Wireless communication method and device

Abstract

The invention provides a wireless communication method and device, which can save the power consumption of terminal equipment. The method comprises: a terminal device receiving first indication information sent by a center node, the first indication information being used for indicating a network device to page the terminal device.

Description

[0001] This application is a divisional application of the case with application number 202280002769.X, application date June 28, 2022, and invention name “Method and device for wireless communication”. Technical Field

[0002] The present application relates to the field of communication technology, and more specifically, to a method and device for wireless communication. Background Art

[0003] In order to improve the communication performance of terminal devices, terminal devices can be connected to central nodes, and central nodes can provide network services for terminal devices. For example, central nodes can provide wireless fidelity (WiFi) signals for terminal devices. In a communication system with a central node, how to effectively save the power consumption of terminal devices through the assistance of the central node is a problem that needs to be solved urgently. Summary of the invention

[0004] In response to the above problems, the present application provides a method and apparatus for wireless communication, which can save power consumption of terminal equipment.

[0005] In a first aspect, a wireless communication method is provided, comprising: a terminal device receives first indication information sent by a central node, wherein the first indication information is used to instruct a network device to page the terminal device.

[0006] In a second aspect, a wireless communication method is provided, comprising: a central node sends first indication information to a terminal device, wherein the first indication information is used to instruct a network device to page the terminal device.

[0007] According to a third aspect, a method for wireless communication is provided, comprising: an access network device sends second indication information to a central node, so that the central node sends first indication information to a terminal device, wherein the first indication information is used to instruct the network device to page the terminal device.

[0008] In a fourth aspect, a method for wireless communication is provided, comprising: a core network sends third indication information to a central node so that the central node sends first indication information to a terminal device, wherein the first indication information is used to instruct a network device to page the terminal device.

[0009] In a fifth aspect, a method for wireless communication is provided, comprising: a terminal device sends a request message to a central node, wherein the request message is used to request the central node to send a preamble code of the terminal device to a network device.

[0010] In a sixth aspect, a method for wireless communication is provided, comprising: a central node receives a request message sent by a terminal device, the request message being used to request the central node to send a preamble code of the terminal device to a network device; in response to the request message, the central node sends the preamble code of the terminal device to the network device.

[0011] In a seventh aspect, a wireless communication apparatus is provided, which is a terminal device, and comprises: a receiving unit, used to receive first indication information sent by a central node, wherein the first indication information is used to instruct a network device to page the terminal device.

[0012] In an eighth aspect, a wireless communication device is provided, wherein the device is a central node, and the device comprises: a sending unit, configured to send first indication information to a terminal device, wherein the first indication information is used to instruct a network device to page the terminal device.

[0013] In the ninth aspect, a wireless communication device is provided, which is an access network device, and the device includes: a sending unit, used to send second indication information to a central node so that the central node sends first indication information to a terminal device, and the first indication information is used to instruct the network device to page the terminal device.

[0014] In the tenth aspect, a wireless communication device is provided, which is a core network, and the device includes: a sending unit, used to send third indication information to a central node so that the central node sends first indication information to a terminal device, and the first indication information is used to instruct a network device to page the terminal device.

[0015] In the eleventh aspect, a wireless communication apparatus is provided, which is a terminal device, and includes: a sending unit, used to send a request message to a central node, and the request message is used to request the central node to send a preamble code of the terminal device to a network device.

[0016] In the twelfth aspect, a wireless communication device is provided, which is a central node, and the device includes: a receiving unit, used to receive a request message sent by a terminal device, the request message is used to request the central node to send a preamble code of the terminal device to a network device; a sending unit, used to respond to the request message, and the central node sends the preamble code of the terminal device to the network device.

[0017] In the thirteenth aspect, a wireless communication apparatus is provided, comprising a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to call the computer program in the memory so that the terminal device executes the method described in any one of the first to sixth aspects.

[0018] In a fourteenth aspect, a device is provided, comprising a processor, configured to call a program from a memory to execute the method described in any one of the first to sixth aspects.

[0019] In a fifteenth aspect, a chip is provided, comprising a processor for calling a program from a memory so that a device equipped with the chip executes the method described in any one of the first to sixth aspects.

[0020] In a sixteenth aspect, a computer-readable storage medium is provided, on which a program is stored, wherein the program enables a computer to execute the method described in any one of the first to sixth aspects.

[0021] In the seventeenth aspect, a computer program product is provided, comprising a program, wherein the program enables a computer to execute the method described in any one of the first to sixth aspects.

[0022] In an eighteenth aspect, a computer program is provided, wherein the computer program enables a computer to execute the method described in any one of aspects one to six.

[0023] In the embodiment of the present application, the power consumption of the terminal device can be saved by helping the terminal device to perform paging detection or send a random access preamble code through the central node. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is an example diagram of the system architecture of the communication system that can be applied to the embodiments of the present application.

[0025] Figure 2 is an example diagram of a CPE communication system.

[0026] Figure 3 It is a schematic diagram of the relative position relationship between CPE, terminal equipment, and base station.

[0027] Figure 4 The following is an example diagram of the architecture of a V2X communication system.

[0028] Figure 5 It is a schematic flowchart of the wireless communication method provided in an embodiment of the present application.

[0029] Figure 6 is a schematic flow chart of the four-step random access process.

[0030] Figure 7 is a schematic flow chart of a two-step random access process.

[0031] Figure 8 It is a schematic flowchart of another wireless communication method provided in an embodiment of the present application.

[0032] Fig. 9 It is a structural diagram of a terminal device provided in one embodiment of the present application.

[0033] Fig.10 It is a structural diagram of a central node provided in an embodiment of the present application.

[0034] Fig.11 It is a structural diagram of an access network device provided in one embodiment of the present application.

[0035] Fig.12 It is a structural diagram of the core network provided in one embodiment of the present application.

[0036] Fig.13 It is a structural diagram of a terminal device provided in another embodiment of the present application.

[0037] Fig.14 It is a structural diagram of a central node provided in another embodiment of the present application.

[0038] Fig.15 It is a schematic diagram of the structure of a communication device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0039] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0040] Figure 1 The wireless communication system 100 used in the embodiment of the present application may include a network device 110 and a terminal 120. The network device 110 may be a device that communicates with the terminal 120. The network device 110 may provide communication coverage for a specific geographical area and may communicate with the terminal 120 located in the coverage area.

[0041] Figure 1 One network device and two terminals are shown exemplarily. Optionally, the wireless communication system 100 may include multiple network devices and each network device may include another number of terminals within its coverage area, which is not limited in the embodiments of the present application.

[0042] Optionally, the wireless communication system 100 may also include other network entities such as a network controller and a mobility management entity, which is not limited in the embodiments of the present application.

[0043] It should be understood that the technical solutions of the embodiments of the present application can be applied to various communication systems, such as: the fifth generation (5th generation, 5G) system or new radio (new radio, NR), long term evolution (long term evolution, LTE) system, LTE frequency division duplex (frequency division duplex, FDD) system, LTE time division duplex (time division duplex, TDD), etc. The technical solutions provided by the present application can also be applied to future communication systems, such as the sixth generation mobile communication system, satellite communication system, and so on.

[0044] The terminal in the embodiment of the present application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal in the embodiment of the present application may be a device that provides voice and / or data connectivity to a user, and may be used to connect people, objects and machines, such as a handheld device with wireless connection function, a vehicle-mounted device, etc. The terminal in the embodiment of the present application can be a mobile phone, a tablet computer, a laptop, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in smart grid, a wireless terminal in transportation safety, a wireless terminal in smart city, a wireless terminal in smart home, etc. Optionally, the UE can be used to act as a base station. For example, the UE can act as a scheduling entity that provides sidelink signals between UEs in V2X or D2D, etc. For example, a cellular phone and a car communicate with each other using a sidelink signal. Cellular phones and smart home devices communicate without relaying communication signals through a base station.

[0045] The network device in the embodiment of the present application may be a device for communicating with a terminal, and the network device may also be referred to as an access network device or a wireless access network device, such as a base station. The network device in the embodiment of the present application may refer to a wireless access network (RAN) node (or device) that connects a terminal to a wireless network. The base station can broadly cover various names as follows, or be replaced with the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, access point, transmission point (TRP), transmission point (TP), master station MeNB, secondary station SeNB, multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, base band unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. The base station can be a macro base station, a micro base station, a relay node, a donor node or the like, or a combination thereof. The base station may also refer to a communication module, modem or chip used to be set in the aforementioned device or apparatus. The base station may also be a mobile switching center and a device to device D2D, vehicle-to-everything (V2X), machine-to-machine (M2M) communication device that performs the base station function, a network side device in a 6G network, and a device that performs the base station function in a future communication system. The base station may support networks with the same or different access technologies. The embodiments of the present application do not limit the specific technology and specific device form adopted by the network equipment.

[0046] Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move based on the location of the mobile base station. In other examples, a helicopter or drone can be configured to act as a device that communicates with another base station.

