The update of the time slot format of all or part of the links in the IAB system is described below. 
     According to an embodiment of the present disclosure, the DN can update a time slot format for each of links in the IAB system. That is, the DN can configure an updated time slot format of each of the time slots within one time slot format cycle for each of the links in the IAB system, and transmit updated time slot configuration information to corresponding nodes, where the corresponding nodes includes two nodes at both ends of a link. The updated time slot configuration information indicates information of the updated time slot format of each of the time slots within one time slot format cycle. 
     According to an embodiment of the present disclosure, in a case that the electronic apparatus  200  is a DN, the format configuration unit  220  may update the time slot format according to one or more of the following information: location information of each of nodes in the IAB system, beam direction of each of the nodes in the IAB system, Buffer Status Report (BSR) messages, traffic volume, and priority of a data packet of each of the nodes in the IAB system. 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may, before transmitting the updated time slot configuration information to other nodes in the IAB system, transmit update request information to the other nodes. In an embodiment, the update request information includes update starting time of the updated time slot format. The update starting time may indicate starting time for updating the time slot formats of all the links in the IAB system. Further, the update starting time should be at a beginning of a time slot format cycle. Assuming that the time slot format cycle is equal to a length of a subframe, that is, 1 ms, the update starting time may indicate from which subframe the updated time slot format is adopted. For example, the electronic apparatus  200  may transmit the update request information to other nodes through high layer signaling including but not limited to RRC signaling. 
     Table 9 shows an example of a field required to be added in the RRC signaling and a value of the field, where slotformat_changetime indicates update starting time of an updated time slot format. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 9 
               
               
                   
                   
               
               
                   
                 Field 
                 Value 
               
               
                   
                   
               
             
            
               
                   
                 slotformat_changetime 
                 BIT STRING 
               
               
                   
                   
               
            
           
         
       
     
     For example, the electronic apparatus  200  may add the following codes in the RRC signaling such as UL-DL-Configuration-common, UL-DL-Configuration-common-set2, and UL-DL-Configuration-dedicate: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 TDD-UL-DL-ConfigCommon::= 
                 SEQUENCE{ 
               
            
           
           
               
               
               
            
               
                   
                  referenceSubcarrierSpacing 
                 SubcarrierSpacing 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
               
               
            
               
                   
                  dl-UL-TransmissionPeriodicity 
                 ENUMERATED 
                 {ms0p5, 
               
            
           
           
               
               
            
               
                 ms0p625, ms1, ms1p25, ms2, ms2p5, ms5, ms10} 
                 OPTIONAL, 
               
            
           
           
               
               
               
            
               
                   
                  nrofDownlinkSlots 
                 INTEGER(0..maxNrofSlots) 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
               
            
               
                   
                  nrofDownlinkSymbols 
                 INTEGER 
               
            
           
           
               
            
               
                 (0..maxNrofSymbols-1) 
               
            
           
           
               
               
               
            
               
                   
                 OPTIONAL, 
                 -- Need R 
               
            
           
           
               
               
               
            
               
                   
                  nrofUplinkSlots 
                 INTEGER (0..maxNrofSlots) 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
            
               
                   
                 nrofUplinkSymbols 
               
            
           
           
               
               
               
            
               
                   
                 INTEGER(0..maxNrofSymbols-1) 
                 slotformatchangetime 
               
            
           
           
               
               
               
            
               
                   
                 BIT STRING 
                 (SIZE (3-4)) } 
               
               
                   
                   
               
            
           
         
       
