CN114845391B

CN114845391B - Method and device for transmitting paging message

Info

Publication number: CN114845391B
Application number: CN202210101410.XA
Authority: CN
Inventors: 徐海博; 邝奕如; 纳坦·爱德华·坦尼
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-01-25
Filing date: 2017-03-24
Publication date: 2024-04-23
Anticipated expiration: 2037-03-24
Also published as: CN109923912A; CN109923912B; CN114845391A; WO2018137284A1

Abstract

The application discloses a method and a device for transmitting paging messages, relates to the technical field of communication, and can solve the problem that paging messages sent by a base station cannot be received under the condition that eRemoteUE is out of coverage of the base station. The application receives a first message sent by network equipment through first user equipment, wherein the first message is used for paging second user equipment, the first message at least comprises paging information of the second user equipment, the first user equipment sends the second message to the second user equipment, and the second message comprises the paging information; the method comprises the steps that a side uplink connection is established between first user equipment and second user equipment, the first user equipment is in an RRC idle state, a first message is received through a paging channel, the first message is a broadcast message, and the first user equipment generates a second message under the condition that the first message comprises the paging information; or the first user equipment is in an RRC connection state, and the first message is contained in an RRC connection reconfiguration message; the paging information at least comprises the equipment identifier of the second user equipment. The scheme provided by the application is suitable for being adopted when paging messages are transmitted.

Description

Method and device for transmitting paging message

The present application claims priority from chinese patent office, application number 201710061368.2, chinese patent application entitled "a method of transmitting paging messages" filed 25 in 2017, 01, the entire contents of which are incorporated herein by reference.

Technical Field

The present application relates to the field of wireless communications technologies, and in particular, to a method and an apparatus for transmitting paging messages.

Background

Currently, two communication modes exist between a User Equipment (UE) and a base station, namely a direct connection communication mode and a non-direct connection communication mode. The direct connection communication mode refers to that the UE is directly connected to the base station and performs communication. The non-direct connection communication mode refers to that a Remote user equipment (Remote User Equipment, remote UE) is connected with a base station through a Relay user equipment (Relay User Equipment, relay UE), and the Relay UE can implement data forwarding between the base station and the Remote UE through a network protocol (Internet Protocol, IP) layer (layer three). However, in the process of forwarding data by the Relay UE, the packet data convergence protocol (PACKET DATA Convergence Protocol, PDCP) layer of the Remote UE may solve the data of the Remote UE, so that the data of the Remote UE has potential safety hazards and other problems. To address these problems, the Relay UE may forward data by relaying data based on data above the radio link control (Radio Link Control, RLC) layer and below the PDCP layer, in which case the remote user equipment may be referred to as an Evolved remote user equipment (Evolved Remote UE, eRemote UE) and the Relay UE may be referred to as an Evolved Relay UE (eRelay UE).

Wherein eRemote UE may receive control messages such as system messages and paging messages sent by the base station through a direct link with the base station, and perform data plane data transmission with the base station through a side link (sidelink) with eRelay UE. When the core network needs to send data to eRemote UE in rrc_idle state, it needs to send a paging message to eRemote UE by the base station to trigger eRemote UE to enter rrc_connected state, eRemote UE only needs to wake up once in one paging cycle, and the base station will send a paging message to eRemote UE through downlink control channel (Physical Downlink Control Channel, PDCCH) at the point of time when eRemote UE wakes up.

However, if eRemote UE is out of coverage of the base station, the paging message sent by the base station through the PDCCH cannot be accepted, resulting in the base station failing to establish a communication connection with eRemote UE.

Disclosure of Invention

The embodiment of the application provides a method and a device for transmitting paging messages, which can solve the problem that paging messages sent by a base station cannot be received under the condition that eRemote UE is out of coverage of the base station.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical scheme:

in a first aspect, an embodiment of the present application provides a method for transmitting a paging message, the method including:

The first user equipment receives a first message sent by the network equipment, wherein the first message is used for paging the second user equipment, and the first message at least comprises paging information of the second user equipment. And then the first user equipment generates a second message according to the first message, wherein the second message is used for paging the second user equipment, and the second message contains paging information of the second user equipment. And then the first user equipment determines the monitoring time of the second user equipment for monitoring the second message and acquires the resource for sending the second message, and the first user equipment can send the second message to the second user equipment by using the resource for sending the second message at the monitoring time.

The paging information of the second user equipment comprises a second user equipment identifier and core network domain information. The first ue may be eRemote UE, the second ue may be eRemote UE, the network device may be a base station, and the second ue identity may be IMSI, S-TMSI, IMSI mod 1024, or other identity that may represent the identity of the second ue.

The base station can send the first message to the first user equipment, and then the first user equipment determines the monitoring time of the second user equipment for monitoring the second message, and the first user equipment can send the second message for paging the second user equipment to the second user equipment in the monitoring time.

In one possible design, before the first ue determines the listening time, the information for determining the listening time is acquired first, and the method for acquiring the information for determining the listening time is as follows:

The first user equipment receives a third message sent by the second user equipment, wherein the third message carries information for determining the monitoring time; or the first user equipment receives a fourth message sent by the network equipment, wherein the fourth message carries information for determining the monitoring time.

Therefore, before the first user equipment determines the monitoring time, the second user equipment or the network equipment can send the information for determining the monitoring time to the first user equipment, so that the first user equipment can determine the monitoring time of the second user equipment, the time for sending the second message by the first user equipment is the same as the time for the second user equipment to monitor the second message, and even if the second user equipment is not in the coverage area of the base station, the paging message can be received by the second user equipment, and compared with the paging message transmitted to the second user equipment by the base station through a downlink, the power consumed by the first user equipment for transmitting the paging message to the second user equipment through a sidelink is lower.

In one possible design, the information sent by the second user equipment or the network equipment to the first user equipment for determining the listening time includes at least one of a second user equipment identification, a specific paging cycle of the second user equipment, and a default paging cycle of the system.

In one possible design, before determining the listening time, the first user equipment needs to determine a first identity for determining the listening time, and also needs to determine a first paging cycle for determining the listening time.

The first identifier is a first user equipment identifier or a second user equipment identifier, and the first identifier used for determining the monitoring time by the first user equipment is the same as the first identifier used for determining the monitoring time by the second user equipment, namely if the first identifier adopted by the first user equipment is the first user equipment identifier, the first identifier adopted by the second user equipment is also the first user equipment identifier; if the first identifier adopted by the first user equipment is the second user equipment identifier, the first identifier adopted by the second user equipment is also the second user equipment identifier.

The first paging cycle is the specific paging cycle or the smaller of the specific paging cycle and the default paging cycle of the system. Wherein the specific paging cycle is UE-SPECIFIC PAGING CYCLE of the second UE eRemote UE, and the default paging cycle is default PAGING CYCLE broadcasted by the base station. The first user equipment and the second user equipment adopt the same first paging cycle when determining the monitoring time.

Therefore, after the first user equipment determines the first identifier for determining the monitoring time and the first paging cycle for determining the monitoring time, the process of determining the monitoring time can be further completed according to the combination of the first identifier and the first paging cycle, so that the first user equipment can send a second message to the second user equipment on the sidelink, and the second user equipment can receive the second message on the sidelink.

In one possible design, before the first user equipment determines the listening time, the first user equipment may further receive resource pool configuration information configured by the network equipment for transmitting the second message, where the resource pool configuration information includes at least one of the following information:

A resource pool offset;

The cycle length of the resource pool;

a bitmap for indicating a subframe in which the second message is transmitted;

frequency domain resource locations for transmitting the second message.

In one possible design, the first ue determines a listening time for the second ue to listen to the second message, which may be specifically implemented as:

the first user equipment determines the position of a wireless frame and the position of a subframe monitored by the second user equipment in the side uplink sidelink according to the first identifier, the first paging period and nB, wherein nB is the number of subframes contained in one paging period.

Therefore, after the first user equipment determines the position of the radio frame and the position of the subframe monitored by the second user, the second message can be sent on the determined radio frame and subframe, so that the second user equipment does not need to monitor the sidelink all the time, and can receive the second message only by waking up when the second message needs to be monitored.

In one possible design, the first ue determines, according to the first identifier, the first paging cycle, and nB, a location of a radio frame and a location of a subframe monitored by the second ue in the side uplink sidelink, which may be specifically implemented as:

The first user equipment determines the position of a monitored radio frame and the position of a subframe when the second user equipment monitors the downlink according to the first identifier, the first paging cycle and the nB, and then the first user equipment determines the position of the monitored radio frame and the position of the subframe of the second user equipment in the side downlink side link according to the position of the monitored radio frame and the position of the monitored subframe when the second user equipment monitors the downlink.

In one possible design, the first user equipment may determine the location of the monitored radio frame and the location of the subframe when the first user equipment monitors the downlink according to the following formula.

Equation 1: SFN mod t= (tdiv N) × (ue_id mod N)

Equation 2: i_s=floor (ue_id/N) mod Ns

Wherein SFN is the position of the subframe; t is a first paging cycle; n is min (T, nB) for indicating the number of radio frames included in one first paging cycle; max (1, nb/T) for indicating the number of subframes included in one radio frame; the ue_id is the first identity.

