CN116456444A - Propagation delay compensation method and device - Google Patents

Abstract

The embodiment of the application provides a propagation delay compensation method and device. The network device determines a first message and sends the first message to the terminal device, where the first message is used to indicate whether the network device allows the terminal device to perform propagation delay compensation PDC for a time T, where the time T is a reference time indicated by the network device to the terminal device for air interface time synchronization. The terminal equipment receives a first message from the network equipment, and determines whether PDC is allowed to be carried out on the time T or not according to the first message; and when the PDC is allowed to be performed on the time T, performing PDC on the time T according to the configuration condition of RTT measurement. The method can realize that the network equipment controls the terminal equipment to carry out PDC, enhances the matching degree of the time synchronization of the terminal equipment and the network equipment, can avoid the reduction of the accuracy of the time synchronization caused by the PDC carried out by the terminal equipment and the network equipment, and is beneficial to realizing the high-accuracy time synchronization between the terminal equipment and the network equipment.

Description

Propagation delay compensation method and device

technical field

The present application relates to the field of communication technologies, and in particular to a propagation delay compensation method and device.

Background technique

In a time-sensitive network (time sensitive network, TSN), in order to support time-based operation control, it is necessary to maintain time synchronization between TSN devices. In the 3rd generation partnership project (3rd generation partnership project, 3GPP) Rel-16, a solution for a 5G system (5G system, 5GS) to support TSN is proposed, that is, 5GS is used as a TSN bridge device. Specifically, in 5GS, a user plane function (User Plane Function, UPF) network element receives a message from a TSN device, and a terminal device forwards the message to other TSN devices.

Among them, when the TSN network uses a high-precision time synchronization protocol (precision time protocol, PTP) to ensure high-precision time synchronization, 5GS can be used as a transparent clock in PTP, and it is necessary to calculate the stay time of PTP messages in 5GS, that is, UPF receives information from TSN equipment The time difference between the time of the PTP message and the time when the terminal device sends the PTP message to other TSN devices. It can be seen that time synchronization needs to be maintained between the UPF and the terminal equipment. The time synchronization between the terminal equipment and the UPF can be guaranteed by obtaining the time from the same clock source. Specifically, the terminal device and the UPF can respectively maintain time synchronization with the network device, so as to realize time synchronization between the terminal device and the UPF. Among them, the time synchronization between the UPF and the network equipment can be realized based on PTP. Then, how to realize the time synchronization between the terminal device and the network device is an urgent problem to be solved.

Contents of the invention

Embodiments of the present application provide a propagation delay compensation method and device, which are beneficial to realize time synchronization between a terminal device and a network device.

In a first aspect, the present application provides a propagation delay compensation method, which includes: a terminal device receives a first message from a network device, and the first message is used to indicate whether the network device allows the terminal device to perform propagation delay for time T Compensation (propagation delay compensation, PDC); time T is the reference time for air interface time synchronization indicated by the network device to the terminal device; the terminal device determines whether it is allowed to perform PDC on time T according to the first message; the terminal device determines that it is allowed When the PDC is performed on the time T, the PDC is performed on the time T according to the configuration of the round-trip time delay (round-trip-time, RTT) measurement.

It can be seen that the terminal device can determine whether it is allowed to perform PDC on the time T based on the indication of the network device, which effectively enhances the degree of cooperation between the terminal device and the network device for time synchronization, thereby preventing both the terminal device and the network device from performing PDC. As a result, the accuracy of time synchronization is reduced, and the terminal device can flexibly select the PDC mode based on the configuration of the RTT measurement, which is conducive to realizing high-precision time synchronization between the terminal device and the network device.

In an optional implementation manner, the terminal device determines whether to perform PDC on time T according to the first message, including: the terminal device includes the first field in the first message and the first field indicates enable ( enable), determine that the terminal device is allowed to perform PDC on time T; the terminal device determines that the terminal device is prohibited from performing PDC on time T when the first message includes the first field and the first field indicates disable (disable). PDC. It can be seen that in this embodiment, the terminal device can determine whether to perform PDC on the time T based on the indication of the first field, which effectively enhances the degree of cooperation between the terminal device and the network device for time synchronization.

Optionally, the method may further include: when the first message does not include the first field, the terminal device performs PDC according to a preset PDC manner.

In an optional implementation manner, when the terminal device determines that it is allowed to perform the PDC on the time T, it performs the PDC on the time T according to the configuration of the RTT measurement, including: when the terminal device is configured with the round-trip delay RTT measurement, based on the RTT The PDC is performed on the time T; when the RTT measurement is not configured, the terminal device performs the PDC on the time T based on a timing advance (timing advance, TA). It can be seen that this embodiment clarifies the relevant behavior when the terminal device is allowed to perform PDC for the time T. Moreover, the PDC method determined by the terminal device based on whether RTT measurement is configured can better meet the actual situation of the terminal device for PDC requirements, thereby effectively improving the accuracy of time synchronization between the terminal device and the network device.

