Communication method and communication device

Abstract

The present application provides a communication method and a communication device, which can help to achieve the alignment of the RRC state of the first terminal device among a network device, a first terminal device, and a second terminal device. The method includes: receiving first indication information, the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device; monitoring the paging message sent by the network device for the first terminal device. The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. The present application can be applied to wireless communication systems, such as D2D communication systems, V2X communication systems, etc.

Description

Technical Field

[0001] The present application relates to the field of communications, and more specifically, to a communication method and a communication device. Background Art

[0002] With the development of wireless multimedia services, people's demand for high data rates and user experience is growing, which puts higher requirements on the system capacity and coverage of traditional cellular networks. In addition, the popularity of applications such as social networks, close-range data sharing, and local advertising has led to an increasing demand for people to understand and communicate with people or things of interest nearby, namely proximity services. However, traditional cell-based cellular networks have obvious limitations in supporting high data rates and proximity services. In this demand context, devices in the communication system (such as terminal devices and terminal devices) can communicate with each other. Communication between devices can reduce the burden on cellular networks, reduce battery power consumption of user devices, increase data rates, and improve the robustness of network infrastructure, which can well meet the requirements of the above-mentioned high data rate services and proximity services. Communication between devices may be, for example, device-to-device (D2D) communication, vehicle to everything (V2X) communication, etc., wherein V2X communication may be, for example, vehicle to vehicle (V2V), vehicle to pedestrian (V2P), vehicle to roadside infrastructure (vehicle to infrastructure) communication, etc., without limitation.

[0003] Device-to-device communication allows multiple user devices to perform direct discovery / direct communication with or without network infrastructure. In some scenarios, these devices may include relay node UEs (or relay UEs), and remote UEs at the edge of or outside the coverage of the cellular network can perform cellular communication with the network through the relay node UE, or devices can communicate through the relay UE.

[0004] Remote UE can support three RRC states: idle, inactive, and connected. There are some possible scenarios where the remote UE and the network device do not match the RRC state of the remote UE. For example, the network device believes that the remote UE is in an idle or inactive state, while the remote UE believes that it is currently in a connected state. At this time, how the network device, remote UE, and relay UE align the RRC state of the remote is an urgent problem to be solved. Summary of the invention

[0005] The present application provides a communication method and a communication device, which can help to achieve the alignment of the RRC state of the first terminal device among a network device, a first terminal device, and a second terminal device.

[0006] In a first aspect, a communication method is provided, which can be performed by a second terminal device, or a component (such as a chip or circuit) that can be configured in the second terminal device. The method includes:

[0007] Receive first indication information, where the first indication information is used to instruct the second terminal device to monitor paging messages for the first terminal device; and monitor the paging messages sent by the network device for the first terminal device.

[0008] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0009] Therefore, the embodiment of the present application can enable the second terminal device to determine that the RRC state of the first terminal device is RRC idle state or RRC inactive state by instructing the second terminal device to monitor the paging message of the first terminal device, and determine that it is necessary to monitor the paging message for the first terminal device, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device. For example, the network device, the first terminal device, and the second terminal device all perceive that the first terminal device is in the RRC idle state, inactive state, or connected state.

[0010] When the network device, the first terminal device, and the second terminal device align the RRC state of the first terminal device, more efficient data transmission can be achieved between the network device, the first terminal device, and the second terminal device. For example, the second terminal device can determine that the first terminal device monitors paging messages or receives downlink data / signaling transmissions, and the second terminal device receives and forwards paging messages or data from the network device.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0012] Send second indication information to the first terminal device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0013] Therefore, in an embodiment of the present application, the second terminal device can further instruct the first terminal device to enter the RRCidle state or the RRC inactive state, thereby causing the first terminal device to enter the RRC idle state or the RRC inactive state, which helps to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0014] In some possible implementations, the second terminal device may also send indication information to the first terminal device to further indicate whether the first terminal device enters the RRC idle state or the RRC inactive state. Optionally, the second terminal device may determine whether the first terminal device enters the RRC idle state or the RRC inactive state according to the indication of the network device, which is not limited in this application. The indication may be sent in the same message as the first indication information, or in different messages, which is not limited in this application.

[0015] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0016] Send third indication information to the first terminal device, the third indication information is used to instruct the first terminal device to release the sidelink configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device. As an example, the sidelink configuration can be a PC5 configuration, and the PC5 configuration can include, for example, a sidelink radio bearer (SLRB) configuration, a MAC configuration, a radio link control (RLC) bearer configuration, and an RLC configuration. The air interface link configuration can be, for example, an NR air interface data radio bearer (DRB) configuration, a signaling radio bearer (DRB), a PDCP configuration, an SDAP configuration, and the like.

[0017] Therefore, in an embodiment of the present application, by instructing the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device, the first terminal device can release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device when entering the RRC idle state or the RRC inactive state.

[0018] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0019] Determine that the RRC states between the network device and the first terminal device are not aligned. That is, when it is determined that the RRC states between the network device and the first terminal device are not aligned, the second terminal device can determine, based on the first indication information, that the first terminal device is monitoring the paging message, that is, determine that the first terminal device is in the RRC idle state or the RRC inactive state.

[0020] As an example, when it is determined that a first message from a network device is not successfully received or the first message is not successfully decoded, it can be determined that the RRC states between the network device and the first terminal device are not aligned, wherein the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device. Exemplarily, the first message can be an RRC connection release message, or an RRC connection release with suspend message, which is not limited to this.

[0021] In combination with the first aspect, in some implementations of the first aspect, the first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to instruct the first terminal device to enter an idle state; or

[0022] The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

[0023] In combination with the first aspect, in some implementations of the first aspect, the first indication information comes from the network device. Therefore, in an embodiment of the present application, the network device can determine that the first terminal device enters the RRC idle state or the RRC inactive state, for example, when it is not necessary to send downlink data / signaling to the first terminal device, it can determine that the first terminal device enters the RRC idle state or the RRC inactive state, and instruct the second terminal device to monitor the paging message for the first terminal device.

[0024] In combination with the first aspect, in some implementations of the first aspect, the first indication information is carried in an RRC message or MAC CE sent by the network device to the second terminal device. In this way, the first indication information can be sent through an existing message.

[0025] In combination with the first aspect, in some implementations of the first aspect, the first indication information comes from the first terminal device. Therefore, in an embodiment of the present application, the first terminal device can determine to enter the RRC idle state or the RRC inactive state, for example, it can determine to enter the RRC idle state or the RRC inactive state when there is no need to send uplink data / signaling to the network device, and instruct the second terminal device to monitor the paging message for the first terminal device.

[0026] In conjunction with the first aspect, in some implementations of the first aspect, the paging message is used by the network device to page the first terminal device. For example, the network device may send the paging message when it needs to send downlink data / signaling to the first terminal device.

[0027] In conjunction with the first aspect, in some implementations of the first aspect, the first indication information includes an identifier of the first terminal device. In this case, the paging message sent by the network device to the first terminal device can be monitored according to the identifier of the first terminal device.

[0028] In an embodiment of the present application, by including the identifier of the first terminal device in the first indication information, the second terminal device can monitor the paging message for the first terminal device according to the identifier of the first terminal device when communicating with the multiple terminal devices through the side link at the same time, thereby enabling the second terminal device to monitor the paging message for the first terminal device among the multiple terminal devices, or each terminal device among the multiple terminal devices, when communicating with the multiple terminal devices through the side link at the same time.

[0029] In conjunction with the first aspect, in some implementations of the first aspect, the method further includes:

[0030] Receive a paging message sent by the network device for the first terminal device, and send the paging message to the first terminal device via the sidelink. Here, receiving a paging message sent by the network device for the first terminal device may refer to obtaining or monitoring a paging message sent by the network device for the first terminal device, and this is not limited.

[0031] Therefore, in an embodiment of the present application, after the second terminal device aligns the RRC state of the first terminal device with the network device to the RRC idle state or the RRC inactive state, it can receive a paging message sent by the network device for paging the first terminal device, and can send the paging message to the first terminal device, thereby helping the first terminal device to enter the RRC idle state or the RRC inactive state according to the paging message.

[0032] In combination with the first aspect, in certain implementations of the first aspect, before sending the paging message to the first terminal device via the sidelink, the sidelink may be established or rebuilt. For example, when the second terminal device has released or has not established the sidelink before sending the paging message via the sidelink, the sidelink may be established or rebuilt to send the paging message.

[0033] In a second aspect, a communication method is provided, which can be performed by a first terminal device, or a component (such as a chip or circuit) that can be configured in the first terminal device. The method includes:

[0034] Receive second indication information from the second terminal device, and / or receive a paging message forwarded by the second terminal device, wherein the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state, and the paging message is used by the network device to page the first terminal device; enter an idle state or a deactivated state.

[0035] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0036] Therefore, in an embodiment of the present application, the second terminal device can indicate or forward to the first terminal device a paging message used to page the first terminal device, so that the first terminal device can enter the RRC idle state or the RRC inactive state according to the indication or the received paging message, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0037] In some possible implementations, the second terminal device may also send indication information to the first terminal device to further indicate whether the first terminal device enters the RRC idle state or the RRC inactive state, which is not limited in this application.

[0038] In conjunction with the second aspect, in some implementations of the second aspect, the method further includes:

[0039] Receive third indication information from the second terminal device, the third indication information is used to instruct the first terminal device to release the sidelink configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device. As an example, the sidelink configuration can be a PC5 configuration, and the PC5 configuration can include, for example, a sidelink radio bearer (SLRB) configuration, a MAC configuration, a radio link control (RLC) bearer configuration, and an RLC configuration. The air interface link configuration can be, for example, an NR air interface configuration.

[0040] Therefore, in an embodiment of the present application, the second terminal device instructs the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device, so that the first terminal device can release the side link configuration between the second terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device when entering the RRC idle state or the RRC inactive state.

[0041] In conjunction with the second aspect, in certain implementations of the second aspect, before receiving the second indication information from the second terminal device and / or receiving the paging message from the network device forwarded by the second terminal device, the sidelink may be established or reestablished. For example, when the second terminal device has released or has not established the sidelink before sending the second indication information and / or the paging message through the sidelink, the sidelink may be established or reestablished to send the paging message.

[0042] In combination with the second aspect, in certain implementations of the second aspect, after receiving a paging message from a network device forwarded by the second terminal device, entering the idle state or deactivated state may also include initiating an RRC establishment / recovery process with the network device.

[0043] In this way, the first terminal device can release the previous old air interface link configuration by entering the RRC idle state or the RRC inactive state, and initiate the RRC establishment / recovery process with the network device according to the paging message, establish or restore the RRC connection, and realize the reconfiguration of the RRC link.

[0044] In a third aspect, a communication method is provided, which can be performed by a first terminal device, or a component (such as a chip or circuit) that can be configured in the first terminal device. The method includes:

[0045] Determining that the first terminal device enters an idle state or a deactivated state;

[0046] Send first indication information to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor paging messages for the first terminal device.

[0047] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0048] Therefore, in an embodiment of the present application, the first terminal device can determine to enter the RRC idle state or the RRC inactive state. When determining to enter the RRC idle state or the RRC inactive state, the first terminal device can instruct the second terminal device to listen to the paging message for the first terminal device, that is, indicate to the second terminal device that its RRC state is the RRC idle state or the RRC inactive state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0049] In combination with the third aspect, in certain implementations of the third aspect, it may be determined that the idle state or deactivated state is entered when it is determined that no data or signaling of the first terminal device is received or sent in the first time period. For example, when it is determined that no UL data / signaling needs to be sent to the network device in the first time period, and no DL data / signaling sent by the second terminal device from the network device is received in the first time period, it is determined that the idle state or deactivated state is entered.

[0050] As a possible implementation, the first terminal device side may set a timer to determine that the idle state or deactivated state has been entered when no data or signaling of the first terminal device is received or sent for a first period of time. Optionally, the first terminal device may start or restart the timer when receiving or sending data / signaling.

[0051] In a fourth aspect, a communication method is provided, which can be performed by a network device or a component (such as a chip or circuit) that can be configured in the network device. The method includes:

[0052] A first message is sent, where the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; and a first indication information is sent to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor the paging message for the first terminal device.

[0053] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0054] Therefore, in an embodiment of the present application, the network device can instruct the second terminal device to listen to the paging message of the first terminal device when releasing or suspending the RRC connection between the first terminal device and the network device, so that the second terminal device can determine that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state, and determine that it is necessary to listen to the paging message for the first terminal device, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0055] In combination with the fourth aspect, in some implementations of the fourth aspect, the first message may be sent to the second terminal device. When the first message is successfully sent to the second terminal device and is successfully decoded by the second terminal device, the second terminal device can determine, based on the first message, that the RRC state of the first terminal device is an RRC idle state or an RRC inactive state.

[0056] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device. At this time, the second terminal device cannot determine (i.e., does not know) the RRC state of the first terminal device because it cannot read the RRC message sent by the network device to the first terminal device.

[0057] As a possible implementation manner, the network device can determine whether the first message is successfully sent to the second terminal device or whether the first message is successfully decoded by the second terminal device by whether a feedback message corresponding to the above-mentioned first message sent by the second terminal device is received.

[0058] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the following further includes:

[0059] Receive negative feedback information, where the negative feedback information is used to indicate that the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device. In this way, the network device can determine that the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device, based on the negative feedback information.

[0060] In combination with the fourth aspect, in certain implementations of the fourth aspect, the paging message is used by the network device to page the first terminal device.

[0061] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter an idle state. Exemplarily, the first message can be an RRC connection release message, which is not limited in this application.

[0062] Alternatively, the first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state. Exemplarily, the first message may be an RRC connection release with suspend message, which is not limited in this application.

[0063] In conjunction with the fourth aspect, in some implementations of the fourth aspect, the first indication information includes an identifier of the first terminal device. Here, by including the identifier of the first terminal device in the first indication information, the second terminal device can monitor the paging message for the first terminal device according to the identifier of the first terminal device when communicating with the multiple terminal devices through the sidelink at the same time.

[0064] In combination with the fourth aspect, in certain implementations of the fourth aspect, before sending the first indication information to the second terminal device, a paging message or an RRC establishment message may also be sent to the second terminal device. Therefore, in the embodiment of the present application, for a second terminal device in an RRC idle state or an RRC inactive state, the paging message or the RRC establishment message may be sent so that the second terminal device can enter an RRC connected state from an RRC idle state or an RRC inactive state, and after entering the RRC connected state, receive a message or information sent by a network device, such as the above-mentioned first message, or the first indication information.

[0065] In combination with the fourth aspect, in certain implementations of the fourth aspect, the first indication information is carried in an RRC message or a media access control element MAC CE.

[0066] In a fifth aspect, a communication method is provided, which can be performed by a second terminal device, or a component (such as a chip or circuit) that can be configured in the second terminal device. The method includes:

[0067] The second terminal device determines that no data or signaling of the first terminal device is received and / or sent during the first period of time;

[0068] Determine whether the first terminal device enters an idle state or a deactivated state.

[0069] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0070] Therefore, in an embodiment of the present application, the second terminal device can determine that the first terminal device has entered an idle state or a deactivated state by determining that no data or signaling of the first terminal device has been received or sent for a first period of time, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0071] Exemplarily, the second terminal device can determine that the first terminal device enters an idle state or a deactivated state when it has not received DL data / signaling sent by the network device that needs to be forwarded to the first terminal device within a first period of time, and when it has not received UL data / signaling sent by the first terminal device that needs to be forwarded to the network device within a first period of time.

[0072] In combination with the fifth aspect, in certain implementations of the fifth aspect, the paging message sent by the network device to the first terminal device may also be monitored. In this way, the second terminal device may monitor the paging message sent by the network device to the first terminal device when determining that the first terminal device enters the RRCidle state or the RRC inactive state.