     
     According to an embodiment of the present disclosure, the electronic apparatus  200  may transmit update request information to all the other nodes in the IAB system, and receive update response information from the other nodes. That is, if other nodes receive the update request information, the other nodes may transmit the update response information to the electronic apparatus  200 , so that the electronic apparatus  200  may determine whether all the other nodes have received the update request information. 
     According to an embodiment of the present disclosure, the update response information may indicate whether a node itself, or the node itself and a child node of the node (if possible, further including a child node of the child node) have received the update request information. In a case that the node has no child nodes, the node may transmit ACK information to a parent node of the node after the node receives the update request information; and in a case that the node has child nodes, the node may transmit the ACK information to the parent node of the node after the node receives ACK information from all the child nodes, or the node may transmit NACK information to the parent node of the node if any one of the child nodes does not feed the update response information (or feeds NACK information). Therefore, the update response information from a node may indicate whether all nodes below the node have received the update request information. 
     According to an embodiment of the present disclosure, if the update response information indicates that one or more other nodes have not received the update request information, the update request information is retransmitted to the one or more other nodes. The electronic apparatus  200  transmits the updated time slot configuration information to all the other nodes in the IAB system if the update response information indicates that all the other nodes have received the update request information. 
     As described above, according to the embodiment of the present disclosure, the electronic apparatus  200  transmits the updated time slot configuration information to all nodes if all the nodes have received the update request information including the update starting time. Thus, it can be ensured that all the nodes in the IAB system can obtain the update starting time, so that the time slot formats are updated at the update starting time. 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may transmit the updated time slot configuration information to all other nodes, for example, through low layer signaling (including but not limited to DCI). 
     According to an embodiment of the present disclosure, the format management unit  260  in the electronic apparatus  200  may, after the electronic apparatus  200  transmits the updated time slot configuration information to all the other nodes, update the time slot format of the links related to the electronic apparatus  200  at the update starting time. Accordingly, each of the other nodes updates the time slot format of the link related to the node itself at the update starting time. 
       FIG. 10  and  FIG. 11  are signaling flow charts of updating, by a DN, a time slot format of each of nodes in an IAB system according to an embodiment of the present disclosure. In  FIG. 10  and  FIG. 11 , the IAB system adopts the structure shown in  FIG. 1 . 
     As shown in  FIG. 10 , in step S 1001 , DN determines to update the time slot formats of all links in the IAB system and transmits update request information to RN 1  and UE 1 . In step S 1002 , RN 1  transmits update request information to the child nodes RN 2 , RN 3  and UE 2 . In step S 1003 , it is assumed that UE 1  has received the update request information from DN, then UE 1  transmits update response information including ACK information to DN; and it is assumed that RN 2 , RN 3 , and UE 2  have received the update request information from RN 1 , then RN 2 , RN 3 , and UE 2  transmit update response information including ACK information to RN 1 . In step S 1004 , since RN 1  has received the update response information including ACK information from all the child nodes, RN 1  transmits update response information including ACK information to DN. In step S 1005 , since DN has received ACK information from all the child nodes, DN transmits updated time slot configuration information to UE 1  and RN 1 . In step S 1006 , RN 1  transmits time slot configuration information to RN 2 , RN 3 , and UE 2 . The time slot configuration information transmitted to RN 1  includes the time slot formats of the BH 1  link, the BH 2  link, the BH 3  link and the AC 2  link. The time slot configuration information transmitted to UE 1  includes the time slot format for the AC 1  link. The time slot configuration information transmitted to RN 2  includes the time slot format for the BH 2  link. The time slot configuration information transmitted to RN 3  includes the time slot format for the BH 3  link. The time slot configuration information transmitted to UE 2  includes the time slot format for the AC 2  link. In step S 1007 , all the nodes in the IAB system update the time slot formats for related links at the update starting time. For example, DN updates the time slot formats for the links BH 1  and AC 1 , RN 1  updates the time slot formats for the BH 1  link, the BH 2  link, the BH 3  link and the AC 2  link, UE 1  updates the time slot format for the AC 1  link, and RN 2  updates the time slot format for the BH 2  link, RN 3  updates the time slot format for the BH 3  link, UE 2  updates the time slot format for the AC 2  link. Thus, the time slot formats in the IAB system are updated. 
     As shown in  FIG. 11 , in step S 1101 , DN determines to update the time slot formats of all links in the IAB system and transmits update request information to RN 1  and UE 1 . In step S 1102 , RN 1  transmits update request information to the child nodes RN 2 , RN 3  and UE 2 . In step S 1103 , it is assumed that UE 1  has received the update request information from DN, then UE 1  transmits update response information including ACK information to DN; and it is assumed that RN 2  and UE 2  have received the update request information from RN 1 , then RN 2  and UE 2  transmit update response information including ACK information to RN 1 ; and since RN 3  has not received the update request information from RN 1 , RN 3  does not transmit update response information to RN 1 . In step S 1104 , since RN 1  has not received the update response information including ACK information from all the child nodes, RN 1  transmits update response information including NACK information to DN. In step S 1105 , DN retransmits the updated time slot configuration information to RN 1 . In step S 1106 , RN 1  retransmits the updated time slot configuration information to RN 3 . In step S 1107 , it is assumed that RN 3  has received the update request information from RN 1 , then RN 3  transmits update response information to RN 1 . In step S 1108 , RN 1  transmits update response information including ACK information to DN. In step S 1109 , DN transmits updated time slot configuration information to UE 1  and RN 1 . In step S 1110 , RN 1  transmits time slot configuration information to RN 2 , RN 3 , and UE 2 . In step S 1111 , all the nodes in the IAB system update the time slot formats for related links at the update starting time. Thus, the time slot formats in the IAB system are updated. 
     As described above, according to the embodiments of the present disclosure, the DN can update the time slot formats for all the links in the IAB system, and the updated time slot formats still meet the requirements of the half-duplex mode of the IAB system. 
     According to an embodiment of the present disclosure, the RN may update a time slot format for each of part of links in the IAB system. Furthermore, the update is time-sensitive, that is, the update of the time slot format for the link by the RN is temporary. 
     According to an embodiment of the present disclosure, in a case that the electronic apparatus  200  is a RN, the electronic apparatus  200  may update the time slot format for the link between the electronic apparatus  200  and a child node of the electronic apparatus  200 , and update a time slot format for the link between the electronic apparatus  200  and a parent node of the electronic apparatus  200 . That is, the format configuration unit  220  may configure an updated time slot format of each of time slots within one time slot format cycle for a link between the electronic apparatus  100  and a child node of the electronic apparatus  100 , and the communication unit  230  may transmit updated time slot configuration information to the child node of the electronic apparatus  100 . Furthermore, the format configuration unit  220  may configure an updated time slot format of each of time slots within one time slot format cycle for a link between the electronic apparatus  100  and a parent node of the electronic apparatus  100 , and the communication unit  230  may transmit updated time slot configuration information to the parent node of the electronic apparatus  100 . 
     According to an embodiment of the present disclosure, the updated time slot configuration information may indicate information of the updated time slot format of each of the time slots within one time slot format cycle. In an embodiment, the electronic apparatus  200  may transmit the updated time slot configuration information to the child node of the electronic apparatus  200  through low layer signaling including but not limited to DCI, and transmit the updated time slot configuration information to the parent node of the electronic apparatus  200  through low layer signaling including but not limited to Uplink Control Information (UCI). 
     According to an embodiment of the present disclosure, in a case that the electronic apparatus  200  has multiple child nodes, the electronic apparatus  200  may update a time slot format of a link between the electronic apparatus  200  and each of the multiple child nodes. 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may transmit update starting time and update duration of the updated time slot format to the child node and the parent node of the electronic apparatus  200 . The update starting time may indicate the starting time for updating the time slot format, and the update starting time should be at the beginning of a time slot format cycle. Assuming that the time slot format cycle is equal to a length of a subframe, that is, 1 ms, the update starting time may indicate from which subframe the updated time slot format is adopted. The update duration may indicate the duration of the updated time slot format, and the update duration should be an integer multiple of the time slot format cycle. Assuming that the time slot format cycle is equal to a length of a subframe, that is, 1 ms, the update duration may indicate how many subframes the updated time slot format is to be used. The update starting time and the update duration may be included in the time slot configuration information, or be independent from the time slot configuration information. For example, the electronic apparatus  200  may add fields in low layer signaling to indicate the update starting time and the update duration, where the fields and values of the fields are shown in Table 10. Slotformat-change-time indicates the update starting time, and Slotformat-change-duration indicates the update duration. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 10 
               
               
                   
                   
               
               
                   
                 Field 
                 Value 
               
               
                   
                   
               
             
            
               
                   
                 Slotformat-change-time 
                 BIT STRING 
               
               
                   
                 Slotformat-change-duration 
                 BIT STRING 
               
               
                   
                   
               
            
           
         
       
     
     According to an embodiment of the present disclosure, the number of symbols for transmitting information by the electronic apparatus  200  is increased in the updated time slot format of the link between the electronic apparatus  200  and the child node of the electronic apparatus  200  and in the updated time slot format of the link between the electronic apparatus  200  and the parent node of the electronic apparatus  200 . That is, if the electronic apparatus  200  wants to increase the number of symbols for transmitting information, the electronic apparatus  200  may update the time slot format of the link between the electronic apparatus  200  and the child node of the electronic apparatus  200  and update the time slot format of the link between the electronic apparatus  200  and the parent node of the electronic apparatus  200 . The symbols for transmitting information may be UL symbols or DL symbols. For example, the electronic apparatus  200  increases the number of DL symbols of the link between the electronic apparatus  100  and the child node of the electronic apparatus  200 , and increases the number of UL symbols of the link between the electronic apparatus  100  and the parent node of the electronic apparatus  200 . 
       FIG. 12  is a signaling flow chart of updating, by a RN, a time slot format of each of part of links in an IAB system according to an embodiment of the present disclosure. As shown in  FIG. 12 , assuming that RN 1  is a parent node of RN 2 , RN 3  is a child node of RN 2 , the link between RN 2  and RN 1  is BH 1 , and the link between RN 2  and RN 3  is BH 2 . If RN 2  wants to increase the number of symbols for transmitting information, it indicates that the number of UL symbols is increased for the BH 1  link and the number of DL symbols is increased for the BH 2  link. In this case, RN 2  may configure updated time slot format for the BH 1  link and for the BH 2  link, and generate time format configuration information. Furthermore, RN 2  may transmit updated time slot configuration information for BH 1  link to RN 1 , and transmit updated time slot configuration information for BH 2  link to RN 3 . 
     According to an embodiment of the present disclosure, the electronic apparatus  200  may receive response information indicating whether to agree to update the time slot format from the child node and parent node of the electronic apparatus  200  after transmitting the updated time slot configuration information to the child node and the parent node. The format management unit  260  may, if the response information from the child node of the electronic apparatus  200  indicates that the child node agrees to update the time slot format and the response information from the parent node of the electronic apparatus  200  indicates that the parent node agrees to update the time slot format, update the time slot format at the update starting time, and restore, after the update duration, the time slot format to the time slot format before being updated. In this case, the child node and the parent node may update the time slot format at the update starting time, and restore, after the update duration, the time slot format to the time slot format before being updated. 
     According to an embodiment of the present disclosure, if the response information from the child node of the electronic apparatus  200  indicates that the child node disagrees to update the time slot format and/or the response information from the parent node of the electronic apparatus  200  indicates that the parent node disagrees to update the time slot format, the time slot format is not updated. In this case, the electronic apparatus  200  may transmit information indicating that the time slot format is not to be updated to the child node and the parent node. In an embodiment, the electronic apparatus  200  may transmit the information to the child node and the parent node through low layer signaling (including but not limited to DCI and UCI). 
     According to an embodiment of the present disclosure, the DN may add a field in the RRC signaling, where the field and a value of the field are shown in the following Table. Slotformat-changebyRN-applicable indicates whether to allow the RN to update the time slot formats of part of links in the IAB system. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 11 
               