In an optional implementation manner, when the terminal device determines that it is allowed to perform PDC on the time T, it performs the PDC on the time T according to the configuration of the RTT measurement, including: when the terminal device is configured with the round-trip delay RTT measurement and there is a When the round-trip delay RTT measurement result is used, PDC is performed on the time T based on the RTT measurement result; when the terminal device is configured with the round-trip delay RTT measurement result and there is no available round-trip delay RTT measurement result, it determines not to perform the time T PDC, or, when receiving a usable RTT measurement result, perform PDC on time T based on the RTT measurement result; when RTT measurement is not configured, the terminal device performs PDC on time T based on timing advance TA.

It can be seen that this embodiment clarifies the relevant behavior when the terminal device is allowed to perform PDC for the time T. In addition, the terminal device uses whether RTT measurement is configured and whether there is a usable RTT measurement result as a switch to determine the PDC mode. Compared with the method of determining the PDC mode only based on whether RTT measurement is configured, it also fully considers the configuration of the terminal device. When the RTT measurement is performed and there is no usable RTT measurement result, the accuracy of time synchronization between the terminal device and the network device can be effectively improved.

In an optional implementation manner, when the terminal device determines that it is allowed to perform the PDC on the time T, it performs the PDC on the time T according to the configuration of the RTT measurement, including: when the terminal device is configured with the round-trip delay RTT measurement and exists When the RTT measurement result is within the validity period, PDC is performed on time T based on the RTT measurement result; when the terminal device is configured with round-trip delay RTT measurement and the existing RTT measurement result is not within the validity period, it determines not to perform PDC on time T, or, When the RTT measurement result is received within the preset duration, the PDC is performed on the time T based on the received RTT measurement result; when the RTT measurement is not configured, the terminal device performs the PDC on the time T based on the timing advance TA.

It can be seen that this embodiment clarifies the relevant behavior when the terminal device is allowed to perform PDC for the time T. In addition, the terminal device uses whether RTT measurement is configured and whether the existing RTT measurement result is within the validity period as a switch to determine the PDC method. Compared with the method of determining the PDC method based only on whether RTT measurement is configured, the terminal device also fully considers When the RTT measurement is configured and the RTT measurement result exceeds the validity period, the accuracy of time synchronization between the terminal device and the network device can be effectively improved.

In an optional implementation manner, whether the RTT measurement result is within the validity period is determined by the terminal device through a timer.

In an optional implementation manner, when the terminal device determines that it is forbidden to perform PDC on the time T, the method further includes: when the round-trip delay RTT measurement is configured, the terminal device sends to the network device the latest reception of the terminal device- Sending time difference. This embodiment is beneficial for the network device to perform PDC based on the receiving-sending time difference of the latest terminal device.

In a second aspect, the present application provides a propagation delay compensation method, which includes: a network device determines a first message, and the first message is used to indicate whether the network device allows the terminal device to perform propagation delay compensation PDC for time T; time T is the reference time for air interface time synchronization indicated by the network device to the terminal device: the network device sends the first message to the terminal device.

It can be seen that the network device can indicate whether the terminal device is allowed to perform PDC on the time T, so that the terminal device can perform PDC on the time T based on the instruction of the network device, so that the network device can control the terminal device to perform PDC, effectively enhancing the terminal device and network device. The degree of cooperation between the time synchronization can avoid the reduction of the accuracy of time synchronization caused by both the network device and the terminal device performing PDC, which is conducive to the realization of high-precision time synchronization between the network device and the terminal device.

In an optional implementation manner, the first message includes a first field; when the network device allows the terminal device to perform PDC on time T, the first field indicates enable; when the network device prohibits the terminal device from performing PDC on time T, The first field indicates that disable is not enabled; the second indication is used for the terminal device to determine the PDC mode. Optionally, when the network device does not indicate whether the terminal device is allowed to perform the PDC on the time T or is prohibited from performing the PDC on the time T, the first message does not include the first field.

In an optional implementation manner, the network device is a structure in which a distributed unit (distributed unit, DU) and a centralized unit (central unit, CU) are separated, and the network device determines the first message, including: the CU sends the DU to the The second message, where the second message includes the default format of the first message; when the DU receives the second message, it determines the first message. The network device sending the first message to the terminal device includes: the DU sending the first message to the terminal device, where the first line message is a radio resource control (radio resource control, RRC) broadcast message. It can be seen that this embodiment can be applied in a broadcasting scenario, and the DU decides whether to allow the terminal device to perform PDC on the time T, that is, whether to allow the terminal device to perform the PDC on the time T.

In an optional implementation manner, the network device is a structure in which the DU and the CU are separated, and the network device determines the first message, including: the DU sends a second message to the CU, and the second message includes the first field in the first message The value of ; when the CU receives the second message, determine the first message. The network device sending the first message to the terminal device includes: the CU sending the first message to the terminal device, where the first message is a radio resource control RRC unicast message. It can be seen that this embodiment can be applied in a unicast scenario, and the DU decides whether to allow the terminal device to perform PDC on the time T, that is, whether to allow the terminal device to perform the PDC on the time T.

