CN111757377B

CN111757377B - Method and terminal for monitoring direct link

Info

Publication number: CN111757377B
Application number: CN201910365326.7A
Authority: CN
Inventors: 王达; 谌丽
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2019-03-28
Filing date: 2019-04-30
Publication date: 2022-05-31
Anticipated expiration: 2039-04-30
Also published as: CN111757377A

Abstract

The embodiment of the invention provides a method and a terminal for monitoring a direct link, wherein the method comprises the following steps: a first terminal monitors the quality of a direct link to obtain the state of the direct link, wherein the direct link is the direct link between the first terminal and a second terminal; when the direct link state is a first state, the first terminal reports the direct link state to an access layer of the first terminal; or, when the direct link state is the second state, the first terminal reports the direct link state to an access layer of the first terminal, or indicates the direct link state by not reporting the direct link state to the access layer. The embodiment of the invention can realize the link monitoring of the direct link supporting the unicast or multicast service so as to improve the monitoring effect of the direct link and further improve the transmission performance of the unicast or multicast service.

Description

Method and terminal for monitoring direct link

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and a terminal for monitoring a direct link.

Background

In a Long Term Evolution (LTE) system, a direct link (sidelink) supports only a broadcast service, and a direct link for a subsequent communication system may support other services in addition to the broadcast service, for example: the direct link of the New Radio (NR) system may support unicast and multicast services in addition to broadcast services. Since Radio Link Monitoring (RLM) cannot be applied to a direct Link supporting unicast or multicast services, Link Monitoring of a direct Link supporting unicast or multicast services cannot be implemented at present.

Disclosure of Invention

The embodiment of the invention provides a method and a terminal for monitoring a direct link, which aim to solve the problem that the link monitoring of the direct link supporting unicast or multicast service cannot be realized.

The embodiment of the invention provides a method for monitoring a direct link, which comprises the following steps:

a first terminal monitors the quality of a direct link to obtain the state of the direct link, wherein the direct link is between the first terminal and a second terminal;

when the direct link state is a first state, the first terminal reports the direct link state to an access layer of the first terminal; alternatively, the first and second electrodes may be,

and under the condition that the direct link state is the second state, the first terminal reports the direct link state to an access layer of the first terminal, or indicates the direct link state by not reporting the direct link state to the access layer.

Optionally, the first state includes a synchronization state or an out-of-synchronization state;

the second state includes an invalid (None) state, where the pass-through link state is the None state if the first terminal does not receive a signal sent by the second terminal.

Optionally, the method further includes:

and the first terminal reports Radio Link Failure (RLF) to a high layer of the first terminal according to the state of the direct Link received by the access layer.

Optionally, when the first terminal is a receiving end on the direct link, the first terminal performs RLF reporting to a high layer of the first terminal according to the direct link state received by the access layer, where the RLF reporting includes at least one of the following:

if the access stratum continuously receives N1 out-of-sync states, starting a first timer, and reporting to a high layer of the first terminal by using an RLF (radio link failure) under the condition that the first timer is overtime, wherein the condition that the first timer stops comprises that the access stratum continuously receives N11 in-sync states;

if the access stratum continuously receives N2 None states, starting a second timer, and performing RLF reporting to a higher layer of the first terminal under the condition that the second timer is overtime, wherein a condition that the second timer stops includes that the access stratum continuously receives N22 synchronization states;

if the access stratum continuously receives N3 states, starting a third timer, and reporting to a high layer of the first terminal by using an RLF (radio link failure) under the condition that the third timer is overtime, wherein the condition that the third timer stops comprises that the access stratum continuously receives N33 synchronous states, and N3 is the sum of the number of out-of-step states and None states;

wherein, N1, N2, N3, N11, N22 and N33 are positive integers, N33 is more than or equal to N22, and N22 is more than or equal to N11.

Optionally, at least one of the duration of the first timer, the duration of the second timer, the duration of the third timer, N1, N2, N3, N11, N22, and N33 is: pre-configured, protocol pre-defined or network side configured or configured by other terminals, wherein the other terminals comprise:

a sending terminal, a control terminal, a group head terminal, a cluster head terminal or a management terminal.

Optionally, when the first terminal is a sending end on the direct link, the first terminal performs RLF reporting to a higher layer of the first terminal according to the direct link state received by the access layer, where the RLF reporting includes:

if the access stratum continuously receives N4 out-of-sync states, starting a fourth timer, and reporting RLF to a higher layer of the first terminal when the fourth timer is overtime, where a condition that the fourth timer stops includes that the access stratum continuously receives N44 in-sync states, where N4 and N44 are positive integers.

Optionally, at least one of the duration of the fourth timer, N4, and N44 is: pre-configured, protocol pre-defined or network side configured or configured by other terminals, wherein the other terminals comprise:

the system comprises a receiving terminal, a control terminal, a group head terminal, a cluster head terminal or a management terminal.

Optionally, if a direct link Physical Control Channel (PSCCH) signal sent by at least one second terminal is received, the signal is in a synchronous state; if the PSCCH signal sent by any second terminal is not received, the state is in an out-of-step state or in a None state; alternatively, the first and second electrodes may be,

if receiving ACK or NACK carried on PSFCH sent by at least one second terminal, the state is synchronous; if the signal carried on the PSFCH sent by any second terminal is not received, the state is in an out-of-step state; alternatively, the first and second electrodes may be,

if receiving ACK carried on PSFCH sent by at least one second terminal or receiving NACK carried on PSFCH sent by less than M second terminals, the state is synchronous; and if NACK carried on the PSFCH sent by more than or equal to M second terminals is received, the state is in an out-of-step state, and M is a positive integer more than or equal to 1.