               
                   
                   
               
               
                   
                 Field 
                 Value 
               
               
                   
                   
               
             
            
               
                   
                 Slotformat-changebyRN-applicable 
                 BOOLEAN 
               
               
                   
                   
               
            
           
         
       
     
     That is, only after the electronic apparatus  200  is configured to be allowed to update the time slot formats of part of the links in the IAB system, the electronic apparatus  200  may update the time slot format of the link between the electronic apparatus  200  and the child node and the time slot format of the link between the electronic apparatus  200  and the parent node. For example, the following codes may be added in the RRC signaling such as UL-DL-Configuration-common, UL-DL-Configuration-common-set2, and UL-DL-Configuration-dedicate: 
     
       
         
           
               
               
               
             
               
                   
                   
               
             
            
               
                   
                 TDD-UL-DL-ConfigCommon::= 
                 SEQUENCE{ 
               
            
           
           
               
               
               
            
               
                   
                 referenceSubcarrierSpacing 
                 SubcarrierSpacing 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
               
               
            
               
                   
                 dl-UL-TransmissionPeriodicity 
                 ENUMERATED 
                  {ms0p5, 
               
            
           
           
               
               
            
               
                 ms0p625, ms1, ms1p25, ms2, ms2p5, ms5, ms10} 
                  OPTIONAL, 
               
            
           
           
               
               
               
            
               
                   
                 nrofDownlinkSlots 
                 INTEGER (0..maxNrofSlots) 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
               
            
               
                   
                 nrofDownlinkSymbols 
                  INTEGER 
               
            
           
           
               
            
               
                 (0..maxNrofSymbols-1) 
               
            
           
           
               
               
               
            
               
                   
                 OPTIONAL, 
                 -- Need R 
               
            
           
           
               
               
               
            
               
                   
                 nrofUplinkSlots 
                 INTEGER (0..maxNrofSlots) 
               
            
           
           
               
               
            
               
                   
                 OPTIONAL, 
               
            
           
           
               
               
               
            
               
                   
                 nrofUplinkSymbols 
                 INTEGER 
               
            
           
           
               
               
               
            
               
                 (0..maxNrofSymbols-1) 
                 SlotformatchangebyRNapplicable 
                 BOOLEAN 
               
            
           
           
               
               
            
               
                   
                 } 
               
               
                   
                   
               
            
           
         
       