In an optional implementation manner, the network device is a structure in which the distributed unit DU and the centralized unit CU are separated, and the network device determines the first message, including: the DU sends a second message to the CU, and the second message includes the time The value of T and the value of PDC; the CU determines the first message according to the value of time T and the value of PDC. The network device sending the first message to the terminal device includes: the CU sending the first message to the terminal device, where the first message is a radio resource control RRC unicast message. It can be seen that this implementation manner can be applied in a unicast scenario, and the CU decides whether to allow the terminal device to perform PDC on the time T, that is, whether to allow the terminal device to perform the PDC on the time T.

In a third aspect, the present application provides a communication device, and the beneficial effects may refer to the description of the first aspect, which will not be repeated here. The communication device has the function of implementing the actions in the method example of the first aspect above. The functions described above may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In a possible design, the terminal device includes: a communication unit, configured to receive a first message from the network device, where the first message is used to indicate whether the network device allows the communication device to perform propagation delay compensation PDC for the time T; Time T is the reference time for air interface time synchronization indicated by the network device to the communication device; the processing unit is used to determine whether to allow PDC for time T according to the first message; the processing unit is also used to determine whether it is allowed to perform PDC for time T When T performs PDC, perform PDC on time T according to the configuration of RTT measurement.

These modules can perform the corresponding functions in the method example of the first aspect above. For details, refer to the detailed description in the method example, and details are not repeated here.

In a fourth aspect, the present application provides a communication device, and the beneficial effects may refer to the description of the second aspect, which will not be repeated here. The communication device has the function of implementing the actions in the method example of the second aspect above. The functions described above may be implemented by hardware, or may be implemented by executing corresponding software on the hardware. The hardware or software includes one or more modules corresponding to the above functions.

In a possible design, the communication device includes: a processing unit, configured to determine a first message, and the first message is used to indicate whether the communication device allows the terminal device to perform propagation delay compensation PDC for time T; time T is communication A reference time for air interface time synchronization indicated by the device to the terminal device; a communication unit configured to send the first message to the terminal device.

These modules can perform the corresponding functions in the method example of the second aspect above. For details, refer to the detailed description in the method example, and details are not repeated here.

In a fifth aspect, the present application provides a communication device, including a memory and a processor. Wherein, the memory is used to store instructions or computer programs; the processor is used to execute the computer programs or instructions stored in the memory, so that the communication device executes the method described in the first aspect, or executes the method described in the second aspect.

In a sixth aspect, the present application provides a computer-readable storage medium, which is used to store a computer program, and when the computer program is run on a computer, it causes the computer to execute the method described in the first aspect, or to execute the method described in the second aspect. method.

In a seventh aspect, an embodiment of the present application provides a chip or a chip system, the chip or chip system includes at least one processor and an interface, the interface and the at least one processor are interconnected through a line, and the at least one processor is used to run computer programs or instructions, To execute the method described in the first aspect, or to execute the method described in the second aspect.

Wherein, the interface in the chip may be an input/output interface, a pin or a circuit, and the like.

The chip system in the above aspect may be a system on chip (system on chip, SOC), or a baseband chip, etc., where the baseband chip may include a processor, a channel encoder, a digital signal processor, a modem, and an interface module.

In a possible implementation, the chip or the chip system described above in the present application further includes at least one memory, and instructions are stored in the at least one memory. The memory may be a storage unit inside the chip, such as a register, a cache, etc., or a storage unit of the chip (eg, a read-only memory, a random access memory, etc.).

In an eighth aspect, the present application provides a computer program or a computer program product, including computer instructions, when the computer instructions are run on a computer, the computer is made to execute the method described in the first aspect, or to execute the second aspect the method described.

Description of drawings

Fig. 1a is a schematic structural diagram of a communication system provided by an embodiment of the present application;

Fig. 1b is a schematic structural diagram of a system architecture provided by an embodiment of the present application;

Fig. 1c is a schematic structural diagram of another system architecture provided by an embodiment of the present application;

FIG. 2 is a schematic diagram of a clock node provided by an embodiment of the present application;

FIG. 3 is a schematic diagram of a 5GS as a TSN bridging device provided by an embodiment of the present application;

Fig. 4 is a schematic diagram of a 5GS as a transparent clock provided by the embodiment of the present application;

FIG. 5 is a schematic diagram of a unicast indication of 5G time provided by an embodiment of the present application;

FIG. 6 is a schematic diagram of a TA-based PDC method provided by an embodiment of the present application;

Fig. 7a is a schematic diagram of an RTT-based PDC method provided by an embodiment of the present application;

Fig. 7b is a schematic diagram of another RTT-based PDC method provided by the embodiment of the present application;

FIG. 8 is a schematic flowchart of a propagation delay compensation method provided by an embodiment of the present application;

FIG. 9 is a schematic diagram of a timer running process provided by an embodiment of the present application;

Fig. 10a is a schematic diagram of an exemplary propagation delay compensation method provided by an embodiment of the present application;

Fig. 10b is a schematic diagram of another exemplary propagation delay compensation method provided by an embodiment of the present application;

Fig. 10c is a schematic diagram of another exemplary propagation delay compensation method provided by an embodiment of the present application;

Fig. 11 is a schematic diagram of a first indication and a second indication provided by an embodiment of the present application;

FIG. 12 is a schematic diagram of a side link communication scenario provided by an embodiment of the present application;

Fig. 13 is a schematic structural diagram of a communication device provided by an embodiment of the present application;

FIG. 14 is a schematic structural diagram of another communication device provided by an embodiment of the present application;

FIG. 15 is a schematic structural diagram of a chip provided by an embodiment of the present application.