Optionally, the reporting, by the first terminal, the direct link status to the access layer of the first terminal includes:

and the first terminal periodically reports the direct link state to an access layer of the first terminal.

Optionally, the monitoring, by the first terminal, the quality of the direct link includes:

when the first terminal is a receiving terminal on the direct Link, the first terminal monitors a PSCCH Signal or a Radio Link Monitoring Reference Signal (RLM-RS) sent by the second terminal on the direct Link; or

And when the first terminal is a sending terminal on the direct link, the first terminal monitors a direct link feedback channel (PSFCH) signal or an RLM-RS sent by the second terminal on the direct link.

Optionally, the RLM-RS includes at least one of:

sequence-based Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK), Demodulation Reference Signal (DMRS), Channel State Information Reference Signal (CSI-RS), and Synchronization Signal Block (SSB).

An embodiment of the present invention further provides a terminal, where the terminal is a first terminal, and the terminal includes:

the monitoring module is used for monitoring the quality of a direct link to obtain the state of the direct link, wherein the direct link is the direct link between the first terminal and the second terminal;

the second state includes a None state, where the direct link state is the None state when the first terminal does not receive a signal sent by the second terminal.

Optionally, the first terminal further includes:

and a reporting module, configured to perform RLF reporting on radio link failure to a higher layer of the terminal according to the direct link state received by the access layer.

Optionally, the reporting module includes at least one of the following:

a first reporting unit, configured to start a first timer if the access stratum continuously receives N1 out-of-sync states, and perform RLF reporting to a higher layer of the first terminal when the first timer expires, where a condition that the first timer stops includes that the access stratum continuously receives N11 out-of-sync states;

a second reporting unit, configured to start a second timer if the access stratum continuously receives N2 None states, and perform RLF reporting to a higher layer of the first terminal if the second timer is overtime, where a condition that the second timer stops includes that the access stratum continuously receives N22 synchronization states;

a third reporting unit, configured to start a third timer if the access stratum continuously receives N3 states, and perform RLF reporting to a higher layer of the first terminal if the third timer is overtime, where a condition that the third timer stops includes that the access stratum continuously receives N33 synchronous states, and N3 is a sum of numbers of out-of-synchronization states and None states;

Optionally, the reporting module is configured to start a fourth timer if the access stratum continuously receives N4 out-of-sync states, and report the RLF to a higher layer of the first terminal when the fourth timer expires, where a condition that the fourth timer stops includes that the access stratum continuously receives N44 out-of-sync states, where N4 and N44 are positive integers.

An embodiment of the present invention further provides a terminal, where the terminal is a first terminal, and the terminal includes: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

the transceiver is configured to monitor the quality of a direct link, and obtain a state of the direct link, where the direct link is a direct link between the first terminal and the second terminal;

wherein, when the direct link status is a first status, the transceiver or the processor is configured to report the direct link status to an access layer of the first terminal; alternatively, the first and second electrodes may be,

and when the direct link state is the second state, the transceiver or the processor is configured to report the direct link state to an access layer of the first terminal, or indicate the direct link state by not reporting the direct link state to the access layer.

the second state includes an invalid None state, where the direct link state is the None state when the first terminal does not receive a signal sent by the second terminal.

Optionally, the transceiver or the processor is further configured to:

and according to the direct link state received by the access layer, reporting Radio Link Failure (RLF) to a high layer of the first terminal.

Optionally, when the first terminal is a receiving end on the direct link, the reporting, to the higher layer of the first terminal, of the radio link failure RLF according to the direct link state received by the access stratum includes at least one of:

if the access stratum continuously receives N2 None states, starting a second timer, and performing RLF (radio link failure) reporting to a high layer of the first terminal under the condition that the second timer is overtime, wherein the condition that the second timer stops comprises that the access stratum continuously receives N22 synchronous states;

Optionally, when the first terminal is a transmitting end on the direct link, the reporting, to the high layer of the first terminal, of the radio link failure RLF according to the direct link state received by the access layer includes:

The present invention also provides a computer-readable storage medium, on which a computer program is stored, where the computer program, when executed by a processor, implements the steps in the direct link monitoring method provided in the embodiments of the present invention.

In the embodiment of the invention, a first terminal monitors the quality of a direct link to obtain the state of the direct link, wherein the direct link is between the first terminal and a second terminal; when the direct link state is a first state, the first terminal reports the direct link state to an access layer of the first terminal; and under the condition that the direct link state is the second state, the first terminal reports the direct link state to an access layer of the first terminal, or indicates the direct link state by not reporting the direct link state to the access layer. Therefore, the link monitoring of the direct link supporting the unicast or multicast service can be realized, the monitoring effect of the direct link is improved, and the transmission performance of the unicast or multicast service can be further improved.

Drawings

FIG. 1 is a schematic diagram of a network architecture to which embodiments of the present invention are applicable;

fig. 2 is a flowchart of a direct link monitoring method according to an embodiment of the present invention;

fig. 3 is a schematic diagram of RLF reporting according to an embodiment of the present invention;

fig. 4 is a schematic diagram of another RLF reporting according to an embodiment of the present invention;

fig. 5 is a schematic diagram of another RLF reporting according to an embodiment of the present invention;

fig. 6 is a schematic diagram of another RLF report according to an embodiment of the present invention;

fig. 7 is a structural diagram of a terminal according to an embodiment of the present invention;

fig. 8 is a block diagram of another terminal provided in an embodiment of the present invention;

fig. 9 is a block diagram of another terminal provided in an embodiment of the present invention;

fig. 10 is a block diagram of another terminal according to an embodiment of the present invention.