[0047] In some deployments, the network device in the embodiments of the present application may refer to a CU or a DU, or the network device includes a CU and a DU. The gNB may also include an AAU.

[0048] The network equipment and terminals can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on the water surface; they can also be deployed on aircraft, balloons and satellites in the air. The embodiments of the present application do not limit the scenarios in which the network equipment and terminals are located.

[0049] It should be understood that all or part of the functions of the communication device in the present application may also be implemented by software functions running on hardware, or by virtualization functions instantiated on a platform (eg, a cloud platform).

[0050] In order to improve the communication performance of the terminal device, the terminal device can be connected to the central node, and the central node can provide network services for the terminal device. For example, the central node can provide WiFi signals for the terminal device. The terminal device can communicate with the network device using WiFi. Of course, in some embodiments, the central node can also provide wired network services for the terminal device. The central node in the embodiment of the present application can be a customer premise equipment (CPE), a WiFi base station, a road side unit (RSU) in a side communication system, a central node in a side communication system, etc.

[0051] The WiFi base station in the embodiment of the present application can provide WiFi signals for the terminal device. The WiFi base station can have the ability to perform uplink synchronization and / or downlink synchronization with the network device. The downlink synchronization capability may include obtaining the cell ID or physical cell identities (PCI / PCID) of the access cell, or obtaining the cell ID or PCI / PCID of the cell with the largest received power. The uplink synchronization capability may include obtaining the TA sent by the base station.

[0052] The RSU and / or central node in the sidewalk communication system is responsible for the management of the communication network in the cell and the transmission of signaling. The RSU can send data such as traffic lights, traffic signs and obstacles on the road to the vehicle. The central node can refer to the terminal in the vehicle.

[0053] Combine the following Figure 2 and Figure 3 , the CPE system in the embodiment of the present application is introduced.

[0054] CPE System

[0055] CPE is a mobile signal access device that receives mobile signals from the network side and forwards them as wireless WiFi signals. It can convert high-speed mobile signals from the network side (such as 4G signals, 5G signals, or 6G signals) into WiFi signals to communicate with the terminal, that is, to achieve the connection between the terminal and the network side through WiFi signals. CPE can be widely used in wireless network access in rural areas, towns, hospitals, units, factories, communities, etc., which can save the cost of laying wired networks.

[0056] CPE can be used to relay the operator's network signal for a second time. Figure 3 As shown, CPE 130 can receive mobile signals sent by base station 110 and convert the mobile signals into WiFi signals. For network devices, CPE is a terminal device, and a subscriber identity module (SIM) card can be inserted into CPE. Since CPE antenna gain is stronger and power is higher, its signal receiving and sending capability is stronger than that of terminal devices. Therefore, it may have a signal in some places where terminal devices have no signal. In addition, CPE can be used as a mobile relay to ensure that the terminal device has a good connection during movement.

[0057] The terminal device in the embodiment of the present application is within the coverage of both the base station and the CPE. The relative position relationship between CPE130, terminal device 120, and base station 110 can be various, and the embodiment of the present application does not specifically limit this. For example, the terminal device can be located on the line connecting the CPE and the base station, such as Figure 4 For another example, the terminal device may be located on an extension line of a line connecting the CPE and the base station, such as Figure 4 The terminal device 120A (or the terminal device 120B), the CPE, and the base station are located on a straight line. For another example, a triangle is formed between the terminal device, the CPE, and the base station, such as Figure 4 Terminal devices 120C and 120D in.

[0058] Terminal devices within the coverage of CPE can obtain the network based on the WiFi signal sent by CPE, so as to communicate with other devices. In the current CPE system, from the perspective of network devices, CPE is a terminal. For terminal devices under CPE coverage, CPE is equivalent to a WiFi base station. From the perspective of wireless communication, CPE and terminal devices are both terminals, and both communicate with network devices independently, such as downlink synchronization, reading broadcast information, uplink random access, paging, etc.

[0059] Combine the following Figure 4 , the V2X system of an embodiment of the present application is introduced.

[0060] V2X System

[0061] In the V2X system, terminals can communicate with each other through sidelink (SL). Sidelink communication can also be called proximity services (ProSe) communication, unilateral communication, sidelink communication, and device to device (D2D) communication.

[0062] In other words, sidelink data is transmitted between terminals via a sidelink. The sidelink data may include data and / or control signaling. In some implementations, the sidelink data may be, for example, a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), a PSCCH demodulation reference signal (DMRS), a PSSCH DMRS, a physical sidelink feedback channel (PSFCH), etc.

[0063] The V2X system is one of the supporting technologies for smart cars and smart transportation. The V2X system can include one or more of the following communication application scenarios: vehicle to vehicle (V2V) communication, vehicle to infrastructure (V2I) communication, vehicle to pedestrian (V2P) communication, vehicle to network (V2N) communication, etc.

[0064] Based on V2V communication, vehicles can realize forward collision warning, lane change assistance, left turn assistance, cooperative adaptive cruise control, etc. Based on V2I communication, applications such as speed suggestions, traffic priority, road condition warning, red light warning, current weather impact warning, parking space and charging pile location can be realized. Based on V2P communication, services such as warning and protection of vulnerable road users can be realized. Based on V2N communication, services such as real-time traffic route planning and map updates can be realized.

[0065] The V2X system supports centralized network models, distributed network models, and hybrid network models. The centralized network model continues the traditional communication network model, such as Figure 4As shown. The vehicle nodes communicate with each other through the central node 410 (such as a roadside unit (RSU or base station)). RSU can send data such as traffic lights, traffic signs and obstacles on the road to the vehicle. The central node is responsible for the management of the communication network in the cell and the uploading and issuing of signals. The advantage of this is that the vehicle nodes can easily access the network at any time and can connect with vehicle nodes in far away places (similar to the principle of mobile phone communication). In addition, due to the effective scheduling of the central node, the communication quality can be effectively guaranteed.

[0066] In the distributed network model, vehicles flexibly form a network in a self-organized form. The distributed network model structure can be shown in the figure. In the distributed network structure, vehicles can join or leave the network at any time without affecting the overall performance of the network. In terms of communication performance, the distributed network architecture can more effectively utilize network bandwidth.

[0067] The hybrid network model can be understood as including RSU or base station as the central node of the region for unified regulation, while allowing D2D connection between vehicles. It is compatible with the advantages of centralized network model and distributed network model, and can reduce the cost of network deployment.

[0068] In the centralized network model and the hybrid network model, if the central node is an RSU, the vehicle can establish a connection with the RSU. The RSU and the vehicle can communicate via wireless signals. The wireless signal can be a WiFi signal or a mobile signal. If there is a WiFi connection between the vehicle and the RSU, the vehicle can turn off the mobile data and communicate with the network side via WiFi.

[0069] Paging

[0070] For a terminal in the idle state of radio resource control (RRC), a paging message is usually received in a manner similar to the discontinuous reception (DRX) mechanism. There is a paging occasion (PO) in a DRX cycle. The terminal only receives paging messages during the PO period, and does not receive paging messages outside the paging occasion to save power. In addition, during the PO period, the terminal can determine whether there is a paging message by detecting the physical downlink control channel (PDCCH) scrambled with the paging radio network temporary identifier (P-RNTI).

[0071] For a terminal device in the RRC idle state, if the network device wants to send a downlink message or downlink data to the terminal device, the network device can switch the terminal device to the RRC connected state by paging. The paging process can be used to send a paging request to a terminal in the RRC idle state, or the paging process can also be used to notify the terminal of system information updates, or the paging process can also notify the terminal to receive alarm information sent by the earthquake and tsunami warning system (ETWS) and the commercial mobile alert system (CMAS).

[0072] The paging process can be triggered by the core network or the base station. The core network can be, for example, an access and mobility management function (AMF). If the paging message is initiated by the core network, the core network will send a paging message to all base stations in the tracking area (TA) registered by the terminal. After receiving the paging message sent by the core network, the base station will interpret the content, obtain a list of tracking area identities (TAI) of the paged terminal, and perform air interface paging in the cells of the tracking areas in the list. Usually, in order to save the overhead of transmitting paging messages, after receiving the paging message sent by the core network, the base station can aggregate the paging messages corresponding to the terminals with the same PO into one paging message, and finally transmit it to the relevant terminals through the paging channel. After receiving the paging message, the terminal in the RRC idle state can initiate the RRC connection establishment process to receive data or signaling.

[0073] The above-mentioned paging message is carried by the physical downlink shared channel (PDSCH). Before receiving the paging message, the terminal needs to first receive the paging parameters through the system message, and calculate the frame number and PO of the paging frame (paging frame, PF) where the paging message is located in combination with the respective UE_ID. Then, the terminal listens to the PDCCH encrypted by P-RNTI within the PO on the PF to receive the paging indication information, and finally receives the paging message based on the paging indication information. It can be understood that the paging indication information is carried in the PDCCH, and the paging message can be used to indicate the resource location of the PDSCH carrying the paging message.