[0073] In combination with the fifth aspect, in certain implementations of the fifth aspect, second indication information may also be sent to the network device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0074] In this way, the second terminal device can indicate to the network device that the first terminal device enters the idle state or the deactivated state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0075] In conjunction with the fifth aspect, in some implementations of the fifth aspect, the present invention further includes:

[0076] Receive downlink data and / or signaling from the network device, and forward the downlink data and / or signaling to the first terminal device, the downlink data and / or signaling can trigger the first terminal device to initiate an RRC establishment / recovery process. Here, the downlink data / signaling does not include an RRC release message.

[0077] In conjunction with the fifth aspect, in some implementations of the fifth aspect, the second terminal device may set a first timer, and when determining that the first timer has timed out, determine that no data or signaling of the first terminal device has been received or sent within the first time period. As an example, the timer may be a data inactivity timer, which is not limited in this application.

[0078] In combination with the fifth aspect, in certain implementations of the fifth aspect, the first timer can be set to time out when the first duration is reached, and the first timer can be started or restarted when receiving or sending data or signaling of the first terminal device.

[0079] In conjunction with the fifth aspect, in some implementations of the fifth aspect, the first duration is configured by the network device. As an example, the second terminal device may receive indication information from the network device to determine the first duration, wherein the indication information is used to indicate the first duration.

[0080] In conjunction with the fifth aspect, in some implementations of the fifth aspect, the second terminal device may further send fourth indication information to the first terminal device, where the fourth indication information is used to indicate the first duration. For example, when the first duration is determined by the second terminal device or configured by the network device, the second terminal device may indicate the first duration to the first terminal device.

[0081] Therefore, the embodiment of the present application can align the first duration by having the network device indicate the first duration to the second terminal device, and / or the second terminal device indicate the first duration to the first terminal device, thereby helping to achieve alignment of the RRC states of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0082] In some possible implementations, the first duration may be determined by the second terminal device or predefined by a protocol, which is not limited in this application.

[0083] In some possible implementations, the first duration may be configured by the first terminal device. As an example, the second terminal device may receive indication information from the first terminal device to determine the first duration.

[0084] Optionally, when the first duration is determined by the second terminal device or configured by the first terminal device, the second terminal device may also indicate the first duration to the network device.

[0085] In a sixth aspect, a communication method is provided, which can be performed by a first terminal device, or a component (such as a chip or circuit) that can be configured in the first terminal device. The method includes:

[0086] The first terminal device determines that no data or signaling is received from the network device during a first period of time, and / or no data or signaling is sent to the network device; and determines that the first terminal device enters an idle state or a deactivated state.

[0087] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device may be a remote terminal device, and the second terminal device may be a relay terminal device, which is not limited in this application.

[0088] Therefore, in an embodiment of the present application, the first terminal device can determine that the first terminal device has entered an idle state or a deactivated state by determining that no data or signaling of the first terminal device has been received or sent for a first period of time, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0089] As an example, the first terminal device may determine that the first terminal device enters an idle state or a deactivated state when it is determined that there is no UL data / signaling that needs to be sent to the network device within a first time period, and when no DL data / signaling sent by the second terminal device from the network device is received within the first time period.

[0090] In conjunction with the sixth aspect, in some implementations of the sixth aspect, the following further includes:

[0091] Send second indication information to the second terminal device or the network device, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state.

[0092] In this way, the first terminal device can indicate to the second terminal device or the network device that the first terminal device enters the idle state or the deactivated state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0093] In conjunction with the sixth aspect, in some implementations of the sixth aspect, the following further includes:

[0094] Receiving downlink data and / or signaling from the network device forwarded by the second terminal device;

[0095] Initiate an RRC establishment / recovery process with the network device.

[0096] Here, the downlink data / signaling does not include an RRC release message. Therefore, in an embodiment of the present application, when the first terminal device is in an RRC idle state or an RRC inactive state, if the first terminal device receives downlink data and / or signaling from a network device forwarded by a second terminal device, the first terminal device can initiate an RRC establishment / recovery process with the network device to receive the downlink data and / or signaling.

[0097] In conjunction with the sixth aspect, in certain implementations of the sixth aspect, the first terminal device may set a second timer, and when determining that the second timer has timed out, determine that no data or signaling has been received from the network device during the first time period, and / or that no data or signaling has been sent to the network device. As an example, the timer may be a data inactivity timer, which is not limited in this application.

[0098] In combination with the sixth aspect, in certain implementations of the sixth aspect, a second timer can be set to time out when the first duration is reached, and when receiving data or signaling from the network device, and / or sending data or signaling to the network device, the second timer can be started or restarted.

[0099] In conjunction with the sixth aspect, in some implementations of the sixth aspect, the following further includes:

[0100] Receive fourth indication information from the second terminal device, wherein the fourth indication information is used to indicate the first duration. Therefore, in the embodiment of the present application, the second terminal device indicates the first duration to the first terminal device, and the first duration can be aligned, thereby facilitating the alignment of the RRC state of the first terminal device by the network device, the first terminal device, and the second terminal device.

[0101] In some possible implementations, the first duration may be determined by the first terminal device or predefined by a protocol, which is not limited in this application.

[0102] In some possible implementations, the first duration may be configured by a network device. As an example, the first terminal device may receive indication information from the network device to determine the first duration.

[0103] Optionally, when the first duration is determined by the first terminal device or configured by the second terminal device, the first terminal device may also indicate the first duration to the network device.

[0104] In a seventh aspect, a communication method is provided, which can be performed by a network device or a component (such as a chip or circuit) that can be configured in a network device. The method includes:

[0105] The network device determines that no data or signaling of the first terminal device is received and / or sent during a first period of time; and determines that the first terminal device enters an idle state or a deactivated state.

[0106] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. For example, the first terminal device can be a remote terminal device, and the second terminal device can be a relay terminal device, which is not limited in this application.

[0107] Therefore, in an embodiment of the present application, the network device can determine that the first terminal device has entered an idle state or a deactivated state by determining that no data or signaling of the first terminal device has been received or sent for a first period of time, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0108] As an example, the network device may determine that there is no DL data / signaling that needs to be sent to the first terminal device during a first period of time, and determine that the first terminal device enters an idle state or a deactivated state when no UL data / signaling is received from the first terminal device during the first period of time.

[0109] In conjunction with the seventh aspect, in some implementations of the seventh aspect, the present invention further includes:

[0110] Send first indication information to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor paging messages for the first terminal device.

[0111] Therefore, in an embodiment of the present application, when the network device determines that the first terminal device has entered the RRC idle state or the RRC inactive state, the network device can instruct the second terminal device to listen to the paging message of the first terminal device, so that the second terminal device can determine that it needs to listen to the paging message for the first terminal device, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0112] In conjunction with the seventh aspect, in some implementations of the seventh aspect, the present invention further includes:

[0113] Send second indication information to the second terminal device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0114] Therefore, in an embodiment of the present application, when determining that the first terminal device has entered the RRC idle state or the RRC inactive state, the network device can instruct the second terminal device to monitor the first terminal device entering the RRC idle state or the RRC inactive state, thereby enabling the second terminal device to determine that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state, which helps to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0115] In combination with the seventh aspect, in certain implementations of the seventh aspect, the network device may set a third timer, and when it is determined that the third timer has expired, it is determined that no data or signaling from the first terminal device has been received or sent within the first time period.

[0116] In combination with the seventh aspect, in certain implementations of the seventh aspect, the second timer can be set to time out when the first duration is reached, and the third timer can be started or restarted when receiving or sending data or signaling of the first terminal device.

[0117] In combination with the seventh aspect, in certain implementations of the seventh aspect, the network device may further determine the first duration.

[0118] In combination with the seventh aspect, in certain implementations of the seventh aspect, the network device may further send fourth indication information to the second terminal device, where the fourth indication information is used to indicate the first duration.

[0119] Therefore, the embodiment of the present application indicates the first duration to the second terminal device through the network device, and can align the first duration, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0120] In some possible implementations, the network device may receive indication information from the first terminal device or the second terminal device to determine the first duration, which is not limited in this application.

[0121] In an eighth aspect, a communication method is provided, which can be performed by a second terminal device, or a component (such as a chip or circuit) that can be configured in the second terminal device. The method includes:

[0122] The second terminal device receives second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state; the second terminal device determines that the first terminal device is in an idle state or a deactivated state based on the second indication information.

[0123] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device may be a remote terminal device, and the second terminal device may be a relay terminal device, which is not limited in this application.

[0124] Therefore, the embodiment of the present application helps to align the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device by indicating to the second terminal device that the RRC state of the first terminal device is RRCidle state or RRC inactive state.

[0125] In combination with the eighth aspect, in certain implementations of the eighth aspect, the second indication information comes from the first terminal device.

[0126] In combination with the eighth aspect, in certain implementations of the eighth aspect, the second indication information may also be sent to the network device.

[0127] In combination with the eighth aspect, in certain implementations of the eighth aspect, the second indication information comes from the network device.

[0128] In a ninth aspect, a communication method is provided, which can be performed by a network device or a component (such as a chip or circuit) that can be configured in a network device. The method includes:

[0129] The network device receives second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state; the network device determines that the first terminal device is in an idle state or a deactivated state based on the second indication information.

[0130] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device may be a remote terminal device, and the second terminal device may be a relay terminal device, which is not limited in this application.

[0131] Therefore, the embodiment of the present application indicates to the network device that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0132] In combination with the ninth aspect, in certain implementations of the ninth aspect, the second indication information comes from the first terminal device or the second terminal device.

[0133] In a tenth aspect, a communication method is provided, which can be performed by a first terminal device, or a component (such as a chip or circuit) that can be configured in the first terminal device. The method includes:

[0134] The first terminal device receives second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state; and enters an idle state or a deactivated state.

[0135] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate through a side link. As an example, the first terminal device may be a remote terminal device, and the second terminal device may be a relay terminal device, which is not limited in this application.

[0136] Therefore, the embodiment of the present application helps to align the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device by indicating to the first terminal device that the RRC state of the first terminal device is in the RRCidle state or the RRC inactive state.

[0137] In combination with the tenth aspect, in certain implementations of the tenth aspect, the second indication information comes from the second terminal device or the network device.

[0138] In the eleventh aspect, a communication device is provided for executing the method in any aspect of the first to tenth aspects or any possible implementation of any aspect. Specifically, the device includes a unit or module for executing the method in any aspect of the first to tenth aspects or any possible implementation of any aspect.

[0139] In a twelfth aspect, a communication device is provided, comprising: a processor and a transceiver. Optionally, a memory may also be included. The memory is used to store instructions, and the processor is used to execute the instructions stored in the memory, and when the processor executes the instructions stored in the memory, the execution causes the processor to execute the method in any aspect of the first to tenth aspects or any possible implementation of any aspect.

[0140] In the thirteenth aspect, a communication chip is provided, comprising a processor and a communication interface, wherein the processor is used to call and run instructions from the communication interface, and when the processor executes the instructions, the method in any aspect of the first to tenth aspects or any possible implementation of any aspect is implemented.

[0141] Optionally, the communication chip may further include a memory, in which instructions are stored, and the processor is used to execute the instructions stored in the memory or instructions from other sources. When the instructions are executed, the processor is used to implement the method in any aspect of the first to tenth aspects or any possible implementation of any aspect.

[0142] In a fourteenth aspect, a computer-readable medium is provided for storing a computer program, wherein the computer program comprises instructions for executing a method in any one of the first to tenth aspects or any possible implementation of any one of the aspects.

[0143] In a fifteenth aspect, an embodiment of the present application further provides a computer program product comprising instructions, which, when executed on a computer, enables the computer to execute a method in any one of the first to tenth aspects or any possible implementation of any one of the aspects.

[0144] In the sixteenth aspect, a communication system is provided, which includes a network device, a first terminal device and a second terminal device, wherein the network device, the first terminal device and the second terminal device can refer to the description of each aspect in the above-mentioned first to tenth aspects.

[0145] It should be understood that the beneficial effects achieved by the eleventh to sixteenth aspects of the present application and the corresponding implementation methods can be referred to the beneficial effects achieved by the first to tenth aspects of the present application and the corresponding implementation methods, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0146] Figure 1 is a schematic diagram of a communication system suitable for the present application;

[0147] Figure 2 It is a schematic diagram of the protocol stack of the U2N relay;

[0148] Figure 3 It is a schematic diagram of the RRC connection state transition of the terminal device;

[0149] Figure 4 is a schematic flow chart of a communication method provided in an embodiment of the present application;

[0150] Figure 5 is a schematic flow chart of another communication method provided in an embodiment of the present application;

[0151] Figure 6 is a schematic flow chart of another communication method provided in an embodiment of the present application;

[0152] Figure 7 is a schematic flow chart of another communication method provided in an embodiment of the present application;

[0153] Figure 8 is a schematic diagram of a wireless communication device provided in an embodiment of the present application;

[0154] Fig. 9 It is a structural schematic diagram of a terminal device provided by this application;

[0155] Fig.10 It is a structural diagram of a network device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0156] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0157] The technical solutions of the embodiments of the present application can be applied to various communication systems, for example: global system of mobile communication (GSM) system, code division multiple access (CDMA) system, wideband code division multiple access (WCDMA) system, general packet radio service (GPRS), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), universal mobile telecommunication system (UMTS), worldwide interoperability for microwave access (WiMAX) communication system, fifth generation (5G) system or new radio (NR), etc.

[0158] Generally speaking, traditional communication systems support a limited number of connections and are easy to implement. However, with the development of communication technology, mobile communication systems will not only support traditional communications, but will also support, for example, internet of things (IoT) communications, device to device (D2D) communications, machine to machine (M2M) communications, machine type communications (MTC), vehicle to everything (V2X) communications, vehicle to vehicle (V2V) communications, vehicle to pedestrian (V2P) communications, vehicle to infrastructure (vehicle to infrastructure) communications, etc., without limitation.

[0159] The terminal device involved in the embodiments of the present application may be a device that provides voice and / or data connectivity to a user, a handheld device with a wireless connection function, other processing devices connected to a wireless modem, or a vehicle-mounted device, etc. The wireless terminal may communicate with one or more core networks via a radio access network (RAN), and may also support direct communication between terminal devices. At present, some examples of terminals are: mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MID), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self driving, wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, cellular phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), handheld devices with wireless communication functions, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, terminal devices in future 5G networks or future evolved public land mobile communication networks (public land mobile The embodiments of the present application do not limit this.

[0160] As an example but not limitation, in the embodiments of the present application, the terminal device may also be a wearable device. Wearable devices may also be referred to as wearable smart devices, which are a general term for wearable devices that are intelligently designed and developed using wearable technology for daily wear, such as glasses, gloves, watches, clothing, and shoes. A wearable device is a portable device that is worn directly on the body or integrated into the user's clothes or accessories. Wearable devices are not only hardware devices, but also powerful functions achieved through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include full-featured, large-sized, and fully or partially independent of smartphones, such as smart watches or smart glasses, as well as devices that only focus on a certain type of application function and need to be used in conjunction with other devices such as smartphones, such as various types of smart bracelets and smart jewelry for vital sign monitoring.

[0161] In addition, in the embodiments of the present application, the terminal device may also be a terminal device in an Internet of Things (IoT) system. IoT is an important part of the future development of information technology. Its main technical feature is to connect objects to the network through communication technology, thereby realizing an intelligent network that interconnects people and machines and things.