Detailed ways

Embodiments of the present application are described below with reference to the drawings in the embodiments of the present application.

First, in order to better understand the propagation delay compensation method disclosed in the embodiment of the present application, the communication system to which the embodiment of the present application is applicable is described.

The technical solutions of the embodiments of the present application can be applied to various communication systems. For example, Global System for Mobile Communications, Long Term Evolution (LTE) system, Fourth Generation (4th-Generation, 4G) mobile communication technology system, New Generation Radio Access Technology (New Radio, NR) system, and with With the continuous development of communication technology, the technical solution of the embodiment of the present application can also be used in subsequent evolution communication systems, such as the sixth generation (6th-Generation, 6G) mobile communication technology system, the seventh generation (7th-Generation, 7G) mobile communication system technology systems and more.

Please refer to FIG. 1a. FIG. 1a is a schematic structural diagram of a communication system provided by an embodiment of the present application. The communication system may include but not limited to a network device and a terminal device. Wherein, the network device and the terminal device may communicate through a wireless connection, for example, the network device and the terminal device may communicate through a Uu interface. The number and form of devices shown in FIG. 1a are for example and do not constitute a limitation to the embodiment of the present application. In practical applications, two or more network devices and two or more terminal devices may be included. The communication system shown in FIG. 1a is described by taking a network device and a terminal device as an example. In Fig. 1a, a network device is taken as an example of a base station, and a terminal device is taken as an example of a mobile phone.

In the embodiment of the present application, the network device is an access network device, which may be a radio access network (radio access network, RAN) node (or called a radio access network device) that connects a terminal device to a wireless network. The equipment includes but not limited to: evolved node B (evolved node B, eNB), radio network controller (radio network controller, RNC), node B (Node B, NB), network device controller (base station controller, BSC), Network equipment transceiver station (base transceiver station, BTS), home network equipment (for example, home evolvedNode B, or home Node B, HNB), baseband unit (baseband unit, BBU), wireless fidelity (wirelessfidelity, WIFI) system in Access point (access point, AP), wireless relay node, wireless backhaul node, transmission and reception point (TRP), transmission point (transmission point, TP), etc.; it can also be the fifth generation (5th- Generation, 5G), equipment used in 6G and even 7G systems, such as gNB in NR system, or transmission point (TRP or TP), one or a group (including multiple antenna panels) of network equipment in 5G system antenna panels , or, it can also be a network node that constitutes a gNB or a transmission point, such as a baseband unit (BBU), or a distributed unit (DU), or a vehicle to everything (V2X) or intelligent driving scene Road side unit (road side unit, RSU).

In some deployments, network devices may include centralized units (centralized units, CUs), DUs, and the like. The network device may also include a radio frequency unit (radio unit, RU). Among them, the CU implements some functions of the network equipment, and the DU implements some functions of the network equipment. For example, the CU implements radio resource control (radio resource control, RRC), packet data convergence protocol (packet data convergence protocol, PDCP) layer functions, The DU implements the functions of radio link control (radio link control, RLC), media access control (media access control, MAC) and physical (physical, PHY) layer. Because the information of the RRC layer will eventually become the information of the physical layer, or be converted from the information of the physical layer, therefore, under this framework, high-level signaling, such as RRC layer signaling or PDCP layer signaling, can also be It is considered to be sent by DU, or sent by DU+RU. It can be understood that the network device may be a CU node, or a DU node, or a device including a CU and a DU.

Wherein, when the network device is a device including a CU and a DU and performs broadcast communication, it can communicate with a terminal device through the DU, as shown in FIG. 1b. When the network device is a device including CU and DU and performs unicast communication, the data sent by the network device to the terminal device must be encrypted by the CU before being sent to the terminal device. Therefore, the network device communicates with the terminal device through the CU, as shown in Figure 1c shown.