Detailed Description

In order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

Referring to fig. 1, fig. 1 is a schematic diagram of a network structure to which the embodiment of the present invention is applicable, and as shown in fig. 1, the network structure includes a plurality of terminals 11 and a network side device 12, where the terminal 11 may be a User Equipment (UE) or other terminal devices, for example: the present invention relates to a Mobile terminal, and more particularly to a Mobile terminal, a Tablet Personal Computer (Tablet Personal Computer), a Laptop Computer (Laptop Computer), a Personal Digital Assistant (PDA), a Mobile Internet Device (MID), a Wearable Device (Wearable Device), a robot, a vehicle, and other terminal-side devices. The direct link through which the terminals 11 can directly communicate is called a Sidelink (which translates to a direct communication link or bypass, also called a direct communication interface or a direct link interface), that is, the terminals can directly communicate with each other through the Sidelink. The terminals of the direct communication can be all on-line or all off-line, or part of the devices are on-line and part of the devices are off-line. The network side device 12 may be a base station, for example: macro station, LTE eNB, 5G NR NB, etc.; the network side device may also be a small station, such as a Low Power Node (LPN), pico, femto, or the network side device may be an Access Point (AP); the Network-side Device may also be a Network node formed by a Central Unit (CU) and a plurality of Transmission Reception Points (TRPs) managed and controlled by the CU, and a cellular communication link between the Network-side Device and a terminal-side Device in direct communication is referred to as a Device-to-Network (D2N) link, or a Uu interface. It should be noted that, in the embodiment of the present invention, the specific type of the network-side device is not limited.

Referring to fig. 2, fig. 2 is a flowchart of a method for monitoring a direct link according to an embodiment of the present invention, and as shown in fig. 2, the method includes the following steps:

201. a first terminal monitors the quality of a direct link to obtain the state of the direct link, wherein the direct link is the direct link between the first terminal and a second terminal;

when the direct link state is a first state, the first terminal reports the direct link state to an access layer of the first terminal; alternatively, the first and second liquid crystal display panels may be,

The above-mentioned direct link between the first terminal and the second terminal may also be understood as a link supporting unicast or multicast service between the first terminal and the second terminal.

In addition, the first terminal may monitor an RLM-RS sent by the second terminal, or may monitor a PSCCH signal sent by the second terminal by the first terminal, or the first terminal monitors a PSCCH signal sent by the second terminal, where it is to be explained that the PSCCH signal may be a HARQ-ACK feedback signal carried on the PSCCH, and the PSCCH signal may be a Scheduling Assignment (SA) or a direct link control information (SCI) signal carried on the PSCCH, where the HARQ-ACK feedback signal includes three types, and if the information is correctly received, an ACK is fed back, and if the information is received incorrectly, a NACK is fed back, and if none of the information is received, no feedback is given back, that is, Discontinuous Transmission (DTX). The direct link state may be a direct link state obtained according to a monitoring result of the first terminal monitoring the quality of the direct link. Further, the above-mentioned direct link status may be a direct link monitoring quality result.

The first state and the second state may be predefined through link states and two different through link states.

By the steps, the direct link state is reported to an Access Stratum (AS) under the condition that the direct link state is the first state; and when the through link state is the second state, the through link state may be reported to the access layer, or the through link state may be indicated by not reporting the through link state to the access layer, that is, when the access layer does not receive the through link state, the access layer confirms that the through link state monitored by the first terminal is the second state, thereby reducing reporting and saving power consumption.

In the embodiment of the invention, the link monitoring of the direct link supporting the unicast or multicast service can be realized through the steps, so that the monitoring effect of the direct link is improved, and the transmission performance of the unicast or multicast service can be further improved.

As an alternative embodiment, the first state comprises an In-sync state (In-sync) or an Out-of-sync state (Out-of-sync);

the second state includes an invalid (None) state, where the direct link state is the None state when the first terminal does not receive a signal transmitted by the second terminal.

The synchronous state and the out-of-step state may be determined according to a preset threshold, for example: if the link quality of any RLM-RS is monitored to be higher than a preset first threshold (for example, the threshold Qin), the RLM-RS is in a synchronous state, and if the link quality of all RLM-RS is monitored to be lower than a preset second threshold (for example, the threshold Qout), the RLM-RS is in an out-of-synchronization state, where values of the preset first threshold and the preset second threshold may be different or the same, and are not limited.

For another example, if the PSCCH signal transmitted by at least one second terminal is received, the PSCCH signal is in a synchronous state, and if the PSCCH signal transmitted by any second terminal is not successfully received, the PSCCH signal is in an out-of-synchronization state or an invalid (None) state.

For another example, if the ACK or NACK carried on the PSFCH sent by at least one second terminal is received, the state is in the synchronized state, and if the signal carried on the PSFCH sent by any second terminal is not received, the state is in the out-of-synchronization state. In addition, if the second terminal does not transmit any PSFCH signal, it is in an inactive (None) state.