[0162] The network device involved in the embodiment of the present application can be any device deployed in a wireless access network to provide wireless communication functions for terminal devices. The network device may include various forms of macro base stations, micro base stations (also called small stations), relay stations, access points, etc. In systems using different wireless access technologies, the names of network devices may be different, such as base transceiver stations (BTS) in global system for mobile communication (GSM) or code division multiple access (CDMA) networks, NB (NodeB) in wideband code division multiple access (WCDMA), eNB or eNodeB (Evolutional NodeB) in long term evolution (LTE). The network device can also be a wireless controller in a cloud radio access network (CRAN) scenario. The network device can also be a base station gNB device in a 5G network or a network device in a future evolved PLMN network. The network device can also be a wearable device or a vehicle-mounted device. The network device can also be a transmission and reception point (TRP).

[0163] First, the application scenario of this application is introduced. Figure 1 is a schematic diagram of a communication system applicable to the present application. Exemplarily, the communication system may be a V2X communication system, but the present application is not limited thereto. Figure 1 As shown, the communication system may include a network device 110, a terminal device 120, a terminal device 130, a terminal device 140, a terminal device 150, a terminal device 160, a terminal device 170, and a terminal device 180. These terminal devices may be, for example, vehicles, and may communicate with the network device 110 via a wireless link. As an example, the terminal device may communicate with the network device 110 via electromagnetic waves.

[0164] exist Figure 1In the embodiment, the network device 110 can perform signaling and / or data transmission with one or more of the above-mentioned 7 terminal devices. For example, the terminal device 120 or the terminal device 130 can send uplink data and / or signaling to the network device 110, and the network device 110 can receive uplink data and / or signaling sent by the terminal device 120 or the terminal device 130. For another example, the network device 110 can also send downlink data and / or signaling to the terminal device 120, the terminal device 180 and the terminal device 130, and the terminal device 130 can also send downlink data and / or signaling to the terminal device 140, the terminal device 150, and the terminal device 160, or the terminal device 130 can also send data and / or signaling to the terminal device 140, the terminal device 150, and the terminal device 160 on the side link. In addition, the terminal device 160, the terminal device 170 and the terminal device 180 may also form a communication system, wherein the terminal device 180 may send data and / or signaling to the terminal device 160 and the terminal device 170 on the side link. That is to say, the communication system applied in the embodiment of the present application includes not only the communication between the terminal device and the network device, but also the communication between the terminal devices.

[0165] It should be noted that the multiple terminal devices shown in the embodiment of the present application are for better and more comprehensive description of the embodiment of the present application, but should not impose any limitation on the embodiment of the present application. For example, in actual application, there may be only one or more terminal devices.

[0166] It should be understood that the communication system 100 is only an example, and the communication system applicable to the present application is not limited thereto. For example, the number of network devices and terminal devices included in the communication system 100 can also be other numbers, or the terminal device can also be other types of terminal devices.

[0167] exist Figure 1 In the embodiment, terminal device 130 and terminal device 180 can be used as relay terminal devices (i.e., relay nodes), and terminal device 140, terminal device 150, terminal device 160 and terminal device 170 can be used as remote terminal devices (i.e., remote nodes). Remote terminal devices can communicate with network devices through relay terminal devices, or remote devices can communicate with each other through relay terminal devices.

[0168] Figure 2 FIG. 1 shows a schematic diagram of a protocol stack for UE to network (U2N) relay. Figure 2As shown, the remote terminal device has two sets of protocol stack structures, namely the NR protocol stack structure and the PC5 protocol stack structure, wherein the NR protocol stack includes the application (APP) layer, the protocol data unit (PDU) layer, the NR-service data adaptation protocol (SDAP) layer, the NR-packet data convergence protocol (PDCP) layer, etc., and the PC5 protocol stack includes the PC5-radio link control (RLC) layer, the PC5-media access control (MAC) layer, and the PC5-physical (PHY) layer. The relay terminal device also has two sets of protocol stack structures, namely the NR protocol stack structure and the PC5 protocol stack structure, wherein the NR protocol stack includes the NR-RLC layer, the NR-MAC layer, and the NR-PHY layer. NG-RAN (also known as 5G-RAN) includes the NR protocol stack structure and the N3 stack, wherein the NR protocol stack structure includes the NR-SDAP layer, the NR-PDCP layer, the NR-RLC layer, the NR-MAC layer, and the NR-PHY layer. UPF, such as a PDU session anchor, may include the PDU layer and the N3stack.

[0169] exist Figure 2 In the NR protocol stack structure of the remote terminal device, the NR protocol stack structure can communicate with the NG-RAN or UPF or other network side devices, and the PC5 protocol stack can communicate with the PC5 protocol stack in the relay terminal device. The NR protocol stack in the relay terminal device can communicate with the NR structure stack in the NG-RAN.

[0170] It should be noted that Figure 2 In the description, the NR protocol stack is taken as the protocol stack for the uplink and downlink links, and the PC5 protocol stack is taken as the side link (SL) between terminal devices, but the embodiments of the present application are not limited to this.

[0171] Below, the RRC connection state involved in this application is explained.

[0172] There are three RRC connection states: RRC idle state, RRC connected state, and RRC inactive state.

[0173] 1) When the terminal device is in the RRC idle state, it generally cannot transmit data with the network device, and the terminal device and the network device do not save the context of the terminal device, but the core network device saves the context of the terminal device. At the same time, there is no signaling connection dedicated to the terminal device between the core network device and the network device. At this time, the terminal device can implement mobility processing through cell selection or reselection. Exemplarily, the terminal device in the RRC idle state can perform the following actions:

[0174] Monitor short messages transmitted via downlink control information (DCI) and scrambled using a paging radio network temporary identifier (P-RNTI);

[0175] Monitoring a paging channel used for core network (CN) paging. For example, the S-temporary mobile subscriber identity (S-TMSI) allocated by the core network device to the terminal device may be used to monitor the paging channel;

[0176] Perform neighbor cell measurements and cell selection / reselection;

[0177] Get system information and send system information (SI) request (if configured).

[0178] 2) When the terminal device is in the RRC connected state, the core network device and the access device both have the context of the terminal device, and the RRC connection is maintained between the terminal device and the access device, and the terminal device can perform uplink and downlink data transmission. Exemplarily, the terminal device in the RRC connected state can perform the following actions:

[0179] Monitor short messages transmitted via DCI and scrambled using P-RNTI (if configured);

[0180] monitoring a control channel associated with the shared data channel to determine whether the network device has scheduled data for it;

[0181] Provide channel quality and feedback information;

[0182] Perform neighbor cell measurements and measurement reporting;

[0183] Get system information.

[0184] 3) When the terminal device is in the RRC inactive state, the terminal device and the access device store the AS context of the terminal device, and the core network device also has the terminal device context. In addition, there is a signaling connection dedicated to the terminal device between the core network device and the access device, and the terminal device and the access device do not need to maintain the RRC connection to reduce the signaling overhead and power consumption of the terminal device. Therefore, when the terminal device switches from the RRC inactive state to the RRC connected state, the core network device does not need to participate, and data transmission can be carried out quickly. At this time, the terminal device can implement mobility processing through cell reselection.

[0185] Exemplarily, a terminal device in the RRC inactive state may perform the following actions:

[0186] Monitor the short message transmitted via DCI and scrambled using P-RNTI;

[0187] Monitor the paging channel used for CN paging, for example, the S-TMSI allocated by the core network device to the terminal device can be used to monitor the paging channel;

[0188] Monitoring a paging channel for RAN paging, for example, using RNTI (RNTI) to monitor the paging channel;

[0189] Perform neighbor cell measurements and cell selection / reselection;

[0190] Perform RNA-based notification area updates periodically or when moving outside of the configured RAN-based notification area;

[0191] Get system information and send SI request (if configured).

[0192] It can be seen that for the core network equipment, the terminal equipment in the inactive state is similar to the terminal equipment in the connected state. For the access equipment, the terminal equipment in the inactive state is similar to the terminal equipment in the idle state. There is no real-time RRC connection and data transmission, and downlink data needs to be sent to the terminal equipment through paging. For the inactive state, since the dedicated connection between the core network equipment and the access equipment is not released, the access equipment side stores the context of the terminal equipment, which can speed up the recovery of the terminal equipment to the connected state and quickly transmit data.

[0193] Figure 3An example of RRC connection state transition of a terminal device in an LTE communication system and an NR communication system is shown. The RRC connection state in the LTE communication system may include, for example, an evolved UMTS terrestrial radio access (EUTRA) RRC connected state, an EUTRA RRC inactive state, and an EUTRA RRC idle state. The RRC connection state in the NR communication system may include, for example, an NR RRC connected state, an NR RRC inactive state, and an NR RRC idle state.

[0194] like Figure 3 As shown, in an LTE or NR communication system, a terminal device can switch between an RRC connected state and an RRC inactive state, for example, it can suspend (also called temporary release, release with suspend) in the RRC connected state and enter the inactive state, and it can resume (resume) in the inactive state to enter the connected state. The terminal device can also switch between an RRC connected state and an RRC idle state, for example, it can release (release) in the RRC connected state to enter the RRC idle state, and it can establish (establish) RRC in the RRC idle state to enter the RRC connected state. The terminal device can also release (release) in the inactive state to enter the idle state.

[0195] In addition, the terminal device can also switch between the EUTRA RRC connected state and the NR connected state through handover, switch between the EUTRA RRC idle state and the NR RRC idle state through reselection, or enter the NR RRC idle state from the EUTRA RRC inactive state through reselection, or enter the EUTRA RRC idle state from the NR RRC inactive state through reselection.

[0196] When the network device has downlink data to send, but the terminal device is in RRC idle state or RRC inactive state, the network device will initiate paging. Or, when there is system information update, the network device will also inform the terminal device that the system information has been updated through paging.

[0197] That is to say, paging allows network devices to reach terminal devices in RRC idle state and RRC inactive state through paging messages, or to notify terminal devices in RRC idle state, RRC inactive state and RRC connected state of system information changes and earthquake tsunami warning system (ETWS) / commercial mobile alert system (CMAS) indications through short messages. Both paging messages and short messages are addressed with P-RNTI on the physical downlink control channel (PDCCH). Paging messages are sent on the paging control channel (PCCH), and short messages are sent directly on the PDCCH. Among them, the paging message is sent to the terminal device through the physical downlink shared channel (PDSCH) resource location indicated by the PDCCH scrambled by P-RNTI.

[0198] On the terminal device side, when the terminal device is in the RRC idle state, the terminal device can monitor the paging channel to receive the paging message initiated by the CN. When the terminal device is in the RRC inactive state, the terminal device can monitor the paging channel to receive the paging message initiated by the RAN. The terminal device may not need to continuously monitor the paging channel. For example, in the defined paging discontinuous reception (DRX) cycle, the terminal device in the RRC idle state or inactive state only needs to monitor the paging channel during one paging occasion (PO) in each DRX cycle. In this way, the terminal device can wake up to receive the paging message within a predetermined time period and remain in a dormant state in other time periods, which can reduce power consumption and extend the battery life of the terminal device.

[0199] For example, the terminal device may attempt to receive a paging message at a specific PO of a paging frame (PF) in a paging cycle. One PO may contain multiple slots, and the PO is not necessarily a subframe. Accordingly, the network device needs to send the paging message from the air interface at the corresponding time, so that the terminal device may receive the paging message at this time.

[0200] In summary, the terminal device can receive paging messages in the RRC idle state or the RRC inactive state, and can receive paging system message update indications and other paging notification messages in the RRC connected state, the RRC idle state or the RRC inactive state.

[0201] The terminal device in the RRC idle state receives CN-initiated paging, and the terminal device in the RRC inactive state receives RAN-initiated paging. In these two cases, the format of the paging message can be the same.

[0202] When the terminal device is in the RRC idle state, if the terminal device identifier matches one of the terminal device identifiers (eg, UE identifier, UE-identity) in the paging list (paging record), the terminal device reports its terminal device identifier to its upper layer.

[0203] When the terminal device is in the RRC inactive state, if the inactive RNTI (I-RNTI) of the terminal device matches one of the terminal device identifiers (such as UE identifier, UE-identity) in the paging list, then the RRC connection process is initialized, and the I-RNTI is carried in the UE-Identity in the Paging message to wake up the terminal device in the inactive state. Otherwise, if it is the identifier corresponding to the terminal device, the terminal device reports the terminal device identifier to its upper layer, and the terminal device enters the RRC idle state.

[0204] After receiving the paging system message update indication, the terminal device can receive a new system message in the next modification period.

[0205] In the U2N relay scenario, for example Figure 1 In the scenario shown, if the remote UE is in the RRC idle state or inactive state, the remote UE can monitor the paging message by itself through the Uu interface between the remote UE and the network device (this is only applicable to the remote UE in coverage (IC)), or the relay UE can monitor the paging message of the remote UE instead. These two ways of monitoring the paging message can be configured by the network device, and the embodiments of the present application are not limited to this.

[0206] When the relay UE monitors the paging message of the remote UE instead, the relay UE needs to know that the remote UE has entered the idle state or the inactive state. Then the relay UE can monitor the paging message at the PO of the remote UE, or can monitor the paging message at the PO of the relay UE, without limitation.

[0207] There is a possible situation that when the network device determines that the remote UE enters the idle state, it will send the RRC connection release message that needs to be sent to the remote UE to the relay UE. The relay UE may not receive or cannot successfully decode the RRC connection release message sent by the network device to the remote UE, then the relay UE will not forward the RRC connection release message sent by the network device to the remote UE, and then the remote UE will not receive the RRC connection release message sent by the network device and will remain in the connected state. At this time, there is a problem of mismatch in the RRC states of the network device, relay UE and remote UE.

[0208] This will lead to the following problems:

[0209] When the network device configures the remote UE to monitor PO, the remote UE will not monitor the paging message due to the mismatch between the RRC state of the remote UE and the network device;

[0210] When the network device configures the relay UE to monitor the paging message of the remote UE, since the relay UE does not know that the network device considers the remote UE to be in an idle state, the relay UE does not know that it needs to monitor the paging message for the remote UE.

[0211] In view of this, an embodiment of the present application provides a communication method, in which the relay UE can be instructed to listen to the paging message of the remote UE, so that the relay UE can determine that the RRC state of the remote UE is the RRC idle state or the RRC inactive state. Further, the relay UE can instruct the remote UE to enter the RRC idle state or the RRC inactive state, thereby achieving alignment of the RRC state of the remote UE among the network device, the relay UE, and the remote UE, making it easier for the relay UE to determine whether it is necessary to listen to the paging message for the remote UE, or for the remote UE to determine whether it is necessary to listen to the paging message.

[0212] The communication method provided in the embodiments of the present application is described below with reference to the accompanying drawings.

[0213] The technical solution of the present application can be applied to wireless communication systems, for example, Figure 1 The communication system shown in . The communication device in the wireless communication system may include a network device, a first terminal device and a second terminal device, and each communication device may have a wireless communication connection relationship. The network device in the communication device may correspond to Figure 1 The network device shown in the figure may also be a chip configured in the network device; the first terminal device in the communication device may correspond to Figure 1 The remote terminal device shown in may also be a chip configured in the remote terminal device; the second terminal device in the communication device may correspond to Figure 1 The relay terminal device shown in may also be a chip configured in the relay terminal device.

[0214] It should be understood that in the embodiments shown below, "pre-definition" can be achieved by pre-saving corresponding codes, tables or other methods that can be used to indicate relevant information in devices (for example, including terminal devices and network devices), or pre-configuring network devices, etc. This application does not limit its specific implementation method.

[0215] It should also be understood that the "storage" involved in the embodiments of the present application may refer to storage in one or more memories. The one or more memories may be separately set or integrated in an encoder or decoder, a processor, or a communication device. The one or more memories may also be partially separately set and partially integrated in a decoder, a processor, or a communication device. The type of memory may be any form of storage medium, and the present application is not limited thereto.