In this embodiment of the present application, the terminal device may be a device that provides voice and/or data connectivity to a user. Terminal equipment may also be called user equipment (user equipment, UE), terminal, access terminal, subscriber unit, subscriber station, mobile station, mobile station (mobile station, MS), mobile terminal (mobile terminal, MT), remote station , remote terminal, mobile device, user terminal, user agent or user device, which can be applied to 4G, 5G or even 6G systems. The terminal device in the embodiment of the present application may be a joint device for transmitting and receiving digital signals on an ordinary telephone line, or it may be a mobile phone, a tablet computer (Pad), a computer with a wireless transceiver function, a virtual reality (virtual reality) reality, VR) terminal equipment, augmented reality (augmented reality, AR) terminal equipment, wireless terminals in industrial control (industrial control), wireless terminals in self-driving (self driving), wireless terminals in remote medical (remotemedical), Wireless terminals in smart grid, wireless terminals in transportation safety, wireless terminals in smart city, wireless terminals in smart home, RSUs of the aforementioned wireless terminal types etc. The terminal device may also be a device capable of sidelink (sidelink) communication, for example, the terminal device may be a vehicle-mounted terminal, or a handheld terminal capable of V2X communication.

In order to facilitate understanding of the embodiments disclosed in the present application, the following two points are explained.

(1) The scenarios in the embodiments disclosed in the present application are described by taking the scenario of the NR network in the wireless communication network as an example. It should be pointed out that the solutions in the embodiments disclosed in the present application can also be applied to other wireless communication networks. The name of can also be replaced by the name of the corresponding function in other wireless communication networks.

(2) Embodiments disclosed in the application will present various aspects, embodiments or features of the application around a system including a plurality of devices, components, modules, and the like. It is to be understood and appreciated that the various systems may include additional devices, components, modules, etc. and/or may not include all of the devices, components, modules etc. discussed in connection with the figures. Additionally, combinations of these schemes can also be used.

Secondly, a brief introduction is given to related concepts involved in the embodiments of the present application.

1. Precision time protocol (PTP)

PTP is a protocol that can be used to implement precise time synchronization (timing synchronization) between devices, and the time synchronization based on PTP can achieve sub-microsecond precision. Wherein, time synchronization may also be referred to as clock synchronization. For time synchronization, three basic types of clock nodes are defined in PTP, including: ordinary clock (ordinary, clock, OC), boundary clock (boundary, clock, BC) and transparent clock (transparent, clock, TC). The three types of clock nodes are introduced below:

(1) There is only one clock port in OC, which can be used to communicate with other clocks in the network. The OC can be used as a master clock (grandmaster clock, GM) or a slave clock (slave clock, SC). Among them, GM refers to a clock used to issue time information to downstream nodes; SC refers to a clock that synchronizes time with upstream nodes based on received time information from upstream nodes. Wherein, the time information in the process of time synchronization based on PTP may be carried in a PTP message. For example, when clock 1 sends time information to clock 2 to implement time synchronization between clock 1 and clock 2, clock 1 is the upstream node and clock 2 is the downstream node.

In addition, the GM can issue time information to downstream nodes through the master clock port (ie, the M port), and the SC can receive time information from the upstream node through the slave clock port (ie, the S port). For example, referring to FIG. 2 , in FIG. 2 , OC-1 serves as a master clock, and OC-2, OC-3, and OC-4 all serve as slave clocks.

(2) Multiple clock ports exist in BC, and each clock port can be used to communicate with other clocks in the network. Among the multiple clock ports of the BC, there is a clock port for synchronizing time with the upstream node, and other clock ports are used for publishing time information to the downstream nodes. For example, in combination with Figure 2, BC-1 includes port 1, port 2, and port 3; among them, port 1 is an S port, which can be used for BC-1 to receive time information from TC-1; port 2 and port 3 are both M ports , Port 2 can be used for BC-1 to send time information to OC-2, and port 3 can be used for BC-1 to send time information to TC-2.

In addition, BC needs to maintain time synchronization with other clocks. Specifically, after the BC receives the PTP message from the upstream node, it will synchronize the time with the upstream node based on the PTP message, but will not directly forward the received PTP message, but will generate a new PTP message based on the PTP message, Then send the new PTP message to the downstream node. For example, in conjunction with Fig. 2, after BC-1 receives the PTP message from TC-1 through the S port (ie port 1), it synchronizes time with OC-1 based on the PTP message, and generates a new PTP message based on the PTP message, and then Send a new PTP message to OC-2 through the M port (ie, port 2).

(3) Multiple clock ports exist in the TC, and these clock ports are used to forward PTP messages. The TC can correct the forwarding delay of the PTP message, and the TC does not need to keep time synchronization with other clocks. Specifically, the TC performs forwarding delay correction on the PTP message, which may include: the TC configures the correction field (correctionField) field of the PTP message, and the correctionField field is used to indicate the stay time of the PTP message at the local node. Dwell time may also be referred to as a correction value. Therefore, after receiving the PTP message, the downstream node of the TC can perform time synchronization based on the time information carried in the PTP message and the correction value indicated by the correctionField field. For example, referring to FIG. 2 , TC-1 receives a PTP message from OC-1, corrects the forwarding delay of the PTP message, and sends it to BC-1.