The position of the monitored radio frame when the second user equipment monitors the downlink can be determined by solving the SFN according to the formula 1, i_s can be solved according to the formula 2, and then the position of the monitored radio frame when the second user equipment monitors the downlink can be determined according to the corresponding relation table of the value of i_s and the value of NS and the subframe position. The corresponding relation tables of the i_s value and the NS value corresponding to the FDD system and the TDD system and the subframe position are different.

In one possible design, the position of the subframe monitored by the second user equipment in the sidelink is the position of the monitored subframe when the second user equipment monitors the downlink, and the first offset is a positive integer greater than or equal to 0; or the position of the subframe monitored by the second user equipment in the sidelink is the position of the monitored subframe when the second user equipment monitors the downlink, and after adding a second offset, the first subframe in the resource pool can be used for transmitting the second message, wherein the second offset is a positive integer greater than or equal to 0.

In one possible design, for an FDD system, the location of the radio frame and the location of the subframe that the second user equipment listens to when listening to the downlink are the same as the location of the radio frame and the location of the subframe that the second user equipment listens to in the sidelink;

For the TDD system, the position of the radio frame monitored by the second ue when monitoring the downlink is the same as the position of the radio frame monitored by the second ue in the sidelink. According to different TDD configurations, the position of the subframe monitored by the second user equipment when the second user equipment monitors the downlink has different corresponding relations with the position of the subframe monitored by the second user equipment in the sidelink.

One possible correspondence is: when a second terminal needs to monitor a subframe number 0 in a downlink, the subframe number, which corresponds to a TDD configuration 0 to a TDD configuration 6 and needs to monitor in a sidelink, of the second terminal is 2;

When the number of the subframe to be monitored in the downlink by the second terminal is 1, the numbers of the subframes to be monitored in the sidelink by the second terminal corresponding to the TDD configuration 0 to the TDD configuration 6 are respectively: 3.3, 2, 3,2, 3;

When the number of the subframe to be monitored in the downlink by the second terminal is 5, the numbers of the subframes to be monitored in the sidelink by the second terminal corresponding to the TDD configuration 0 to the TDD configuration 6 are respectively: 7. 7, 2, 7;

when the number of the subframe to be monitored in the downlink by the second terminal is 6, the numbers of the subframes to be monitored in the sidelink by the second terminal corresponding to the TDD configuration 0 to the TDD configuration 6 are respectively: 8. 8, 7, 3,2, 8.

In one possible design, the first ue determines a listening time for the second ue to listen to the second message, specifically including:

The first user equipment determines the number N of resource pool periods contained in one first paging period of the second user equipment and the number M of subframes used for sending the second message in each resource pool period according to the resource pool configuration information, the first identification and the first paging period, and then the first user equipment determines the number of the resource pool periods, which is needed by the second user equipment to monitor the second message, in one first paging period, wherein the number of the resource pool periods is the first identification mod N. Then the first user equipment determines that the second user equipment needs to monitor the subframe number of the second message in a resource pool period, wherein the subframe number is floor (first identifier/N) mod M, and the first user equipment can further determine the subframe position monitored by the second user equipment in the sidelink according to the resource pool period number and the subframe number.

In one possible design, the first user equipment determines a listening time for the second user equipment to listen to the second message, which may be specifically implemented as: the first user equipment determines a third offset po_offset according to the first identifier and the first paging cycle, and then the first user equipment determines a frame number and a subframe number of a second message monitored by the second user equipment at the sidelink according to [ frame number x 10+subframe number+sl_offset ] module (first paging cycle) =po_offset, wherein sl_offset is the offset of the resource pool.

In one possible design, if the first ue is in rrc_idle state, after the first ue receives the first message sent by the network device, the first ue may trigger the RRC connection establishment procedure to transition to rrc_ CONNRECTED state. After the first user equipment is converted to the RRC_ CONNRECTED state, the first user equipment and the base station can communicate through the special message, so that the first user equipment can request the base station to acquire resources for transmitting the second message, or the base station actively transmits the resources for transmitting the second message to the first user equipment through the special message, and further, the first user equipment can use the resources provided by the base station to transmit the second message through the sidelink.

In one possible design, when the network device needs to send the first message to the first user device, if the first user device is in the rrc_idle state, the network device triggers an RRC connection establishment procedure of the first user device, so that the first user device transitions to the rrc_ CONNRECTED state. After the first user equipment is converted to the RRC_ CONNRECTED state, the first user equipment and the base station can communicate through the special message, so that the first user equipment can request the base station to acquire resources for transmitting the second message, or the base station actively transmits the resources for transmitting the second message to the first user equipment through the special message, and further, the first user equipment can use the resources provided by the base station to transmit the second message through the sidelink.

In one possible design, the first user equipment obtains the resource for sending the second message, which may be specifically implemented as: the first user equipment sends a fifth message to the network equipment, wherein the fifth message is used for requesting to acquire resources for sending the second message;

The first user equipment receives a sixth message sent by the network equipment, wherein the sixth message comprises resource information or resource pool information which is distributed by the network equipment for the first user equipment and used for sending the second message.

In one possible design, the fifth message includes at least one of the following information:

a request destination for indicating that the purpose of the fifth message is to acquire a resource for transmitting a second message;

Time of sending the second message;

The number of paging information contained in the second message, each second user equipment corresponding to one paging information;

the number of bits contained in the second message.

Wherein each group of paging information comprises a second equipment identifier and core network domain information, and the core network domain information is a CS domain or a PS domain.

In one possible design, the first user equipment obtains the resource for sending the second message, and may be specifically further implemented as:

The first user equipment acquires resources for sending the second message from the first message, wherein the first message contains resource information or resource pool information which is distributed for the first user equipment by the network equipment and is used for sending the second message.

In one possible design, the first user equipment may also receive a first message through the radio resource control layer and generate the second message from the first message by the radio resource control layer.

The second message generated by the first user equipment through the radio resource control layer can be suitable for any short-distance connection technology, is not limited to the sidelink connection, can be WLAN connection and the like, and expands the application range of the method for transmitting the paging message.

In a second aspect, an embodiment of the present application provides a method for transmitting a paging message, the method comprising:

The second user equipment determines the monitoring time for monitoring the second message, the second message is used for paging the second user equipment, the second message comprises paging information of the second user equipment, then the second user equipment monitors the second message sent by the first user equipment in the monitoring time, and when the second message is monitored, the second message is received.

Therefore, the second ue may determine the listening time of listening to the second message first, and may listen to the second message sent by the first ue in the listening time, which is equivalent to that the first ue may transmit the paging message through the sidelink, so that the second message may be received through the sidelink even if the second ue is not in the coverage area of the base station. In addition, the process of transmitting the second message through the sidelink between the first user equipment and the second user equipment consumes less power than transmitting the second message through the downlink between the base station and the second user equipment.

In one possible design, before the second ue determines the listening time for listening to the second message, the method for acquiring the information for determining the listening time includes:

the second user equipment also needs to send a third message to the first user equipment, wherein the third message carries a specific paging cycle of the second user equipment, and then the second user equipment receives a seventh message sent by the first user equipment, and the seventh message carries information for determining the monitoring time.

Therefore, before the first user equipment determines the monitoring time, the first user can receive the information for determining the monitoring time sent by the second user equipment, so that the second user equipment can determine the monitoring time of the second user equipment, the time for the first user equipment to send the second message is the same as the time for the second user equipment to monitor the second message, and even if the second user equipment is not in the coverage area of the base station, paging messages can be received by the second user equipment, and compared with the case that the base station transmits the paging messages to the second user equipment through downlink, the power consumed by the first user equipment for transmitting the paging messages to the second user equipment through sidelink is lower.

In one possible design, the information for determining the listening time includes at least one of a first user equipment identifier, nB, and a system default paging cycle broadcasted by the network device, nB being a number of subframes included in one paging cycle; or alternatively

The information for determining the listening time is resource pool configuration information configured by the network device for transmitting the second message, the resource pool configuration information comprising at least one of:

A resource pool offset;

The cycle length of the resource pool;

a bitmap for indicating a subframe in which the second message is transmitted;

frequency domain resource locations for transmitting the second message.

After the first user equipment obtains the resource pool configuration information for transmitting the second message, the monitoring time of the second user equipment for monitoring the second message can be determined through the resource pool configuration information, the resource for transmitting the second message can be determined, and then the first user equipment can transmit the second message to the second user equipment by using the resource for transmitting the second message at the determined monitoring time, so that the first user equipment and the second user equipment can transmit paging messages by using the sidelink.

In one possible design, the second user equipment determines a first identification for determining the listening time and also needs to determine a first paging cycle for determining the listening time. The first identifier is a first user equipment identifier or a second user equipment identifier, and the first identifiers of the first user equipment and the second user equipment for determining the monitoring time are the same. The first paging cycle is the specific paging cycle or the smaller of the specific paging cycle and the default paging cycle of the system. Wherein the specific paging cycle is UE-SPECIFIC PAGING CYCLE of the second UE eRemote UE, and the default paging cycle is default PAGING CYCLE broadcasted by the base station. The first user equipment and the second user equipment adopt the same first paging cycle when determining the monitoring time.

Therefore, after the second user equipment determines the first identifier for determining the monitoring time and the first paging cycle for determining the monitoring time, the process of determining the monitoring time can be further completed according to the combination of the first identifier and the first paging cycle, and further the sidelink can be monitored in the monitoring time, so that the second message sent by the second user equipment in the monitoring time through the sidelink is received.