[0216] It should also be understood that the "protocol" in the embodiments of the present application may refer to a standard protocol in the communication field, for example, it may include an LTE protocol, an NR protocol, and related protocols used in future communication systems, and the present application does not limit this.

[0217] Below, without loss of generality, firstly, the communication process of a pair of first terminal devices and second terminal devices (i.e., relay terminal devices and remote terminal devices) is taken as an example to describe the embodiments of the present application in detail. It can be understood that any pair of first terminal devices and second terminal devices (i.e., relay terminal devices and remote terminal devices) in a wireless communication system, or chips configured in a pair of first terminal devices and second terminal devices (i.e., relay terminal devices and remote terminal devices) can communicate based on the same method, and any network device in a wireless communication system or chips configured in a network device can communicate based on the same method, and the present application does not limit this.

[0218] In the embodiment of the present application, the first terminal device can communicate with the network device through the second terminal device, and the first terminal device and the second terminal device can communicate through a side link. As an example, the protocol stack structure between the first terminal device, the second terminal device and the network device can be as follows: Figure 2 The protocol stack structure shown.

[0219] Figure 4 A schematic flow chart of a communication method 400 provided by an embodiment of the present application is shown. In method 400, when the network device releases or suspends the radio resource control RRC connection between the first terminal device and the network device, it can instruct the second terminal device (e.g., relay terminal device, relay UE, etc.) to monitor the paging message for the first terminal device (e.g., remote terminal device, remote UE, etc.). Accordingly, the second terminal device monitors the paging message according to the instruction of the network device, and instructs the first terminal device to enter the RRC idle state or the RRC inactive state. The first terminal device can enter the RRC idle state or the RRC inactive state according to the instruction of the second terminal device.

[0220] Figure 4 The communication method shown in includes steps 401 to 406.

[0221] 401. Optionally, the network device sends a first message, where the first message is used to release or suspend a radio resource control RRC connection between the first terminal device and the network device.

[0222] When the first message is used to release the RRC connection between the first terminal device and the network device, the first message is used to configure the first terminal device to enter an idle state, that is, RRC idle. As an example, the first message at this time may be an RRC connection release message.

[0223] When the first message is used to suspend the RRC connection between the first terminal device and the network device, the first message is used to configure the first terminal device to enter the RRC inactive state. As an example, the first message may be an RRC connection release with suspend message.

[0224] As a possible implementation, when the network device determines that there is no downlink (DL) data / signaling that needs to be sent to the first terminal device, or when no uplink (UL) data / signaling is received from the first terminal device within a first preset time, the network device can determine to release or suspend the RRC connection between the first terminal device and the network device, that is, determine to convert the RRC state of the first terminal device from the RRC connected state to the RRC idle state, or the RRC inactive state. At this time, the network device can execute step 401, that is, send the above-mentioned first message.

[0225] Exemplarily, the first preset duration may be predefined. For example, the first preset duration may be pre-stored in a network device, or the first preset duration may be defined by a protocol, and this application does not impose any limitation on this.

[0226] In the embodiment of the present application, UL data may include, for example, MAC PDU or transport block (TB), and UL signaling may include, for example, RRC message, or MAC CE, etc., such as sidelink UE information (SidelinkUEInformation). DL data may include, for example, MAC PDU or TB, and DL signaling may include, for example, RRC message, or MAC CE, etc., such as RRC reconfiguration message.

[0227] Optionally, the network device may send the first message to the second terminal device.

[0228] In some possible embodiments, when the first message is successfully sent to the second terminal device and is successfully decoded by the second terminal device, the second terminal device can determine, based on the first message, that the RRC state of the first terminal device is an RRCidle state or an RRC inactive state.

[0229] In other possible embodiments, when the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device, the second terminal device cannot determine (i.e., does not know) the RRC state of the first terminal device because it cannot read the RRC message sent by the network device to the first terminal device.

[0230] As a possible implementation manner, the network device can determine whether the first message is successfully sent to the second terminal device or whether the first message is successfully decoded by the second terminal device by whether a feedback message corresponding to the above-mentioned first message sent by the second terminal device is received.

[0231] For example, when the second terminal device successfully receives and decodes the above-mentioned first message, it can send an acknowledgement (ACK) message to the network device to indicate that the above-mentioned first message is successfully received and decoded; when the second terminal device fails to successfully receive or successfully decode the above-mentioned first message within the second preset time length, it can send a negative acknowledgement (negative acknowledgement) message to the network device to indicate that the above-mentioned first message is not successfully received or successfully decoded.

[0232] Exemplarily, the second preset duration can be predefined. For example, the second preset duration can be pre-stored in the terminal device, or the network device can indicate the second preset duration to the second terminal device in advance, or the second preset duration is defined by a protocol. The embodiments of the present application are not limited to this.

[0233] In some optional embodiments, the second terminal device may determine that the RRC states of the network device and the first terminal device are not aligned.

[0234] As a possible implementation method, if the second terminal device determines that it has not successfully received the first message from the network device, or has not successfully decoded the first message, the second terminal device cannot determine the RRC state of the first terminal device, that is, it can be determined that the RRC states between the network device and the first terminal device are not aligned.

[0235] For example, the network device determines that the first terminal device enters the RRC idle state, but the second terminal device does not receive the RRC connection release message, or does not successfully decode the RRC connection release message, so the second terminal device is uncertain about the RRC state of the first terminal device, while the first terminal device is still in the RRC connected state. At this time, it can be considered that the RRC states of the network device and the first terminal device are not aligned, that is, there is a mismatch in the RRC state.

[0236] Optionally, after step 401, if the network device has downlink data or downlink signaling to send to the first terminal device, the network device may send a paging message for paging the first terminal device.

[0237] 402, the network device sends first indication information, where the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device. The paging message can be used by the network device to page the first terminal device.

[0238] It is understandable that when the second terminal device monitors the paging message for the first terminal device, the RRC state of the first terminal device is the RRC idle state or the RRC inactive state. Therefore, the first indication information is used to indicate that the second terminal device monitors the paging message for the first terminal device, and can also be replaced by: the first indication information is used to indicate that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state, or the first indication information is used to indicate that the RRC state of the first terminal device is converted from the RRC connected state to the RRC idle state or the RRC inactive state.

[0239] In some possible embodiments, the first indication information may include an identifier of the first terminal device. For example, when the second terminal device is connected to multiple terminal devices (i.e., can simultaneously communicate with the multiple terminal devices via a side link), the first indication information may include an identifier of the first terminal device, and at this time, the second terminal device can be instructed to monitor a paging message for the first terminal device among the multiple terminal devices through the identifier of the first terminal device.

[0240] In some possible embodiments, the first indication information may be carried in an RRC message or a media access control (MAC) control element (CE) signaling. As an example, the RRC message may be an RRC reconfiguration message, or other RRC messages, without limitation.

[0241] As a possible implementation method, a field may be defined in an RRC message or in a MAC CE signaling, and the field may be used to indicate whether the second terminal device needs to monitor the paging message instead of the first terminal device. As an example, when the field is 0, it may indicate that the second terminal device does not need to monitor the paging message instead of the first terminal device; when the field is 1, it may indicate that the second terminal device needs to monitor the paging message instead of the first terminal device, or vice versa, without limitation.

[0242] In some possible embodiments, the network device may send the first indication information when sending the first message, for example, at the same time as sending the first message, before sending the first message, or after sending the first message. That is, regardless of whether the network device successfully sends the first message, the first indication information is sent to ensure that the second terminal device can monitor the paging message sent by the network device instead of the first terminal device.

[0243] In some other possible embodiments, the network device may send the above-mentioned first indication information when it is determined that the first message is not successfully sent. For example, the first indication information may be sent to the second terminal device after receiving the NACK message fed back by the second terminal device. In this way, by sending the first indication information when the first message is not successfully sent, the second terminal device can monitor the paging message sent by the network device on behalf of the first terminal device even if it does not receive the first message.

[0244] In some possible embodiments, when the second terminal device is in an RRC connected state, the network device may directly send the above-mentioned first indication information to the second terminal device in the RRC connected state.

[0245] In some other possible embodiments, for example, when the second terminal device is in the RRC idle state or the RRC inactive state, the network device may further send a paging message or an RRC establishment message to the second terminal device before sending the first indication information to the second terminal device, so that the second terminal device enters the RRC connected state from the RRC idle state or the RRC inactive state. After the second terminal device enters the RRC connected state, the network device may send the first indication information to the second terminal device.

[0246] Correspondingly, the second terminal device can receive the above-mentioned first indication information sent by the network device.

[0247] Optionally, the network device may also indicate to the second terminal device whether the first terminal device has entered the RRC idle state or the RRC inactive state. Exemplarily, the network device may add an indication field in a paging message for paging the first terminal device, or in a MAC header of a MAC PDU in which the paging message is located, or in an RRC message to indicate whether the first terminal device has entered the RRC idle state or the RRC inactive state.

[0248] 403. The second terminal device monitors the paging message sent by the network device to the first terminal device.

[0249] After receiving the first indication information, the second terminal device can monitor the paging message sent by the network device to the first terminal device according to the first indication information. For example, the paging message can be monitored on the PO of the first terminal device, or the paging message of the first terminal device can be monitored on the PO of the second terminal device, and this application does not limit this.

[0250] In some possible embodiments, when the first indication information includes an identifier of the first terminal device, the second terminal device may monitor a paging message sent by the network device to the first terminal device according to the identifier of the first terminal device.

[0251] It can be understood that when the second terminal device monitors the paging message sent by the network device to the first terminal device, the second terminal device can determine (or assume) that the RRC state of the first terminal device is RRC idle state or RRC inactive state.

[0252] 404, the second terminal device sends second indication information to the first terminal device, where the second indication information is used to indicate that the first terminal device enters an idle state or a deactivated state. Correspondingly, the first terminal device receives the second indication information.

[0253] As an example, the second terminal device may send the above-mentioned second indication information to the first terminal device through the side link between the second terminal device and the first terminal device. For example, the second indication information is carried in a side link RRC message, or a MACCE, or a MAC header. Alternatively, the second indication information may also be used to instruct the first terminal device to release unlimited link resources, which may be a bearer configuration of an air interface link configuration, for example, a Uu SDAP configuration, and / or a Uu PDCP configuration. Optionally, the second indication information may also instruct the first terminal device to release one or more of the following: SL RLC configuration, MAC configuration, SL bearer configuration, SLLCH configuration, etc.

[0254] It should be noted that the embodiment of the present application does not limit the order of step 403 and step 404. For example, step 403 may be performed before, after, or simultaneously with step 404. In addition, in some embodiments, step 404 may be an optional step, that is, step 404 may not be performed.

[0255] 405. The second terminal device sends a paging message to the first terminal device.

[0256] Specifically, when the second terminal device receives (or listens to, or obtains) a paging message sent by the network device for the first terminal device, the second terminal device can send (or forward) the paging message to the first terminal device. For example, when the second terminal device is at the PO of the first terminal device, or after the second terminal device PO listens to the paging message for the first terminal device, the paging message can be sent (or forwarded) to the first terminal device via the PC5 side link.

[0257] Before step 405, when the second terminal device has not received the indication information sent by the first terminal device to indicate the RRC state, the second terminal device cannot determine the RRC state of the first terminal device.

[0258] In some optional embodiments, for example, after step 404, or simultaneously with step 404, or before step 405, or after step 405, or simultaneously with step 405, the second terminal device may send a third indication message to the first terminal device, where the third indication message is used to instruct the first terminal device to release the first configuration, where the first configuration may be a side link configuration between the second terminal device and the first terminal device (e.g., a PC5 configuration), and / or an air interface link configuration between the first terminal device and the network device (e.g., an NR air interface configuration).

[0259] The third indication information may be used to trigger the sidelink release process and / or the air interface link release process. Exemplarily, the third indication information may be carried in a PC5 RRC release message, which is not limited in the present application.

[0260] Exemplarily, PC5 configuration may include sidelink radio bearer (SLRB) configuration, MAC configuration, radio link control (RLC) bearer configuration, and RLC configuration, etc., without limitation.

[0261] In some optional embodiments, the second indication information and the third indication information may be sent in the same message, or may be sent separately in two different messages, which is not limited in the embodiments of the present application.

[0262] In some optional embodiments, the second terminal device may not execute step 404, but may send third indication information to the first terminal device.

[0263] Therefore, in an embodiment of the present application, by instructing the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device, the first terminal device can release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device when entering the RRC idle state or the RRC inactive state.

[0264] Optionally, the second terminal device may determine whether the first terminal device enters the RRC idle state or the RRC inactive state according to the instruction of the network device. In addition, the second terminal device may further indicate to the first terminal device that the first terminal device enters the RRC idle state or the RRC inactive state. For example, the second terminal device may add an indication field in the MAC header of the MAC PDU where the paging message is located, or in the RRC message, or in the SCI to indicate whether the second terminal device enters the RRC idle state or the RRC inactive state.

[0265] In some optional embodiments, when in step 405, i.e. before the second terminal device sends a paging message to the first terminal device, the second terminal device has triggered the sidelink release process, then before executing step 405, the second terminal device also needs to establish or re-establish the sidelink in order to send the paging message through the established or re-established sidelink.

[0266] 406. The first terminal device enters an idle state or a deactivated state.

[0267] As an example, the first terminal device may enter the RRCidle state or the RRC inactive state after receiving the above-mentioned second indication information. Exemplarily, when the second indication information is used to instruct the first terminal device to enter the RRCidle state, the first terminal device enters the RRC idle state and performs the behavior of entering the idle state, including but not limited to resetting MAC, stopping the running timer, discarding the UE inactive state context, etc. When the second indication information is used to instruct the first terminal device to enter the RRC inactive state, the first terminal device enters the RRC inactive state.

[0268] Optionally, after receiving the second indication information, the first terminal device may also release the side link configuration (for example, PC5 link configuration) between the second terminal device and the first terminal device, and / or the air interface link configuration (for example, NR air interface configuration) between the first terminal device and the network device. This application does not limit this.

[0269] As another example, the first terminal device may enter the RRC idle state or the RRC inactive state after receiving the paging message forwarded by the second terminal device in step 405. At this time, the paging message may also be used to instruct the first terminal device to enter the RRC idle state or the RRC inactive state.

[0270] Optionally, after receiving the paging message, the first terminal device may also release the side link configuration (e.g., PC5 link configuration) between the second terminal device and the first terminal device, and / or the air interface link configuration (e.g., NR air interface configuration) between the first terminal device and the network device. This application does not limit this.

[0271] As another example, after receiving the third indication information, the first terminal device may release the sidelink configuration (e.g., PC5 link configuration) between the second terminal device and the first terminal device, and / or the air interface link configuration (e.g., NR air interface configuration) between the first terminal device and the network device. Optionally, the first terminal device may enter the RRCidle state or the RRC inactive state at this time.

[0272] As an example, the behavior of the first terminal device entering the RRC idle state or the RRC inactive state may specifically include resetting the MAC configuration, releasing wireless resources, instructing the upper layer to release the RRC connection and the release cause (release cause), etc., without limitation.

[0273] In the case where the side link configuration (eg, RLC configuration, or MAC configuration) of the first terminal device is provided by a network device, the side link configuration is released while (or after) the first terminal device enters the RRC idle state or the RRC inactive state.

[0274] When the sidelink configuration of the first terminal device (such as RLC configuration or MAC configuration) is provided by the network device and the first terminal device configures the sidelink for the second terminal device through the PC5 sidelink, the first terminal device releases the sidelink configuration at the same time (or after) it enters the RRC idle state or the RRC inactive state, and initiates a PC5RRC process, such as RRC establishment / recovery, or RRC reconfiguration process, to notify the second terminal device to release the sidelink configuration.