Another example is: if receiving ACK carried on PSFCH sent by at least one second terminal or receiving NACK carried on PSFCH sent by less than M second terminals, the state is synchronous; and if NACK carried on the PSFCH sent by more than or equal to M second terminals is received, the state is in an out-of-step state, and M is a positive integer more than or equal to 1.

Wherein, the M is configured or pre-configured by the network or specified by the protocol.

If the signal carried on the PSFCH and sent by any second terminal is not received, the second terminal does not feed back the PSFCH signal, that is, DTX, if the second terminal does not receive the information sent by the first terminal, so that the first terminal does not receive the PSFCH signal sent by the second terminal; alternatively, the second terminal may receive the information transmitted by the first terminal and transmit the PSFCH feedback signal (ACK is fed back if the information is correctly received and NACK is fed back if the information is incorrectly received), but the first terminal may not receive the PSFCH signal transmitted by the second terminal.

The received PSCCH signal or PSFCH signal may be considered as a successfully received PSCCH signal or PSFCH signal, or may be considered as a received PSCCH signal or PSFCH signal that identifies the PSCCH signal or PSFCH signal transmitted by the second terminal.

The above explanation for the in-synchronization state and the out-of-synchronization state may be a direct link state obtained by monitoring, detecting, receiving, or measuring one or more signals in one cycle, or may be a direct link state obtained by non-periodically monitoring, detecting, receiving, or measuring one or more signals, which is not limited in the present invention.

The signal transmitted by the second terminal may be a PSCCH signal or a reference signal or a PSFCH signal transmitted by the second terminal, for example: in a case where the first terminal is a receiving end of the through link and the second terminal is a transmitting end of the through link, the signal is a PSCCH signal or a reference signal, such as an RLM-RS, and in a case where the first terminal is the transmitting end of the through link and the second terminal is the receiving end of the through link, the signal is a reference signal or a PSFCH signal.

In addition, the PSCCH signal or the reference signal that is not received by the first terminal and transmitted by the second terminal may be a PSCCH signal or a reference signal that is not transmitted by the second terminal, or may be a PSCCH signal or a reference signal that is transmitted by the second terminal, but the PSCCH signal or the reference signal that is transmitted by the second terminal is not received by the first terminal. For example: when the first terminal is a receiving end of the direct link and the second terminal is a transmitting end of the direct link, the non-reception includes two meanings, the first meaning is that the second terminal does not transmit a PSCCH signal or a reference signal, the second meaning is that the transmitting end transmits a PSCCH signal or a reference signal, but the first meaning is not received; when the first terminal is a transmitting end of the through link and the second terminal is a receiving end of the through link, the non-reception may indicate that the second terminal does not transmit a signal.

In this embodiment, the quality state of the through link can be accurately represented by the synchronization state, the out-of-synchronization state, and the None state, so as to improve the monitoring effect.

As an optional implementation, the method further includes:

and the first terminal reports RLF to the high layer of the first terminal according to the direct link state received by the access layer.

The higher layer may be a higher layer of the Access Stratum (or may be a higher layer of the Access Stratum), such as a Non-Access Stratum (NAS) or an application layer (application layer). In addition, the RLF report may be an RLF declaration (RLF declaration).

In this embodiment, RLF reporting to a higher layer can be achieved, so that reestablishment of the direct link or stop of information transmission can be performed in time, and transmission performance of the direct link can be improved or channel resources of the direct link can be saved.

In this embodiment, when the first state includes an in-synchronization state or an out-of-synchronization state, and the second state includes a None state, the following embodiments may be included:

in a first embodiment, when the first terminal is a receiving end on the direct link, the first terminal performs RLF reporting to a higher layer of the first terminal according to a direct link state received by the access layer, where the RLF reporting includes at least one of:

The receiving end may be a terminal that receives data in the direct link.

In addition, the durations of the first timer, the second timer and the third timer may be preconfigured, predefined by a protocol, or configured by the network side, or configured by other terminals to the receiving terminal, where the other terminals may be a sending terminal, a control terminal, a group head or cluster head terminal, a management terminal in a terminal group, and the like. And the time lengths of the first timer, the second timer and the third timer can be the same or different. In addition, in the embodiment of the present invention, the timers may also be referred to as timers, and each timer may be an RLF timer (RLF timer).

In addition, at least one of the time length of the first timer, the time length of the second timer, the time length of the third timer, N1, N2, N3, N11, N22, and N33 is: pre-configured, protocol pre-defined, or network side configured, or configured by other terminals, including but not limited to the following:

For example: in a case where the first terminal is a receiving terminal of the direct link and the second terminal is a transmitting terminal of the direct link, the parameter may be configured by the second terminal, a control terminal, a group head terminal, a cluster head terminal, a management terminal in a terminal group, or the like.

And the continuous reception of N3 states by the access layer may be the reception of N3 states, which are all out-of-sync states and None states. For example: taking N3 above as an example of 3, the third timer is started when the out-of-step state, and the None state are continuously received, or the third timer is started when the None state, and the None state are continuously received, or the out-of-step state, and the out-of-step state are continuously received. That is, if the number of continuously received out-of-synchronization states and/or None states reaches N3, the third timer is started.

In this embodiment, the receiving end may accurately and timely perform RLF reporting for a plurality of situations, and since N33 is greater than or equal to N22 and N22 is greater than or equal to N11, the sending end may not send a signal in the None state, and thus the timer may be stopped as soon as the None state changes to the synchronous state, so as to avoid an erroneous reporting.