In one possible design, the second user equipment determines a listening time for listening to the second message, which may be specifically implemented as:

And the second user equipment determines the position of the subframe monitored by the second user equipment on the side uplink side link according to the first identifier, the first paging cycle and the nB.

In one possible design, the second ue determines, according to the first identifier, the first paging cycle, and nB, a location of a subframe monitored by the second ue on the side uplink sidelink, where the location may be specifically implemented as:

The second user equipment determines the position of the monitored radio frame and the position of the subframe when the second user equipment monitors the downlink according to the first identifier, the first paging cycle and the nB, and then the second user equipment determines the position of the monitored radio frame and the position of the subframe when the second user equipment monitors the downlink according to the position of the monitored radio frame and the monitored subframe when the second user equipment monitors the downlink.

Therefore, after the second user equipment determines the monitoring time for monitoring the second message, the second message can be monitored only by waking up in the monitoring time without monitoring the sidelink all the time.

In one possible design, the second user equipment may determine the location of the monitored radio frame and the location of the subframe when the first user equipment monitors the downlink according to the following formula.

Equation 1: SFN mod t= (tdiv N) × (ue_id mod N)

Equation 2: i_s=floor (ue_id/N) mod Ns

In one possible design, the position of the subframe monitored by the second user equipment in the sidelink is the position of the monitored subframe when the second user equipment monitors the downlink, and the first offset is a positive integer greater than or equal to 0; or alternatively

The position of the subframe monitored by the second user equipment in the sidelink is the position of the monitored subframe when the second user equipment monitors the downlink, and after adding a second offset, the first subframe which can be used for transmitting the second message in the resource pool, wherein the second offset is a positive integer which is more than or equal to 0.

The second user equipment determines the number N of resource pool periods contained in one first paging period of the second user equipment and the number M of subframes used for sending the second message in each resource pool period according to the resource pool configuration information, the first identification and the first paging period. Then, the second user equipment determines that the second user equipment needs to monitor the resource pool period number of the second message in a first paging period, the resource pool period number is the first identifier mod N, the second user equipment further determines that the second user equipment needs to monitor the subframe number of the second message in a resource pool period, the subframe number is floor (first identifier/N) mod M, and further the second user equipment can determine the subframe position monitored by the second user equipment in the sidelink according to the resource pool period number and the subframe number.

In one possible design, the second user equipment determines a listening time for listening to the second message, and may specifically be further implemented as:

The second ue determines a third offset po_offset according to the first identifier and the first paging cycle, and then determines a frame number and a subframe number of the second message to be monitored by the second ue at the sidelink according to [ frame number×10+subframe number+sl_offset ] module (first paging cycle) =po_offset, where sl_offset is a resource pool offset.

In a third aspect, the present application provides an apparatus for transmitting paging messages, where the apparatus may implement a function performed by the first user equipment in the first aspect, where the function may be implemented by hardware, or may be implemented by executing corresponding software by hardware. The hardware or software comprises one or more modules corresponding to the functions.

In one possible design, the apparatus includes a processor and a communication interface in a structure, the processor configured to support the apparatus to perform the corresponding functions of the method described above. The communication interface is for supporting communication between the device and other network elements. The apparatus may also include a memory for coupling with the processor, which holds the program instructions and data necessary for the apparatus.

In a fourth aspect, the present application provides an apparatus for transmitting a paging message, where the apparatus may implement the function performed by the second user equipment in the second aspect, and the function may be implemented by hardware, or may be implemented by executing corresponding software by hardware. The hardware or software comprises one or more modules corresponding to the functions.

In a fifth aspect, the present application provides a system for transmitting paging messages, including the first ue, the second ue and the network device described in the above aspects.

In a sixth aspect, the present application provides a computer storage medium storing computer software instructions for use with the first user device described above, comprising a program designed to perform the aspects described above.

In a seventh aspect, the present application provides a computer storage medium storing computer software instructions for use on the second ue, where the computer storage medium includes a program designed to execute the above aspect.

Compared with the prior art that the base station directly transmits the paging message to the second user equipment, when the second user equipment is not in the signal coverage area of the base station and can not receive the paging message, the base station can firstly transmit the first message to the first user equipment, and then the first user equipment and the second user equipment determine the monitoring time of the second user equipment for monitoring the second message, and the first user equipment can transmit the second message for paging the second user equipment to the second user equipment in the monitoring time.

Drawings

In order to more clearly illustrate the technical solutions of the present application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below.

Fig. 1 is a schematic structural diagram of a network structure according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a logic structure of another network structure according to an embodiment of the present application;

fig. 3 is a flowchart of a method for transmitting paging messages according to an embodiment of the present application;

FIG. 4 is a flow chart of another method for transmitting paging messages according to an embodiment of the present application;

fig. 5 is an exemplary schematic diagram of a method for transmitting paging messages according to an embodiment of the present application;

fig. 6 is an exemplary diagram of another method for transmitting paging messages according to an embodiment of the present application;

fig. 7 is an exemplary diagram of another method for transmitting paging messages according to an embodiment of the present application;

fig. 8 is a schematic diagram of another method for transmitting paging messages according to an embodiment of the present application;

fig. 9 is a schematic diagram of another method for transmitting paging messages according to an embodiment of the present application;

Fig. 10 is a schematic diagram of another method for transmitting paging messages according to an embodiment of the present application;

FIG. 11 is a diagram of another method for transmitting paging messages according to an embodiment of the present application;

fig. 12 is a schematic logic structure diagram of an apparatus for transmitting paging messages according to an embodiment of the present application;

fig. 13 is a schematic logic structure diagram of another apparatus for transmitting paging messages according to an embodiment of the present application.

Detailed Description

The system architecture and the service scenario described in the present application are for more clearly describing the technical solution of the present application, and do not constitute a limitation to the technical solution provided by the present application, and those skilled in the art can know that the technical solution provided by the present application is equally applicable to similar technical problems with the evolution of the system architecture and the occurrence of new service scenarios.

In the present application, the words "exemplary" or "such as" are used to mean serving as an example, instance, or illustration. Any embodiment or design described herein as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "such as" is intended to present related concepts in a concrete fashion.

A User Equipment (UE), also known as a terminal, is a device that provides voice and/or data connectivity to a User, e.g., a handheld device with wireless connectivity, a vehicle mounted device, etc. Common user devices include, for example: a mobile phone, tablet, notebook, palm top, mobile Internet Device (MID), wearable device, such as a smart watch, smart bracelet, pedometer, etc.

A base station, also known as a radio access network (Radio Access Network, RAN) device, is a device that accesses user equipment to a wireless network, including, but not limited to: an evolved Node B (eNB), a radio network controller (radio network controller, RNC), a Node B (Node B, NB), a base station controller (Base Station Controller, BSC), a base transceiver station (Base Transceiver Station, BTS), a Home base station (e.g., home evolved NodeB, or Home Node B, HNB), a BaseBand Unit (BBU), a future network, such as a Node B (gNB) that is continuously evolving in a 5G network (e.g., a network that applies new radio technology). In addition, a Wifi Access Point (AP), a transceiver node (TRP), and the like may be included.

The terms first and second and the like in the description and in the claims, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order of the objects. For example, the first user equipment in the present application may be eRelay UE, and the second user equipment may be eRemote UE.

The principle of the application is as follows: the base station transmits a paging message to be transmitted to eRemote UE to eRelay UE through downlink, and further transmits a paging message to eRemote UE through sidelink by eRelay UE (hereinafter, a paging message transmitted through sidelink to eRemote UE by eRelay UE is referred to as a SL paging message). eRelay UE the method of sending the SL paging message to eRemote UE is: eRelay UE determines eRemote UE the listening time of the paging message by the identity of eRemote UE and the UE-SPECIFIC PAGING CYCLE, and acquires the resources allocated by the base station for transmitting the SL paging message, and further sends the paging message to eRemote UE using the resources allocated by the base station at the listening time eRelay UE. eRemote UE also determine the listening time by communicating with eRelay UE and listen eRelay UE for SL paging messages sent. By adopting the method, the paging message is directly sent to eRemote UE without a base station, and can be received through eRelay UE even if eRemote UE is not in the coverage range of the base station.

Before describing the technical scheme of the present application in detail, for convenience of understanding, a scene to which the embodiments of the present application are applied will be described. As shown in fig. 1, the method for transmitting paging messages provided by the present application may be applied to the network architecture shown in fig. 1. The network architecture comprises: base station 101, eRelay UE102,102 within the coverage area of base station 101, and a plurality of eRemote UE103,103 having sidelink connections with eRelay UE102,102. The eRemote UE103,103 has the characteristics of small volume, low power consumption, and the like, and is generally a wearable device, for example: smart watches, smart hands, etc. Communication between base stations 101 and eRelay UE102 may be via uplink and downlink. eRelay UE102 and eRemote UE103 may communicate through a sidelink communication technology, a communication link between eRelay UE and eRemote UE103 may be referred to as sidelink, and in addition, eRelay UE and eRemote UE may also communicate through a non-3GPP access technology, such as a bluetooth access technology, a wlan access technology, etc., which is not limited by the present application, and a sidelink communication between eRelay UE and eRemote UE is exemplified below. It should be noted that fig. 1 is only a schematic diagram of a network architecture to which the present application is applied, and in an actual deployment process, the number of devices in the network architecture is not limited to the number of devices shown in fig. 1.