[0275] Optionally, when the first terminal device receives a paging message forwarded by the second terminal device and enters the RRC idle state or the RRC inactive state, it can initiate an RRC establishment / recovery process with the network device. Specifically, the first terminal device can release the previous old air interface link configuration by entering the RRC idle state or the RRC inactive state, and initiate an RRC establishment / recovery process with the network device according to the paging message, establish or restore the RRC connection, and realize the reconfiguration of the RRC link.

[0276] In some optional embodiments, when the RRC state of the first terminal device is converted from an RRC connected state to an RRC idle state or an RRC inactive state, the first terminal device may also send the above-mentioned first indication information to the second terminal device to indicate to the second terminal device that the RRC state of the first terminal device is an RRC idle state or an RRC inactive state, or to indicate that the RRC state of the first terminal device is converted from an RRC connected state to an RRC idle state or an RRC inactive state, or to instruct the second terminal device to listen to paging messages sent by a network device.

[0277] Exemplarily, when the RRC state of the first terminal device is converted from the RRC connected state to the RRC idle state, the first indication information is used to indicate that the RRC state of the first terminal device is the RRC idle state, or to indicate that the RRC state of the first terminal device is converted from the RRC connected state to the RRC idle state. When the RRC state of the first terminal device is converted from the RRC connected state to the RRC inactive state, the first indication information is used to indicate that the RRC state of the first terminal device is the RRC inactive state, or to indicate that the RRC state of the first terminal device is converted from the RRC connected state to the RRC inactive state.

[0278] Optionally, at least one of the first terminal device and the network device may send the first indication information to the second terminal device. For example, when the first terminal device sends the first indication information to the second terminal device, step 402 may not be performed, or the second terminal device does not successfully receive or decode the message carrying the first indication information sent by the network device. For another example, when the network device sends the first indication information to the second terminal device, the first terminal device may not send the first indication information to the second terminal device, or the second terminal device does not successfully receive or decode the message carrying the first indication information sent by the first terminal device.

[0279] In some possible embodiments, for example, when the second terminal device receives the first indication information from the first terminal device and does not receive the first indication information from the network device, the second terminal device may also indicate to the network device that the RRC state of the first terminal device is changed from the RRC connected state to the RRC idle state or the RRC inactive state.

[0280] As a possible implementation method, the first terminal device can determine that the current RRC state is converted from the RRC connected state to the RRC idle state, or the RRC inactive state when there is currently no data or signaling that needs to be sent to the network device, or when no data or signaling sent by the network device is received within a third preset time period. This application is not limited to this.

[0281] Exemplarily, the third preset duration can be predefined. For example, the third preset duration can be pre-stored in the terminal device, or the network device can indicate the third preset duration to the second terminal device in advance, or the third preset duration is defined by the protocol, or the network configures the third preset duration through signaling. The embodiments of the present application are not limited to this.

[0282] As a possible implementation manner, the first terminal device may send the first indication information to the second terminal device via a side link (eg, a PC5 link) between the first terminal device and the second terminal device, which is not limited in the present application.

[0283] Therefore, the embodiment of the present application can enable the second terminal device to determine that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state by instructing the second terminal device to monitor the paging message of the first terminal device, thereby determining that it is necessary to monitor the paging message for the first terminal device. Further, the second terminal device can instruct the first terminal device to enter the RRC idle state or the RRC inactive state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0284] Exemplarily, an embodiment of the present application is applicable to a scenario in which the second terminal device fails to successfully receive or decode a first message for releasing or suspending the RRC connection between the first terminal device and the network device. At this time, the second terminal device fails to successfully receive or decode the first message and therefore cannot determine the RRC state of the first terminal device. In this case, once the second terminal device receives an indication to monitor the paging message of the first terminal device, it can be determined that the first terminal device is in the RRC idle state or the RRC inactive state, and then the first terminal device can be instructed to enter the RRC idle state or the inactive state, so that the network device, the second terminal device and the first terminal device all perceive that the first terminal device is in the RRC idle state or the inactive state, thereby facilitating the alignment of the RRC state of the first terminal device by the network device, the first terminal device and the second terminal device.

[0285] When the network device, the first terminal device, and the second terminal device align the RRC state of the first terminal device, more efficient data transmission can be achieved between the network device, the first terminal device, and the second terminal device. For example, the second terminal device can determine that the first terminal device monitors paging messages or receives downlink data / signaling transmissions, and the second terminal device receives and forwards paging messages or data from the network device.

[0286] Figure 5 A schematic flow chart of another communication method 500 provided by an embodiment of the present application is shown. In method 500, when it is determined that no data or signaling of the first terminal device is received / sent for a first period of time, it can be determined that the first terminal device enters an idle state or a deactivated state. As an example, method 500 can be executed by a second terminal device (or a chip in the second terminal device), or by a first terminal device (or a chip in the first terminal device), or a network device (or a chip in a network device), and the present application does not limit this. Figure 5 As shown, method 500 includes steps 510 and 520 .

[0287] 510, determining that no data or signaling of the first terminal device is received or sent during the first time period.

[0288] In some embodiments, it can be determined that no data or signaling of the first terminal device is received and no data or signaling of the first terminal device is sent during the first time period.

[0289] As an example, when method 500 is executed by the second terminal device, the second terminal device can determine that no DL data / signaling sent by the network device that needs to be forwarded to the first terminal device is received within the first time period, and no UL data / signaling sent by the first terminal device that needs to be forwarded to the network device is received within the first time period.

[0290] As an example, when method 500 is executed by a first terminal device, the first terminal device may determine that there is no UL data / signaling that needs to be sent to the network device in the first time period, and no DL data / signaling sent by the second terminal device from the network device is received in the first time period.

[0291] As an example, when method 500 is executed by a network device, the network device may determine that no DL data / signaling needs to be sent to the first terminal device during the first time period, and no UL data / signaling is received from the first terminal device during the first time period.

[0292] Exemplarily, in an embodiment of the present application, the first duration can be predefined. For example, the first duration can be pre-stored in the network device, the first terminal device or the second terminal device, or the first duration can be defined by a protocol, or the network device can configure the first duration, or the second terminal device can configure the first duration, or the first terminal device can configure the first duration. The present application does not limit this.

[0293] As an example, when the first duration is configured by a network device, the network device may indicate (for example, by sending indication information) the first duration to the first terminal device or the second terminal device, or the network device may indicate the first duration to the second terminal device, and further the second terminal device indicates the first duration to the first terminal device. This application is not limited to this.

[0294] As an example, when the first duration is configured by the second terminal device, the second terminal device may indicate (for example, by sending indication information) the first duration to the network device or the first terminal device.

[0295] As an example, when the first duration is configured by the first terminal device, the first terminal device can indicate the first duration to the network device or the second terminal device (for example, by sending indication information), or the first terminal device can indicate the first duration to the second terminal device, and further, the second terminal device can indicate the first duration to the network device. This application is not limited to this.

[0296] As a possible implementation, a timer, such as a data inactivity timer, may be set to determine whether data or signaling of the first terminal device is not received or sent for the first time period. For example, the timer may be set to time out when the timer reaches the first time period. Optionally, the timer may be started when data or signaling is received or sent. When the timer times out, it may be determined that data or signaling is not received or sent for the first time period.

[0297] In some embodiments, a timer may be set inside the second terminal device, and the timer may be dedicated to forwarding data. At this time, data / signaling of one or more first terminal devices that can perform sidelink communication with the second terminal device may trigger the timer.

[0298] In some embodiments, when the second terminal device is capable of side link communication with at least two first terminal devices, the second terminal device can define, maintain or run the above-mentioned timer for each first terminal device respectively. At this time, the data / signaling of each first terminal device can trigger the timer corresponding to the first terminal device.

[0299] In some embodiments, there may be only one timer inside the second terminal device, which can be used for air interface data (e.g., Uu data) and forwarding data. At this time, the data / signaling of one or more first terminal devices that can communicate with the second terminal device via a side link, as well as the data / signaling of the second terminal device, can trigger the timer.

[0300] As a specific example, the network device can define a timer (e.g., datainactivity timer) for the PC5 MAC of the first terminal device. The MAC of the second terminal device is a PC5 MAC entity, there is no end-to-end MAC between the network device, and the MAC receives a MAC service data unit (SDU) from a sidelink logical channel (SLLCH), such as a sidelink control channel (SCCH) and a sidelink traffic channel (STCH), or sends a MAC SDU corresponding to the SLLCH.

[0301] For the timer of the first terminal device, the timer can be started or restarted when the first terminal device sends a MAC SDU corresponding to the SCCH or STCH dedicated to forwarding, and the timer can be started or restarted when the first terminal device receives a MAC SDU from the SCCH or SRCH corresponding to the dedicated forwarding. In this way, when the first terminal device neither sends a MAC SDU of the SCCH or STCH nor receives a MAC SDU from the SCCH or SRCH within the first time period, the timer times out.

[0302] As an example, the network device defines the first duration when defining the timer on the first terminal device side. Alternatively, the first terminal device may pre-store the first duration, or the first duration may be defined by a protocol, or the network device may indicate the first duration, which is not limited in this application.

[0303] It should be noted that the above description is based on the example of setting a timer on the first terminal device side. The timers on the second terminal device side and the network device side can refer to the description of the timer on the first terminal device side, or some simple adaptation may be required, which is all within the protection scope of the embodiments of the present application.

[0304] 520, determine whether the first terminal device enters an idle state or a deactivated state.

[0305] As an example, when the second terminal device determines that no data or signaling of the first terminal device is received or sent for a first period of time, the second terminal device may determine that the first terminal device enters the RRC idle state or the RRC inactive state. Optionally, the data or signaling is data or signaling that needs to be forwarded by the second terminal device to the network device or other terminal devices.

[0306] As an example, when the first terminal device determines that no data or signaling of the first terminal device has been received or sent for a first period of time, the first terminal device may determine to enter an RRC idle state or an RRC inactive state.

[0307] As an example, when the network device determines that no data or signaling of the first terminal device is received or sent within a first period of time, the network device can determine that the first terminal device enters the RRC idle state or the RRC inactive state.

[0308] In some optional embodiments, when the second terminal device determines that the first terminal device enters an idle state or a deactivated state, the second terminal device may determine to monitor a paging message for the first terminal device.

[0309] Optionally, the second terminal device may also send a second indication message to the network device or the first terminal device, where the second indication message is used to indicate that the first terminal device enters the RRC idle state or the RRC inactive state. In this way, by indicating to the network device that the first terminal device enters the idle state or the deactivated state, it helps to align the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0310] In some optional embodiments, when the first terminal device determines to enter an idle state or a deactivated state, the first terminal device may send second indication information to the network device or the second terminal device, and the second indication information is used to instruct the first terminal device to enter an RRC idle state or an RRC inactive state.

[0311] In some optional embodiments, when the network device determines that the first terminal device enters an idle state or a deactivated state, the network device may send second indication information to the second terminal device or the second terminal device, and the second indication information is used to indicate that the first terminal device enters an RRC idle state or an RRC inactive state.

[0312] In some optional embodiments, when the first terminal device determines to enter the connected state, the first terminal device may send an indication message to the second terminal device or the network device, and the indication message is used to indicate that the first terminal device enters the RRC connected state. After receiving the indication message, the second terminal device stops monitoring the paging message for the first terminal device. Here, this step can be used in combination with other steps in the embodiment, or used as an independent method, without limitation.

[0313] It should be noted that in an embodiment of the present application, when it is determined that the first terminal device enters the RRC idle state, the second indication information is used to instruct the first terminal device to enter the RRC idle state; when it is determined that the first terminal device enters the RRC inactive state, the second indication information is used to instruct the first terminal device to enter the RRC inactive state.

[0314] Therefore, in an embodiment of the present application, at least one of the network device, the first terminal device, and the second terminal device can determine that the first terminal device has entered an idle state or a deactivated state by determining that no data or signaling of the first terminal device has been received or sent for a first period of time, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device. For example, the network device, the first terminal device, and the second terminal device all sense that the first terminal device is in an RRC idle state, inactive state, or connected state.

[0315] When the network device, the first terminal device, and the second terminal device align the RRC state of the first terminal device, more efficient data transmission can be achieved between the network device, the first terminal device, and the second terminal device. For example, the second terminal device can determine that the first terminal device monitors paging messages or receives downlink data / signaling transmissions, and the second terminal device receives and forwards paging messages or data from the network device.

[0316] In some embodiments, the first terminal device may determine to enter the RRC idle state or the RRC inactive state when no UL data / signaling is sent or no DL data / signaling is received for a first time period. As an example, a timer may be set on the first terminal device side to determine whether the first terminal device has not sent UL data / signaling or received DL data / signaling for a first time period. At this time, the first terminal device may determine to enter the RRC idle state or the RRC inactive state when no UL data / signaling is sent or no DL data / signaling is received for a first time period. Figure 6 The method 600 shown in, or Figure 7 The method 700 shown in enables the second terminal device to determine the RRC state of the first terminal device.

[0317] See also Figure 6, shows a schematic flow chart of another communication method 600 provided by an embodiment of the present application. In method 600, when the first terminal device determines to enter the RRC idle state or the RRC inactive state, it can indicate the RRC state of the first terminal device to the second terminal device, so that the second terminal device determines the RRC state of the first terminal device.

[0318] It should be understood that Figure 6 The steps or operations of the communication method are shown, but these steps or operations are only examples. The embodiment of the present application may also perform other operations or Figure 6 In addition, Figure 6 The steps in Figure 6 are executed in a different order than the ones presented, and may not be executed Figure 6 All operations in Figure 6 As shown, the communication method may include steps 601 to 610.

[0319] 601, optionally, the network device sends DL data / signaling to the second terminal device. Correspondingly, the second terminal device receives the DL data / signaling. Here, the DL data / signaling is the DL data / signaling sent by the network device and needs to be forwarded to the first terminal device.

[0320] 602. Optionally, the second terminal device fails to obtain (or select) SL resources in a timely manner.

[0321] As an example, when the second terminal device does not select a SL resource within the second time range, or the second terminal device does not select a resource that meets the delay requirement, or the second terminal device does not obtain a SL resource scheduled by the base station within the second time range, or the SL resource obtained by the second terminal device is not available within the second time range, or the second terminal device does not have an available SL resource within the second time range, it can be determined that the second terminal device did not select a SL resource in time. The SL resource may be, for example, a mode 2 SL resource, without limitation.

[0322] Exemplarily, in an embodiment of the present application, the second duration can be predefined. For example, the second duration can be pre-stored in the second terminal device, or the second duration can be defined by a protocol, or the network device can indicate the second duration to the second terminal device. The present application does not limit this.

[0323] Optionally, in step 603, the network device sends fourth indication information to the second terminal device. The fourth indication information is used to indicate the first duration, and if the timer does not receive or send data / signaling of the first terminal device during the first duration, the timer times out. After the second terminal device receives the fourth indication information, it can execute step 604 to send the fourth indication information to the first terminal device.

[0324] Or, alternatively, steps 603 and 604 may not be performed, and the first terminal device may determine the first duration.

[0325] Or, alternatively, the second terminal device may determine the first duration, and after determining the first duration, execute step 604, that is, send fourth indication information to the first terminal device to indicate the first duration.

[0326] It should be noted that steps 603 and 604 may occur at any time before step 605, for example, before step 601 or simultaneously with step 601, or before step 602 or simultaneously with step 602, or after step 602, and this application does not limit this.

[0327] 605. The timer on the first terminal device times out.

[0328] As an example, the first terminal device may start or restart the timer when receiving DL data / signaling forwarded from the network device by the second terminal device, or when sending UL data / signaling to the network device to the second terminal device. When the first terminal device does not receive DL data / signaling, or send UL data / signaling within the first time period after starting or restarting the timer, the timer on the first terminal device side times out.