2. Time sensitive network (TSN)

TSN can be applied to industrial control scenarios. In the industrial control scenario, the control signaling sent by the master node (such as the console) can reach the slave node (such as the operating arm) within a specified time, and the slave node can perform the corresponding operation at the specified time point. It can be seen that the industrial control network usually is a TSN. TSN usually uses a high-precision time synchronization protocol to achieve precise time synchronization between TSN devices, thereby supporting time-based operation control. Wherein, the high-precision time synchronization protocol may be PTP, or the Institute of Electrical and Electronics Engineers (Institute of Electrical and Electronics Engineers, IEEE) 1588 protocol.

It can be seen that in scenarios such as industrial manufacturing, product line control is usually performed through TSN. At present, TSN is basically carried on the wired network, but the TSN based on the wired network has inherent defects such as high cable deployment costs, security risks, and low flexibility. Deploying TSN based on the wireless method can effectively avoid the above problems, especially when the last hop of the TSN network adopts a wireless method, that is, a wireless connection is used between the TSN device and the terminal device. In the 3rd generation partnership project (3rd generation partnership project, 3GPP) Rel-16, the scheme of 5G system (5G system, 5GS) supporting TSN is discussed. Combined with Figure 3, in TSN, 5GS can be regarded as a TSN bridge device (TSN bridge), and TSN devices can perform uplink or downlink transmission of TSN service data packets through 5GS. In addition, in the 5GS solution supporting TSN, the time synchronization in TSN requires that the synchronization error between the TSN master clock and the TSN slave clock be within 1 microsecond (us).

In addition, in the solution where the 5G system supports TSN, when TSN uses PTP to achieve precise time synchronization between TSN devices, 5GS and PTP adaptation is also required. In the scheme adopted by 3GPP, 5GS can be regarded as a transparent clock in PTP, then, the PTP message sent by GM in TSN can be forwarded to the TSN network end device through 5GS. In addition, at the border where 5GS and TSN are connected, a TSN adapter needs to be used to process PTP-related messages or data packets. For example, referring to Figure 4, the Device-side TSN Translator (Device-side TSN Translator, DS-TT) (or UE-TT) is the TSN adapter used at the connection between the terminal device and the TSN device in 5GS, and DS-TT can be A processing device connected to the terminal device or a logical function of the terminal device; the network-side TSN adapter (network-side TSN translator, NW-TT) is the user plane function (User Plane Function, UPF) network element in 5GS and TSN The TSN adapter used at the device connection, NW-TT can be a processing device connected to the UPF or a logical function of the UPF.

As a transparent clock, the 5GS needs to obtain the residence time of the PTP message in the 5GS to configure the correctionField field of the PTP message. In order to obtain the residence time of the PTP message in 5GS, it is also necessary to ensure the 5G time synchronization between the terminal equipment and UPF in 5GS. Wherein, the time synchronization between the terminal equipment and the UPF is guaranteed by obtaining the time from the same clock source. Specifically, referring to FIG. 4 , the gNB and the 5G GM perform time synchronization, and the UE and the UPF perform time synchronization with the gNB respectively to realize time synchronization between the UE and the UPF. Among them, UE and gNB can realize clock synchronization through the air interface synchronization scheme, and UPF and gNB can realize clock synchronization through PTP.

The residence time of the PTP message in 5GS is determined based on the 5G time received by the UPF from the TSN device and the 5G time when the terminal device sends the PTP message to the TSN device. In combination with Figure 4, when the NW-TT corresponding to the UPF receives the PTP message from the TSN device, it will stamp the 5G time stamp t _in ; the 5G time for the DS-TT corresponding to the UE to send the PTP message to the TSN device is t _out ; then, The stay time of the PTP message in the 5GS is t _out -t _in .

3.5G air interface time synchronization and propagation delay compensation (propagation delay compensation, PDC)

The 5G air interface time synchronization is realized by indicating a 5G time reference point to the terminal device through the network device. Network devices can provide 5G timing to terminal devices through broadcast or unicast. Wherein, the 5G reference time sent by the network device to the terminal device by broadcasting may be carried by a system information block (SIB) (such as SIB9); the 5G reference time sent by the network device to the terminal device by unicast may be It is carried by a downlink message transfer (DLInformationTransfer) message.

The following takes the network device to provide 5G time service to the terminal device through unicast as an example, and further elaborates on the time synchronization of the 5G air interface. In conjunction with Figure 5, the network device sends a DLInformationTransfer message to the terminal device on a time slot where the System Frame Number (SFN) is x-3 (ie, SFN x-3), and the DLInformationTransfer message carries the time T and the time reference point SFN x. The time T is the time corresponding to the time reference point indicated by the network device to the terminal device; the time reference point may be a certain time position on one or more wireless frames sent by the network device to the terminal device. For example, the time reference point may be the start position or the end position of a certain radio frame. After the terminal device receives the DLInformationTransfer message, it can know that the 5G reference time corresponding to the end position of the radio frame (radio frame) corresponding to the SFN x closest to the moment when the DLInformationTransfer message is received is time T. For example, if the time reference point is the start position of radio frame 1, then, when the terminal device receives the start position of radio frame 1, it may determine that the time corresponding to the start position of radio frame 1 is time T.