[0074] For example, the terminal can detect the PDCCH in the PO to obtain the downlink control information format (downlink control information, DCI), and the cyclic redundancy check (cyclic redundancy check, CRC) of the DCI is scrambled by the P-RNTI. If the terminal device detects the DCI, the PDSCH can be received at the resource location indicated by the DCI (such as the time domain resource location and / or the frequency domain resource location). The terminal device can use a temporary mobile subscriber identity (temporary mobile subscriber identity, TMSI) (such as 5G-S-TMSI) to decode the PDSCH. If the decoding is successful, it means that the terminal device is paged and the terminal obtains the paging message from the PDSCH; if the decoding fails, it means that the terminal device is not paged.

[0075] In addition, in some communication systems (such as NR systems), for terminals in the RRC idle state, the network device does not know which transmission beam to use to send paging messages to the terminal. In order to ensure that the terminal can receive the paging message, the network device uses beam scanning to send the paging message. In order to support multi-beam transmission of paging messages, PO can be defined as a set of PDCCH monitoring occasions (PDCCH monitoring occasions), and different PDCCH monitoring occasions correspond to paging indication information sent through different transmission beams. A PF can include one or more POs or the starting time point of PO.

[0076] Since each synchronization signal block (SSB) index corresponds to a PDCCH monitoring occasions, and different SSB indices correspond to different beams, multiple PDCCH monitoring occasions in a PO can be associated with transmission beams corresponding to different SSB indices to support multi-beam transmission of paging messages. The messages sent on each SSB beam are exactly the same. Usually, the SSBs required to complete a beam scan constitute an "SSB burst". PDCCH monitoring occasions are a series of time domain locations determined by the paging search space.

[0077] Based on the above introduction, it can be known that the terminal will use a method similar to the DRX mechanism for paging detection. With the paging cycle as the period, the terminal will periodically monitor the PDCCH in the PO to obtain the paging indication information. However, for some terminals, they may not be paged for a long period of time, but they still need to be awakened periodically to monitor the PDCCH that may carry the paging indication information. There is room for further optimization of the energy-saving method of such terminals.

[0078] In order to further optimize the energy saving mode of the terminal, a scheme based on paging early indication (PEI) to further save terminal energy is discussed. In this scheme, the network device sends PEI to the terminal, and the PEI can be sent before the arrival of PO in each paging cycle, or it can be sent once in multiple paging cycles, or it can be sent multiple times in one paging cycle. The PEI can be used to indicate whether the terminal receives the PDCCH carrying paging indication information, or the PEI can be used to indicate whether the terminal receives the paging indication information, or the PEI can be used to indicate whether the terminal is awakened. The terminal will only be awakened when the PEI indicates that the terminal needs to receive the paging indication information. Otherwise, if the PEI indicates that the terminal does not need to receive the paging indication information, the terminal will remain in sleep mode to save energy.

[0079] When there is a connection link between the terminal device and the central node, the terminal device usually turns off the communication module (hereinafter referred to as the mobile communication module) that communicates with the base station (or access network device). The mobile communication module can be, for example, an LTE module or an NR module. For example, when the mobile signal and WiFi signal coexist in the terminal device, the terminal device will turn off the data service of the mobile signal, that is, the terminal device can disconnect from the base station. The data of the terminal device reaches the terminal device through the core network and WiFi. When there is a WiFi connection, the mobile communication module in the terminal device only needs to support voice services.

[0080] When there is a connection link between the terminal device and the central node, if a message from the terminal device arrives, the network device can send a paging message to the terminal device. The paging message can be triggered by one or more of the following events: a change in the system message, an early warning signal, or the arrival of a voice service from the terminal device.

[0081] Taking paging for voice services as an example, in order to support voice services, the terminal device needs to perform paging detection at a certain period. Taking the LTE communication protocol as an example, the maximum paging cycle is 2.56s, that is, the terminal device needs to wake up every 2.56s to perform paging detection. Before paging detection, the terminal device may have uplink and downlink synchronization, at which time the terminal device also needs to perform uplink and downlink synchronization. When the terminal device performs uplink and downlink synchronization, it will consume a lot of power.

[0082] In addition, in recent years, with the popularity of communication applications (applications, APPs) such as WeChat, Teams, and Skype, their communication costs are much lower than the operator's voice services, which greatly reduces the frequency of use of the operator's voice services. Although there are few voice services, the terminal device still needs to wake up according to the cycle described above for paging detection. When the WiFi module and mobile communication module of the terminal are turned on at the same time, the mobile communication module of the terminal device needs to wake up for paging detection at least every 2.56s in order to support the extremely low frequency voice service, which brings unnecessary power consumption to the terminal device.

[0083] In order to solve the above problem, the embodiment of the present application can detect the paging message of the terminal device through the central node, and notify the terminal device only when it is detected that the terminal device is paged, thereby avoiding the terminal device from waking up frequently for paging detection, which is conducive to saving the power consumption of the terminal device. Since the central node itself is also a terminal device, the central node can use its own ability to connect to the network device to assist the terminal device in paging detection, thereby achieving the purpose of energy saving.

[0084] Combine the following Figure 5 , the scheme of the embodiment of the present application is introduced.

[0085] See also Figure 5 In step S510, the central node sends first indication information to the terminal device. The first indication information is used to instruct the network device to page the terminal device.

[0086] The terminal device in the embodiment of the present application may be a terminal device in the RRC_IDLE state, or a terminal device that has not yet accessed the network, or there is no RRC connection between the terminal device and the access network device.

[0087] In the present application, the communication signal between the central node and the terminal device is a non-mobile signal. Mobile signals may refer to network signals provided by operators, and non-mobile signals may refer to network signals provided by non-operators. Mobile signals may be, for example, LTE signals, NR signals, or 6G signals, etc. Non-mobile signals may refer to, for example, WiFi signals, or wired network signals. There is a WiFi connection between the central node and the terminal device, or there is a wired connection between the central node and the terminal device. The central node may provide WiFi or wired network services to the terminal device. The central node may be one or more of the CPE described above, a WiFi base station, a roadside unit in the side communication system, or a central node in the side communication system.

[0088] The WiFi base station in the embodiment of the present application can provide a WiFi signal for the terminal device. The WiFi base station may have the ability to perform uplink synchronization and / or downlink synchronization with the network device. The downlink synchronization capability may include obtaining the cell ID or PCI / PCID of the access cell, or obtaining the cell ID or PCI / PCID of the cell with the largest receiving power, or obtaining the cell ID or PCI / PCID of several cells with the best receiving power. The uplink synchronization capability may include obtaining the TA sent by the base station.

[0089] When the central node detects that the terminal device is paged by the network device, the central node may send the first indication information to the terminal device to indicate that the terminal device is paged by the network device. The network device in the embodiment of the present application may be an access network device or a core network. In other words, the paging of the terminal device may be triggered by the access device or by the core network. The access network device in the embodiment of the present application may be a base station.

[0090] The central node may detect the message from the access network device to determine whether the terminal device is paged. Alternatively, the central node may detect the message from the core network to determine whether the terminal device is paged. Alternatively, the central node may forward the paging message or voice communication data from the core network to the terminal device. In some embodiments, the sending of the first indication information may be triggered by one or more of the following events: the central node receives the second indication information sent by the access network device, the second indication information is used to instruct the network device to page the terminal device; the central node receives the third indication information sent by the core network, the third indication information is used to instruct the network device to page the terminal device.

[0091] In some embodiments, in order to ensure that the core network or access network device can send the paging indication of the terminal device to the appropriate CPE, the core network or access network device can obtain the terminal device information within the coverage of the CPE. The information of the terminal device within the coverage of the CPE can be reported by the CPE to the network device, or by the terminal device to the access network device. For example, the CPE can report the ID information of all terminal devices within its coverage to the access network device. For another example, the terminal device can report the CPE information where it is located to the access network device.

[0092] In some embodiments, Figure 5 As shown, Figure 5 The method shown may also include step S504. In step S504, the access network device may send second indication information to the central node, so that the central node sends the first indication information to the terminal device. After receiving the second indication information, the central node may determine that the terminal device is paged. Further, in response to the second indication information, the central node sends the first indication information to the terminal device.

[0093] In some embodiments, the second indication information may be carried by the PEI of the terminal device, and the PEI indicates that the terminal device needs to receive paging indication information (or paging message). The central node may receive the PEI for the terminal device sent by the access network device. If the PEI indicates that the terminal device needs to receive paging indication information, the central node may send the first indication information to the terminal device. If the PEI indicates that the terminal device does not need to receive paging indication information, the central node may not send the first indication information to the terminal device.