     
       FIG. 13  and  FIG. 14  are signaling flow charts of updating, by a RN, a time slot format of each of part of nodes in an IAB system according to an embodiment of the present disclosure. In  FIG. 13  and  FIG. 14 , the structure shown in  FIG. 12  is adopted, that is, RN 1  is a parent node of RN 2 , and RN 3  is a child node of RN 2 . 
     As shown in  FIG. 13 , in step S 1301 , RN 2  configures updated time slot format, update starting time, and update duration for the BH 1  link and the BH 2  link. In step S 1302 , RN 2  transmits the updated time slot format, the update starting time and the update duration for the BH 1  link to RN 1  through UCI, and transmit the updated time slot format, the update starting time and the update duration for the BH 2  link to RN 3  through DCI. In step S 1303 , RN 3  transmits response information indicating that RN 3  agrees to update the time slot format to RN 2 . In step S 1304 , RN 1  transmits response information indicating that RN 1  agrees to update the time slot format to RN 2 . In step S 1305 , RN 1 , RN 2 , and RN 3  respectively update the time slot format of the related link at the update starting time. For example, RN 1  updates the time slot format of the BH 1  link, RN 2  updates the time slot format of the BH 1  link and the BH 2  link, and RN 3  updates the time slot format of the BH 2  link. In step S 1306 , RN 1 , RN 2 , and RN 3  respectively restore the time slot format to the time slot format before being updated after the update duration. Thus, RN 2  may temporarily change the time slot format of the link between RN 2  and the child node of RN 2  and the time slot format of the link between RN 2  and the parent node of RN 2 . 
     As shown in  FIG. 14 , in step S 1401 , RN 2  configures updated time slot format, update starting time, and update duration for the BH 1  link and the BH 2  link. In step S 1402 , RN 2  transmits the updated time slot format, the update starting time and the update duration for the BH 1  link to RN 1  through UCI, and transmit the updated time slot format, the update starting time and the update duration for the BH 2  link to RN 3  through DCI. In step S 1403 , RN 3  transmits response information indicating that RN 3  agrees to update the time slot format to RN 2 . In step S 1404 , RN 1  transmits response information indicating that RN 1  disagrees to update the time slot format to RN 2 . In step S 1405 , RN 2  transmits information indicating that the time slot format is not to be updated to RN 1  through UCI, and transmits information indicating that the time slot format is not to be updated to RN 3  through DCI. In the embodiment shown in  FIG. 14 , RN 1  disagrees to update the time slot format. According to the embodiment of the present disclosure, if RN 3  disagrees to update the time slot format, or both RN 1  and RN 3  do not agree to update the time slot format, RN 2  should transmit information indicating that the time slot format is not to be updated to RN 1  and RN 3 . 
     According to the embodiments of the present disclosure, a time slot format cycle and a time slot format can be configured for a link according to a subcarrier interval of the link. To save signaling overhead, some time slot formats are defined and the way of reporting a time slot format is optimized according to the present disclosure. In addition, the DN can update the time slot formats for all links in the IAB system, and the RN can update the time slot formats for a part of links in the IAB system. In summary, the process for configuring the time slot format in the IAB system is optimized according to the embodiments of the present disclosure. 
       FIG. 15  is a block diagram showing a structure of an electronic apparatus  1500  serving as a child node in an IAB wireless communication system according to an embodiment of the present disclosure. The electronic apparatus  1500  may serve as a RN or a UE in the IAB wireless communication system. It should be noted that, since both the electronic apparatus  1500  and the electronic apparatus  200  may serve as the RN in the IAB wireless communication system, the RN may be compatible with the structures and functions of the electronic apparatus  200  and the electronic apparatus  1500 . 
     As shown in  FIG. 15 , the electronic apparatus  1500  may include a communication unit  1510  and a demodulation unit  1520 . 
     All units of the electronic apparatus  1500  may be included in processing circuitry. It should be noted that the electronic apparatus  1500  may include one or more processing circuitry. The processing circuitry may include various independent functional units to perform various different functions and/or operations. It should be noted that the functional units may be physical entities or logical entities, and units with different names may be implemented by the same physical entity. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive a time slot format cycle of a link between the electronic apparatus  1500  and a parent node of the electronic apparatus  1500  from the parent node. The time slot format cycle included a predetermined number of time slots. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive time slot configuration information from the parent node. 
     According to an embodiment of the present disclosure, the demodulation unit may demodulate the time slot configuration information to obtain the time slot format of each of time slots of the link between the electronic apparatus  1500  and the parent node within one time slot format cycle. 
     As described above, according to the embodiments of the present disclosure, the electronic apparatus  1500  may receive the time slot format cycle and the time slot format of each of the time slots within one time slot format cycle from the parent node, thereby optimizing the configuration of the time slot format in the IAB system. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive the time slot format cycle of the link between the electronic apparatus  1500  and the parent node through high layer signaling. 
     According to the embodiment of the present disclosure, the demodulation unit  1520  may demodulate the time slot configuration information to obtain identification information of the time slot format of each of the time slots within one time slot format cycle. The demodulation unit  1520  may determine the time slot format of each of the time slots according to the identification information of the time slot format of the time slot. 
     As shown in  FIG. 15 , the electronic apparatus  1500  may further include a format management unit  1540  according to an embodiment of the present disclosure. The format management unit  1540  is configured to manage the time slot format of each of the links related to the electronic apparatus  1500 . For example, the electronic apparatus  1500  may store the demodulated time slot format in the format management unit  1540 . 
     According to an embodiment of the present disclosure, the demodulation unit  1520  may demodulate the time slot configuration information to obtain identification information of each of one or more time slots in which uplink/downlink conversion occurs within one time slot format cycle, and identification information of a time slot format of the time slot. The demodulation unit  1520  may determine, according to the identification information of each of the one or more time slots in which uplink/downlink conversion occurs and the identification information of the time slot format of the time slot, a uplink/downlink type of each of symbols within one time slot format cycle. For example, it is assumed that one time slot format cycle includes four time slots. If the demodulation unit  1520  determines that there is only one time slot, a second time slot, in which uplink/downlink conversion occurs, and the time slot format of the time slot is DL, DL, DL, DL, DL, DL, UL, UL, UL, UL, UL, UL, UL, and UL, the demodulation unit  1520  may determine that a first time slot has a time slot format of all DL symbols, a third time slot has a time slot format of all UL symbols, and a fourth time slot has a time slot format of all UL symbols. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive the identification information of each of the one or more time slots in which uplink/downlink conversion occurs through high layer signaling. Further, the communication unit  1510  may receive the identification information of the time slot format of each of the one or more time slots in which uplink/downlink conversion occurs through low layer signaling. 
     As described above, some new time slot formats are defined according to the present disclosure, as shown in Table 3 and Table 7. As shown in  FIG. 15 , the electronic apparatus  1500  may further include a storage unit  1530  according to an embodiment of the present disclosure. The storage unit  1530  is configured to store a mapping relationship between the numbers of the newly defined time slot formats and the time slot formats. Thus, the demodulation unit  1520  may determine a time slot format according to the table stored in the storage unit  1530  after demodulating the number of the time slot format. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive updated time slot configuration information from a DN. The demodulation unit  1520  may determine, according to the updated time slot configuration information, an updated time slot format of each of the time slots within one time slot format cycle of the link between the electronic apparatus  1500  and the parent node of the electronic apparatus  1500  and an updated time slot format of each of time slots within one time slot format cycle of a link between the electronic apparatus  1500  and a child node of the electronic apparatus  1500  (if the electronic apparatus  1500  has a child node). That is, the demodulation unit  1520  may determine a time slot format of a link related to the electronic apparatus  1500  according to the updated time slot configuration information. The link related to the electronic apparatus  1500  includes a link with the electronic apparatus  1500  as an end, a link between the electronic apparatus  1500  and each of the child nodes, and a link between the electronic apparatus  1500  and the parent node. 
     In an embodiment, the communication unit  1510  may receive the updated time slot configuration information through low layer signaling. 
     According to an embodiment of the present disclosure, the communication unit  1510  may, before receiving the updated time slot configuration information from DN, receive update request information from DN, and the communication unit  1510  may, if the update request information has been received from DN, transmit update response information to DN. 