As shown in fig. 2 in particular, the base station 101 may include: a communication interface 1011, a processor 1012, a memory 1013, and at least one communication bus 1014, the communication bus 101 for enabling connections and intercommunication between these devices; eRelay UE102 may include: a communication interface 1021, a processor 1022, a memory 1023, and at least one communication bus 1024, the communication bus 1024 for enabling connection and intercommunication among these devices; eRemote UE103 may include: a communication interface 1031, a processor 1032, a memory 1033, and at least one communication bus 1034, the communication bus 1034 being used to enable connections and intercommunication among these devices.

The communication interface 1011, the communication interface 1021, and the communication interface 1031 may be implemented by an antenna, and may be used for data interaction with an external network element, for example: communication interface 1011 of base station 101 may transmit and receive data packets or other information with eRelay UE and communication interface 1011 of base station 101 may also transmit and receive data packets or other information with eRemote UE103 (connection relationship between communication interface 1011 and communication interface 1031 is omitted in fig. 2); eRelay UE102 may send and receive data packets or other information with base station 101 or eRemote UE 103. For example: communication interface 1031 may send eRemote UE data and other information to communication interface 1021, where after communication interface 1021 receives the data and other information, it sends the data and other information to communication interface 1011 via a radio bearer between eRelay UE and the base station for processing by base station 101.

Processor 1012, processor 1022, processor 1032 may be a central processing unit (English: central Processing Unit, CPU), an Application SPECIFIC INTEGRATED Circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention. For example: one or more microprocessors (English: DIGITAL SINGNAL Processor, DSP), or one or more field programmable gate arrays (English: field Programmable GATE ARRAY, FPGA). Processor 1012, processor 1022, and processor 1032 have processing management functions, and specifically, processor 1012 in base station 101 may process received data or information sent by eRelay UE102,102, processor 1022 in eRelay UE102 may process received data or information sent by eRemote UE0103, and may also process data or information sent by base station 101. The processor 1032 in eRemote UE103 may process data or information generated by the Remote UE103 itself or process information or data transmitted by other devices.

Memory 1013, 1023, 1033, which may be volatile Memory (RAM) such as Random-Access Memory (english); or a non-volatile memory (non-volatile memory). Such as Read-Only Memory (ROM), flash Memory (flash Memory), hard disk (HARD DISK DRIVE, HDD) or Solid state disk (English: solid-STATE DRIVE, SSD); or a combination of memories of the above kind. Specifically, the memory 1013, the memory 1023, and the memory 1033 may store data or program codes supporting the data transmission method according to the embodiment of the present invention, so that the processor 1012, the processor 1022, and the processor 1032 execute the data transmission method provided by the embodiment of the present invention according to the data or program codes stored in the memory of the device where they are located.

The communication bus 1014, 1024, 1034 may be classified as an address bus, a data bus, a control bus, etc., and may be an industry standard architecture (english: industry Standard Architecture, ISA) bus, an external device interconnect (english: PERIPHERAL COMPONENT, PCI) bus, or an extended industry standard architecture (english: extended Industry Standard Architecture, EISA) bus, etc. The buses may be classified as address buses, data buses, control buses, etc. For ease of illustration, only one thick line is shown in fig. 2, but not only one bus or one type of bus.

In order to solve the problem that, in combination with the network architecture shown in fig. 1 and fig. 2, in the case that eRemote UE is out of coverage of a base station, a paging message sent by the base station cannot be received, an embodiment of the present application provides a method for transmitting a paging message, as shown in fig. 3, where the method includes:

301. the network equipment sends a first message to the first user equipment, wherein the first message is used for paging the second user equipment, and the first message at least comprises paging information of the second user equipment.

Wherein the paging information of the second user equipment comprises a second user equipment identity and core network domain information, which may be a circuit switched (Circuit Switching, CS) domain or a packet switched (PACKET SWITCHING, PS) domain.

The network device in this step may be a base station, and the first user devices in the embodiment of the present application may be eRelay UE, and the second user devices may be eRemote UE, where the second user devices described in the embodiment of the present application are all second user devices connected (link) with the first user devices.

When the base station needs to send data to eRemote UE in the rrc_idle state, a paging message needs to be sent to eRemote UE, triggering eRemote UE to enter the rrc_connected state. To prevent eRemote UE, which is not within its coverage, from failing to receive the paging message, the base station sends the paging message to eRelay UE and further sends the paging message to eRemote UE by eRelay UE.

Specifically, the first message sent by the base station to eRelay UE may be a broadcast message or a dedicated message sent to eRelay UE. When the first message is a broadcast message, the first message may include paging information of a plurality of eRemote UE of paging messages that the base station needs to send, where the paging information includes both the paging information of eRemote UE for which the sidelink is established with eRelay UE and the paging information of eRemote UE for which the sidelink is not established with eRelay UE; when the first message is a dedicated message sent to eRelay UE, the first message includes paging information of a plurality of eRemote UE that the base station needs to send paging messages, and these eRemote UE are eRemote UE that establish a sidelink with eRelay UE.

302. The first user equipment generates a second message according to the first message, the second message is used for paging the second user equipment, and the second paging message contains paging information of the second user equipment.

If the first message is a broadcast message, eRelay UE needs to screen out the paging information of eRemote UE with the sidelink from the first message, and generate a second message for each eRemote UE that is screened out, where the second message corresponding to each eRemote UE includes the paging information of eRemote UE. Or eRelay UE generates a second message, where the second message includes all the paging information of eRemote UE carried in the first message. Or eRelay UE does not make any screening, and directly forwards the first message to at least one eRemote UE with a sidelink.

If the first message is a dedicated message, eRelay UE needs to obtain the paging information of eRemote UE in the first message, and generate a second message for each eRemote UE according to the first message, where the second message corresponding to each eRemote UE includes the paging information of eRemote UE. Or eRelay UE generates a second message, where the second message includes all the eRemote UE paging information carried in the first message.

For example, assume that the first message received by eRelay UE1 is a broadcast message, where the first message carries paging information of 3 second user equipments, and the three second user equipments are eRemote UE1, eRemote UE2, eRemote UE3, respectively, where a sidelink connection exists between eRemote UE1, eRemote UE2 and eRelay UE1, and a sidelink connection exists between eRemote UE3 and eRelay UE 2. Then eRelay UE1 needs to generate second messages for eRemote UE1 and eRemote UE2 respectively, and the second message corresponding to eRemote UE1 includes the paging information of eRemote UE1, and the second message corresponding to eRemote UE2 includes the paging information of eRemote UE 2.

303. The first user equipment determines a monitoring time for the second user equipment to monitor the second message.

The method for determining the listening time by the first ue will be described in detail in the following embodiments, which are not repeated herein.

304. The first user equipment determines resources for sending the second message.

The method for determining the target resource by the first user equipment will be described in detail in the following embodiments, which are not repeated here.

It should be noted that, the embodiment of the present application does not limit the execution sequence among the step 302, the step 303, and the step 304.

305. The second user equipment determines a listening time for listening to the second message.

The method for determining the monitoring time by the second user equipment is the same as the method for determining the monitoring time by the first user equipment, except that the method for acquiring the parameter for determining the monitoring time by the second user equipment is different from the method for acquiring the information for determining the monitoring time by the first user equipment.

It should be noted that, the embodiment of the present application does not limit the execution sequence between the step 305 and the steps 302, 303 and 304, and the step 305 only needs to be executed before the step 306.

306. The first user equipment transmits a second message to the second user equipment at the listening time using the resource for transmitting the second message.

307. And the second user equipment monitors a second message sent by the first user equipment at the monitoring time.

It can be understood that the first ue and the second ue both determine the listening time for the second ue to listen to the second message, and then the first ue sends the second message at the listening time, and the second ue can listen to the second message at the listening time.

308. The second user equipment receives the second message when the second message is monitored.

After receiving the second message, the second ue also needs to notify the upper layer of its own device identifier, so that the upper layer triggers the second ue to initiate an RRC connection establishment procedure and switch to an rrc_connected state.

Compared with the method for transmitting paging messages, which is provided by the embodiment of the application, in the prior art, when the second user equipment is not in the signal coverage area of the base station and can not receive the paging messages, compared with the method for transmitting the paging messages, which is provided by the embodiment of the application, the base station can firstly transmit the first messages to the first user equipment, and then the first user equipment and the second user equipment determine the monitoring time of the second user equipment for monitoring the second messages, and the first user equipment can transmit the second messages for paging the second user equipment to the second user equipment in the monitoring time.

In addition, eRemote UE consumes higher power when directly receiving paging messages sent by the base station, while receiving paging messages through sidelink between eRemote UE and eRelay UE can reduce the power consumed.

In combination with the method flow shown in fig. 3, the first user equipment and the second user equipment need to determine the monitoring time of the second user equipment for monitoring the second message, and then the first user equipment sends the second message to the second user equipment through the sidelink at the monitoring time, so that the second user equipment can receive the second message at the monitoring time. The method for determining the listening time for the second user equipment to listen to the second message by the first user equipment and the second user equipment involved in the above steps 303 and 305 will be described in detail below.