[0094] In some embodiments, the PEIs of all terminal devices covered by the central node are carried in the same control information. The serial number of the PEI of the terminal device in all PEI bits corresponding to the central node can be determined based on the first information. The first information may include one or more of the following information: the serial number of the terminal device in all terminal devices covered by the central node, the number of bits of the PEI corresponding to the central node, and the bit serial number of the PEI of the first terminal device in the PEI bit corresponding to the central node.

[0095] In some embodiments, the number of bits of the PEI corresponding to the central node is small, which is not enough to allocate a dedicated PEI to each terminal device. In this case, multiple terminal devices can share one PEI, that is, the one PEI can be used to indicate whether the multiple terminal devices receive paging indication information. The PEI corresponding to the central node can be understood as the PEI occupied by all terminal devices covered by the central node, or it can be understood as the PEI occupied by the central node and all terminal devices covered by the central node.

[0096] The first terminal device can be understood as the terminal device with the first serial number among all the terminal devices covered by the central node. The bit serial number of the PEI of the first terminal device in the PEI bit corresponding to the central node can also be called the starting bit serial number. Assuming that the PEI bit corresponding to the central node is bit 0 to bit 20, the starting bit serial number can be any one of 0 to 20. In other words, the central node or network device can configure the PEI bit for the terminal device starting from bit 0, or it can configure the PEI bit for the terminal device starting from other bit positions.

[0097] When configuring PEI bits for terminal devices, the central node or network device may configure PEI bits for the terminal devices according to the sequence of the terminal device identifiers (or serial numbers). For example, the central node may sort the terminal device identifiers from large to small or from small to large, and allocate PEI bits to the terminal devices in sequence.

[0098] In some embodiments, the PEI of the terminal device is the serial number i among all PEI bits corresponding to the central node. PEI Determined according to the following formula:

[0099] i PEI =mod(n intraUEID ,N)+i begin

[0100] Where N is the number of PEI bits corresponding to the central node, i begin is the bit number of the PEI of the first terminal device in the PEI bit corresponding to the central node, n intraUEID It is the serial number of the terminal device among all the terminal devices covered by the central node.

[0101] The value of N can be notified to the central node by the base station. begin The value can be notified to the central node by the base station, or the central node can calculate it according to the existing protocol based on the UE ID of the central node. intraUEID The value is notified to the base station.

[0102] Of course, in some embodiments, the PEI of each terminal may also be indicated in accordance with existing standard methods. The central node detects the PEI of each terminal, and if the corresponding PEI is detected, the central node notifies the terminal that it needs to wake up to detect paging messages or receive communication data.

[0103] When configuring the PEI of the terminal device, the access network device can notify the central node of the PEI corresponding to each terminal device. Taking the CPE system as an example, the access network device can notify the CPE of the PEI corresponding to all terminal devices within the coverage of the CPE. In some embodiments, the PEI can indicate whether a terminal device needs to receive paging indication information, or the PEI can indicate whether a group of terminal devices need to receive paging indication information. In other words, one PEI can correspond to one terminal device or a group of terminal devices.

[0104] In order to reduce the complexity of PEI detection, the PEI of the terminal device can be carried in one control information with the PEI of other devices. The control information can be PDCCH or DCI. For example, the PEI of the terminal device is carried in the first control information, and the first control information can also include one or more of the following information: the PEI of the central node, the PEI of other terminal devices. Other terminal devices can be devices connected to the central node, or in other words, other terminal devices can be other terminal devices within the coverage of the central node. In this way, the central node can detect the PEI of the central node and other devices by receiving a control information, thereby reducing the complexity of PEI detection. PDCCH or DCI is a signaling of the physical layer, which indicates whether the terminal is paging through physical layer signaling, and has a lower delay.

[0105] In some embodiments, the second indication information is carried in a paging message of the central node. The central node can perform a detection on its own paging opportunity to determine whether the terminal device is paged.

[0106] The second indication information may be carried in the paging PDSCH of the central node. The paging PDSCH may refer to the PDSCH scheduled by the PDCCH on the paging opportunity of the central node, and the PDSCH is used to carry the paging message of the central node. For example, the central node may receive the PDCCH on the paging opportunity of the central node, and receive the paging message on the PDSCH scheduled by the PDCCH. The PDSCH contains indication information of whether the terminal device is paged. If the PDSCH contains indication information that the terminal device is paged, that is, contains the second indication information, the central node sends the first indication information to the terminal device. If the PDSCH does not contain indication information that the terminal device is paged, the central node does not send the first indication information to the terminal device.

[0107] In some embodiments, the second indication information is indicated by an identifier of the terminal device. For example, if the paging message of the central node includes the identifier of the terminal device, it indicates that the terminal device is paged. If the paging message of the central node does not include the identifier of the terminal device, it indicates that the terminal device is not paged.

[0108] The identification of the terminal device may be the ID of the terminal device. Alternatively, the identification of the terminal device may be the serial number of the terminal device among the terminal devices covered by the central node. Since the number of terminal devices covered by the central node is relatively small compared to the terminal devices covered by the base station, the serial number of the terminal device among the terminal devices covered by the central node may be used as the identification information to save signaling load.

[0109] The identification information of the terminal device can be reported by the central node to the base station, or the identification information of the terminal device can be determined by the base station itself. For example, the central node can number the terminal devices within its coverage area and report the numbering information of the terminal devices to the base station. For another example, the base station and the central node can sort the IDs of the terminal devices based on the same sorting method to determine the number of the terminal devices. The sorting method can be negotiated by the base station and the central node, or notified by the base station to the central node, or notified by the central node to the base station.

[0110] In some embodiments, the second indication information may be obtained by the central node through paging detection based on the paging configuration information of the terminal device. For example, the central node may detect at the paging opportunity of the terminal device based on the paging configuration information of the terminal device to determine whether the terminal device is paged. If it is detected that the terminal device is paged, the central node sends the first indication information to the terminal device. If it is not detected that the terminal device is paged, the central node may not send the first indication information to the terminal device.

[0111] The paging opportunity of the terminal device may be determined by the paging configuration parameters of the terminal device. The paging configuration parameters may be sent by the base station to the central node, or may be sent by the terminal device to the central node. The paging configuration parameters may include one or more of the following information: a search space of the PDCCH, a paging cycle, a paging opportunity, and an ID of the terminal device. The central node may determine the paging opportunity of the terminal device based on the paging configuration parameters of the terminal device.

[0112] This solution does not change the base station side, and the base station can page the terminal device in the original way of sending paging messages.

[0113] In some embodiments, Figure 5 As shown, Figure 5 The method shown may further include step S502. In step S502, the core network may send third indication information to the central node to indicate that the terminal device is paged. By sending indication information to the central node through the core network, changes to the network side may be reduced, and implementation complexity is low.

[0114] In order to enable the message sent by the core network to reach the terminal device, the third indication information may also include one or more of the following information: an Internet Protocol (IP) address of the terminal device, an IP address of the central node, an identifier of the terminal device, and an identifier of the central node. The IP address of the central node or the identifier of the central node may be used to send the second indication information to the central node. The IP address of the terminal device or the identifier of the terminal device may be used by the central node to transmit the first indication information to the terminal device.

[0115] Taking paging for voice calls as an example, the maintenance of the IP address can be done by the called operator, the calling operator, or a third party organization.

[0116] The embodiment of the present application does not specifically limit the manner in which the central node sends the first indication information to the terminal device. For example, the central node may send the first indication information via a WiFi signal and / or a WiFi sequence. The WiFi sequence may be, for example, a WiFi beacon. The WiFi signal may be a WiFi pilot signal.

[0117] In some embodiments, the first indication information may be received by a wake-up device in the terminal device. The central node may send the first indication information to the wake-up device in the terminal device. After receiving the first indication information, the wake-up device may wake up the terminal device. Receiving the first indication information through hardware has a lower transmission delay, thereby ensuring the transmission delay of the data. In addition, the power consumption of the wake-up device is extremely low (at the nanowatt level), and the receiving sensitivity can reach tens of meters. Therefore, using the wake-up device to receive the first indication information will not have a significant impact on the power consumption of the terminal device.

[0118] The greater the power consumption of the wake-up device, the higher the receiving sensitivity and the longer the distance supported for transmission and reception. The power consumption of the wake-up device will vary depending on the coverage range of the central node. Since the base station is far away from the terminal device, if the wake-up device detects the paging indication information sent by the base station, the required power consumption is relatively large. Since the central node is close to the terminal device, the terminal device can use a wake-up device with lower power consumption to receive the first indication information sent by the central node.

[0119] The wake-up device in the terminal device can periodically detect the signal sent by the central node.

[0120] The central node may send the first indication information in the form of a sequence. When there are multiple terminal devices within the coverage of the central node, the central node may configure a sequence for each terminal device in advance. When a terminal device is paged, the central node may send a sequence corresponding to the terminal device. The wake-up device of the terminal device may match the received sequence, and if the match is successful (such as the value after the match is greater than a preset threshold), the terminal device is considered to be paged. If the match is unsuccessful, it can be considered that the terminal device has not been paged.