In a second embodiment, when the first terminal is a transmitting end on the direct link, the performing, by the first terminal, RLF reporting to a higher layer of the first terminal according to the direct link state received by the access layer includes:

Wherein at least one of the duration of the fourth timer, N4, and N44 is: pre-configured, protocol pre-defined, or network side configured, or configured by other terminals, including but not limited to the following:

For example: in a case where the first terminal is a transmitting terminal of the direct link and the second terminal is a receiving terminal of the direct link, the fourth timer, N4 and N44 are configured in advance, defined by a protocol, or configured on a network side, or configured by another terminal to the transmitting terminal, where the another terminal may be a receiving terminal, a control terminal, a group head or cluster head terminal, a management terminal in a terminal group, or the like.

In the embodiment, the transmitting end can accurately and timely report the RLF.

As an optional implementation manner, the reporting, by the first terminal, the direct link status to the access layer of the first terminal includes:

The reporting period may be configured, preconfigured, or default in a protocol, or configured by another terminal to the receiving terminal or the sending terminal, for example, 10ms or 5ms, and the like, where the another terminal may be the sending terminal, the receiving terminal, the control terminal, the group head or cluster head terminal, the management terminal in the terminal group, and the like.

In this embodiment, the through link state may be reported to the access layer periodically, and may be reported in one period, and in addition, the through link state in one period may be a through link state obtained according to one or more signals monitored in the period.

As an optional implementation manner, the monitoring, by the first terminal, the quality of the direct link includes:

under the condition that the first terminal is a receiving end on the direct link, the first terminal monitors a PSCCH signal or RLM-RS sent by the second terminal on the direct link; or

And under the condition that the first terminal is a transmitting end on the direct link, the first terminal monitors a PSFCH signal or RLM-RS sent by the second terminal on the direct link.

Wherein, the RLM-RS may include at least one of:

HARQ-ACK、DMRS、CSI-RS、SSB。

wherein, the SSB may be transmitted periodically or aperiodically.

In addition, the RLM-RS transmitted by the transmitting end may be transmitted along with data of the direct link, for example: and the DMRS, CSI-RS or SSB transmitted by the transmitting end is transmitted along with the data of the direct link. The RLM-RS transmitted by the receiving end may be transmitted along with the PSFCH of the direct link, for example: the DMRS, CSI-RS, or SSB transmitted by the receiving end is transmitted along with the PSFCH of the direct link, and the HARQ-ACK may be transmitted on the PSFCH.

And the PSFCH signal may include:

sequence-based HARQ-ACK; or

DMRS based HARQ-ACK; or

Channel State Information (CSI) report based on DMRS; or

DMRS-based HARQ-ACK and CSI-RS; or

A CSI report based on DMRS and a CSI-RS.

In the embodiment of the present invention, the implementation manner provided above can be implemented as follows: the first terminal reports the state of the direct link according to the monitoring result of the direct link between the first terminal and the second terminal, wherein the state of the direct link comprises any one of In-sync (In-sync), out-of-sync (out-of-sync) and None state (or nothing is reported).

The following examples respectively take the first terminal as the receiving UE and the sending UE:

method for monitoring a direct link for a receiving UE:

the period of reporting link quality by the UE may be set, and in this period, the UE physical layer needs to report the access layer, and the link quality result (i.e. the above-mentioned direct link state) is reported.

The reporting period may be configured, preconfigured, or default in protocol, or configured by other UEs to the receiving UE or the sending UE, for example, 10ms or 5ms, where the other UEs may be the sending UE, the receiving UE, the control UE, the group head or cluster head UE, the management UE in the UE group, and the like.

The reported link quality results include In-sync, Out-of-sync and None states, that is, link quality is reported, except for In-sync and Out-of-sync, None is reported, or nothing is reported;

none status may be reported, indicating None status, and In-sync and Out-of-sync reporting may be similar to In-sync and Out-of-sync reporting at the NR Uu port, for example: according to the threshold judgment of Qin and Qout, if the link quality of any RLM-RS In the period is higher than Qin, reporting In-sync, and if the link quality of all RLM-RSs In the period is lower than Qout, reporting Out-of-sync;

or, if the PSCCH signal transmitted by at least one second terminal is received, the PSCCH signal is in a synchronous state, and if the PSCCH signal transmitted by any second terminal is not received, the PSCCH signal is in an out-of-synchronization state or an invalid (None) state.

The received PSCCH signal or PSFCH signal may be considered as a successful PSCCH signal or PSFCH signal, or may be considered as a received PSCCH signal or PSFCH signal that identifies that the PSCCH signal or PSFCH signal is transmitted by the second terminal.

The above explanation for the in-sync state and the out-of-sync state may be a through link state obtained by monitoring or receiving one or more signals in one cycle, or may be a through link state obtained by non-periodically monitoring or receiving one or more signals, which is not limited in the present invention.

Reporting None status (or nothing), there are two cases: first, the transmitting end does not transmit PSCCH signal or RLM-RS in the period, i.e. the transmitting end does not transmit signal in the period; secondly, the sending end sends a PSCCH signal or RLM-RS in a period, namely the sending end sends a signal in the period, but the receiving end does not receive any PSCCH signal or RLM-RS in the period due to poor link;

in addition, the RLM-RS may refer to a DMRS, a CSI-RS, or an SSB on a direct link (SL) port, which are transmitted along with data of the SL port, and thus, the RLM-RS is not transmitted if the transmitting UE does not transmit data. Wherein, the SSB may be transmitted periodically or aperiodically.