     According to an embodiment of the present disclosure, in a case that the electronic apparatus  1500  has no child nodes, the electronic apparatus  1500  may, after receiving the update request information, transmit update response information including ACK to the parent node of the electronic apparatus  1500 ; in a case that the electronic apparatus  1500  has child nodes, the electronic apparatus  1500  may, after receiving update response information including ACK from each of the child nodes of the electronic apparatus  1500 , transmit the update response information including ACK to the parent node of the electronic apparatus  1500 ; and in a case that the electronic apparatus  1500  has child nodes, the electronic apparatus  1500  may, after receiving update response information including NACK from one or more of the child nodes or receiving no update response information from the one or more of the child nodes, transmit the update response information including NACK to the parent node of the electronic apparatus  1500 . 
     According to an embodiment of the present disclosure, the update request information includes update starting time of the updated time slot format. The communication unit  1510  may receive the update request information through the high layer signaling. 
     According to an embodiment of the present disclosure, the format management unit  1540  may update the time slot format of each of the time slots within one time slot format cycle at the update starting time. 
     As described above, the electronic apparatus  1500  may update the time slot formats of the links related to the electronic apparatus  1500  according to the instruction from the DN. 
     According to an embodiment of the present disclosure, the communication unit  1510  may receive updated time slot configuration information from the parent node of the electronic apparatus 1500, and the demodulation unit  1520  may determine an updated time slot format of each of the time slots within one time slot format cycle of the link between the electronic apparatus  1500  and the parent node according to the updated time slot configuration information. 
     In an embodiment, the demodulation unit  1510  may demodulate the time slot configuration information to obtain update starting time and update duration of the updated time slot format. The communication unit  1510  may receive the updated time slot configuration information from the parent node of the electronic apparatus  1500  through low layer signaling. 
     As shown in  FIG. 15 , the electronic apparatus  1500  may further include a determination unit  1550  according to an embodiment of the present disclosure. The determination unit  1550  is configured to determine whether to agree to update the time slot format after the updated slot configuration information is received from the parent node. The communication unit  1510  may transmit response information indicating whether to agree to update the time slot format to the parent node of the electronic apparatus  1500 . 
     According to an embodiment of the present disclosure, if the electronic apparatus  1500  has not received information indicating that the time slot format is not to be updated from the parent node before the update starting time, the format management unit  1540  may update the time slot format of each of the time slots of the link between the electronic apparatus  1500  and the parent node within one time slot format cycle at the update starting time, and after the update duration, the format management unit  1540  may restore the time slot format to the time slot format before being updated. 
     According to an embodiment of the present disclosure, if the electronic apparatus  1500  receives information indicating that the time slot format is not to be updated from the parent node before the update starting time, the electronic apparatus  1500  does not update the time slot format. 
     According to an embodiment of the present disclosure, the number of symbols for receiving information by the electronic apparatus  1500  is increased in the updated time slot format of the link between the electronic apparatus  1500  and the parent node according to the time slot format demodulated by the demodulation unit  1520 . 
     As described above, according to the embodiments of the present disclosure, the electronic apparatus  1500  may receive updated time slot configuration information from the parent node to temporarily update the time slot format of the link between the electronic apparatus  1500  and the parent node. The electronic apparatus  1500  may receive updated time slot configuration information from the child node to temporarily update the time slot format of the link between the electronic apparatus  1500  and the child node. 
     That is, the communication unit  1510  may receive the updated time slot configuration information from the child node of the electronic apparatus  1500 , and the demodulation unit  1520  may determine the updated time slot format of each of the time slots of the link between the electronic apparatus  1500  and the child node within one time slot format cycle according to the updated time slot configuration information. In an embodiment, the demodulation unit  1510  may demodulate the time slot configuration information to obtain the update starting time and the update duration of the updated time slot format. In an embodiment, the communication unit  1510  may receive updated time slot configuration information from the child node of the electronic apparatus  1500  through low layer signaling. In an embodiment, the determining unit  1550  may be configured to determine whether to agree to update the time slot format after the updated time slot configuration information is received from the child node. The communication unit  1510  may transmit response information indicating whether to agree to update the slot format to the child node of the electronic apparatus  1500 . According to an embodiment of the present disclosure, if the electronic apparatus  1500  has not received information indicating that the time slot format is not to be updated from the child node before the update starting time, the format management unit  1540  may update the time slot format of each of the time slots of the link between the electronic apparatus  1500  and the child node within one time slot format cycle at the update starting time, and after the update duration, the format management unit  1540  may restore the time slot format to the time slot format before being updated. If the electronic apparatus  1500  has received information indicating that the time slot format is not to be updated from the child node before the update starting time, the electronic apparatus  1500  does not update the time slot format. In addition, the number of symbols received by the electronic apparatus  1500  for transmitting information is increased in the updated time slot format of the link between the electronic apparatus  1500  and the child node according to the time slot format demodulated by the demodulation unit  1520 . 
     As described above, according to the embodiments of the present disclosure, the electronic apparatus  1500  may receive a time slot format cycle and a time slot format of each of time slots within one time slot format cycle from the parent node. The electronic apparatus  1500  may update the time slot format of each of the links in the IAB system according to the instruction from the DN, may update the time slot format of the link between the electronic apparatus  1500  and the parent node of the electronic apparatus  1500  according to the instruction from the parent node, and may update the time slot format of the link between the electronic apparatus  1500  and the child node of the electronic apparatus  1500  according to the instruction from the child node. In summary, with the electronic apparatus  1500  according to the embodiments of the present disclosure, the configuration of the time slot format in the IAB system can be optimized. 
     The electronic apparatus  200  according to the embodiments of the present disclosure may serve as the parent node in the IAB system, and the electronic apparatus  1500  may serve as the child node in the IAB system, so that all the embodiments of the electronic apparatus  200  are applicable herein. 
     A wireless communication method performed by an electronic apparatus  200  serving as a parent node in an IAB wireless communication system according to an embodiment of the present disclosure is described in detail below. 
       FIG. 16  is a flow chart of a wireless communication method performed by an electronic apparatus  200  serving as a parent node in an IAB wireless communication system according to an embodiment of the present disclosure. 
     As shown in  FIG. 16 , in step S 1610 , a time slot format cycle is configured for a link between the electronic apparatus and a child node of the electronic apparatus according to a subcarrier interval of the link. The time slot format cycle includes a predetermined number of time slots. 
     In step S 1620 , a time slot format of each of the time slots within one time slot format cycle is configured for the link. 
     In an embodiment, the configuring a time slot format cycle for the link includes: causing the subcarrier interval of the link to be proportional to a number of the time slots included in the time slot format cycle. 
     In an embodiment, the configuring a time slot format cycle for the child node includes: configuring a length of the time slot format cycle of the link in time domain to be equal to a length of one subframe. 
     In an embodiment, the wireless communication method further includes: periodically transmitting the time slot format cycle of the link to the child node. 
     In an embodiment, the transmitting the time slot format cycle of the link to the child node includes: periodically transmitting the time slot format cycle of the link to the child node through high layer signaling. 
     In an embodiment, the configuring a time slot format includes: causing uplink/downlink configuration of each of symbols within the time slot format cycle of the link to be opposite to uplink/downlink configuration of a corresponding symbol within the time slot format cycle of the link between the electronic apparatus and a parent node of the electronic apparatus, or to be the same as uplink/downlink configuration of a corresponding symbol within the time slot format cycle of the link between the electronic apparatus and another child node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: transmitting time slot configuration information indicating information of the time slot format of each of the time slots within one time slot format cycle for the link to the child node. 
     In an embodiment, the time slot configuration information includes identification information of the time slot format of each of the time slots within one time slot format cycle. 
     In an embodiment, the time slot configuration information includes identification information of each of one or more time slots in which uplink/downlink conversion occurs within one time slot format cycle, and identification information of a time slot format of the time slot. 
     In an embodiment, the wireless communication method further includes: transmitting the identification information of each of the one or more time slots in which uplink/downlink conversion occurs to the child node through high layer signaling. 
     In an embodiment, the wireless communication method further includes: transmitting the identification information of the time slot format of each of the one or more time slots in which uplink/downlink conversion occurs to the child node through low layer signaling. 