[0121] Specifically, the control module of the wake-up device in the terminal device can receive the sequence code assigned by the central node to the terminal device. The terminal device configures the sequence code for the control module. The terminal device can use the sequence code for detection. For example, the terminal device can use a matching correlation algorithm to match the received sequence code and the local sequence code to determine the detection result. The terminal device determines whether the terminal device is paged based on the detection result. For example, if the detection result is greater than a preset threshold, the terminal device can determine that it is paged. If the detection result is less than or equal to the preset threshold, the terminal device can determine that it is not paged.

[0122] After receiving the first indication information, the terminal device may receive the paging message. The embodiment of the present application does not specifically limit the receiving method of the paging message. For example, the terminal device may receive the paging message through the central node. For another example, the terminal device may receive the paging message through the access network device.

[0123] If the terminal device receives a paging message through the access network device, the terminal device is awakened after receiving the first indication information, and the terminal device can wake up to receive or detect the paging message. Since the terminal device wakes up to receive the paging message only after determining that it is paged, rather than waking up periodically for paging detection, the power consumption of the terminal device can be saved. In some embodiments, the terminal device can turn on the mobile communication module and establish a connection with the access network device to receive the paging message sent by the access network device. Receiving the paging message through the access network device can ensure the security of the data. For example, the terminal device can detect the PDCCH on its own paging opportunity, and then detect the paging message on the PDSCH scheduled by the PDCCH, thereby completing the reception of the paging message. Before receiving the paging message, the terminal device needs to establish a connection with the access network device. For example, the terminal device can complete uplink and downlink synchronization, random access, signal measurement, etc. with the access network device.

[0124] If the first indication information is received by the wake-up device, the wake-up device may wake up the mobile communication module of the terminal device after receiving the first indication information, that is, turn on the mobile communication module of the terminal device. The wake-up device and the mobile communication module may be electrically connected. For example, after receiving the first indication information, the wake-up device may output a high level to trigger the mobile communication module to turn on.

[0125] If the terminal device receives the paging message through the central node, the terminal device can keep the mobile communication module in the off state and receive the paging message through the WiFi signal between the central node. Receiving the paging message through the central node can save the communication fee of the terminal device and reduce the communication cost.

[0126] In some embodiments, a network device (such as an access network device or a core network) can send a paging message to a central node, which then transmits the paging message to the terminal device. In some embodiments, the central node can transmit the paging message to the terminal device by transparent transmission. In this case, the central node does not need to process the paging message, and the security of the terminal device data can be guaranteed. Of course, in some embodiments, the central node can convert the format of the paging message into data that can be recognized by the terminal device, for example, into an APP data packet.

[0127] If the paging message is sent through the core network (i.e., the core network directly sends it to the central node without passing through the access network device), in order to ensure that the terminal device can correctly receive the paging message, the core network or the central node can convert the paging message into a data packet that the terminal device can recognize, for example, the paging message can be converted into an APP data packet. The core network performs data format conversion to ensure the security of data transmission, and the central node only needs to transparently transmit the data packet sent by the core network to the terminal device.

[0128] The APP can be an APP dedicated to receiving paging messages, or the APP can reuse an existing APP to receive paging messages. Reusing an existing APP can further save the power consumption of the terminal device. In addition, receiving paging messages in the form of APP data packets can also avoid blind detection of the terminal device on the paging opportunity, which can reduce the detection power consumption of the terminal device.

[0129] In the embodiment of the present application, the paging cycle of the central node can be smaller than the paging cycle of the terminal device, so that the central node can obtain the information of whether the terminal device is paged earlier, avoiding increasing the paging delay of the terminal device. Since the central node (such as CPE) is large in size and usually works in an active state or has a large battery capacity, the CPE can support a lower paging cycle. The solution of the embodiment of the present application can overcome the disadvantage of the long paging cycle of the existing terminal device and provide a smaller paging cycle for the terminal device.

[0130] Taking voice service as an example, some communication systems (such as LTE system) require 3s end-to-end delay for voice service, of which the paging delay requirement is 1s. Considering the time of paging detection and ACK / NACK feedback, the paging cycle of the terminal device should be less than 1s. Therefore, the paging cycle of the central node in the embodiment of the present application should be less than 1s.

[0131] In addition, when the central node receives paging indications for multiple terminal devices, the start and end times of the paging cycles of these terminal devices may not overlap. Therefore, the central node may need to configure a smaller paging cycle to facilitate detection of the paging indications of all terminal devices.

[0132] The network device (access network device or core network) or terminal device in the embodiment of the present application can determine whether to implement the solution of the embodiment of the present application based on whether there is a connection between the terminal device and the central node. The terminal device can report the indication information of whether it is connected to the central node to the access network device or the core network. For example, if the terminal device is connected to the central node, the terminal device can send a fourth indication information to the access network device or the core network. The fourth indication information is used to indicate that the terminal device is connected to the access network device. Upon receiving the fourth indication information sent by the terminal device, the access network device can send a second indication information to the central node. Upon receiving the fourth indication information sent by the terminal device, the core network can send a third indication information to the central node.

[0133] If there is no connection between the terminal device and the central node, a traditional method can be used to transmit paging information. For example, the access network device sends paging indication information to the terminal device, and the terminal device wakes up periodically to perform paging detection.

[0134] In some embodiments, whether the terminal device is connected to the central node can be indicated by whether the terminal device has a WiFi connection. For example, if the terminal device has a WiFi connection, it means that the terminal device is connected to the central node. The terminal device can report the information of whether there is a WiFi connection to the network device, so that the network device can determine whether to adopt the solution of the embodiment of the present application.

[0135] In some embodiments, the network device may determine whether the terminal device has activated the mobile communication module according to the service type of the terminal device. Further, the network device may determine whether to adopt the solution of the embodiment of the present application according to whether the terminal device has activated the mobile communication module. If the terminal device has activated the mobile communication module, the solution of the embodiment of the present application may not be implemented; if the terminal device has not activated the mobile communication module, the solution of the embodiment of the present application may be implemented or may not be implemented.

[0136] For example, if the terminal device has a data service, the mobile communication module of the terminal device is activated, and the network device may not implement the solution of the embodiment of the present application.

[0137] For another example, if the terminal device has only voice services but no data services, the terminal device may have a mobile communication module enabled or may not have a mobile communication module enabled. In this case, the network device may determine whether to adopt the solution of the embodiment of the present application based on the status information reported by the terminal device. For example, the network device may determine whether to adopt the solution of the embodiment of the present application based on whether the terminal device has a WiFi connection.

[0138] In addition, considering security issues, if the terminal device is connected to a public WiFi, the solution of the embodiment of the present application may not be implemented, and the terminal device still performs paging detection in a traditional manner.

[0139] The solutions described above can be implemented separately or in combination with each other, and the embodiments of the present application do not specifically limit this. For example, both the access network device and the core network can send a paging indication to the central node, that is, the access network device can send the second indication information to the central node, and the core network can also send the third indication information to the central node. By transmitting the paging indication in two ways, the reliability of the message transmission can be guaranteed.

[0140] The solution of the core network sending data to the terminal device through the central node does not depend on the paging scenario and can be applied to any scenario, such as a voice call scenario. In other words, the data sent by the core network can be paging data or other data. To simplify the description, the solutions not described in detail below can refer to the description above.

[0141] In some embodiments, the core network may send the first data to the central node. After receiving the first data, the central node may send the first data to the terminal device. Optionally, the central node may send the first data to the terminal device by transparent transmission. The first data may be paging data or other data, such as voice service data. In an embodiment of the present application, the core network may encapsulate the data for the terminal device into a data packet, such as APP data, and then send the data packet to the terminal device through the central node.

[0142] The terminal device in the embodiment of the present application may be in the RRC_IDLE state, may be in the RRC_CONNECTED state, or may be in the RRC_INACTIVE state. In other words, no matter what state the terminal device is in, the core network may directly send data to the terminal device through the central node.

[0143] The above describes the paging process of the terminal device, and the following describes the random access process of the terminal device. The events that trigger the terminal device to perform random access include one or more of the following: initial RRC connection; RRC connection reestablishment; cell switching; downlink data arrival (such as PDCCH arrival); uplink data arrival; uplink data arrival when there is no physical uplink control channel (PUCCH) resource available with a scheduling request (SR); scheduling request failure; the terminal device enters the RRC_CONNECTED state from the RRC_INACTIVE state; specific system information request; activation of NR cells for non-standalone networking (NSA); beam recovery, etc.

[0144] There are two random access methods: one is contention-based random access and the other is non-contention-based random access. Figure 6 and Figure 7 These two random access methods are described.

[0145] Figure 6 It is a flowchart of a contention-based random access method provided in an embodiment of the present application, and the method includes steps S610 to S640.

[0146] In step S610, the terminal device sends a message 1 (message 1, MSG1) in a random access process to the network device, where the message 1 includes a preamble.