In addition, it should be noted that, since the above-mentioned embodiments of the present invention may be applied to a unicast service or a multicast service in a direct link system of NR, taking the unicast service as an example, the PSCCH signal or RLM-RS of the direct link may be aperiodic, so there is a case where there is no PSCCH signal or RLM-RS of the direct link in the period.

Therefore, there are 3 states of reported link quality, In-Sync, Out-of-Sync and None (or nothing is reported), and the specific RLF process refers to the transition between In-Sync & Out-of-Sync states as shown In fig. 3, the transition between In-Sync & None states as shown In fig. 4, and the transition between In-Sync & Out-of-Sync & None states as shown In fig. 5; here, N3 consecutive out-of-sync states or None states in fig. 5 may represent N3 consecutive received states described in the above embodiment.

It should be noted that, for the above procedure, it can be ensured that N33 is greater than or equal to N22, and N22 is greater than or equal to N11, because there is a possibility that None sends no signal to the UE, therefore, when the RLF timer is started In multiple None states continuously received, the RLF timer can be stopped as soon as possible after the In-sync is received, and false alarms are avoided.

Other parameters, such as N1, N2, N3, T1, T2, T3, may be equal or different. In addition, for the parameters in the above procedure, N1, N2, N3, T1, T2, T3, N11, N22, and N33 may be configured to the receiving UE through the network, or through pre-configuration, or through other UEs, where the other terminals may be the sending UE, the controlling UE, the group head or cluster head UE, the managing UE in the UE group, and the like.

The method for monitoring the direct link for the sending UE comprises the following steps:

the sending UE can receive a PSFCH direct link feedback channel or RLM-RS sent by the receiving UE to perform link monitoring;

the PSFCH can be designed as follows:

sequence-based HARQ-ACK;

DMRS-based HARQ-ACK or CSI report, i.e. HARQ-ACK/CSI report + DMRS, or it is also possible to send CSI-RS together, i.e. HARQ-ACK/CSI report + DMRS + CSI-RS;

i.e. the RLM-RS may be a sequence based HARQ-ACK or a DMRS or CSI-RS.

For the sending UE, a period for reporting link quality by the UE is set, and in this period, the UE physical layer needs to report an AS layer and a link quality indicator (i.e., the above-mentioned direct link state).

Wherein, the reported link quality has 3 states, In-sync, Out-of-sync and None (or nothing is reported);

similar to the receiving UE, for reporting In-sync and Out-of-sync; or, if the ACK or NACK carried on the PSFCH sent by at least one second terminal is received, the state is in the in-synchronization state, and if the signal carried on the PSFCH sent by any second terminal is not received, the state is in the out-of-synchronization state. Or, if receiving ACK carried on the PSFCH sent by at least one second terminal or receiving NACK carried on the PSFCH sent by less than M second terminals, the state is a synchronization state; and if NACK carried on the PSFCH sent by more than or equal to M second terminals is received, the state is in an out-of-step state, and M is a positive integer more than or equal to 1.

For reporting a None (or nothing), since the sending UE explicitly knows whether there is a PSFCH sent by the receiving UE in the period, since the time interval between the PSFCH and a Physical downlink shared Channel (psch) is known, where the psch can represent data sent by the sending UE, reporting a None (or nothing) can only be due to the fact that there is no PSFCH sent by the receiving UE in the period, i.e., there is no PSFCH signal or RLM-RS.

In addition, the RLM-RS refers to a DMRS, a CSI-RS, or an SSB on the SL port, and the DMRS, the CSI-RS, or the SSB is transmitted along with the PSFCH on the SL port, and thus, if the receiving UE does not transmit the PSFCH, the RLM-RS is not transmitted.

Therefore, for the RLF process of the sending UE, the None (or nothing reporting) status does not count the counters of In-sync and Out-of-sync, and the specific process is shown In the reporting flow shown In fig. 6, where the parameters In the flow, including N4, T4, N44, may be configured by the network, or by pre-configuration, or by other UEs to the sending UE, where other terminals may be the receiving UE, the control UE, the group head or cluster head UE, the management UE In the UE group, and the like.

It should be noted that the flows shown in fig. 3 to fig. 6 may be described by taking a unicast service in the NR direct connection system as an example, and the multicast services are similar and will not be described again here.

It should be noted that various optional implementations provided in the embodiment of the present invention may be implemented in combination with each other, or may be implemented separately, which is not limited herein.

In the embodiment of the invention, a first terminal monitors the quality of a direct link to obtain the state of the direct link, wherein the direct link is between the first terminal and a second terminal; when the direct link state is a first state, the first terminal reports the direct link state to an access layer of the first terminal; and under the condition that the direct link state is the second state, the first terminal reports the direct link state to an access layer of the first terminal, or indicates the direct link state by not reporting the direct link state to the access layer. Therefore, the link monitoring of the direct link supporting the unicast or multicast service can be realized, the monitoring effect of the direct link is improved, and the transmission performance of the unicast or multicast service can be further improved. Furthermore, the method can be suitable for the direct link characteristics of unicast or multicast services in the NR system, thereby improving the monitoring effect of the direct link.