     In an embodiment, the electronic apparatus is a donor node (DN). 
     In an embodiment, the wireless communication method further includes: configuring, for each of links in the IAB system, an updated time slot format of each of time slots within one time slot format cycle; and transmitting updated time slot configuration information to all other nodes in the IAB system. 
     In an embodiment, the wireless communication method further includes: transmitting update request information to all the other nodes in the IAB system; and receiving update response information from the other nodes. 
     In an embodiment, the wireless communication method further includes: retransmitting the update request information to one or more other nodes if the update response information indicates that the one or more other nodes have not received the update request information. 
     In an embodiment, the wireless communication method further includes: transmitting the updated time slot configuration information to all the other nodes in the IAB system if the update response information indicates that all the other nodes have received the update request information. 
     In an embodiment, the update request information includes update starting time of the updated time slot format. 
     In an embodiment, the wireless communication method further includes: updating the time slot format of each of the time slots within one time slot format cycle at the update starting time if the update response information indicates that all the other nodes have received the update request information. 
     In an embodiment, the wireless communication method further includes: transmitting the update request information to all the other nodes through the high layer signaling. 
     In an embodiment, the wireless communication method further includes: transmitting the updated time slot configuration information to all other nodes through the low layer signaling. 
     In an embodiment, the electronic apparatus is a relay node (RN). 
     In an embodiment, the wireless communication method further includes: configuring, for the link between the electronic apparatus and the child node of the electronic apparatus and the link between the electronic apparatus and the parent node of the electronic apparatus, an updated time slot format of each of the time slots within one time slot format cycle; and transmitting updated time slot configuration information to the child node and the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: transmitting update starting time and update duration of the updated time slot format to the child node and the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: receiving response information indicating whether to agree to update the time slot format respectively from the child node and the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: updating the time slot format at the update starting time if both the response information from the child node of the electronic apparatus indicates that the child node agrees to update the time slot format and the response information from the parent node of the electronic apparatus indicates that the parent node agrees to update the time slot format; and restoring, after the update duration, to the time slot format before being updated. 
     In an embodiment, the wireless communication method further includes: not updating the time slot format if the response information from the child node of the electronic apparatus indicates that the child node disagrees to update the time slot format and/or the response information from the parent node of the electronic apparatus indicates that the parent node disagrees to update the time slot format. 
     In an embodiment, the number of symbols transmitted by the electronic apparatus for transmitting information is increased in the updated time slot format of the link between the electronic apparatus and the child node of the electronic apparatus and in the updated time slot format of the link between the electronic apparatus and the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: transmitting updated time slot configuration information to the child node and the parent node of the electronic apparatus through the low layer signaling. 
     According to an embodiment of the present disclosure, the method may be performed by the electronic apparatus  200  according to the embodiments of the present disclosure, so all the embodiments of the electronic apparatus  200  are applicable herein. 
     A wireless communication method performed by an electronic apparatus  1500  serving as a child node in an IAB wireless communication system according to an embodiment of the present disclosure is described in detail below. 
       FIG. 17  is a flow chart of a wireless communication method performed by an electronic apparatus  1500  serving as a child node in an IAB wireless communication system according to an embodiment of the present disclosure. 
     As shown in  FIG. 17 , in step S 1710 , a time slot format cycle of a link between the electronic apparatus and a parent node of the electronic apparatus is received from the parent node. The time slot format cycle includes a predetermined number of time slots. 
     In step S 1720 , time slot configuration information is received from the parent node. 
     In step S 1730 , a time slot format of each of time slots of the link within one time slot format cycle is determined according to the time slot configuration information. 
     In an embodiment, the receiving a time slot format cycle includes: receiving the time slot format cycle of the link through high layer signaling. 
     In an embodiment, the time slot configuration information includes identification information of the time slot format of each of the time slots within one time slot format cycle. 
     In an embodiment, the time slot configuration information includes identification information of each of one or more time slots in which uplink/downlink conversion occurs within one time slot format cycle, and identification information of a time slot format of the time slot. 
     In an embodiment, the wireless communication method further includes: receiving the identification information of each of the one or more time slots in which uplink/downlink conversion occurs through high layer signaling. 
     In an embodiment, the wireless communication method further includes: receiving the identification information of the time slot format of each of the one or more time slots in which uplink/downlink conversion occurs through low layer signaling. 
     In an embodiment, the wireless communication method further includes: receiving updated time slot configuration information from a donor node DN; and determining, according to the updated time slot configuration information, an updated time slot format of each of the time slots of the link within one time slot format cycle. 
     In an embodiment, the wireless communication method further includes: receiving update request information from the DN; and transmitting update response information to the DN. 
     In an embodiment, the update request information includes update starting time of the updated time slot format. 
     In an embodiment, the wireless communication method further includes: updating the time slot format of each of the time slots within one time slot format cycle at the update starting time. 
     In an embodiment, the wireless communication method further includes: receiving the update request information through the high layer signaling. 
     In an embodiment, the wireless communication method further includes: receiving the updated time slot configuration information through the low layer signaling. 
     In an embodiment, the wireless communication method further includes: receiving updated time slot configuration information from the parent node of the electronic apparatus; and determining, according to the updated time slot configuration information, an updated time slot format of each of the time slots of the link within one time slot format cycle. 
     In an embodiment, the wireless communication method further includes: receiving update starting time and update duration of the updated time slot format from the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: transmitting response information indicating whether to agree to update the time slot format to the parent node of the electronic apparatus. 
     In an embodiment, the wireless communication method further includes: updating the time slot format of each of the time slots within one time slot format cycle at the update starting time; and restoring, after the update duration, to the time slot format before being updated. 
     In an embodiment, the wireless communication method further includes: not updating the time slot format if information indicating that the time slot format is not to be updated is received from the parent node of the electronic apparatus. 
     In an embodiment, the number of symbols received by the electronic apparatus for transmitting information is increased in the updated time slot format of the link. 
     In an embodiment, the wireless communication method further includes: receiving updated time slot configuration information from the parent node of the electronic apparatus through the low layer signaling. 
     In an embodiment, the electronic apparatus is a relay node (RN) or a user equipment (UE). 
     According to an embodiment of the present disclosure, the method may be performed by the electronic apparatus  1500  according to the embodiments of the present disclosure, so all the embodiments of the electronic apparatus  1500  are applicable herein. 
     The technology according to the present disclosure is applicable to various products. 
     The DN according to the present disclosure may be an apparatus at the network side, such as any type of Transmitting and Receiving Point (TRP) or a base station device (such as an eNB or a gNB). The RN according to the present disclosure may be an apparatus at the network side, such as a TRP or an apparatus having certain functions of a base station device, where the certain functions include but not limited to receiving data from a UE and a DN, transmitting data to a UE and a DN, and configuring certain parameters for a UE. 
     The base station device may be implemented as a macro eNB and a small eNB, or any type of gNB. The small eNB may be an eNB, such as a pico eNB, a micro eNB, and a home (femto) eNB, which covers a cell smaller than a macro cell. Alternatively, the base station may be implemented as any other type of base station, such as a NodeB and a base transceiver station (BTS). The base station may include a body (which is also referred to as a base station device) configured to control wireless communications; and one or more remote radio heads (RRHs) arranged in a different position from the body. 
     The user equipment may be implemented as a mobile terminal (such as a smart phone, a tablet personal computer (PC), a notebook PC, a portable game terminal, a portable/dongle type mobile router, and a digital camera device), or an in-vehicle terminal (such as a car navigation device). The user equipment may also be implemented as a terminal (which is also referred to as a machine type communication (MTC) terminal) that performs machine-to-machine (M2M) communication. Furthermore, the user equipment may be a wireless communication module (such as an integrated circuit module including a single die) mounted on each of the terminals. 