[0147] The terminal device can select a random access channel (RACH) resource and a preamble, and send the selected preamble on the selected resource. The RACH resource may also be referred to as a physical random access channel (PRACH) resource.

[0148] The network device may send the RACH configuration information to the terminal device in the form of broadcast. The RACH configuration information may include the configuration information of the RACH time-frequency resources and the configuration information of the initial preamble root sequence.

[0149] The network device can configure a shared preamble pool for the terminal device. The preambles in the preamble pool are shared by multiple terminal devices. The terminal device can select the preamble based on a certain strategy. Since the preamble is shared by multiple terminal devices, there will be a conflict in which multiple terminal devices select the same preamble. In order to resolve the conflict, the network device can use a subsequent resolution mechanism to handle the conflict.

[0150] In step S620, the network device sends MSG2 to the terminal device, and the MSG2 may also be called a random access response (RAR). The MSG2 may be carried by the PDCCH.

[0151] After the terminal device sends MSG1, it can open a random access response time window and monitor the PDCCH scrambled by the random access radio network temporary identifier (RA-RNTI) within the time window. RA-RNTI is related to the time-frequency resources of the RACH used by the terminal device to send MSG1. After receiving the PDCCH, the terminal device can use the RA-RNTI to decode the PDCCH.

[0152] MSG2 may also include a preamble code sent by the terminal device. If the terminal device receives a PDCCH scrambled with RA-RNTI and MSG2 includes the preamble code sent by itself, the terminal device may consider that the random access response has been successfully received.

[0153] After the terminal device successfully receives the PDCCH, the terminal device can obtain the physical downlink shared channel (PDSCH) scheduled by the PDCCH, wherein the PDSCH contains the RAR. The RAR may contain multiple information. For example, the subheader of the RAR may contain a backoff indicator (BI), which may be used to indicate the backoff time for retransmitting MSG1; the random access preamble identification (RAPID) in the RAR indicates the preamble index to which the network device responds; the payload in the RAR may contain a timing advance group (TAG), which may be used to adjust the uplink timing; the RAR may also include an uplink grant (UL grant) for scheduling uplink resource indications for MSG3; the RAR may also include a temporary cell-radio network temporary identifier (C-RNTI), and for the initial access terminal device, the terminal device may use the temporary C-RNTI to decode the PDCCH of MSG4.

[0154] If the terminal device does not receive the RAR within the random access response time window, or fails to verify successfully, it indicates that the response has failed. In this case, if the number of random access attempts of the terminal device is less than the upper limit (such as 10 times), the terminal device can continue to attempt random access. If the number of attempts is greater than the upper limit, it indicates that the random access has failed.

[0155] Step S630: The terminal device sends MSG3 to the network device. The terminal device may send MSG3 on the uplink grant scheduled by the network device. The MSG3 may also be called an RRC connection establishment request message.

[0156] The MSG3 is mainly used to inform the network device of what event triggered the random access process. The MSG3 includes the C-RNTI of the terminal device. In different scenarios, the MSG3 sent by the terminal device will be different. The following are some examples of scenarios.

[0157] For example, for the RRC connection establishment scenario, the terminal device can send an RRC connection establishment request message through MSG3, and the RRC connection establishment request message can carry the non-access stratum (NAS) UE_ID. The RRC connection establishment request message can be transmitted through the common control channel (CCCH) in the radio link control (RLC) layer transmission (TM). The message is not segmented.

[0158] For another example, for an RRC connection reestablishment request, the terminal device may send an RRC reestablishment request message through MSG3, the RRC reestablishment request message does not carry a NAS message, and the RRC reestablishment request message may be transmitted through the CCCH of the RLC layer using TM. The message is not segmented.

[0159] For another example, for a cell handover scenario, if the terminal device accesses the target cell and there is no dedicated preamble during the handover process, contention-based random access can be triggered. The terminal device can send an RRC handover confirmation message and C-RNTI via MSG3. The RRC handover confirmation message and C-RNTI can be transmitted via a dedicated control channel (DCCH). In some embodiments, MSG3 can also carry a buffer status report (BSR).

[0160] Step S640: The network device sends MSG4 to the terminal device.

[0161] The MSG4 has two functions, one is for contention conflict resolution, and the other is to send an RRC configuration message to the terminal device. If the terminal device carries C-RNTI in MSG3, MSG4 uses the PDCCH scrambled by the C-RNTI for scheduling. Accordingly, the terminal device can use the C-RNTI in MSG3 to decode the PDCCH to obtain MSG4. If the terminal device does not carry C-RNTI in MSG3, such as initial access, MSG4 can use the PDCCH scrambled by the temporary C-RNTI for scheduling. Accordingly, the terminal device can use the temporary C-RNTI in MSG2 to decode the PDCCH to obtain MSG4. After successfully decoding the PDCCH, the terminal device obtains the PDSCH carrying MSG4. The terminal device can compare the common control channel (CCCH) service data unit (SDU) in the PDSCH with the CCCH SDU in MSG3. If the two are the same, it means that the contention resolution is successful.

[0162] Figure 7 This is a flow chart of a non-contention-based random access method provided by an embodiment of the present application. The method includes steps S710 to S730.

[0163] In step S310, the network device sends the preamble configuration information to the terminal device, which includes the preamble and RACH resources required in the random access process. The preamble is a dedicated preamble allocated by the network device to the terminal device. The dedicated preamble can be notified to the terminal device through RRC signaling or physical layer (PHY) signaling (such as DCI in PDCCH). Using a dedicated preamble will not cause conflicts with other terminal devices.

[0164] In step S720, the terminal device may send the MSGA to the network device according to the preamble configuration information, that is, the terminal device may send the preamble to the network device on the RACH resource.

[0165] In step S730, the network device sends a MSGB to the terminal device, and the MSGB may include a RAR. After the terminal device receives the RAR, it indicates that the random access process is finished.

[0166] As mentioned above, in order to improve the communication performance of the terminal device, the terminal device can access the central node, and the central node provides services for the terminal device. For the scenario where the terminal device is connected to the central node, how to save the power consumption of the terminal device during the random access process is an urgent problem to be solved.

[0167] Based on this, the embodiment of the present application provides a method for wireless communication, by having the central node send the preamble code instead of the terminal device, so as to save the power consumption of the terminal device sending the preamble code, thereby saving the power consumption of the terminal device during the random access process. Since the central node itself is also a terminal device, the central node can use its own ability to connect to the network device to assist the terminal device in performing random access, thereby achieving the purpose of energy saving.

[0168] Combine the following Figure 8 , the wireless communication method of the embodiment of the present application is introduced. Figure 8 The method shown includes steps S810 to S820.

[0169] In step S810, the terminal device sends a request message to the central node. The request message is used to request the central node to send the preamble of the terminal device to the network device. The preamble can be a preamble of a random access process based on contention or a preamble of a random access process based on non-contention.

[0170] The central node in the embodiment of the present application can be one or more of the following devices: CPE, WiFi base station, road side unit in the side communication system, and central node in the side communication system.

[0171] The WiFi base station in the embodiment of the present application can provide a WiFi signal for the terminal device. The WiFi base station may have the ability to perform uplink synchronization and / or downlink synchronization with the network device. The downlink synchronization capability may include obtaining the cell ID or PCI / PCID of the access cell, or obtaining the cell ID or PCI / PCID of the cell with the largest receiving power, or obtaining the cell ID or PCI / PCID of several cells with the best receiving power. The uplink synchronization capability may include obtaining the TA sent by the base station.

[0172] The embodiment of the present application does not specifically limit the manner in which the terminal device sends the request message to the central node. For example, the terminal device may send the request message to the central node via a WiFi signal and / or a WiFi sequence. The WiFi sequence may be, for example, a WiFi beacon. The WiFi signal may be a WiFi pilot signal.

[0173] In step S820, in response to the request message, the central node sends a preamble code of the terminal device to the network device.

[0174] Since the distance between the terminal device and the central node is relatively short, the power consumption required by the terminal device to send a message to the central node is less than the power consumption required by the terminal device to send a message to the network device. Therefore, the central node sends the preamble code instead of the terminal device, which can save the power consumption of the terminal device.

[0175] In some embodiments, the request message may include one or more of the following information: the format of the preamble code, the sequence of the preamble code. For contention-based random access, the network device may broadcast a preamble code pool to the terminal device. As a terminal device, the central node may also receive a preamble code pool configured by the network device. Therefore, the terminal device needs to indicate the format of the preamble code to be sent and / or the sequence of the preamble code to the central node, and the central node may select a suitable preamble code from the preamble code pool for sending based on the format of the preamble code and / or the sequence of the preamble code.

[0176] Of course, in some embodiments, the terminal device may also directly send the preamble to the central node, and the central node transmits the preamble to the network device. In this process, the central node may send the preamble to the network device in a transparent transmission manner.