Before the first ue and the second ue determine the listening time, parameters required for determining the listening time need to be acquired first, and based on this, in an implementation manner provided by the embodiment of the present invention, a method for acquiring parameters required for determining the listening time is described, as shown in fig. 4, where the method includes:

401. The second user equipment sends a third message to the first user equipment, wherein the third message carries information for determining the monitoring time.

Wherein the information used for determining the listening time in the third message may comprise a specific paging cycle (i.e. UE-SPECIFIC PAGING CYCLE of eRemote UE) of the second user equipment, a default paging cycle (default PAGING CYCLE) broadcasted by the base station, and at least one of the second user equipment identities.

It should be noted that, when determining the listening time, the first ue and the second ue both need to use a first identifier, where the first identifier may be a first ue identifier or a second ue identifier, and the first ue and the second ue may negotiate in advance whether the first identifier is the first ue identifier or the second ue identifier. It will be appreciated that when the first identity is the second user equipment identity, the second user equipment identity is included in the third message.

It is further noted that the third message may be a newly defined PC5-S message transmitted between eRemote UE and eRelay UE. For example, the third message may be designated as a page monitor request message (Paging Monitoring Request). In addition, the third message may be an existing message, for example, may be a Request message (direct_ Communicaiton _request) sent by eRemote UE for establishing Sidelink connection between eRemote UE and eRelay UE, that is, eRemote UE may carry information included in the third message described above when sending a Request message for establishing a sidelink connection to eRelay UE.

402. The first user equipment sends a seventh message to the second user equipment.

After receiving the third message, the first ue replies a seventh message to the second ue, and when the first identifier adopted by the first ue and the second ue for determining the listening time in negotiation is the first ue identifier, the seventh message needs to carry the first ue identifier.

In addition, the second ue may determine the listening time by nB (the number of subframes included in one paging cycle), a default paging cycle broadcasted by the network device, and some information known to the first ue, or the first ue may also determine the listening time by the resource pool configuration information and some information known to the first ue. Correspondingly, the seventh message may carry nB and at least one of default paging cycles of the system broadcast by the network device; or alternatively

The seventh message may carry resource pool configuration information configured by the network device for transmitting the second message, where the resource pool configuration information includes at least one of the following information:

The resource pool offset sl_offset is information indicating a starting position of the resource pool with respect to sfn=0, and SNF is a radio frame number;

The cycle length of the resource pool;

a bitmap for indicating a subframe in which the second message is transmitted;

frequency domain resource locations for transmitting the second message.

In addition, the seventh message may further carry an offset po_offset configured by the first ue for the second ue to receive the second message, where po_offset is an offset configured by the first ue for the second ue to determine a subframe position of the second ue for monitoring the second message according to the second ue identifier and the paging cycle.

It is further noted that the seventh message may be a newly defined PC5-S message transmitted between eRemote UE and eRemote UE. For example, the seventh message may be designated as a page monitor reply message (Paging Monitoring Reponse). In addition, the seventh message may be an existing message, for example, may be a response message (direct_ Communicaiton _ Reponse) sent by eRelay UE to establish Sidelink connection between eRemote UE and eRelay UE, that is, eRemote UE may carry information included in the seventh message described above when sending a response message to eRelay UE to establish a sidelink connection.

In another possible implementation manner, the seventh message may also be a message periodically broadcast by the second ue, where the broadcast message may be a newly defined broadcast message sent on a sidelink between the first ue and the second ue, or may be an existing sidelink main information block message (Master Information Block-sidelink), and the first user may receive the broadcast message through the sidelink, and further obtain information carried in the broadcast message.

In another possible implementation manner, the first UE may further obtain the second UE identifier and information of the second UE-SPECIFIC PAGING CYCLE for determining the listening time from the network device, and the network side device may send a fourth message to the first UE, where the fourth message carries information of the second UE-SPECIFIC PAGING CYCLE for determining the listening time.

Wherein the information for determining the listening time comprises at least one of a second user equipment identity, a system default paging cycle, and a specific paging cycle of the second user equipment.

It should be noted that, the base station may send the fourth message carrying the UE-SPECIFIC PAGING CYCLE of eRemote UE to eRelay UE separately in the form of a dedicated message, or may send the UE-SPECIFIC PAGING CYCLE of eRemote UE to eRelay UE during paging eRemote UE, in this case, the network side device includes an MME and a base station, first the MME sends the paging message carrying the UE-SPECIFIC PAGING CYCLE of eRemote UE to the base station, and after receiving the paging message, the base station sends the paging message carrying the UE-SPECIFIC PAGING CYCLE of eRemote UE to eRelay UE, where the fourth message may be the first message described in the embodiment shown in fig. 3, that is, the first message may further include a specific paging cycle of the second user equipment.

Based on the information for determining the listening time acquired by the first ue and the second ue in the above steps, the first ue and the second ue may determine the listening time of the second ue for listening to the second message, and before determining the listening time of the second ue for listening to the second message, the first ue and the second ue need to determine a first identifier for determining the listening time and a first paging cycle for determining the first listening time.

The first identifier is a first user equipment identifier or a second user equipment identifier, that is, a eRelay UE device identifier or a eRemote UE device identifier. The device identity may specifically be an international mobile subscriber identity (International Mobile Subscriber Identity, IMSI), S-TMSI, IMSI mod 1024 of the user equipment, or other identity that may represent the identity of the user equipment.

The first paging cycle may be the specific paging cycle of the second user equipment or the smaller of the specific paging cycle of the second user equipment and the default paging cycle of the system broadcast by the network equipment, i.e. the first paging cycle may be the smaller of the UE-SPECIFIC PAGING CYCLE of eRemote UE or the UE-SPECIFIC PAGING CYCLE of eRemote UE and the default PAGING CYCLE broadcast by the base station.

It should be noted that, the first identifiers determined by the first ue and the second ue are the same, and the first paging periods determined by the first ue and the second ue are also the same, and after the first identifiers and the first paging periods are determined by the first ue and the second ue, the listening time can be determined according to the information for determining the listening time.

The method for determining the monitoring time by the first user equipment and the second user equipment is the same, and the first user equipment is taken as an example for description.

The method comprises the following steps:

and the first user equipment determines the position of the wireless frame and the position of the subframe monitored by the second user equipment in the sidelink according to the first identifier, the first paging cycle and the nB.

The specific determination method comprises the following steps: firstly, the first user equipment determines the position of a monitored radio frame and the position of a subframe when the second user equipment monitors a downlink according to a first identifier, a first paging cycle and nB, and then determines the position of the monitored radio frame and the position of the subframe when the second user equipment monitors the downlink according to the position of the monitored radio frame and the position of the monitored subframe when the second user equipment monitors the downlink.

Specifically, the location of the radio frame and the location of the subframe monitored by eRemote UE when the Uu port monitors the downlink may be determined according to the following formula.

Equation 1: SFN mod t= (tdiv N) × (ue_id mod N)

Equation 2: i_s=floor (ue_id/N) mod Ns

The location of the monitored radio frame when eRemote UE listens to the downlink can be determined by solving the SFN according to the above formula 1, i_s can be obtained according to the formula 2, and then the location of the monitored subframe when eRemote UE listens to the downlink can be determined according to i_s in combination with table 1 or table 2.

For a frequency division duplex (Frequency Division Duplexing, FDD) system, the possible subframe location is 0,4,5,9, and the location of the subframe to be monitored when eRemote UE monitors the downlink can be determined according to i_s and table 1.

TABLE 1

For a time division duplex (Time Division Duplexing, TDD) system, the possible subframe locations are 0,1,5,6, and the locations of the subframes where eRemote UE listens to the downlink can be determined from i_s and table 2.

TABLE 2

After determining eRemote UE the position of the monitored radio frame and the position of the subframe when the downlink is monitored through the above process, the position of the monitored radio frame and the position of the subframe in the sidelink can be further determined eRemote UE, and the determining method comprises the following two implementation modes:

The implementation mode is as follows: and determining eRemote UE the positions of the wireless frames and the sub-frames monitored in the sidelink according to the corresponding relation between the positions of the wireless frames and the sub-frames monitored in the downlink monitored by the eRemote UE and the positions of the wireless frames and the sub-frames monitored in the sidelink in eRemote UE.

For FDD systems, eRemote UE monitors the downlink at the same positions of the radio frames and subframes as eRemote UE monitors in the sidelink, as shown in fig. 5, eRemote UE monitors in the sidelink in the radio frames a and X, and the subframes to be monitored are the subframes represented by the shaded portions in the radio frames a and X.

For a TDD system, the position of a radio frame monitored by eRemote UE when monitoring a downlink is the same as the position of a radio frame monitored by eRemote UE at a sidelink, according to different TDD configurations, there is a different correspondence between the position of a subframe monitored by eRemote UE when monitoring a downlink and the position of a subframe monitored by eRemote UE at a sidelink, wherein one possible correspondence is shown in table 3, uu PO in table 3 represents the position of a subframe monitored by eRemote UE when monitoring a downlink, and SL PO represents the position of a subframe monitored by eRemote UE at a sidelink.

TABLE 3 Table 3

The implementation mode II is as follows:

For the FDD system, the position of the subframe monitored by the second user equipment in the sidelink is the position of the monitored subframe when the second user equipment monitors the downlink, and the first offset is a positive integer greater than or equal to 0. The first offset may be configured by the first ue, or may be configured by the base station, or be a preset value.