       FIG. 18  is a block diagram showing a first example of a schematic configuration of a gNB to which the technology of the present disclosure may be applied. A gNB  1800  includes one or more antennas  1810  and a base station device  1820 . The base station device  1820  and each of the antennas  1810  may be connected to each other via a RF cable. 
     Each of the antennas  1810  includes a single or multiple antenna elements (such as multiple antenna elements included in a multiple-input multiple-output (MIMO) antenna), and is used for transmitting and receiving wireless signals by the base station device  1820 . As shown in  FIG. 18 , the gNB  1800  may include multiple antennas  1810 . For example, the multiple antennas  1810  may be compatible with multiple frequency bands used by the gNB  1800 . Although  FIG. 18  shows the example in which the gNB  1800  includes the multiple antennas  1810 , the gNB  800  may also include a single antenna  1810 . 
     The base station device  1820  includes a controller  1821 , a memory  1822 , a network interface  1823 , and a wireless communication interface  1825 . 
     The controller  1821  may be, for example, a CPU or a DSP, and operate various functions of a higher layer of the base station device  1820 . For example, the controller  1821  generates a data packet from data in signals processed by the wireless communication interface  1825 , and transfers the generated packet via the network interface  1823 . The controller  1821  may bundle data from multiple base band processors to generate a bundled packet, and transfer the generated bundled packet. The controller  1821  may have logical functions of performing control such as radio resource control, radio bearer control, mobility management, admission control, and scheduling. The control may be performed in corporation with a gNB or a core network node in the vicinity. The memory  1822  includes a RAM and a ROM, and stores a program which is executed by the controller  1821 , and various types of control data (such as a terminal list, transmission power data, and scheduling data). 
     The network interface  1823  is a communication interface for connecting the base station device  1820  to a core network  1824 . The controller  1821  may communicate with a core network node or another gNB via the network interface  1823 . In this case, the gNB  1800  and the core network node or the other gNB may be connected to each other via a logical interface (such as an S1 interface and an X2 interface). The network interface  1823  may also be a wired communication interface or a wireless communication interface for radio backhaul. If the network interface  1823  is a wireless communication interface, the network interface  1823  may use a higher frequency band for wireless communication than a frequency band used by the wireless communication interface  1825 . 
     The wireless communication interface  1825  supports any cellular communication scheme (such as Long Term Evolution (LTE) and LTE-Advanced), and provides wireless connection to a terminal positioned in a cell of the gNB  1800  via the antenna  1810 . The wireless communication interface  1825  may typically include, for example, a baseband (BB) processor  1826  and a RF circuit  1827 . The BB processor  1826  may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/demultiplexing, and performs various types of signal processing of layers (such as L1, medium access control (MAC), radio link control (RLC), and a packet data convergence protocol (PDCP)). The BB processor  1826  may have a part or all of the above-described logical functions instead of the controller  1821 . The BB processor  1826  may be a memory which stores a communication control program, or a module that includes a processor and a related circuit configured to execute the program. Updating the programs may change functions of the BB processor  1826 . 
     The module may be a card or a blade which is inserted into a slot of the base station device  1820 . Alternatively, the module may also be a chip that is mounted on the card or the blade. In addition, the RF circuit  1827  may include, for example, a frequency mixer, a filter, and an amplifier, and transmits and receives wireless signals via the antenna  1810 . 
     As shown in  FIG. 18 , the wireless communication interface  1825  may include multiple BB processors  1826 . For example, the multiple BB processors  1826  may be compatible with multiple frequency bands used by the gNB  1800 . As shown in  FIG. 18 , the wireless communication interface  1825  may include multiple RF circuits  1827 . For example, the multiple RF circuits  1827  may be compatible with multiple antenna elements. Although  FIG. 18  shows the example in which the wireless communication interface  1825  includes the multiple BB processors  1826  and the multiple RF circuits  1827 , the wireless communication interface  1825  may also include a single BB processor  1826  or a single RF circuit  1827 . 
       FIG. 19  is a block diagram showing a second example of a schematic configuration of a gNB to which the technology according to the present disclosure may be applied. A gNB  1930  includes one or more antennas  1940 , a base station device  1950 , and a RRH  1960 . Each of the antennas  1940  and the RRH  1960  may be connected to each other via a RF cable. The base station device  1950  and the RRH  1960  may be connected to each other via a high speed line such as an optical fiber cable. 
     Each of the antennas  1940  includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the RRH  1960  to transmit and receive wireless signals. As shown in  FIG. 19 , the gNB  1930  may include multiple antennas  1940 . For example, the multiple antennas  1940  may be compatible with multiple frequency bands used by the gNB  1930 . Although  FIG. 19  shows the example in which the gNB  1930  includes the multiple antennas  1940 , the gNB  1930  may also include a single antenna  1940 . 
     The base station device  1950  includes a controller  1951 , a memory  1952 , a network interface  1953 , a wireless communication interface  1955 , and a connection interface  1957 . The controller  1951 , the memory  1952 , and the network interface  1953  are the same as the controller  1821 , the memory  1822 , and the network interface  1823  described with reference to  FIG. 18 . 
     The wireless communication interface  1955  supports any cellular communication scheme (such as LTE and LTE-Advanced), and provides wireless communication to a terminal positioned in a sector corresponding to the RRH  1960  via the RRH  1960  and the antenna  1940 . The wireless communication interface  1955  may typically include, for example, a BB processor  1956 . Other than connecting to a RF circuit  1964  of the RRH  1960  via the connection interface  1957 , the BB processor  1956  is the same as the BB processor  1826  described with reference to  FIG. 18 . As shown in  FIG. 19 , the wireless communication interface  1955  may include multiple BB processors  1956 . For example, the multiple BB processors  1956  may be compatible with multiple frequency bands used by the gNB  1930 . Although  FIG. 19  shows the example in which the wireless communication interface  1955  includes the multiple BB processors  1956 , the wireless communication interface  1955  may also include a single BB processor  1956 . 
     The connection interface  1957  is an interface for connecting the base station device  1950  (the wireless communication interface  1955 ) to the RRH  1960 . The connection interface  1957  may be a communication module for a communication of the above high-speed line, which is used for connecting the base station device  1950  (the wireless communication interface  1955 ) the RRH  1960 . 
     The RRH  1960  includes a connection interface  1961  and a wireless communication interface  1963 . 
     The connection interface  1961  is an interface for connecting the RRH  1960  (the wireless communication interface  1963 ) to the base station device  1950 . The connection interface  1961  may also be a communication module for the communication in the above high speed line. 
     The wireless communication interface  1963  transmits and receives wireless signals via the antenna  1940 . The wireless communication interface  1963  may typically include, for example, the RF circuit  1964 . The RF circuit  1964  may include, for example, a frequency mixer, a filter, and an amplifier, and transmits and receives wireless signals via the antenna  1940 . As shown in  FIG. 19 , the wireless communication interface  1963  may include multiple RF circuits  1964 . For example, the multiple RF circuits  1964  may support multiple antenna elements. Although  FIG. 19  shows the example in which the wireless communication interface  1963  includes the multiple RF circuits  1964 , the wireless communication interface  1963  may also include a single RF circuit  1964 . 
     In the gNB  1800  and the gNB  1930  respectively shown in  FIG. 18  and FIG.  19 , the cycle configuration unit  210 , the format configuration unit  220 , the generation unit  240 , the storage unit  250 , and the format management unit  260  shown in  FIG. 2  may be respectively implemented by the controller  1821  and/or the controller  1951 . At least a part of the functions may also be implemented by the controller  1821  and the controller  1951 . For example, the controller  1821  and/or and the controller  1951  may execute instructions stored in respective memory to perform the functions of time slot format cycle configuration, time slot format configuration, configuration information generation, time slot format storage, and time slot format management. 
       FIG. 20  is a block diagram showing an example of a schematic configuration of a smartphone  2000  to which the technology according to the present disclosure may be applied. The smartphone  2000  includes a processor  2001 , a memory  2002 , a storage device  2003 , an external connection interface  2004 , a camera  2006 , a sensor  2007 , a microphone  2008 , an input device  2009 , a display device  2010 , a speaker  2011 , a wireless communication interface  2012 , one or more antenna switches  2015 , one or more antennas  2016 , a bus  2017 , a battery  2018 , and an auxiliary controller  2019 . 
     The processor  2001  may be, for example, a CPU or a system on a chip (SoC), and controls functions of an application layer and another layer of the smartphone  2000 . The memory  2002  includes a RAM and a ROM, and stores programs executed by the processor  2001  and data. The storage device  2003  may include a storage medium, such as a semiconductor memory and a hard disk. The external connection interface  2004  is an interface for connecting an external device (such as a memory card and a universal serial bus (USB) device) to the smart phone  2000 . 