[0177] In some embodiments, the request message may further include indication information, the indication information being used to indicate a sending time window for the central node to send the preamble code. The central node may send the time window of the terminal device to the network device within the sending time window.

[0178] Of course, in some embodiments, the sending time window may be predefined in the protocol, or may be configured by the network device to the terminal device and / or the central node, or may be negotiated between the terminal device and the central node. The embodiments of the present application do not specifically limit this.

[0179] Subsequent steps in the random access process may be performed by the terminal device or by the central node. In some embodiments, the request message may also be used to indicate whether the central node performs the first operation in the random access process instead of the terminal device. The first operation includes one or more of the following operations: receiving MSG2; sending MSG3; receiving MSG4.

[0180] If the request message instructs the central node to perform the first operation in the random access process on behalf of the terminal device, the central node will perform up to the first operation and will not perform operations after the first operation in the random access process. Operations after the first operation are performed by the terminal device itself. For example, if the request message instructs the central node to receive MSG2 on behalf of the terminal device, the central node will not send MSG3 and receive MSG4 on behalf of the terminal device.

[0181] The RAR in the embodiment of the present application can be detected by the terminal device or by the central node. If the RAR is detected by the central node, the central node sends the information received in the RAR to the terminal device. For example, the central node can notify the terminal device of the received UL Grant, TA, temporary C-RNTI and other information. The terminal device can use this information to perform subsequent steps of random access.

[0182] In some embodiments, the entire random access of the terminal device can be performed by the central node. In this case, the terminal device needs to inform the central node of the purpose and relevant parameters of the random access. The purpose of the random access may include, for example, RRC connection establishment, RRC connection reconstruction, cell switching, etc. For parameters designed for security such as NAS UEID, the terminal device can use a temporary NAS UE ID, that is, the terminal device sends the temporary NAS UE ID to the central node, so that the central node uses the temporary NAS UE ID to help the terminal device complete the random access. After the random access of the terminal device is completed, the terminal device can change the temporary NAS UE ID to the UE ID of the terminal device. After the random access competition is successful, the central node can notify the terminal device that the random access is completed. In this way, the central node only needs to notify the terminal device of the random access result, which can maximize the power consumption of the terminal device.

[0183] If the RAR is detected by the terminal device, the terminal device can detect the RAR sent by the network device after sending the request message to the central node. In some embodiments, the terminal device can detect the RAR after the sending time window. For example, the terminal device can detect the RAR sent by the network device in the first time period, and the first time period is after the sending time window. The detection of the RAR by the terminal device can ensure the security of the data.

[0184] Combination of the above Figures 1 to 8 , describes the method embodiment of the present application in detail, and the following is combined with Figures 9 to 15 , describes the device embodiment of the present application in detail. It should be understood that the description of the method embodiment corresponds to the description of the device embodiment, so the parts not described in detail can refer to the previous method embodiment.

[0185] Fig. 9 1 is a schematic structural diagram of a wireless communication device provided in an embodiment of the present application. The device may be a terminal device. Fig. 9 The terminal device shown may be any of the terminal devices described above. The terminal device 900 includes a receiving unit 910 .

[0186] See also Fig. 9 The receiving unit 910 may be configured to receive first indication information sent by the central node, wherein the first indication information is used to instruct the network device to page the terminal device.

[0187] In some embodiments, the sending of the first indication information is triggered by one or more of the following events: the central node receives second indication information sent by an access network device, and the second indication information is used to instruct the network device to page the terminal device; the central node receives third indication information sent by the core network, and the third indication information is used to instruct the network device to page the terminal device.

[0188] In some embodiments, the second indication information is carried by a paging advance indication PEI of the terminal device, and the PEI of the terminal device indicates that the terminal device receives paging indication information.

[0189] In some embodiments, the PEI of the terminal device is carried in the first control information, and the first control information also includes one or more of the following information: the PEI of the central node and the PEI of other terminal devices.

[0190] In some embodiments, the PEIs of all terminal devices covered by the central node are carried in the same control information, and the PEI of the terminal device is represented by the serial number i in the PEI bit corresponding to the central node. PEI Determined according to the following formula:

[0191] i PEI =mod(n intraUEID ,N)+i begin

[0192] Where N is the number of PEI bits corresponding to the central node, i begin is the bit number of the PEI of the first terminal device in the PEI bit corresponding to the central node, n intraUEID It is the serial number of the terminal device among all the terminal devices covered by the central node.

[0193] In some embodiments, the second indication information is carried in a paging message of the central node.

[0194] In some embodiments, the second indication information includes an identification of the terminal device.

[0195] In some embodiments, the second indication information is obtained by the central node performing paging detection based on the paging configuration information of the terminal device.

[0196] In some embodiments, the third indication information includes one or more of the following information: an Internet Protocol IP address of the central node, an identifier of the central node, an IP address of the terminal device, and an identifier of the terminal device.

[0197] In some embodiments, the receiving unit 910 is further used to: receive a paging message through the central node in response to the first indication information.

[0198] In some embodiments, the paging message is sent by a core network to the central node.

[0199] In some embodiments, the apparatus 900 further includes an activation unit 920, configured to activate a communication module for communicating with an access network device in response to the first indication information; and the receiving unit 910, configured to receive a paging message sent by the access network device through the communication module.

[0200] In some embodiments, the apparatus 900 further includes: a sending unit 930, configured to send fourth indication information to the network device, wherein the fourth indication information is used to indicate that the terminal device is connected to the central node.

[0201] In some embodiments, the first indication information is received by a wake-up device in the terminal device.

[0202] In some embodiments, the paging cycle of the central node is less than or equal to the paging cycle of the terminal device.

[0203] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

[0204] Fig.10 1 is a schematic structural diagram of a wireless communication device provided by an embodiment of the present application. The device may be a central node. Fig.10 The central node shown may be any central node described above. The central node 1000 includes a sending unit 1010 .

[0205] See also Fig.10 The sending unit 1010 may be configured to send first indication information to the terminal device, wherein the first indication information is used to instruct the network device to page the terminal device.

[0206] In some embodiments, the sending of the first indication information is triggered by one or more of the following events: the central node receives second indication information sent by an access network device, and the second indication information is used to instruct the network device to page the terminal device; the central node receives third indication information sent by the core network, and the third indication information is used to instruct the network device to page the terminal device.

[0207] In some embodiments, the second indication information is carried by a paging advance indication PEI of the terminal device, and the PEI of the terminal device indicates that the terminal device receives paging indication information.

[0208] In some embodiments, the PEI of the terminal device is carried in the first control information, and the first control information also includes one or more of the following information: the PEI of the central node and the PEI of other terminal devices.

[0209] In some embodiments, the PEIs of all terminal devices covered by the central node are carried in the same control information, and the PEI of the terminal device is represented by the serial number i in the PEI bit corresponding to the central node. PEI Determined according to the following formula:

[0210] i PEI =mod(n intraUEID ,N)+i begin

[0211] Where N is the number of PEI bits corresponding to the central node, i begin is the bit number of the PEI of the first terminal device in the PEI bit corresponding to the central node, n intraUEID It is the serial number of the terminal device among all the terminal devices covered by the central node.

[0212] In some embodiments, the second indication information is carried in a paging message of the central node.

[0213] In some embodiments, the second indication information includes an identification of the terminal device.

[0214] In some embodiments, the second indication information is obtained by the central node performing paging detection based on the paging configuration information of the terminal device.

[0215] In some embodiments, the third indication information includes one or more of the following information: an Internet Protocol IP address of the central node, an identifier of the central node, an IP address of the terminal device, and an identifier of the terminal device.

[0216] In some embodiments, the sending unit 1010 is further used to: send a paging message to the terminal device.

[0217] In some embodiments, the paging message is sent by a core network to the central node.

[0218] In some embodiments, the first indication information is received by a wake-up device in the terminal device.

[0219] In some embodiments, the paging cycle of the central node is less than or equal to the paging cycle of the terminal device.

[0220] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

[0221] Fig.11 1 is a schematic structural diagram of a wireless communication device provided in an embodiment of the present application. The device may be an access network device. Fig.11 The access network device shown may be any of the access network devices described above. The access network device 1100 includes a sending unit 1110 .

[0222] The sending unit 1110 may be used to send second indication information to the central node so that the central node sends first indication information to the terminal device, where the first indication information is used to instruct the network device to page the terminal device.

[0223] In some embodiments, the second indication information is carried by a paging advance indication PEI of the terminal device, and the PEI of the terminal device indicates that the terminal device receives paging indication information.

[0224] In some embodiments, the PEI of the terminal device is carried in the first control information, and the first control information also includes one or more of the following information: the PEI of the central node and the PEI of other terminal devices.