Referring to fig. 7, fig. 7 is a structural diagram of a terminal according to an embodiment of the present invention, where the terminal is a first terminal, and as shown in fig. 7, a terminal 700 includes:

a monitoring module 701, configured to monitor quality of a direct link, to obtain a state of the direct link, where the direct link is a direct link between the first terminal and a second terminal;

Optionally, as shown in fig. 8, the first terminal further includes:

a reporting module 702, configured to report, to a higher layer of the terminal, a radio link failure RLF according to the direct link status received by the access layer.

Optionally, as shown in fig. 9, the reporting module includes at least one of the following:

a first reporting unit 7021, configured to start a first timer if the access stratum continuously receives N1 out-of-sync states, and perform RLF reporting to a higher layer of the first terminal when the first timer is overtime, where a condition that the first timer stops includes that the access stratum continuously receives N11 out-of-sync states;

a second reporting unit 7022, configured to start a second timer if the access stratum continuously receives N2 None states, and perform RLF reporting to a higher layer of the first terminal if the second timer is overtime, where a condition that the second timer stops includes that the access stratum continuously receives N22 synchronization states;

a third reporting unit 7023, configured to start a third timer if the access stratum continuously receives N3 states, and report an RLF to a higher layer of the first terminal when the third timer expires, where a condition that the third timer stops includes that the access stratum continuously receives N33 synchronization states, and N3 is a sum of numbers of out-of-synchronization states and None states;

Optionally, if a PSCCH signal sent by at least one second terminal is received, the PSCCH signal is in a synchronous state; if the PSCCH signal sent by any second terminal is not received, the state is in an out-of-step state or in a None state; alternatively, the first and second electrodes may be,

if receiving the ACK carried on the PSFCH sent by at least one second terminal or receiving NACK carried on the PSFCH sent by less than M second terminals, the state is a synchronous state; and if NACK carried on the PSFCH sent by more than or equal to M second terminals is received, the state is in an out-of-step state, and M is a positive integer more than or equal to 1.

Optionally, the reporting module 702 is configured to start a fourth timer if the access stratum continuously receives N4 out-of-sync states, and perform RLF reporting to a higher layer of the first terminal if the fourth timer expires, where a condition that the fourth timer stops includes that the access stratum continuously receives N44 in-sync states, where N4 and N44 are positive integers.

Optionally, the monitoring module 701 is configured to, when the first terminal is a receiving end on the direct link, monitor, by the first terminal, a PSCCH signal or an RLM-RS that is sent by the second terminal on the direct link; or alternatively

In the case that the first terminal is a transmitting end on the direct link, the monitoring module 701 monitors, by the first terminal, a PSFCH signal or an RLM-RS transmitted by the second terminal on the direct link.

Optionally, the RLM-RS includes at least one of:

HARQ-ACK、DMRS、CSI-RS、SSB。

the first terminal provided in the embodiment of the present invention can implement each process in the method embodiment shown in fig. 2, and can obtain the same beneficial effect, which is not described herein again to avoid repetition.

Referring to fig. 10, fig. 10 is a structural diagram of another terminal according to an embodiment of the present invention, where the terminal is a first terminal, and as shown in fig. 10, the first terminal includes: a transceiver 1010, a memory 1020, a processor 1000, and a program stored on the memory 1020 and executable on the processor 1000, wherein:

the transceiver 1010 is configured to monitor the quality of a direct link, and obtain a state of the direct link, where the direct link is a direct link between the first terminal and a second terminal;

wherein, when the direct link status is the first status, the transceiver 1010 or the processor 1000 is configured to report the direct link status to an access layer of the first terminal; alternatively, the first and second electrodes may be,

Among other things, the transceiver 1010 may be used to receive and transmit data under the control of the processor 1000.

In FIG. 10, the bus architecture may include any number of interconnected buses and bridges, with various circuits being linked together, in particular, one or more processors, represented by processor 1000, and a memory, represented by memory 1020. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1010 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium.

The processor 1000 is responsible for managing the bus architecture and general processing, and the memory 1020 may store data used by the processor 1000 in performing operations.

It should be noted that the memory 1020 is not limited to be located on the first terminal, and the memory 1020 and the processor 1000 may be separated in different geographical locations.

Optionally, the transceiver 1010 or the processor 1000 is further configured to:

Optionally, when the first terminal is a receiving end on the direct link, the reporting of the radio link failure RLF to the higher layer of the first terminal according to the direct link state received by the access layer includes at least one of:

Optionally, the reporting the direct link status to the access layer of the first terminal includes:

and periodically reporting the direct link state to an access layer of the first terminal.

Optionally, the monitoring the quality of the direct link includes:

monitoring a PSCCH signal or RLM-RS sent by the second terminal on the direct link under the condition that the first terminal is a receiving end on the direct link; or

And monitoring a PSFCH signal or RLM-RS sent by the second terminal on the direct link under the condition that the first terminal is a sending end on the direct link.

Optionally, the RLM-RS includes at least one of:

HARQ-ACK、DMRS、CSI-RS、SSB。

it should be noted that, in this embodiment, the first terminal may be a first terminal in any implementation manner in the method embodiment of the present invention, and any implementation manner of the first terminal in the method embodiment of the present invention may be implemented by the first terminal in this embodiment, so as to achieve the same beneficial effects, and details are not described here again.

In the several embodiments provided in the present application, it should be understood that the disclosed method and apparatus may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

In addition, functional units in the embodiments of the present invention may be integrated into one processing unit, or each unit may be physically included alone, or two or more units may be integrated into one unit. The integrated unit can be realized in a form of hardware, or in a form of hardware plus a software functional unit.