[0329] When the timer on the first terminal device side times out, the first terminal device can determine that it has entered the RRC idle state or the RRC inactive state from the RRC connected state.

[0330] It should be noted that since the second terminal device failed to select the SL resources in time, the DL data / signaling sent by the network device to the first terminal device was not successfully sent to the first terminal device, which in turn caused the timer on the first terminal device side to time out. At this time, the network device can still consider that the first terminal device is in the RRC connected state. The second terminal device cannot determine the RRC state of the first terminal device at this time, resulting in a mismatch of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0331] 606, the first terminal device sends second indication information to the second terminal device, where the second indication information is used to indicate that the first terminal device enters the RRC idle state or the RRC inactive state. Correspondingly, the second terminal device receives the second indication information.

[0332] Exemplarily, the second indication information may be carried in a PC5 RRC message, that is, the first terminal device may indicate to the second terminal device through a PC5RRC message that it enters an RRC idle state or an RRC inactive state. Alternatively, the second indication may also be carried in a MAC CE or sidelink control information (SCI).

[0333] 607. The second terminal device monitors the paging message of the first terminal device.

[0334] As an example, the second terminal device may determine that the first terminal device enters the RRC idle state or the RRC inactive state according to the second indication information. At this time, the second terminal device may monitor the paging message sent by the network device for the first terminal device.

[0335] Therefore, the embodiment of the present application indicates to the second terminal device through the first terminal device that the first terminal device enters the RRC idle state or the inactive state, so that the second terminal device can determine that the RRC state of the first terminal device is the RRCidle state or the RRC inactive state, so that the first terminal device can monitor the paging message sent by the network device, which helps to achieve the alignment of the RRC state of the first terminal device among the network device, the first terminal device and the second terminal device. For example, the network device, the first terminal device and the second terminal device all sense that the first terminal device is in the RRC idle state or the inactive state or the connected state.

[0336] When the network device, the first terminal device, and the second terminal device align the RRC state of the first terminal device, more efficient data transmission can be achieved between the network device, the first terminal device, and the second terminal device. For example, the second terminal device can determine that the first terminal device monitors paging messages or receives downlink data / signaling transmissions, and the second terminal device receives and forwards paging messages or data from the network device.

[0337] Optionally, 608, the second terminal device sends a second indication message to the network device to indicate that the first terminal device enters the RRC idle state or the RRC inactive state. Alternatively, the first terminal device may also directly send a second indication message to the network device to indicate that the first terminal device enters the RRC idle state or the RRC inactive state.

[0338] Correspondingly, the network device can receive the second indication information and can determine, based on the second indication information, that the first terminal device enters the RRC idle state or the RRC inactive state. After the network device determines that the first terminal device enters the RRC idle state or the RRC inactive state, if there is DL data / signaling that needs to be sent to the first terminal device, a paging message for paging the first terminal device can be sent.

[0339] Therefore, the embodiment of the present application indicates to the network device through the first terminal device or the second terminal device that the first terminal device enters the RRC idle state or the RRC inactive state, so that the network device can determine that the RRC state of the first terminal device is the RRC idle state or the RRC inactive state, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device. For example, the network device, the first terminal device, and the second terminal device all perceive that the first terminal device is in the RRC idle state or the inactive state or the connected state.

[0340] 609, the second terminal device sends DL data / signaling to the first terminal device. Correspondingly, the first terminal device receives the DL data / signaling. Here, the DL data / signaling is the DL data / signaling received by the second terminal device from the network device in step 601.

[0341] Exemplarily, when the second terminal device selects the SL resource, the above-mentioned DL data / signaling can be sent to the first terminal device on the selected SL resource.

[0342] In some embodiments, if the second terminal device does not select the SL resource, the second terminal device will not send the above DL data / signaling to the first terminal device.

[0343] 610. The first terminal device triggers or initiates the RRC establishment / recovery process.

[0344] Exemplarily, the first terminal device may trigger or initiate an RRC establishment / recovery process after receiving the above-mentioned DL data / signaling. It should be noted that the DL data / signaling does not include an RRC release message. That is, when the first terminal device receives the RRC release message in step 609, step 610 is not executed.

[0345] In response to the RRC establishment / recovery process initiated by the first terminal device, the network device can establish an RRC connection with the first terminal device. At this time, the network device, the first terminal device and the second terminal device can all perceive that the first terminal device is in the RRC connected state.

[0346] See also Figure 7 , shows a schematic flow chart of another communication method 700 provided by an embodiment of the present application. In method 600, the same timer as that of the first terminal device can be configured on the second terminal device side, so that the second terminal device determines the RRC state of the first terminal device.

[0347] It should be understood that Figure 7 The steps or operations of the communication method are shown, but these steps or operations are only examples. The embodiment of the present application may also perform other operations or Figure 7 In addition, Figure 7 The steps in Figure 7 are executed in a different order than the ones presented, and may not be executed Figure 7 All operations in Figure 6 As shown, the communication method may include steps 701 to 710.

[0348] 701, the network device sends DL data / signaling to the second terminal device. Correspondingly, the second terminal device receives the DL data / signaling.

[0349] 702. The second terminal device fails to obtain SL resources in time.

[0350] Specifically, steps 701 and 702 can be found in Figure 6 The description of steps 601 and 602 in the above description will not be repeated here.

[0351] Optionally, at 703, the network device sends fourth indication information to the second terminal device. The fourth indication information is used to indicate the first duration, and if the timer does not receive or send data / signaling of the first terminal device during the first duration, the timer times out. After the second terminal device receives the fourth indication information, it can execute step 704 to send the fourth indication information to the first terminal device.

[0352] Alternatively, step 703 may not be performed, but the second terminal device may determine the first duration. Optionally, the second terminal device may perform step 704, that is, after determining the first duration, indicate fourth indication information to the first terminal device.

[0353] Or, alternatively, the first terminal device may determine the first duration, and after determining the first duration, send fourth indication information to the second terminal device to indicate the first duration.

[0354] It should be noted that steps 703 and 704 may occur at any time before step 705, for example, before step 701 or simultaneously with step 701, or before step 702 or simultaneously with step 702, or after step 702, and this application does not limit this.

[0355] 705. The timer on the second terminal device side times out.

[0356] As an example, the second terminal device may start or restart the timer when receiving DL data / signaling corresponding to the first terminal device sent by the network device (e.g., step 601), or forwarding DL data / signaling sent by the network device to the first terminal device, or receiving UL data / signaling sent by the first terminal device that needs to be sent to the network device, or forwarding UL data or signaling sent by the first terminal device to the network device. When the second terminal device does not receive or send data / signaling corresponding to the first terminal device within the first time period after starting or restarting the timer, the timer on the second terminal device side times out.

[0357] When the second terminal device determines that the timer corresponding to the first terminal device on the second terminal device side has expired, the second terminal device can confirm that the first terminal device has entered the RRC idle state, or the RRC inactive state. At this time, the second terminal device can monitor the paging message sent by the network device for the first terminal device. Optionally, the second terminal device can send an indication message to the first terminal device, and the indication message is used to instruct the second terminal device to determine the RRC state of the first terminal device as the RRC idle state, or the RRC inactive state. After the first terminal device receives the indication message, when there is valid data (available data) or there is data / signaling that needs to be forwarded to the network device through the second terminal device, it sends or triggers the RRC connection establishment / recovery process.

[0358] In some optional embodiments, when the second terminal device communicates with multiple remote terminal devices via a side link, multiple timers may be configured on the second terminal device side, and each timer may correspond to a remote terminal device. In this way, when a timer times out, the second terminal device may determine that the remote terminal device corresponding to the timer enters the RRCidle state or the RRC inactive state, and may then monitor the paging message sent by the network device for the remote terminal device.

[0359] 706. The timer on the first terminal device times out.

[0360] As an example, the first terminal device may start or restart the timer when receiving DL data / signaling forwarded from the network device by the second terminal device, or when sending UL data / signaling to the network device to the second terminal device. When the first terminal device does not receive DL data / signaling, or send UL data / signaling within the first time period after starting or restarting the timer, the timer on the first terminal device side times out.

[0361] When the timer on the first terminal device side times out, the first terminal device can determine that it has entered the RRC idle state or the RRC inactive state from the RRC connected state.

[0362] It should be noted that when both the first terminal device side and the second terminal device side are configured with timers, the timer on the first terminal device side and the timer on the second terminal device side can be called a timer pair, and the two timers in a timer pair can be configured or predefined with the same duration. In some embodiments, the timer on the first terminal device side and the timer on the second terminal device side can time out at different times, respectively, which is not limited in the embodiments of the present application.

[0363] It should be noted that, since the second terminal device did not select the SL resources in time, the DL data / signaling sent by the network device to the first terminal device was not successfully sent to the first terminal device, which in turn caused the timer on the first terminal device side to time out. At this time, if the timer is not set on the second terminal device side, the second terminal device cannot determine the RRC state of the first terminal device, and the network device can still believe that the first terminal device is in the RRC connected state, resulting in a mismatch of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device. When a timer is set on the second terminal device side, the second terminal device can determine that the first terminal device enters the RRC idle state or the RRC inactive state when the timer on the second terminal device side times out, thereby helping to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device.

[0364] When the network device, the first terminal device, and the second terminal device align the RRC state of the first terminal device, more efficient data transmission can be achieved between the network device, the first terminal device, and the second terminal device. For example, the second terminal device can determine that the first terminal device monitors paging messages or receives downlink data / signaling transmissions, and the second terminal device receives and forwards paging messages or data from the network device.

[0365] 707. The second terminal device monitors the paging message of the first terminal device.

[0366] As an example, the second terminal device may determine that the first terminal device enters the RRC idle state or the RRC inactive state when a timer on the second terminal device side times out. At this time, the second terminal device may monitor the paging message sent by the network device for the first terminal device.

[0367] Therefore, in an embodiment of the present application, the second terminal device can determine that the first terminal device has entered the RRC idle state or inactive state when the set timer expires, so that the second terminal device can monitor the paging message sent by the network device for the first terminal device, which helps to achieve alignment of the RRC state of the first terminal device among the network device, the first terminal device, and the second terminal device. For example, the network device, the first terminal device, and the second terminal device all sense that the first terminal device is in the RRC idle state, inactive state, or connected state.

[0368] Optionally, 708, the second terminal device sends a second indication message to the network device to indicate that the first terminal device enters the RRC idle state or the RRC inactive state. Alternatively, the first terminal device may also directly send a second indication message to the network device to indicate that the first terminal device enters the RRC idle state or the RRC inactive state.

[0369] 709, the second terminal device sends DL data / signaling to the first terminal device. Correspondingly, the first terminal device receives the DL data / signaling.

[0370] 710. The first terminal device initiates the RRC establishment / recovery process.

[0371] Specifically, steps 708 to 710 can be found in Figure 6 The descriptions of steps 608 to 610 are not repeated here.

[0372] It can be understood that in the above-mentioned embodiments of the present application, the method implemented by the network device can also be implemented by a component (such as a chip or a circuit) that can be used for the network device, the method implemented by the first terminal device can also be implemented by a component (such as a chip or a circuit) that can be used for the first terminal device, and the method implemented by the second terminal device can also be implemented by a component (such as a chip or a circuit) that can be used for the second terminal device.

[0373] According to the above method, Figure 8 A schematic diagram of a wireless communication apparatus 800 provided in accordance with an embodiment of the present application.

[0374] In some embodiments, the device 800 may be a network device, or a chip or circuit, such as a chip or circuit that can be set in a network device. In some embodiments, the device 800 may be a first terminal device, or a chip or circuit, such as a chip or circuit that can be set in a first terminal device. In some embodiments, the device 800 may be a second terminal device, or a chip or circuit, such as a chip or circuit that can be set in a second terminal device.

[0375] The apparatus 800 may include a processing unit 810 (ie, an example of a processor) and a transceiver unit 830 .

[0376] Optionally, the transceiver unit 830 may be implemented by a transceiver or a transceiver-related circuit or an interface circuit.

[0377] Optionally, the device may further include a storage unit 820. In one possible manner, the storage unit 820 is used to store instructions. Optionally, the storage unit may also be used to store data or information. The storage unit 820 may be implemented by a memory.

[0378] In one possible design, the processing unit 810 can be used to execute instructions stored in the storage unit 820 so that the device 800 implements the steps performed by the network device in the above method.

[0379] Furthermore, the processing unit 810, the storage unit 820, and the transceiver unit 830 can communicate with each other through the internal connection path to transmit control and / or data signals. For example, the storage unit 820 is used to store a computer program, and the processing unit 810 can be used to call and run the computer program from the storage unit 820 to control the transceiver unit 830 to receive signals and / or send signals, thereby completing the steps of the network device in the above method.

[0380] In one possible design, the processing unit 810 can be used to execute instructions stored in the storage unit 820 so that the apparatus 800 implements the steps performed by the first terminal device in the above method.

[0381] Furthermore, the processing unit 810, the storage unit 820, and the transceiver unit 830 can communicate with each other through the internal connection path to transmit control and / or data signals. For example, the storage unit 820 is used to store a computer program, and the processing unit 810 can be used to call and run the computer program from the storage unit 820 to control the transceiver unit 830 to receive signals and / or send signals, thereby completing the steps of the first terminal device in the above method.

[0382] In one possible design, the processing unit 810 can be used to execute instructions stored in the storage unit 820 so that the apparatus 800 implements the steps performed by the second terminal device in the above method.

[0383] Furthermore, the processing unit 810, the storage unit 820, and the transceiver unit 830 can communicate with each other through the internal connection path to transmit control and / or data signals. For example, the storage unit 820 is used to store a computer program, and the processing unit 810 can be used to call and run the computer program from the storage unit 820 to control the transceiver unit 830 to receive signals and / or send signals, thereby completing the steps of the second terminal device in the above method.

[0384] The storage unit 820 may be integrated into the processing unit 810 or may be provided separately from the processing unit 810 .

[0385] Optionally, if the apparatus 800 is a communication device, the transceiver unit 830 may include a receiver and a transmitter. The receiver and the transmitter may be the same or different physical entities. When they are the same physical entity, they may be collectively referred to as a transceiver.

[0386] Optionally, if the device 800 is a chip or a circuit, the transceiver unit 830 may include an input interface and an output interface.

[0387] As an implementation, the function of the transceiver unit 830 may be implemented by a transceiver circuit or a dedicated chip for transceiver. The processing unit 810 may be implemented by a dedicated processing chip, a processing circuit, a processing unit or a general chip.

[0388] As another implementation, it is possible to use a general-purpose computer to implement the communication device (e.g., network device, first terminal device, or second terminal device) provided in the embodiment of the present application. That is, the program code that implements the functions of the processing unit 810 and the transceiver unit 830 is stored in the storage unit 820, and the general-purpose processing unit implements the functions of the processing unit 810 and the transceiver unit 830 by executing the code in the storage unit 820.

[0389] In some implementations, when the apparatus 800 is a second terminal device or a chip or circuit disposed in the second terminal device,

[0390] The transceiver unit 830 is configured to receive first indication information, where the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device;

[0391] The processing unit 810 is configured to monitor a paging message sent by a network device to the first terminal device;

[0392] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0393] Optionally, the transceiver unit 830 is further used to send second indication information to the first terminal device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0394] Optionally, the transceiver unit 830 is also used to send third indication information to the first terminal device, and the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

[0395] Optionally, the processing unit 810 is further used to determine that the RRC states between the network device and the first terminal device are not aligned.

[0396] Optionally, the processing unit 810 is specifically configured to:

[0397] determining that a first message from a network device is not successfully received or is not successfully decoded;

[0398] Determine that the RRC states between the network device and the first terminal device are not aligned, wherein the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device.

[0399] Optionally, the first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to instruct the first terminal device to enter an idle state; or

[0400] The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

[0401] Optionally, the first indication information comes from the network device.