For example, eRemote UE listens to the downlink in the radio frame with sfn=10, the subframe number Subfrmae #0, and if the first offset value is 20, eRemote UEsidelink listens to the subframe with sfn=30, the subframe number Subfrmae #0.

For the TDD system, after the second user equipment adds a second offset to the position of the monitored subframe when the second user equipment monitors the downlink, the first subframe in the resource pool can be used for transmitting the second message, and the second offset is a positive integer greater than or equal to 0. The second offset may be configured by the first ue, or may be configured by the base station, or be a preset value.

For example, eRemote UE listens to the downlink at the radio frame position sfn=10, the subframe number Subfrmae #0, and if the second offset value is 25, eRemote UEsidelink listens to the radio frame at sfn=30, the subframe number Subfrmae #5.

The second method is as follows:

1. the first user equipment determines the number N of resource pool periods contained in one paging period of the second user equipment and the number M of subframes used for sending the second message in each resource pool period according to the resource pool configuration information, the first identifier and the first paging period.

Specifically, according to the period length of the resource pool, the number N, n=paging period length/period length of the resource pool period included in one paging period can be determined eRemote UE, and further, the number of the resource pool in one paging period of eRemote UE is determined to be 0,1,2 and … N-1, respectively. For example, as shown in fig. 6, if the offset of the resource pool is 10ms, the length of the paging cycle is 320ms, and the cycle length of the resource pool is 20ms, n=16, and the numbers of the resource pools in the paging cycle are 0,1,2 …, respectively.

In addition, according to the bitmap of the subframe used for indicating to transmit the second message contained in the configuration information of the resource pool, the number M of subframes used for transmitting the second message in each resource pool period can be determined, and then the index numbers corresponding to the subframes available for transmitting the second message in each resource pool period are respectively 0,1,2 … M-1. For example, if the bitmap of the subframe for transmitting the second message in one resource pool period is (0010000000,0000000100), it may be determined that m=2, and the index numbers corresponding to the subframes for transmitting the second message in one resource pool period are 0,1, respectively. As shown in fig. 6, the subframe for transmitting the second message determined according to the bitmap is the subframe corresponding to the shaded area, that is, in the resource period 1, there are two subframes for transmitting the second message, the first subframe for transmitting the second message is the subframe 2in the first frame, then the index number corresponding to the subframe is 0, the second subframe for transmitting the second message is the subframe 7 in the first frame, and then the index number corresponding to the subframe is 1.

2. The first user equipment determines that in a first paging cycle, the second user equipment needs to monitor a resource pool cycle number of the second message, wherein the resource pool cycle number is the first identifier mod N.

Where N is the number of resource pool periods that eRemote UE determined in the previous step contains in one paging cycle.

3. The first user equipment determines that in a resource pool period, the second user equipment needs to monitor an index number corresponding to a subframe of the second message, wherein the index number of the subframe is floor (first identifier/N) mod M.

4. And the first user equipment determines the subframe position monitored by the second user equipment in the sidelink according to the resource pool period number determined in the step 2 and the subframe index number determined in the step 3.

After the resource pool period number and the subframe number are determined, the subframe position corresponding to the subframe number can be determined from the resource pool period corresponding to the resource pool period number, and the subframe position is the subframe position monitored by the second user equipment in the sidelink.

And a third method:

The first ue determines a third offset po_offset according to the first identifier and the first paging cycle, and then the first ue determines a frame number and a subframe number of the second message monitored by the second ue at the sidelink according to [ frame number×10+subframe number+sl_offset ] module (first paging cycle) =po_offset, where sl_offset is the offset of the resource pool.

It should be noted that, in the formula [ frame number×10+subframe number+sl_offset ] module (first paging cycle) =po_offset, sl_offset, first paging cycle, and po_offset are known, and the frame number and subframe number satisfying the formula are the frame number and subframe number of the second ue listening to the second message in the sidelink.

For example, as shown in fig. 7, if the resource pool period is 20ms, the offset of the resource pool is 10ms, and the bitmap of the uplink subframe position for transmitting the second message in one resource pool period is (0010000000,0000000000). Assume that there are two eRemote UE under one eRelay UE with which a connection (link) relationship is established or a side-link connection is established, and that the paging cycle of both eRemote UE is 320ms. If the subframe position allocated for eRelay UE to eRemote UE1 in each paging cycle is subframe 0 shown in fig. 7 and the subframe position allocated for eRemote UE2 by the erelay UE in each paging cycle is subframe 1 shown in fig. 7, eRelay UE requires that the po_offset configured for both eRemote UE be 2 and 22, respectively.

For the embodiment of the application, the first user equipment and the second user equipment can determine the monitoring time of the second user equipment for monitoring the second message, and then the first user equipment sends the second message in the monitoring time, and the second user equipment can receive the second message in the monitoring time, so that the second user equipment does not need to monitor the second message on a downlink, the power consumption is reduced, the second user equipment does not need to monitor the sidelink all the time, and only needs to wake up in the monitoring time to receive the second message.

Before the first ue sends the second message to the second ue, it is necessary to determine not only the listening time of the second ue for listening to the second message, but also the resources for sending the second message, and in another implementation manner of the embodiment of the present invention, the method for determining, by the first ue, the resources for sending the second message in step 204 is described.

Method 1:

After the first user equipment receives the first message sent by the network equipment, if the first message is determined to contain the eRemote UE equipment identifier which establishes the sidelink connection with the first user equipment, whether the first user equipment is in the RRC_IDLE state or the RRC_CONNECTED state, the first user equipment determines a subframe in which the second user equipment monitors the second message in the sidelink, and further combines the frequency domain resource position for transmitting the second message contained in the resource pool configuration information, and randomly selects the frequency domain resource for transmitting the second message in the determined subframe in an equal probability mode.

Method 2:

After the first user equipment receives the first message sent by the network equipment, if the first message contains eRemote UE equipment identification which establishes a sidelink connection with the first user equipment, if the first user equipment is in an RRC_IDLE state, the first user equipment determines a subframe in which the second user equipment monitors the second message in the sidelink, and further combines the frequency domain resource position which is contained in the resource pool configuration information and is used for transmitting the second message, and in the determined subframe, frequency domain resources which are used for transmitting the second message are randomly selected in an equiprobable mode.

When the first user equipment receives the first message sent by the network equipment, if the first message contains eRemote UE equipment identification which establishes a sidelink connection with the first user equipment, if the first user equipment is in an RRC_CONNECTED state, the first user equipment sends a fifth message to the network equipment, the fifth message is used for requesting to acquire resources for sending the second message, after the network equipment receives the fifth message, the network equipment returns a sixth message to the first user equipment, and the sixth message contains resource information or resource pool information which is allocated by the network equipment for the first user equipment and is used for sending the second message.

Wherein the fifth message contains at least one of the following information:

a request destination for indicating that the purpose of the fifth message is to acquire a resource for transmitting the second message;

The time for sending the second message may specifically be a frame number and a subframe number used by the first user equipment to send the second message;

The number of bits contained in the second message;

The number of paging information included in the second message corresponds to one paging information for each second user equipment, and each paging information includes a second user equipment identifier and a core network domain information, where the core network domain information is a circuit switched (Circuit Switching, CS) domain or a packet switched (PACKET SWITCHING, PS) domain.

Method 3:

If the first user equipment is in RRC_IDLE state, the network equipment sends a first message for paging the second user equipment to the first user equipment in a broadcast mode, if the first message contains a eRemote UE equipment identifier which establishes a sidelink connection with the first user equipment, the first user equipment determines that the second user equipment monitors a subframe of the second message in the sidelink, and further combines the frequency domain resource position for transmitting the second message contained in the resource pool configuration information, and in the determined subframe, frequency domain resources for transmitting the second message are randomly selected in an equal probability mode.

If the first user equipment is in the rrc_connected state, the network equipment sends a first message for paging the second user equipment to the first user equipment in a dedicated message manner, where the first message also carries a frequency domain resource location for transmitting the second resource, and then after determining that the second user equipment monitors a subframe of the second message in the sidelink, the first user equipment can send the second message to the second user equipment in the determined subframe by using the frequency domain resource indicated by the frequency domain resource location carried in the first message.

Method 4:

When the network device needs to send the first message to the first user device, if the first user device is in the rrc_idle state or the ecm_idle state, the network device will send a paging message to the first user device first, so that the first user device transitions to the rrc_connected state ecm_connected state. When the first user equipment is in the rrc_connected state or the ecm_connected state, the network equipment sends a first message for paging the second user equipment to the first user equipment in a dedicated message form, the first message also carries a frequency domain resource position for transmitting the second resource, and then the first user equipment can send the second message to the second user equipment in the determined subframe by using the frequency domain resource indicated by the frequency domain resource position carried in the first message after determining that the second user equipment monitors the subframe of the second message in the sidelink.

Specifically, when the MME needs to send a paging message to eRemote UE having a sidelink connection with the eRelay UE through eRelay UE, the MME will first determine the state of eRelay UE, and if it is determined that the eRelay UE is in rrc_idle state or ecm_idle state, the MME will send a paging message to the eRelay UE to trigger eRelay UE to perform state transition. After the MME determines eRelay UE that the ecm_connected and rrc_connected states are entered, the MME sends a paging message for paging eRemote UE to the base station, and then the base station sends a first message for paging eRemote UE to eRelay UE through dedicated signaling, where the first message carries the device identifier of eRemote UE and a frequency domain resource location for sending a second message. eRelay UE after determining eRemote UE the listening time for listening to the second message, the second message may be sent to eRemote UE at the listening time using the frequency domain resources indicated by the frequency domain resource location carried in the first message.