PDC can be used for precise time synchronization between devices. When time synchronization is performed between the network device and the terminal device, there is a propagation delay between the network device sending a signal and the terminal device receiving the signal, that is, the frame boundary of the downlink signal sent by the network device and the frame of the downlink signal received by the terminal device There is a time difference between boundaries. Then, in Figure 5, if the time T is the 5G time at the end position of the wireless frame corresponding to the network device sending SFN x, then the terminal device needs to perform PDC in the process of 5G time synchronization based on the unicast timing message, including: based on the time T and the propagation delay to determine the actual 5G time of receiving the end position of the radio frame corresponding to SFN x, that is, the actual 5G time of receiving the end position of the radio frame corresponding to SFN x is the sum of the time T and the propagation delay.

In this embodiment of the application, the terminal device performing PDC means that the terminal device determines the actual time when the terminal device receives the time reference point based on the time T and the propagation delay; the network device performing PDC means that the network device determines that the terminal device receives The actual time at the time reference point. It can be seen that the time T sent by the network device to the terminal device may be the time when the network device has not performed PDC for the time reference point, or it may be the time after performing PDC for the time reference point, that is, the calculated actual time when the terminal device receives the time reference point time. In addition, in this embodiment of the present application, the network device performing PDC may also be referred to as the network device performing PDC pre-compensation.

4. Timing advance (TA) mechanism and TA-based PDC method

The essence of the TA mechanism is that the time for the terminal device to send the uplink subframe is a certain time ahead of the time for receiving the downlink subframe, that is, there is a gap between the start time of the terminal device receiving the downlink subframe and the start time of transmitting the uplink subframe. A negative offset (i.e. TA value). In the orthogonal multiple access system, the network device properly controls the negative offset corresponding to each terminal device based on the TA mechanism to control the time when the uplink signals from different terminal devices arrive at the network device, so that the signals from the same subframe can However, the arrival time of signals of different terminal devices with different frequency domain resources to the network device is basically aligned, thereby ensuring the orthogonality of uplink transmission and avoiding interference in the cell.

Referring to Figure 6, the terminal device sends the uplink signal 2T _p ahead of the time of the frame boundary of the received downlink signal (that is, the ideal TA value); then, the uplink signal reaches the network device after the propagation delay of T _p The time is aligned with the time of the frame boundary of the downlink signal sent by the network device. It can be seen that in this manner, the uplink signals sent by the terminal devices in the cell in the same subframe arrive at the network device at the same time.

The network device may send the TA value to the terminal device through a timing advance command (timing advance command, TAC). Specifically, in the random access process, the network device may indicate the absolute TA value through the TAC field; or, the network device may indicate the TA adjustment value through the TAC medium access control element (MAC CE). For example, the network device sends a TA value of 10s (absolute value) to the terminal device. If the network device wishes to adjust the TA value to 12s (absolute value), it may indicate to the terminal device that the TA adjustment value is 2s.

In the TA-based PDC method, after receiving the TA value from the network device, the terminal device can pass To approximately determine T _p , that is, the propagation delay, so as to perform PDC based on the determined propagation delay.

In addition, the TA-based PDC method is limited by the TA granularity, such as the bandwidth corresponding to the TA. In addition, the terminal device may fail to apply an accurate TA value due to the failure of the MAC CE to deliver the TAC, resulting in a difference in the TA value applied by the network device and the terminal device, which in turn leads to the accuracy of time synchronization between the network device and the terminal device decline.

5. PDC method based on round-trip-time (RTT)

In the RTT-based PDC method, the network device and the terminal device send reference signals to the opposite end respectively, and the network device measures the time point of receiving the uplink (uplink, UL) reference signal from the terminal device and sends the downlink (downlink, DL) reference signal The difference between the time points, that is, the receiving-sending time difference of the network device; the terminal device measures the difference between the time when it receives the downlink reference signal from the network device and the time when the uplink reference signal is sent, that is, the receiving time of the terminal device - Difference in sending time. Among them, the value of the receiving-sending time difference of the network device can be a positive number or a negative number, depending on the order in which the network device receives the uplink reference signal and sends the downlink reference signal; similarly, the value of the receiving-sending time difference of the terminal device It can be a positive number or a negative number, depending on the order in which the terminal device receives the downlink reference signal and sends the uplink reference signal.