[0402] Optionally, the first indication information is carried in an RRC message or MAC CE sent by the network device to the second terminal device.

[0403] Optionally, the first indication information comes from the first terminal device.

[0404] Optionally, the paging message is used by the network device to page the first terminal device.

[0405] Optionally, the first indication information includes an identifier of the first terminal device. The processing unit 810 is specifically configured to monitor a paging message sent by the network device to the first terminal device according to the identifier of the first terminal device.

[0406] Optionally, the transceiver unit 830 is further used to receive a paging message sent by the network device to the first terminal device, and send the paging message to the first terminal device via the side link.

[0407] Optionally, the processing unit 810 is further used to establish or rebuild the side link.

[0408] In some implementations, when the apparatus 800 is a first terminal device or a chip or circuit disposed in the first terminal device,

[0409] The transceiver unit 830 is configured to receive second indication information from the second terminal device, and / or receive a paging message forwarded by the second terminal device, wherein the second indication information is used to indicate that the first terminal device enters an idle state or a deactivated state, and the paging message is used by the network device to page the first terminal device;

[0410] The processing unit 810 is configured to enter an idle state or a deactivated state;

[0411] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0412] Optionally, the transceiver unit 830 is also used to receive third indication information from the second terminal device, and the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

[0413] Optionally, the processing unit 810 is further used to establish or re-establish the side link.

[0414] Optionally, the processing unit 810 is specifically used to initiate an RRC establishment / recovery process with the network device.

[0415] In some embodiments, when the apparatus 800 is a network device or a chip or circuit disposed in a network device,

[0416] The transceiver unit 830 is used to send a first message, where the first message is used to release or suspend a radio resource control RRC connection between the first terminal device and the network device;

[0417] The transceiver unit 830 is further used to send first indication information to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor the paging message for the first terminal device;

[0418] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0419] Optionally, the transceiver unit 830 is specifically used to send the first message to the second terminal device.

[0420] Optionally, the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device.

[0421] Optionally, the transceiver unit 830 is further used to receive negative feedback information, where the negative feedback information is used to indicate that the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device.

[0422] Optionally, the paging message is used by the network device to page the first terminal device.

[0423] Optionally, the first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter an idle state; or

[0424] The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

[0425] Optionally, the first indication information includes an identifier of the first terminal device.

[0426] Optionally, the transceiver unit 830 is further used to send a paging message or an RRC establishment message to the second terminal device.

[0427] Optionally, the first indication information is carried in an RRC message or a media access control element MAC CE.

[0428] In some implementations, when the apparatus 800 is a second terminal device or a chip or circuit disposed in the second terminal device,

[0429] The processing unit 810 is configured to determine that no data or signaling of the first terminal device is received and / or sent during a first time period;

[0430] The processing unit 810 is further configured to determine whether the first terminal device enters an idle state or a deactivated state;

[0431] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0432] Optionally, the processing unit 810 is further configured to monitor a paging message sent by the network device to the first terminal device.

[0433] Optionally, the transceiver unit 830 is used to send second indication information to the network device, and the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0434] Optionally, the transceiver unit 830 is used to receive downlink data and / or signaling from the network device, and forward the downlink data and / or signaling to the first terminal device.

[0435] Optionally, the processing unit 810 is specifically used to determine that the first timer has timed out, and to determine that no data or signaling of the first terminal device has been received or sent within the first time period.

[0436] Optionally, the transceiver unit 830 is used to receive or send data or signaling of the first terminal device, and start or restart the first timer.

[0437] Optionally, the first duration is configured by the network device.

[0438] Optionally, the transceiver unit 830 is used to send fourth indication information to the first terminal device, and the fourth indication information is used to indicate the first duration.

[0439] In some implementations, when the apparatus 800 is a first terminal device or a chip or circuit disposed in the first terminal device,

[0440] The processing unit 810 is configured to determine that no data or signaling is received from the network device during a first time period, and / or that no data or signaling is sent to the network device;

[0441] The processing unit 810 is further configured to determine whether the first terminal device enters an idle state or a deactivated state;

[0442] The first terminal device communicates with the network device via the second terminal device, and the first terminal device communicates with the second terminal device via a side link.

[0443] Optionally, the transceiver unit 830 is used to send second indication information to the second terminal device or the network device, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state.

[0444] Optionally, the transceiver unit 830 is used to receive downlink data and / or signaling from the network device forwarded by the second terminal device;

[0445] The processing unit 810 is further configured to initiate an RRC establishment / recovery process with the network device.

[0446] Optionally, the processing unit 810 is specifically configured to determine, when determining that the second timer has timed out, that no data or signaling has been received from the network device within the first time period, and / or that no data or signaling has been sent to the network device.

[0447] Optionally, the transceiver unit 830 is used to receive data or signaling from a network device, and / or send data or signaling to the network device;

[0448] The processing unit 810 is further configured to start or restart the second timer.

[0449] Optionally, the transceiver unit 830 is further used to receive fourth indication information from the second terminal device, and the fourth indication information is used to indicate the first duration.

[0450] In some embodiments, when the apparatus 800 is a network device or a chip or circuit disposed in a network device,

[0451] The processing unit 810 is configured to determine that no data or signaling of the first terminal device is received and / or sent during a first time period;

[0452] The processing unit 810 is further configured to determine whether the first terminal device enters an idle state or a deactivated state;

[0453] The first terminal device communicates with the network device via the second terminal device, and the first terminal device communicates with the second terminal device via a side link.

[0454] Optionally, the transceiver unit 830 is used to send first indication information to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device.

[0455] Optionally, the transceiver unit 830 is used to send second indication information to the second terminal device, and the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

[0456] Optionally, the processing unit 810 is specifically configured to determine that no data or signaling of the first terminal device is received or sent within the first time period when it is determined that the third timer has timed out.

[0457] Optionally, the processing unit 810 is specifically used to start or restart the third timer when receiving or sending data or signaling of the first terminal device.

[0458] Optionally, the processing unit 810 further determines the first duration.

[0459] Optionally, the transceiver unit 830 is further used to send fourth indication information to the second terminal device, and the fourth indication information is used to indicate the first duration.

[0460] In some implementations, when the apparatus 800 is a second terminal device or a chip or circuit disposed in the second terminal device,

[0461] The transceiver unit 830 is used to receive second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state;

[0462] The processing unit 810 is configured to determine, according to the second indication information, that the first terminal device is in an idle state or a deactivated state;

[0463] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0464] Optionally, the second indication information comes from the first terminal device.

[0465] Optionally, the transceiver unit 830 is further used to send the second indication information to the network device.

[0466] Optionally, the second indication information comes from the network device.

[0467] In some embodiments, when the apparatus 800 is a network device or a chip or circuit disposed in a network device,

[0468] The transceiver unit 830 is used to receive second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state;

[0469] The network device determines, according to the second indication information, that the first terminal device is in an idle state or a deactivated state;

[0470] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0471] Optionally, the second indication information comes from the first terminal device or the second terminal device.

[0472] In some implementations, when the apparatus 800 is a first terminal device or a chip or circuit disposed in the first terminal device,

[0473] The transceiver unit 830 is used to receive second indication information, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state;

[0474] The processing unit 810 is used to enter an idle state or a deactivated state;

[0475] The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

[0476] Optionally, the second indication information comes from the second terminal device or the network device.

[0477] Each unit in the above embodiments may also be referred to as a module, a circuit, or a component.

[0478] Among them, the functions and actions of each module or unit in the device 800 listed above are only exemplary. When the device 800 is configured in or is itself a network device, each module or unit in the device 800 can be used to perform each action or processing process performed by the network device in the above method embodiment. When the device 800 is configured in or is itself a first terminal device, each module or unit in the device 800 can be used to perform each action or processing process performed by the first terminal device in the above method embodiment. When the device 800 is configured in or is itself a second terminal device, each module or unit in the device 800 can be used to perform each action or processing process performed by the second terminal device in the above method embodiment.

[0479] For the concepts, explanations, detailed descriptions and other steps involved in the device 800 and related to the technical solution provided in the embodiment of the present application, please refer to the description of these contents in the aforementioned method or other embodiments, which will not be repeated here.

[0480] Fig. 9 This is a schematic diagram of the structure of a terminal device 900 provided in the present application. The terminal device 900 can execute the actions executed by the terminal device (eg, the first terminal device or the second terminal device) in the above method embodiment.

[0481] For ease of explanation, Fig. 9 Only the main components of the terminal device are shown. Fig. 9 As shown, the terminal device 900 includes a processor, a memory, a control circuit, an antenna, and an input and output device.

[0482] The processor is mainly used to process the communication protocol and communication data, as well as to control the entire terminal device, execute the software program, and process the data of the software program, for example, to support the terminal device to perform the actions described in the above-mentioned transmission precoding matrix indication method embodiment. The memory is mainly used to store software programs and data, for example, to store the codebook described in the above-mentioned embodiment. The control circuit is mainly used for conversion between baseband signals and radio frequency signals and processing of radio frequency signals. The control circuit and the antenna can also be called a transceiver, which is mainly used to send and receive radio frequency signals in the form of electromagnetic waves. Input and output devices, such as touch screens, display screens, keyboards, etc. are mainly used to receive data input by users and output data to users.

[0483] When the terminal device is turned on, the processor can read the software program in the storage unit, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor performs baseband processing on the data to be sent, and outputs the baseband signal to the RF circuit. The RF circuit performs RF processing on the baseband signal and then sends the RF signal outward in the form of electromagnetic waves through the antenna. When data is sent to the terminal device, the RF circuit receives the RF signal through the antenna, converts the RF signal into a baseband signal, and outputs the baseband signal to the processor. The processor converts the baseband signal into data and processes the data.

[0484] Those skilled in the art will appreciate that for ease of description, Fig. 9 Only one memory and processor are shown. In an actual terminal device, there may be multiple processors and memories. The memory may also be referred to as a storage medium or a storage device, etc., which is not limited in the embodiments of the present application.

[0485] For example, the processor may include a baseband processor and a central processing unit. The baseband processor is mainly used to process the communication protocol and communication data, and the central processing unit is mainly used to control the entire terminal device, execute software programs, and process data of the software programs. Fig. 9 The processor in integrates the functions of the baseband processor and the central processing unit. Those skilled in the art will understand that the baseband processor and the central processing unit may also be independent processors, which are interconnected through technologies such as buses. Those skilled in the art will understand that the terminal device may include multiple baseband processors to adapt to different network standards, and the terminal device may include multiple central processing units to enhance its processing capabilities. The various components of the terminal device may be connected through various buses. The baseband processor may also be described as a baseband processing circuit or a baseband processing chip. The central processing unit may also be described as a central processing circuit or a central processing chip. The function of processing the communication protocol and communication data may be built into the processor, or may be stored in the storage unit in the form of a software program, and the processor executes the software program to implement the baseband processing function.

[0486] For example, in the embodiment of the present application, the antenna and the control circuit having the transceiver function may be regarded as the transceiver unit 910 of the terminal device 900, and the processor having the processing function may be regarded as the processing unit 920 of the terminal device 900. Fig. 9 As shown, the terminal device 900 includes a transceiver unit 910 and a processing unit 920. The transceiver unit 910 may also be referred to as a transceiver, a transceiver, a transceiver device, etc. Optionally, a device used to implement a receiving function in the transceiver unit 910 may be regarded as a receiving unit, and a device used to implement a sending function in the transceiver unit 910 may be regarded as a sending unit, that is, the transceiver unit includes a receiving unit and a sending unit. Exemplarily, the receiving unit may also be referred to as a receiver, a receiver, a receiving circuit, etc., and the sending unit may be referred to as a transmitter, a transmitter, or a transmitting circuit, etc.

[0487] Fig.10 A structural diagram of a network device 1000 provided in an embodiment of the present application can be used to implement the functions of the network device in the above method. The network device 1000 includes one or more radio frequency units, such as a remote radio unit (RRU) 1010 and one or more baseband units (BBU) (also referred to as digital units, digital units, DU) 1020. The RRU 1010 can be referred to as a transceiver unit, a transceiver, a transceiver circuit, or a transceiver, etc., and it may include at least one antenna 1011 and a radio frequency unit 1012. The RRU 1010 part is mainly used for the transmission and reception of radio frequency signals and the conversion of radio frequency signals and baseband signals, for example, for sending the signaling message described in the above embodiment to the terminal device. The BBU 1020 part is mainly used for baseband processing, controlling the base station, etc. The RRU 1010 and the BBU 1020 can be physically arranged together or physically separated, that is, a distributed base station.

[0488] The BBU 1020 is the control center of the base station, which can also be called a processing unit, and is mainly used to complete baseband processing functions, such as channel coding, multiplexing, modulation, spread spectrum, etc. For example, the BBU (processing unit) 1020 can be used to control the network device to execute the operation flow of the network device in the above method embodiment.

[0489] In one example, the BBU 1020 may be composed of one or more single boards, and the multiple single boards may jointly support a wireless access network of a single access standard (such as an LTE system or a 5G system), or may respectively support wireless access networks of different access standards. The BBU 1020 also includes a memory 1021 and a processor 1022. The memory 1021 is used to store necessary instructions and data. The processor 1022 is used to control the network device to perform necessary actions, such as controlling the network device to execute the operation process of the network device in the above method embodiment. The memory 1021 and the processor 1022 can serve one or more single boards. In other words, a memory and a processor may be separately set on each single board. It is also possible that multiple single boards share the same memory and processor. In addition, necessary circuits may be set on each single board.

[0490] In a possible implementation, with the development of system-on-chip (SoC) technology, all or part of the functions of parts 1020 and 1010 can be implemented by SoC technology, for example, by a base station function chip, which integrates devices such as a processor, a memory, and an antenna interface, and the program of the base station-related functions is stored in the memory, and the processor executes the program to implement the relevant functions of the base station. Optionally, the base station function chip can also read the memory outside the chip to implement the relevant functions of the base station.

[0491] It should be understood that Fig.10 The structure of the network device in the example is only one possible form and should not constitute any limitation to the embodiments of the present application. The present application does not exclude the possibility of other forms of base station structures that may appear in the future.

[0492] According to the method provided in the embodiment of the present application, the embodiment of the present application also provides a communication system, which includes the aforementioned network device, a first terminal device and a second terminal device.

[0493] It should be understood that in the embodiments of the present application, the processor may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0494] It should also be understood that the memory in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

[0495] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0496] An embodiment of the present application also provides a computer-readable medium having a computer program stored thereon. When the computer program is executed by a computer, the steps executed by the network device in any of the above embodiments, or the steps executed by the first terminal device, or the steps executed by the second terminal device are implemented.

[0497] An embodiment of the present application also provides a computer program product, which, when executed by a computer, implements the steps executed by the network device in any of the above embodiments, or the steps executed by the first terminal device, or the steps executed by the second terminal device.

[0498] The embodiment of the present application also provides a system chip, which includes: a communication unit and a processing unit. The processing unit may be, for example, a processor. The communication unit may be, for example, an input / output interface, a pin, or a circuit. The processing unit may execute computer instructions to enable the chip in the communication device to execute the steps performed by the network device provided in the embodiment of the present application, or the steps performed by the first terminal device, or the steps performed by the second terminal device.

[0499] Optionally, the computer instructions are stored in a storage unit.

[0500] An embodiment of the present application also provides a communication system, including the network device, the first terminal device and the second terminal device in the aforementioned embodiment.

[0501] The various embodiments in this application may be used independently or in combination, which is not limited here.