[0225] In some embodiments, the PEIs of all terminal devices covered by the central node are carried in the same control information, and the PEI of the terminal device is represented by the serial number i in the PEI bit corresponding to the central node. PEI Determined according to the following formula:

[0226] i PEI =mod(n intraUEID ,N)+i begin

[0227] Where N is the number of PEI bits corresponding to the central node, i begin is the bit number of the PEI of the first terminal device in the PEI bit corresponding to the central node, n intraUEID It is the serial number of the terminal device among all the terminal devices covered by the central node.

[0228] In some embodiments, the second indication information is carried in a paging message of the central node.

[0229] In some embodiments, the second indication information includes an identification of the terminal device.

[0230] In some embodiments, the second indication information is obtained by the central node performing paging detection based on the paging configuration information of the terminal device.

[0231] In some embodiments, the sending unit 1110 is further used to: send a paging message to the terminal device.

[0232] In some embodiments, the first indication information is received by a wake-up device in the terminal device.

[0233] In some embodiments, the paging cycle of the central node is less than or equal to the paging cycle of the terminal device.

[0234] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a sidewalk communication system, and a central node in a sidewalk communication system.

[0235] In some embodiments, the sending unit 1110 is used to: upon receiving fourth indication information sent by the terminal device, send second indication information to the central node, wherein the fourth indication information is used to indicate that the terminal device is connected to the central node.

[0236] Fig.12 1 is a schematic structural diagram of a wireless communication device provided by an embodiment of the present application. The device may be a core network. Fig.12 The core network shown may be any one of the core networks described above. The core network 1200 includes a sending unit 1210 .

[0237] See also Fig.12 The sending unit 1210 may be configured to send third indication information to the central node so that the central node sends first indication information to the terminal device, wherein the first indication information is used to instruct the network device to page the terminal device.

[0238] In some embodiments, the sending unit 1210 is further used to: send a paging message to the central node, so that the central node transmits the paging message to the terminal device.

[0239] In some embodiments, the first indication information is received by a wake-up device in the terminal device.

[0240] In some embodiments, the paging cycle of the central node is less than or equal to the paging cycle of the terminal device.

[0241] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

[0242] In some embodiments, the sending unit 1210 is used to: upon receiving fourth indication information sent by the terminal device, send third indication information to the central node, wherein the fourth indication information is used to indicate that the terminal device is connected to the central node.

[0243] Fig.13 1 is a schematic structural diagram of a wireless communication device provided in an embodiment of the present application. The device may be a terminal device. Fig.13 The terminal device shown may be any of the terminal devices described above. The terminal device 1300 includes a sending unit 1310 .

[0244] See also Fig.13 The sending unit 1310 may be configured to send a request message to a central node, wherein the request message is configured to request the central node to send a preamble code of the terminal device to a network device.

[0245] In some embodiments, the request message includes one or more of the following information: a format of the preamble code, a sequence of the preamble code.

[0246] In some embodiments, the request message is also used to indicate whether the central node performs a first operation in the random access process, where the first operation includes one or more of the following operations: receiving MSG2; sending MSG3; receiving MSG4.

[0247] In some embodiments, the request message includes indication information, and the indication information is used to indicate a sending time window for the central node to send a preamble code.

[0248] In some embodiments, the apparatus 1300 further includes a detection unit 1320, configured to: detect a random access response sent by the network device in a first time period, wherein the first time period is located after the sending time window.

[0249] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

[0250] Fig.14 1 is a schematic structural diagram of a wireless communication device provided by an embodiment of the present application. The device may be a central node. Fig.14The central node shown may be any central node described above. The central node 1400 includes a receiving unit 1410 and a sending unit 1420 .

[0251] See also Fig.14 The receiving unit 1410 may be configured to receive a request message sent by a terminal device, wherein the request message is used to request the central node to send a preamble code of the terminal device to a network device.

[0252] The sending unit 1420 may be configured to send, by the central node, a preamble code of the terminal device to the network device in response to the request message.

[0253] In some embodiments, the request message includes one or more of the following information: a format of the preamble code, a sequence of the preamble code.

[0254] In some embodiments, the request message is also used to indicate whether the central node performs a first operation in the random access process, where the first operation includes one or more of the following operations: receiving MSG2; sending MSG3; receiving MSG4.

[0255] In some embodiments, the request message includes indication information, and the indication information is used to indicate a sending time window for the central node to send a preamble code; the sending unit 1420 is used to: send the preamble code of the terminal device to the network device within the sending time window.

[0256] In some embodiments, the central node is one or more of the following devices: a user premise equipment CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

[0257] Fig.15 It is a schematic structural diagram of the device of an embodiment of the present application. Fig.15 The dotted line in the figure indicates that the unit or module is optional. The device 1500 can be used to implement the method described in the above method embodiment. The device 1500 can be one or more of a chip, a terminal device, a central node, an access network device, and a core network.

[0258] The device 1500 may include one or more processors 1510. The processor 1510 may support the device 1500 to implement the method described in the method embodiment above. The processor 1510 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0259] The apparatus 1500 may further include one or more memories 1520. The memory 1520 stores a program, which can be executed by the processor 1510, so that the processor 1510 executes the method described in the above method embodiment. The memory 1520 may be independent of the processor 1510 or integrated in the processor 1510.

[0260] The apparatus 1500 may further include a transceiver 1530. The processor 1510 may communicate with other devices or chips through the transceiver 1530. For example, the processor 1510 may transmit and receive data with other devices or chips through the transceiver 1530.

[0261] The present application also provides a computer-readable storage medium for storing a program. The computer-readable storage medium can be applied to a terminal or network device provided in the present application, and the program enables a computer to execute the method performed by the terminal or network device in each embodiment of the present application.

[0262] The embodiment of the present application also provides a computer program product. The computer program product includes a program. The computer program product can be applied to the terminal or network device provided in the embodiment of the present application, and the program enables the computer to execute the method performed by the terminal or network device in each embodiment of the present application.

[0263] The embodiment of the present application also provides a computer program. The computer program can be applied to the terminal or network device provided in the embodiment of the present application, and the computer program enables a computer to execute the method executed by the terminal or network device in each embodiment of the present application.

[0264] It should be understood that in the embodiment of the present application, "B corresponding to A" means that B is associated with A, and B can be determined according to A. However, it should also be understood that determining B according to A does not mean determining B only according to A, and B can also be determined according to A and / or other information.

[0265] It should be understood that the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0266] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0267] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0268] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0269] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0270] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The computer-readable storage medium may be any available medium that can be read by a computer or a data storage device such as a server or data center that includes one or more available media integrated. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0271] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A wireless communication method, characterized in that: include: The terminal device sends a request message to the central node, where the request message is used to request the central node to send a preamble code of the terminal device to a network device.

2. The method according to claim 1, characterized in that The request message includes one or more of the following information: a format of the preamble code and a sequence of the preamble code.

3. The method according to claim 1 or 2, characterized in that: The request message is also used to indicate whether the central node performs a first operation in the random access process instead of the terminal device, where the first operation includes one or more of the following operations: Receive MSG2; Send MSG3; Receive MSG4.

4. The method according to any one of claims 1 to 3, characterized in that The request message includes indication information, and the indication information is used to indicate a sending time window for the central node to send a preamble code.

5. The method according to any one of claims 1 to 4, characterized in that The method further comprises: The terminal device detects the random access response sent by the network device in a first time period, wherein the first time period is after the sending time window.

6. The method according to any one of claims 1 to 5, characterized in that The central node is one or more of the following devices: a user front-end device CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

7. A wireless communication method, characterized in that: include: The central node receives a request message sent by the terminal device, wherein the request message is used to request the central node to send a preamble code of the terminal device to the network device; In response to the request message, the central node sends a preamble code of the terminal device to the network device.

8. The method according to claim 7, characterized in that The request message includes one or more of the following information: a format of the preamble code and a sequence of the preamble code.

9. The method according to claim 7 or 8, characterized in that: The request message is also used to indicate whether the central node performs a first operation in the random access process, where the first operation includes one or more of the following operations: Receive MSG2; Send MSG3; Receive MSG4.

10. The method according to any one of claims 7 to 9, characterized in that: The request message includes indication information, where the indication information is used to indicate a sending time window for the central node to send a preamble; The central node sends a preamble code of the terminal device to the network device, including: The central node sends the preamble code of the terminal device to the network device within the sending time window.

11. The method according to any one of claims 7 to 10, characterized in that: The central node is one or more of the following devices: a user front-end device CPE, a wireless fidelity WiFi base station, a road side unit in a side communication system, and a central node in a side communication system.

12. A wireless communication device, characterized in that: The device is a terminal device, and the device includes: The sending unit is used to send a request message to the central node, wherein the request message is used to request the central node to send the preamble code of the terminal device to the network device.

13. A wireless communication device, characterized in that: The device is a central node, and the device includes: A receiving unit, configured to receive a request message sent by a terminal device, wherein the request message is used to request the central node to send a preamble code of the terminal device to a network device; A sending unit is used for sending the preamble code of the terminal device to the network device by the central node in response to the request message.

Images