The integrated unit implemented in the form of a software functional unit may be stored in a computer readable storage medium. The software functional unit is stored in a storage medium and includes several instructions to enable a computer device (which may be a personal computer, a server, or a network device) to execute some steps of the transmission method of the direct link according to various embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A method for monitoring a direct link, comprising:

when the through link state is the second state, the first terminal reports the through link state to an access layer of the first terminal, or indicates the through link state by not reporting the through link state to the access layer;

the first state comprises a synchronous state or an out-of-step state; the second state comprises an invalid None state, wherein the direct link state is the None state when the first terminal does not receive a signal sent by the second terminal;

the method further comprises the following steps:

and the first terminal reports the Radio Link Failure (RLF) to the high layer of the first terminal according to the direct link state received by the access layer.

2. The method of claim 1, wherein, in a case that the first terminal is a receiving end on the direct link, the first terminal performs RLF reporting to a higher layer of the first terminal according to the direct link status received by the access stratum, and the RLF reporting includes at least one of:

wherein, N1, N2, N3, N11, N22 and N33 are positive integers, N33 is greater than or equal to N22, and N22 is greater than or equal to N11.

3. The method of claim 2, wherein at least one of the duration of the first timer, the duration of the second timer, the duration of the third timer, N1, N2, N3, N11, N22, and N33 is: pre-configured, protocol pre-defined or network side configured or configured by other terminals, wherein the other terminals comprise:

4. The method of claim 1, wherein, when the first terminal is a transmitting end on the direct link, the RLF reporting is performed by the first terminal to a higher layer of the first terminal according to the direct link status received by the access stratum, and the RLF reporting includes:

if the access stratum continuously receives N4 out-of-sync states, starting a fourth timer, and reporting to a higher layer of the first terminal through an RLF (radio link failure) under the condition that the fourth timer is overtime, where a condition that the fourth timer stops includes that the access stratum continuously receives N44 in-sync states, where N4 and N44 are positive integers.

5. The method of claim 4, wherein at least one of a duration of the fourth timer, N4, and N44 is: pre-configured, protocol pre-defined or network side configured or configured by other terminals, wherein the other terminals comprise:

6. The method according to any of claims 1 to 5, characterized in that if a direct link physical control channel (PSCCH) signal transmitted by at least one second terminal is received, it is in a synchronous state; if the PSCCH signal sent by any second terminal is not received, the state is in an out-of-step state or in a None state; alternatively, the first and second electrodes may be,

if receiving ACK or NACK carried on PSFCH sent by at least one second terminal, the state is synchronous; if the signal carried on the PSFCH sent by any second terminal is not received, the state is in an out-of-step state; alternatively, the first and second liquid crystal display panels may be,

7. The method of any one of claims 1 to 5, wherein reporting, by the first terminal, the direct link status to an access stratum of the first terminal comprises:

8. The method of any of claims 1 to 5, wherein the first terminal monitoring a through link quality comprises:

when the first terminal is a receiving end on the direct link, the first terminal monitors a PSCCH signal or a radio link monitoring reference signal RLM-RS sent by the second terminal on the direct link; or

And under the condition that the first terminal is a sending end on the direct link, the first terminal monitors a direct link feedback channel PSFCH signal or RLM-RS sent by the second terminal on the direct link.

9. The method of claim 8, wherein the RLM-RS comprises at least one of:

the method comprises the steps of hybrid automatic repeat request acknowledgement HARQ-ACK based on sequences, demodulation reference signals DMRS, channel state information reference signals CSI-RS and a synchronous signal block SSB.

10. A terminal, the terminal being a first terminal, comprising:

the first state comprises a synchronous state or an out-of-step state; the second state comprises a None state, wherein the direct link state is the None state when the first terminal does not receive a signal sent by the second terminal;

the first terminal further comprises:

and a reporting module, configured to report, to a higher layer of the terminal, a radio link failure RLF according to the direct link state received by the access layer.

11. The terminal of claim 10, wherein the reporting module comprises at least one of:

a second reporting unit, configured to start a second timer if the access stratum continuously receives N2 None states, and perform RLF reporting to a higher layer of the first terminal when the second timer expires, where a condition that the second timer stops includes that the access stratum continuously receives N22 synchronization states;

12. The terminal of claim 10, wherein the reporting module is configured to start a fourth timer if the access stratum continuously receives N4 out-of-sync states, and perform RLF reporting to the higher layer of the first terminal if the fourth timer expires, wherein a condition for the fourth timer to stop includes that the access stratum continuously receives N44 in-sync states, and wherein N4 and N44 are positive integers.

13. A terminal, the terminal being a first terminal comprising: a transceiver, a memory, a processor, and a program stored on the memory and executable on the processor,

when the direct link state is the second state, the transceiver or the processor is configured to report the direct link state to an access layer of the first terminal, or indicate the direct link state by not reporting the direct link state to the access layer;

the transceiver or the processor is further configured to:

and according to the direct link state received by the access layer, RLF reporting is carried out to the high layer of the first terminal.

14. The terminal of claim 13, wherein, in a case that the first terminal is a receiving end on the direct link, the performing RLF reporting to a higher layer of the first terminal according to the direct link status received by the access stratum comprises at least one of:

15. The terminal of claim 13, wherein, when the first terminal is a sender on the direct link, the performing RLF reporting to a higher layer of the first terminal according to the direct link status received by the access stratum comprises:

16. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps in the direct link monitoring method according to any one of claims 1 to 9.