[0502] In addition, various aspects or features of the present application can be implemented as methods, devices or products using standard programming and / or engineering techniques. The term "product" used in this application covers computer programs that can be accessed from any computer-readable device, carrier or medium. For example, computer-readable media may include, but are not limited to: magnetic storage devices (e.g., hard disks, floppy disks or tapes, etc.), optical disks (e.g., compact discs (CDs), digital versatile discs (DVDs), etc.), smart cards and flash memory devices (e.g., erasable programmable read-only memory (EPROM), cards, sticks or key drives, etc.). In addition, the various storage media described herein may represent one or more devices and / or other machine-readable media for storing information. The term "machine-readable medium" may include, but is not limited to, wireless channels and various other media capable of storing, containing and / or carrying instructions and / or data.

[0503] It should be noted that in the various embodiments provided in the present application, there is no time limit relationship between the various steps, and each step can be used as a scheme, or can be combined with one or more other steps to form a scheme, and the present application does not limit this.

[0504] The various embodiments in the present application may be used independently or in combination. For example, any one or more steps in the different embodiments may be combined to constitute an embodiment independently, which is not limited here.

[0505] It should be understood that in the embodiments shown above, the first and the second are only used to distinguish different objects and should not constitute any limitation to the present application.

[0506] It should also be understood that in the embodiments of the present application, the size of the serial numbers of the above processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0507] It should also be understood that "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previously associated objects are in an "or" relationship. "At least one" means one or more; "at least one of A and B" is similar to "A and / or B", describing the association relationship of associated objects, indicating that three relationships may exist. For example, at least one of A and B can represent three situations: A exists alone, A and B exist at the same time, and B exists alone.

[0508] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0509] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0510] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0511] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0512] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0513] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0514] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A communication method, applied to a second terminal device, characterized in that: include: In a case where it is determined that a first message from a network device is not successfully received or the first message is not successfully decoded, determining that an RRC state between the network device and a first terminal device is not aligned, wherein the first message is used to release or suspend a radio resource control RRC connection between the first terminal device and the network device; receiving first indication information, where the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device; Monitoring a paging message sent by a network device to the first terminal device; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

2. The method according to claim 1, characterized in that: Also includes: Send second indication information to the first terminal device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

3. The method according to claim 1 or 2, characterized in that: Also includes: Send third indication information to the first terminal device, where the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

4. The method according to claim 1, characterized in that The first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to instruct the first terminal device to enter an idle state; or The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

5. The method according to claim 4, characterized in that The first indication information comes from the network device.

6. The method according to claim 5, characterized in that The first indication information is carried in an RRC message or MAC CE sent by the network device to the second terminal device.

7. The method according to claim 1 or 2, characterized in that: The first indication information comes from the first terminal device.

8. The method according to any one of claims 1-2, 4-6, characterized in that: The first indication information includes an identifier of the first terminal device; The step of monitoring a paging message sent by the network device to the first terminal device includes: According to the identifier of the first terminal device, monitor the paging message sent by the network device to the first terminal device.

9. The method according to any one of claims 1-2, 4-6, characterized in that: Also includes: Receiving a paging message sent by the network device for the first terminal device; The paging message is sent to the first terminal device via the sidelink.

10. The method according to claim 9, characterized in that Before sending the paging message to the first terminal device through the side link, the method further includes: The sidelink is established or re-established.

11. A communication method, applied to a first terminal device, characterized in that: include: The second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded, wherein the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; Receiving second indication information from a second terminal device, and / or receiving a paging message forwarded by the second terminal device, wherein the second indication information is used to indicate that the first terminal device enters an idle state or a deactivated state, and the paging message is used by a network device to page the first terminal device; Entering an idle state or a deactivated state; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

12. The method according to claim 11, characterized in that Also includes: Receive third indication information from the second terminal device, where the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

13. The method according to claim 11 or 12, characterized in that: Before receiving the second indication information from the second terminal device, and / or receiving the paging message from the network device forwarded by the second terminal device, the method further includes: Establish or re-establish the sidelink.

14. The method according to claim 11 or 12, characterized in that: Upon receiving a paging message forwarded by the second terminal device from the network device, the entering the idle state or the deactivated state further includes: Initiate an RRC establishment / recovery process with the network device.

15. A communication method, characterized in that: include: Sending a first message to a second terminal device, where the second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded, and the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; Sending first indication information to a second terminal device, where the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

16. The method according to claim 15, characterized in that Also includes: Negative feedback information is received, where the negative feedback information is used to indicate that the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device.

17. The method according to claim 15 or 16, characterized in that The first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter an idle state; The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

18. The method according to claim 15 or 16, characterized in that The first indication information includes an identifier of the first terminal device.

19. The method according to claim 15 or 16, characterized in that Before sending the first indication information to the second terminal device, the method further includes: Send a paging message or an RRC establishment message to the second terminal device.

20. The method according to claim 15 or 16, characterized in that The first indication information is carried in an RRC message or a media access control element MAC CE.

21. A communication method, characterized in that: include: The second terminal device determines that no data or signaling of the first terminal device is received and / or sent during the first period of time; Determining that the first terminal device enters an idle state or a deactivated state; The second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded; the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; Monitoring a paging message sent by a network device to the first terminal device; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link; The step of determining that no data or signaling of the first terminal device is received or sent during the first time period includes: A timer is set to determine that no data or signaling of the first terminal device is received or sent within the first time period.

22. The method according to claim 21, characterized in that Also includes: Sending second indication information to the network device, wherein the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

23. The method according to claim 21 or 22, characterized in that Also includes: Receiving downlink data and / or signaling from the network device; Forward the downlink data and / or signaling to the first terminal device.

24. The method according to claim 21 or 22, characterized in that The second terminal device determines that no data or signaling of the first terminal device is received or sent during the first time period, including: Determine that the first timer has timed out, and determine that no data or signaling of the first terminal device has been received or sent within the first time period.

25. The method according to claim 24, characterized in that Also includes: Receive or send data or signaling from the first terminal device, and start or restart the first timer.

26. The method according to any one of claims 21-22 and 25, characterized in that: The first duration is configured by the network device.

27. The method according to any one of claims 21-22 and 25, characterized in that: Also includes: Send fourth indication information to the first terminal device, where the fourth indication information is used to indicate the first duration.

28. A communication method, characterized in that: include: The first terminal device determines that no data or signaling is received from the network device during the first time period, and / or no data or signaling is sent to the network device; Determining that the first terminal device enters an idle state or a deactivated state; The second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded; the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; The second terminal device monitors the paging message sent by the network device to the first terminal device; The first terminal device communicates with the network device via the second terminal device, and the first terminal device communicates with the second terminal device via a side link; Determining that no data or signaling is received from the network device during a first period of time, and / or that no data or signaling is sent to the network device, includes: A timer is set to determine that no data or signaling is received from the network device and / or no data or signaling is sent to the network device.

29. The method according to claim 28, characterized in that Also includes: Send second indication information to the second terminal device or the network device, where the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state.

30. The method according to claim 28 or 29, characterized in that Also includes: Receiving downlink data and / or signaling from the network device forwarded by the second terminal device; And / or, initiating an RRC establishment / recovery process with the network device.

31. The method according to claim 28 or 29, characterized in that The first terminal device determines that the first terminal device has not received data or signaling from a network device for a first period of time, and / or has not sent data or signaling to the network device, including: When it is determined that the second timer has timed out, it is determined that no data or signaling has been received from the network device during the first time period, and / or no data or signaling has been sent to the network device.

32. The method according to claim 31, characterized in that Also includes: Receive data or signaling from the network device, and / or send data or signaling to the network device, and start or restart the second timer.

33. The method according to any one of claims 28-29 and 32, characterized in that: Also includes: Receive fourth indication information from the second terminal device, where the fourth indication information is used to indicate the first duration.

34. A communication device, characterized in that: include: a processing unit, configured to determine that a first message from a network device is not successfully received or that the first message is not successfully decoded; Determining that an RRC state between the network device and the first terminal device is not aligned, wherein the first message is used to release or suspend a radio resource control RRC connection between the first terminal device and the network device; A transceiver unit, configured to receive first indication information, wherein the first indication information is used to instruct the second terminal device to monitor a paging message for the first terminal device; A processing unit, configured to monitor a paging message sent by a network device to the first terminal device; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

35. The device according to claim 34, characterized in that The transceiver unit is further used to send second indication information to the first terminal device, where the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

36. The device according to claim 34 or 35, characterized in that The transceiver unit is also used to send third indication information to the first terminal device, and the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

37. The device according to claim 34, characterized in that The first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to instruct the first terminal device to enter an idle state; or The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

38. The device according to claim 37, characterized in that The first indication information comes from the network device.

39. The device according to claim 38, characterized in that The first indication information is carried in an RRC message or MAC CE sent by the network device to the second terminal device.

40. The device according to claim 34 or 35, characterized in that The first indication information comes from the first terminal device.

41. The device according to any one of claims 34-35, 37-39, characterized in that The first indication information includes an identifier of the first terminal device; The processing unit is specifically configured to monitor, according to an identifier of the first terminal device, a paging message sent by the network device to the first terminal device.

42. The device according to any one of claims 34-35, 37-39, characterized in that The transceiver unit is also used for: Receiving a paging message sent by the network device for the first terminal device; The paging message is sent to the first terminal device via the sidelink.

43. The device according to claim 42, characterized in that The processing unit is further configured to establish or reestablish the sidelink.

44. A communication device, characterized in that: include: The second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded, wherein the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; a transceiver unit, configured to receive second indication information from a second terminal device, and / or receive a paging message forwarded by the second terminal device, wherein the second indication information is used to indicate that the first terminal device enters an idle state or a deactivated state, and the paging message is used by a network device to page the first terminal device; A processing unit, configured to enter an idle state or a deactivated state; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

45. The device according to claim 44, characterized in that The transceiver unit is also used to receive third indication information from the second terminal device, and the third indication information is used to instruct the first terminal device to release the side link configuration between the first terminal device and the second terminal device, and / or the air interface link configuration between the first terminal device and the network device.

46. ​​The device according to claim 44 or 45, characterized in that The processing unit is further configured to establish or re-establish the sidelink.

47. The device according to claim 44 or 45, characterized in that The processing unit is specifically configured to initiate an RRC establishment / recovery process with the network device.

48. A communication device, characterized in that: include: a transceiver unit, configured to send a first message to a second terminal device, wherein the second terminal device determines that the RRC states between the network device and the first terminal device are not aligned when determining that the first message from the network device is not successfully received or the first message is not successfully decoded, and the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; The transceiver unit is further used to send first indication information to the second terminal device, where the first indication information is used to instruct the second terminal device to monitor the paging message for the first terminal device; The first terminal device communicates with the network device through the second terminal device, and the first terminal device and the second terminal device communicate with each other through a side link.

49. The device according to claim 48, characterized in that The transceiver unit is further used to receive negative feedback information, where the negative feedback information is used to indicate that the first message is not successfully sent to the second terminal device, or the first message is not successfully decoded by the second terminal device.

50. The device according to claim 48 or 49, characterized in that The first message is used to release the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter an idle state; or The first message is used to suspend the RRC connection between the first terminal device and the network device, and the first message is used to configure the first terminal device to enter a deactivated state.

51. The device according to claim 48 or 49, characterized in that The first indication information includes an identifier of the first terminal device.

52. The device according to claim 48 or 49, characterized in that The transceiver unit is also used to send a paging message or an RRC establishment message to the second terminal device.

53. The device according to claim 48 or 49, characterized in that The first indication information is carried in an RRC message or a media access control element MAC CE.

54. A communication device, characterized in that: include: A processing unit, configured to determine that no data or signaling of the first terminal device is received and / or sent during a first time period; The processing unit is further used to determine that the first terminal device enters an idle state or a deactivated state; The processing unit is further configured to determine that the RRC states between the network device and the first terminal device are not aligned when it is determined that the first message from the network device is not successfully received or the first message is not successfully decoded; the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; The processing unit is further configured to monitor a paging message sent by the network device to the first terminal device; The first terminal device communicates with the network device via the second terminal device, and the first terminal device communicates with the second terminal device via a side link; The processing unit is specifically used to: set a timer to determine that no data or signaling of the first terminal device is received or sent within the first time period.

55. The device according to claim 54, characterized in that Also includes: A transceiver unit is used to send second indication information to the network device, and the second indication information is used to instruct the first terminal device to enter an idle state or a deactivated state.

56. The device according to claim 54 or 55, characterized in that Also includes: A transceiver unit is used to receive downlink data and / or signaling from the network device and forward the downlink data and / or signaling to the first terminal device.

57. The device according to claim 54 or 55, characterized in that The processing unit is specifically used for: Determine that the first timer has timed out, and determine that no data or signaling of the first terminal device has been received or sent within the first time period.

58. The device according to claim 57, characterized in that Also includes: A transceiver unit is used to receive or send data or signaling of the first terminal device, and start or restart the first timer.

59. The device according to any one of claims 54-55 and 58, characterized in that The first duration is configured by the network device.

60. The device according to any one of claims 54-55 and 58, characterized in that Also includes: A transceiver unit is used to send fourth indication information to the first terminal device, and the fourth indication information is used to indicate the first duration.

61. A communication device, characterized in that: include: a processing unit, configured to determine that no data or signaling is received from the network device during a first time period, and / or that no data or signaling is sent to the network device; The processing unit is specifically used to: set a timer to determine that no data or signaling is received from the network device, and / or no data or signaling is sent to the network device; the processing unit is also used to determine that the first terminal device enters an idle state or a deactivated state; The second terminal device is used to determine that the RRC states between the network device and the first terminal device are not aligned when it is determined that the first message from the network device is not successfully received or the first message is not successfully decoded; the first message is used to release or suspend the radio resource control RRC connection between the first terminal device and the network device; The second terminal device is used to monitor the paging message sent by the network device to the first terminal device; The first terminal device communicates with the network device via the second terminal device, and the first terminal device communicates with the second terminal device via a side link.

62. The device according to claim 61, characterized in that Also includes: A transceiver unit is used to send second indication information to the second terminal device or the network device, and the second indication information is used to indicate that the first terminal device is in an idle state or a deactivated state.

63. The device according to claim 61 or 62, characterized in that Also includes: a transceiver unit, configured to receive downlink data and / or signaling from the network device forwarded by the second terminal device; The processing unit is further configured to initiate an RRC establishment / recovery process with the network device.

64. The device according to claim 61 or 62, characterized in that The processing unit is specifically used for: When it is determined that the second timer has timed out, it is determined that no data or signaling has been received from the network device during the first time period, and / or no data or signaling has been sent to the network device.

65. The device according to claim 64, characterized in that Also includes: A transceiver unit, configured to receive data or signaling from a network device, and / or send data or signaling to the network device; The processing unit is further configured to start or restart the second timer.

66. The device according to any one of claims 61-62 and 65, characterized in that Also includes: A transceiver unit is used to receive fourth indication information from the second terminal device, and the fourth indication information is used to indicate the first duration.

67. A communication device, characterized in that: include: A processor and a transceiver, wherein the processor is used to call and run a computer program from a memory to execute the method according to any one of claims 1 to 33.

68. The communication device according to claim 67, characterized in that Also includes: The memory.

69. A computer-readable storage medium, characterized in that The storage medium stores a computer program or instruction, and when the computer program or instruction is executed by the communication device, the method as claimed in any one of claims 1 to 33 is implemented.

70. A communication chip, characterized in that: The chip comprises: A processor and a communication interface, wherein the processor is used to call and run instructions from the communication interface, and when the processor executes the instructions, the method as described in any one of claims 1-33 is implemented.

71. A communication system, characterized in that: include: An apparatus for performing the method according to any one of claims 1 to 10, an apparatus for performing the method according to any one of claims 11 to 14, and an apparatus for performing the method according to any one of claims 15 to 20; or An apparatus for executing the method according to any one of claims 21 to 27, an apparatus for executing the method according to any one of claims 28 to 33.

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