Method 5:

When the first ue receives the first message sent by the network device and used for paging eRemote UE, if it is determined that the first message includes the device identifier of eRemote UE that the sidelink connection is established with itself, and the first ue is in the rrc_idle state, the first ue may trigger the RRC connection establishment procedure, so as to switch to the rrc_connected state. After the rrc_connected state is shifted, the first user equipment sends a fifth message to the network equipment, where the fifth message is used to request to obtain resources for sending the second message, and after the network equipment receives the fifth message, the network equipment returns a sixth message to the first user equipment, where the sixth message includes resource information or resource pool information allocated by the network equipment for the first user equipment and used to send the second message.

Wherein the fifth message contains at least one of the following information:

The number of bits contained in the second message;

It may be understood that, after the first user equipment and the second user equipment determine the listening time of the second user equipment for listening to the second message, and the first user equipment determines the frequency domain resource for transmitting the second message, the first user equipment may transmit the paging message for paging the second user equipment to the second user equipment through the sidelink, and in order to implement transmitting the paging message on the sidelink, an embodiment of the present application provides a protocol stack, as shown in fig. 8.

Wherein the base station may transmit the first message through Uu port of the RRC layer, i.e., the base station may send the first message to eRelay UE through paging control channel (Paging Control Channel, PCCH) and paging channel (Paging Control Channel, PCH) of the air interface.

After the RRC layer of eRelay UE receives the first message sent by the base station through the Uu port, if it is determined that the first message includes the device identifier of eRemote UE that establishes a sidelink connection with itself, the RRC layer of eRelay UE generates a second message including the device identifier of eRemote UE, and sends the second message to the RLC layer of PC 5. The RLC layer of the PC5 then sends the second message to the medium access Control (MEDIA ACCESS Control, MAC) layer of the PC5 directly over a defined separate dedicated Control channel (Stand-Alone Dedicated Control Channel, SPCCH) for transmission of the second message, without any processing of the second message, in a transparent transmission mode. The transparent transmission mode is still adopted at the MAC layer of the PC5, and the MAC layer of the PC5 does not perform any processing on the second message, and directly transmits the second message to the physical (PHYSICAL LAYER, PHY) layer of the PC5 through the transmission channel SL-PCH for transmitting the second message.

ERemote UE, after receiving the second message, transmits the second message to the MAC layer of PC5 through a transmission channel SL-PCH for transmitting the second message, and then the MAC layer of PC5 transfers the message to the RRC layer through the SPCCH. If the second message contains the eRemote UE device identification, the RRC layer transmits the eRemote UE device identification to the upper protocol layer

In one possible implementation, the protocol stack illustrated in fig. 8 may also be implemented as illustrated in fig. 9.

An embodiment of the present application also provides another protocol stack, as shown in fig. 10.

The base station may transmit the first message through a Uu port of the PDCP layer, and specifically, the base station may send a dedicated message to eRelay UE through DCCH and DCH of an air port: an RRC connection reconfiguration (RRC Connection Reconfiguration) message, the RRC connection reconfiguration message including the first message.

After eRelay UE receives the first message, the subsequent process of transmitting the message eRelay UE and eRemote UE is the same as that described in the corresponding embodiment of fig. 8, and will not be repeated here.

In a possible implementation, the protocol stack configuration shown in fig. 10 may be replaced by the configuration shown in fig. 11.

It should be noted that, in the embodiment of the present application, the second message generated by the first ue through the RRC layer is applicable to any short-range connection technology, that is, the first ue and the second ue may transmit the second message not only through sidelink, but also through a wireless local area network (Wireless Local Area Networks, WLAN) or other manners.

The scheme provided by the embodiment of the application is mainly introduced from the angles of the first user equipment and the second user equipment. It will be appreciated that the first user device and the second user device comprise corresponding hardware structures and/or software modules that perform the respective functions. Those of skill in the art will readily appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as hardware or combinations of hardware and computer software. Whether a function is implemented as hardware or computer software driven hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

The embodiment of the application can divide the functional modules of the first user equipment and the second user equipment according to the method example, for example, each functional module can be divided corresponding to each function, or two or more functions can be integrated in one processing module. The integrated modules may be implemented in hardware or in software functional modules. It should be noted that, in the embodiment of the present application, the division of the modules is schematic, only one logic function is divided, and another division manner may be implemented in actual implementation.

In the case of dividing each functional module by adopting corresponding each function, the embodiment of the application also provides a device for transmitting paging messages, which can be implemented as the first user equipment in the above embodiment. As shown in fig. 12, fig. 12 shows a schematic diagram of one possible configuration of the first user equipment (eRelay UE) involved in the above embodiment. The first user equipment comprises: the device comprises a receiving module 121, a generating module 122, a determining module 123, an obtaining module 124, a sending module 125 and a converting module 126.

The receiving module 121 is configured to support the first user equipment to receive a first message sent by the network equipment in step 301 in fig. 3, and a third message sent by the second user equipment in step 401 in fig. 4; a generating module 122, configured to support the first user equipment to perform step 302 in fig. 3; a determining module 123, configured to support the first user equipment to perform step 304 in fig. 3; an obtaining module 124, configured to support the first user equipment to perform step 305 in fig. 3; a sending module 125, configured to support the first user equipment to perform step 306 in fig. 3, and step 402 in fig. 4; the switching module 126 is configured to support the first ue to trigger the RRC establishment procedure and switch to the rrc_ CONNRECTED state.

All relevant contents of each step related to the above method embodiment may be referred to the functional description of the corresponding functional module, which is not described herein.

In the case of using the integrated units, the generating module 122, the determining module 123, the obtaining module 124, and the converting module 126 shown in fig. 12 may be integrated in the processor 1022 shown in fig. 2, so that the processor 1022 may perform specific functions of the generating module 122, the determining module 123, the obtaining module 124, and the converting module 126, and the receiving module 121 and the transmitting module 125 may be integrated in the communication interface 1021 shown in fig. 2, so that the communication interface 1021 may perform specific functions of the receiving module 121 and the transmitting module 125.

In the case of dividing the respective functional modules by the respective functions, the embodiment of the present application also provides another apparatus for transmitting a paging message, which may be implemented as the second user equipment in the above embodiment. As shown in fig. 13, fig. 13 shows a schematic diagram of one possible configuration of the second user equipment (eRemote UE) involved in the above embodiment. The second user equipment includes: the device comprises a determining module 131, a monitoring module 132, a sending module 133 and a receiving module 134.

Wherein, the determining module 131 is configured to support the second user equipment to perform step 305 in fig. 3; a listening module 132, configured to support the second ue to perform step 307 in fig. 3; a sending module 133, configured to support the second user equipment to perform step 401 in fig. 4; the receiving module 134 is configured to support the second ue to perform the second message sent by the first ue in step 306 in fig. 3, and the seventh message sent by the first ue in fig. 4.

In the case of using the integrated unit, it should be noted that the determining module 131 and the listening module 132 shown in fig. 13 may be integrated in the processor 1032 shown in fig. 2, so that the processor 1032 performs the specific functions of the determining module 131 and the listening module 132, the transmitting module 133, and the receiving module 134 may be integrated in the communication interface 1031 shown in fig. 2, so that the communication interface 1031 performs the specific functions of the transmitting module 133 and the receiving module 134.

The embodiment of the application also provides a data transmission system, which can comprise the first user equipment, the second user equipment and the network equipment.

An embodiment of the present application further provides a computer storage medium storing computer software instructions for the first user device, where the computer storage medium includes a program designed to execute the steps executed by the first user device in the foregoing embodiment.

The present application provides a computer storage medium for storing computer software instructions for the second ue, which includes a program designed to execute the steps executed by the first ue in the above embodiment.

The steps of a method or algorithm described in connection with the present disclosure may be embodied in hardware, or may be embodied in software instructions executed by a processor. The software instructions may be comprised of corresponding software modules that may be stored in random access Memory (Random Access Memory, RAM), flash Memory, read Only Memory (ROM), erasable programmable Read Only Memory (Erasable Programmable ROM), electrically Erasable Programmable Read Only Memory (EEPROM), registers, hard disk, a removable disk, a compact disk Read Only Memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. In addition, the ASIC may be located in a core network interface device. The processor and the storage medium may reside as discrete components in a core network interface device.

In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, or may be in electrical or other forms.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network devices. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each functional unit may exist independently, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in hardware plus software functional units.

From the above description of embodiments, it will be clear to a person skilled in the art that the present application may be implemented by means of software plus necessary general purpose hardware, but of course also by means of hardware, the former being in many cases a preferred embodiment. Based on such understanding, the technical solution of the present application may be embodied essentially or in a part contributing to the prior art in the form of a software product stored in a readable storage medium, such as a floppy disk, a hard disk, or an optical disk of a computer, etc., including several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method according to the embodiments of the present application.