     The camera  2006  includes an image sensor (such as a charge coupled device (CCD) and a complementary metal oxide semiconductor (CMOS)) and generates a captured image. The sensor  2007  may include a set of sensors, such as a measurement sensor, a gyroscope sensor, a geomagnetic sensor and an acceleration sensor. The microphone  2008  converts sound inputted into the smart phone  2000  into an audio signal. The input device  2009  includes, for example, a touch sensor configured to detect touch onto a screen of the display device  2010 , a keypad, a keyboard, a button, or a switch, and receives an operation or information inputted from a user. The display device  2010  includes a screen (such as a liquid crystal display (LCD) and an organic light-emitting diode (OLED) display), and displays an output image of the smartphone  2000 . The loudspeaker  2011  converts the audio signal outputted from the smart phone  2000  into sound. 
     The wireless communication interface  2012  supports any cellular communication scheme (such as LTE and LTE-advanced), and performs wireless communication. The wireless communication interface  2012  may generally include, for example, a BB processor  2013  and a RF circuit  2014 . The BB processor  2013  may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/de-multiplexing, and perform various types of signal processing for wireless communication. In addition, the RF circuit  2014  may include, for example, a frequency mixer, a filter, and an amplifier, and transmits and receives wireless signals via an antenna  2016 . The wireless communication interface  2012  may be a one chip module having the BB processor  2013  and the RF circuit  2014  integrated thereon. As illustrated in  FIG. 20 , the wireless communication interface  2012  may include the multiple BB processors  2013  and the multiple RF circuits  2014 . Although  FIG. 20  shows the example in which the wireless communication interface  2012  includes the multiple BB processors  2013  and the multiple RF circuits  2014 , the wireless communication interface  2012  may also include a single BB processor  2013  or a single RF circuit  2014 . 
     Furthermore, in addition to a cellular communication scheme, the wireless communication interface  2012  may support another type of wireless communication scheme, such as a short-distance wireless communication scheme, a near field communication scheme, and a wireless local area network (LAN) scheme. In this case, the wireless communication interface  2012  may include the BB processor  2013  and the RF circuit  2014  for each of the wireless communication schemes. 
     Each of the antenna switches  2015  switches connection destinations of the antennas  2016  among multiple circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface  2012 . 
     Each of the antennas  2016  includes a single or multiple antenna elements (such as multiple antenna elements included in an MIMO antenna), and is used for the wireless communication interface  2012  to transmit and receive wireless signals. As shown in  FIG. 20 , the smartphone  2000  may include the multiple antennas  2016 . Although  FIG. 20  shows the example in which the smartphone  2000  includes the multiple antennas  2016 , the smartphone  2000  may also include a single antenna  2016 . 
     Furthermore, the smartphone  2000  may include the antenna  2016  for each wireless communication scheme. In this case, the antenna switch  2015  may be omitted from the configuration of the smart phone  2000 . 
     The bus  2017  connects the processor  2001 , the memory  2002 , the storage device  2003 , the external connection interface  2004 , the camera  2006 , the sensor  2007 , the microphone  2008 , the input device  2009 , the display device  2010 , the loudspeaker  2011 , the wireless communication interface  2012  and the auxiliary controller  2019  with each other. The battery  2018  supplies power for blocks in the smart phone  2000  shown in  FIG. 20  via a feeder which is indicated partially as a dashed line in  FIG. 20 . The auxiliary controller  2019 , for example, controls a minimum necessary function for operating the smart phone  2000  in a sleeping mode. 
       FIG. 21  is a block diagram showing an example of a schematic configuration of a car navigation device  2120  to which the technology according to the present disclosure may be applied. The car navigation device  2120  includes a processor  2121 , a memory  2122 , a global positioning system (GPS) module  2124 , a sensor  2125 , a data interface  2126 , a content player  2127 , a storage medium interface  2128 , an input device  2129 , a display device  2130 , a speaker  2131 , a wireless communication interface  2133 , one or more antenna switches  2136 , one or more antennas  2137 , and a battery  2138 . 
     The processor  2121  may be, for example, a CPU or a SoC, and controls the navigation function and additional functions of the car navigation device  2120 . The memory  2122  includes a RAM and a ROM, and stores programs executed by the processor  2121  and data. 
     The GPS module  2124  measures a position (such as a latitude, a longitude, and a height) of the car navigation device  2120  based on a GPS signal received from a GPS satellite. The sensor  2125  may include a group of sensors, such as, a gyroscope sensor, a geomagnetic sensor, and an air pressure sensor. The data interface  2126  is connected to, for example, an in-vehicle network  2141  via a terminal which is not shown, and acquires data generated by the vehicle (such as vehicle speed data). 
     The content player  2127  reproduces contents stored in a storage medium (such as a CD and a DVD), where the storage medium is inserted into the storage medium interface  2128 . The input device  2129  includes, for example, a touch sensor configured to detect touch on a screen of the display device  2130 , a button, or a switch, and receives an operation or information inputted from a user. The display device  2130  includes a screen, for example, an LCD display or an OLED display, and displays an image with a navigation function or the reproduced content. The loudspeaker  2131  outputs a sound with a navigation function or the reproduced content. 
     The wireless communication interface  2133  supports any cellular communication scheme (such as, LTE and LTE-Advanced), and performs wireless communication. The wireless communication interface  2133  may usually include, for example, a BB processor  2134  and a RF circuit  2135 . The BB processor  2134  may perform, for example, encoding/decoding, modulating/demodulating, and multiplexing/de-multiplexing, and performs various types of signal processing for wireless communication. In addition, the RF circuit  2135  may include, for example, a frequency mixer, a filter, and an amplifier, and transmit and receive wireless signals via the antenna  2137 . The wireless communication interface  2133  may also be a chip module on which the BB processor  2134  and the RF circuit  2135  are integrated. As shown in  FIG. 21 , the wireless communication interface 2133 may include multiple BB processors  2134  and multiple RF circuits  2135 . Although  FIG. 21  shows an example in which the wireless communication interface  2133  includes multiple BB processors  2134  and multiple RF circuits  2135 , the wireless communication interface  2133  may include a single BB processor  2134  or a single RF circuit  2135 . 
     Furthermore, in addition to a cellular communication scheme, the wireless communication interface  2133  may support another type of wireless communication scheme, such as a short-distance wireless communication scheme, a near field communication scheme, and a wireless LAN scheme. In this case, for each of the wireless communication schemes, the wireless communication interface  2133  may include a BB processor  2134  and a RF circuit  2135 . 
     Each of the antenna switches  2136  switches connection destinations of the antennas  2137  among multiple circuits (such as circuits for different wireless communication schemes) included in the wireless communication interface  2133 . 
     Each of the antennas  2137  includes one or more antenna elements (such as multiple antenna elements included in a MIMO antenna) and is used by the wireless communication interface  2133  to transmit and receive wireless signals. As shown in  FIG. 21 , the car navigation device  2120  may include multiple antennas  2137 . Although  FIG. 21  shows the example in which the car navigation device  2120  includes the multiple antennas  2137 , the car navigation device  2120  may also include a single antenna  2137 . 
     Furthermore, the car navigation device  2120  may include an antenna  2137  for each of the wireless communication schemes. In this case, the antenna switch  2136  may be omitted from the configuration of the car navigation device  2120 . 
     The battery  2138  supplies power to each of the blocks of the car navigation device  2120  shown in  FIG. 21  via feeders which are partially shown with dashed lines in  FIG. 21 . The battery  2138  accumulates power supplied from the vehicle. 
     The technology according to the present disclosure may also be implemented as an in-vehicle system (or a vehicle)  2140  including one or more blocks of the car navigation device  2120 , the in-vehicle network  2141  and a vehicle module  2142 . The vehicle module  2142  generates vehicle data (such as vehicle speed, engine speed, and fault information), and outputs the generated data to the in-vehicle network  2141 . 
     The preferred embodiments of the present disclosure have been described above with reference to the accompanying drawings, and the present disclosure is not limited thereto. Those skilled in the art can obtain various changes and modifications within the scope of the claims, and it should be understood that these changes and modifications should fall within the technical scope of the present disclosure. 
     For example, the units shown in dashed boxes in the functional block diagrams shown in the drawings indicate that the functional units are optional in the device, and each of the optional functional unit can be combined in a certain manner to perform the required functions. 
     For example, the functions included in one unit in the embodiments may be performed by separate devices. Alternatively, the multiple functions implemented by multiple units in the embodiments may be respectively performed by separate devices. In addition, each of the functions can be performed by multiple units. Such configurations are included in the technical scope of the present disclosure. 
     In this specification, the steps shown in the flow charts can be performed sequentially in time series, and can be performed in parallel or individually instead of necessarily being performed in time series. In addition, for steps performed in time series, the order can be changed appropriately. 
     Although the embodiments of the present disclosure have been described above in detail in connection with the drawings, it should be appreciated that the embodiments described above are merely illustrative rather than limitative of the present disclosure. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the spirit and scope of the present disclosure. Therefore, the scope of the present disclosure is defined merely by the appended claims and their equivalents.