The foregoing is merely illustrative of specific embodiments of the present application, and the present application is not limited to these embodiments, but is intended to cover modifications and alternatives within the technical scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of transmitting a paging message, comprising:

establishing a side uplink connection between a first user equipment and a second user equipment;

The first user equipment receives a first message sent by network equipment, wherein the first message is used for paging the second user equipment, and the first message comprises paging information of the second user equipment;

the first user equipment sends a second message to the second user equipment, wherein the second message comprises paging information of the second user equipment; wherein,

The first user equipment is in an RRC idle state, receives a first message through a paging channel, wherein the first message is a broadcast message, and generates a second message when the paging information of the second user equipment is included in the first message; or alternatively

The first user equipment is in an RRC connection state, and the first message is contained in an RRC connection reconfiguration message;

the paging information of the second user equipment includes an equipment identification of the second user equipment.

2. The method of transmitting paging messages according to claim 1, further comprising, before said first user device receives a first message sent by a network device:

The first user equipment receives a third message sent by the second user equipment, wherein the third message comprises a specific paging cycle (UE-SPECIFIC PAGING CYCLE) of the second user equipment and equipment identification of the second user equipment.

3. The method of claim 1 or 2, the device identity of the second user equipment being an S-TMSI of the second user equipment.

4. The method according to claim 1 or 2, characterized in that the method further comprises:

The first user equipment generates the second message according to the first message, wherein the second message is used for paging a second user equipment, and the second message contains paging information of the second user equipment;

the first user equipment receives resource pool configuration information configured by the network equipment and used for transmitting the second message;

The first user equipment determines the number N of resource pool periods contained in one first paging period of the second user equipment and the number M of subframes used for sending the second message in each resource pool period according to the resource pool configuration information, the first identifier and the first paging period; the first identifier is a first user equipment identifier or a second user equipment identifier, and the first paging cycle is a specific paging cycle or the smaller one of the specific paging cycle and a default paging cycle of the system;

The first user equipment determines that the second user equipment needs to monitor a resource pool period number of the second message in a first paging period, wherein the resource pool period number is the first identifier mod N;

the first user equipment determines that the second user equipment needs to monitor the subframe number of the second message in a resource pool period, wherein the subframe number is floor (first identifier/N) mod M;

The first user equipment determines the monitoring time of the second user equipment according to the resource pool period number and the subframe number, wherein the monitoring time of the second user equipment is the subframe position monitored by the second user equipment in a sidelink;

the first user equipment acquires resources for sending the second message;

And the first user equipment sends the second message to the second user equipment by using the resource for sending the second message in the monitoring time.

5. The method of transmitting paging messages as claimed in claim 4, further comprising:

The first user equipment receives a third message sent by the second user equipment, wherein the third message carries information for determining the monitoring time; or alternatively

And the first user equipment receives a fourth message sent by the network equipment, wherein the fourth message carries information for determining the monitoring time.

6. The method of transmitting paging messages according to claim 5, wherein said information for determining said listening time comprises a second user equipment identification, a specific paging cycle of said second user equipment, at least one of a system default paging cycle.

7. The method of transmitting a paging message as claimed in claim 6, further comprising:

The first user equipment determines a first identifier for determining the monitoring time, wherein the first identifier is a first user equipment identifier or a second user equipment identifier;

The first user equipment determines a first paging cycle for determining the listening time, the first paging cycle being the specific paging cycle or the smaller of the specific paging cycle and the default paging cycle of the system.

8. The method of transmitting paging messages according to any one of claims 5 to 7, wherein the resource pool configuration information comprises at least one of:

A resource pool offset;

The cycle length of the resource pool;

a bitmap for indicating a subframe in which the second message is transmitted;

frequency domain resource locations for transmitting the second message.

9. The method according to claim 1, wherein if the first ue is in rrc_idle state, after the first ue receives the first message sent by the network device, the method further comprises:

The first user equipment triggers an RRC connection establishment process and transitions to an RRC_ CONNRECTED state.

10. The method of transmitting paging messages as claimed in claim 4, wherein said first user equipment obtaining resources for transmitting said second message comprises:

The first user equipment sends a fifth message to the network equipment, wherein the fifth message is used for requesting to acquire resources for sending the second message;

The first user equipment receives a sixth message sent by the network equipment, wherein the sixth message comprises resource information or resource pool information which is distributed by the network equipment for the first user equipment and is used for sending the second message.

11. The method of transmitting paging messages as claimed in claim 10, wherein the fifth message comprises at least one of the following information:

time of sending the second message;

The number of paging information contained in the second message, wherein each second user equipment corresponds to one paging information;

the number of bits contained in the second message.

12. The method of transmitting paging messages as claimed in claim 4, wherein said first user equipment obtaining resources for transmitting said second message comprises:

the first user equipment acquires resources for sending the second message from the first message, wherein the first message contains resource information or resource pool information which is distributed by the network equipment for the first user equipment and is used for sending the second message.

13. The method of transmitting paging messages as claimed in claim 4, wherein said first user equipment receives a first message sent by a network device; the first user equipment generates a second message according to the first message, and the second message comprises:

The radio resource control layer of the first user equipment receives the first message and generates the second message according to the first message.

14. An apparatus for transmitting a paging message, the apparatus being adapted for use in a first user device, the apparatus comprising:

a memory for storing information including program instructions;

the communication interface is used for receiving a first message sent by the network equipment, wherein the first message is used for paging the second user equipment, and the first message at least comprises paging information of the second user equipment;

A processor coupled to said memory and said communication interface for controlling execution of program instructions, in particular for controlling establishment of a sidelink connection between said first user equipment and said second user equipment; and the communication interface is further used for controlling the communication interface to send a second message to the second user equipment, wherein the second message comprises paging information of the second user equipment; wherein,

15. The apparatus for transmitting a paging message as claimed in claim 14, wherein,

The communication interface is further configured to receive a third message sent by the second user equipment before receiving the first message sent by the network equipment, where the third message includes a specific paging cycle (UE-SPECIFIC PAGING CYCLE) of the second user equipment and an equipment identifier of the second user equipment; wherein the equipment identifier of the second user equipment is the S-TMSI of the second user equipment.

16. The apparatus for transmitting paging messages as claimed in claim 14 or 15, wherein,

The communication interface is further configured to receive resource pool configuration information configured by the network device and used for transmitting a second message;

The processor is further configured to generate, according to the first message received by the communication interface, the second message, where the second message is used to page the second user equipment, and the second message includes paging information of the second user equipment; determining the number N of resource pool periods contained in one first paging period of the second user equipment and the number M of subframes used for sending the second message in each resource pool period according to the resource pool configuration information, the first identifier and the first paging period; determining that the second user equipment needs to monitor a resource pool period number of the second message in a first paging period, wherein the resource pool period number is the first identifier mod N; determining that the second user equipment needs to monitor the subframe number of the second message in a resource pool period, wherein the subframe number is floor (first identifier/N) mod M; determining the monitoring time of the second user equipment according to the resource pool period number and the subframe number, wherein the monitoring time of the second user equipment is the subframe position monitored by the second user equipment in a sidelink; the first identifier is a first user equipment identifier or a second user equipment identifier, and the first paging cycle is a specific paging cycle or the smaller one of the specific paging cycle and a default paging cycle of the system;

The processor is further configured to control the communication interface to acquire a resource for sending the second message;

And the processor is further configured to control the communication interface to send the second message generated by the processor to the second user equipment at the listening time by using a resource for sending the second message.

17. The apparatus for transmitting a paging message as claimed in claim 16, wherein,

The communication interface is further configured to receive a third message sent by the second user equipment, where the third message carries information for determining the listening time; or receiving a fourth message sent by the network equipment, wherein the fourth message carries information for determining the monitoring time; wherein the information for determining the listening time includes a second user equipment identity, a specific paging cycle of the second user equipment, and at least one of default paging cycles of a system.

18. The apparatus for transmitting a paging message as claimed in claim 17, wherein,

The processor is further configured to determine a first identifier of the listening time, where the first identifier is a first user equipment identifier or the second user equipment identifier; a first paging cycle for determining the listening time is determined, the first paging cycle being the particular paging cycle or the smaller of the particular paging cycle and the default paging cycle of the system.

19. The apparatus for transmitting paging messages as claimed in claim 16, wherein said resource pool configuration information comprises at least one of:

A resource pool offset;

The cycle length of the resource pool;

a bitmap for indicating a subframe in which the second message is transmitted;

frequency domain resource locations for transmitting the second message.

20. The apparatus for transmitting a paging message as claimed in claim 14, wherein,

The processor is further configured to trigger an RRC connection establishment procedure to transition to an rrc_ CONNRECTED state.

21. The apparatus for transmitting a paging message as claimed in claim 19, wherein,

The communication interface is further configured to send a fifth message to the network device, where the fifth message is used to request to obtain a resource for sending the second message; receiving a sixth message sent by the network device, wherein the sixth message comprises resource information or resource pool information which is distributed by the network device for the first user device and used for sending the second message;

Wherein the fifth message includes at least one of the following information:

time of sending the second message;

the number of bits contained in the second message.

22. The apparatus for transmitting a paging message as claimed in claim 19, wherein,

The communication interface is further configured to obtain, from the first message, a resource for sending the second message, where the first message includes resource information or resource pool information allocated by the network device for the first user device and used for sending the second message.

23. The apparatus for transmitting a paging message as claimed in claim 19, wherein,

The communication interface is further configured to receive the first message through a radio resource control layer;

The processor is further configured to generate the second message through a radio resource control layer according to the first message.