Then, the RTT between the network device and the terminal device is the sum of the receiving-sending time difference of the network device and the receiving-sending time difference of the terminal device, and the propagation delay is

For example, the network device sends the downlink reference signal to the terminal device, and records the sending time _t1 ; the terminal device receives the downlink reference signal, and records the receiving time _t2 ; the terminal device sends the uplink reference signal to the network device, and records the sending time _t3 ; The network device receives the uplink reference signal and records the receiving time t ₄ ; it can be seen that the receiving-sending time difference of the network device is (t ₄ -t ₁ ), and the receiving-sending time difference of the terminal device is (t ₂ -t ₃ ). Then, the RTT between the network device and the terminal device is (t ₄ -t ₁ )+(t ₂ -t ₃ ); the propagation delay is

Wherein, the RTT and the propagation delay may be determined by the terminal equipment, and may also be determined by the network equipment. Referring to Figure 7a, in the process of determining the RTT and propagation delay by the terminal device, the network device needs to send the receiving-sending time difference of the network device to the terminal device after determining the receiving-sending time difference of the network device. The terminal device is based on the network device RTT and Propagation Delay are calculated from the receiving-sending time difference and the determined receiving-sending time difference of the terminal equipment. In conjunction with Figure 7b, in the process of determining the RTT and propagation delay by the network device, the terminal device needs to send the receive-send time difference of the network device to the network device after determining the receive-send time difference of the terminal device. The network device is based on the terminal device The receiving-sending time difference and the determined receiving-sending time difference of the network device calculate the RTT and the propagation delay, and send the determined propagation delay to the terminal device.

In addition, the RTT-based PDC method can meet a more stringent time synchronization accuracy level than the TA-based PDC method. Therefore, the TA-based PDC method is generally used as an alternative to the RTT-based PDC method.

In the embodiment of the present application, the receiving-sending time difference of the terminal device can also be referred to as UE _{receiving end (Receive End, Rx)-transmitting end (Transmit End} , _Tx) ; when the network device is a gNB, the receiving-sending time difference of the network device is also May be called gNB _Rx-Tx .

In the process of time synchronization between the network device and the terminal device, there is still a propagation delay when transmitting wireless frames between the network device and the terminal device, and this propagation delay will affect the time synchronization between the network device and the terminal device , therefore, the network device and the terminal device also need to perform PDC when performing time synchronization.

If the network device performs PDC, it sends the time T after the PDC to the terminal device, that is, the actual time of the determined time reference point is sent to the terminal device; the terminal device receives the time T, but does not know that the time T is determined by the network device The actual time of the time reference point, the terminal device may perform PDC on the time T, which may cause a large difference between the actual time of the time reference point determined by the terminal device and the actual time of the time reference point determined by the network device, and thus lower terminal The accuracy of time synchronization between devices and network devices.

An embodiment of the present application provides a propagation delay compensation method. In the method, the network device determines a first message and sends the first message to the terminal device. The first message is used to indicate whether the network device allows the terminal device to perform PDC on time T. , the time T is a reference time for air interface time synchronization indicated by the network device to the terminal device. Correspondingly, the terminal device receives the first message from the network device, and determines whether it is allowed to perform PDC on the time T according to the first message; when determining that it is allowed to perform the PDC on the time T, it performs the time T according to the configuration of the RTT measurement PDC. The method can realize that the network device controls the terminal device to perform PDC, effectively enhances the degree of cooperation between the terminal device and the network device for time synchronization, thereby avoiding the decrease in the accuracy of time synchronization caused by both the network device and the terminal device performing PDC, and The terminal device can flexibly select the PDC mode for PDC based on the configuration of the RTT measurement, which is conducive to realizing high-precision time synchronization between the network device and the terminal device.

The embodiments of the present application will be further described below in conjunction with the accompanying drawings.

Please refer to FIG. 8 . FIG. 8 is a schematic flowchart of a propagation delay compensation method provided by an embodiment of the present application. The propagation delay compensation method is described from the perspective of interaction between a network device and a terminal device. The propagation delay compensation method includes the following steps:

S101. The network device determines a first message, the first message is used to indicate whether the network device allows the terminal device to perform propagation delay compensation PDC on time T; the time T is a reference for air interface time synchronization indicated by the network device to the terminal device time.

S102. The network device sends the first message to the terminal device. Correspondingly, the terminal device receives the first message.

Wherein, the first message may be carried in an RRC message. The first message may be sent by the network device in a broadcast form or a unicast form. If the network device broadcasts the first message, the first message may be carried by an RRC broadcast message, and the RRC broadcast message may be SIB9; if the network device unicasts the first message, the first message may be carried by an RRC unicast message, and the RRC unicast The message may be a DLInformationTransfer message.

S103. The terminal device determines, according to the first message, whether it is allowed to perform the PDC on the time T.

Wherein, when the first message is used to instruct the network device to allow the terminal device to perform PDC on time T, the terminal device may determine that it is allowed to perform PDC on time T; During the PDC, the terminal device may determine that it is forbidden to perform the PDC for the time T.

In an optional implementation manner, the first message includes a first field; when the network device allows the terminal device to perform PDC on time T, the first field indicates enable (enable); the network device prohibits the terminal device from performing PDC on time T When , the first field indicates disable (disable). Correspondingly, determining whether the terminal device is allowed to perform the PDC on the time T according to the first message may include: the terminal device determines that the terminal device is enabled when the first message includes the first field and the first field indicates enable The device is allowed to perform PDC on time T; the terminal device determines that the terminal device is prohibited from performing PDC on time T when the first message includes the first field and the first field indicates disable (disable). Wherein, the first field may be an optional field in the RRC message.

In addition, in addition to the expression form indicating enable or disable, the first field may also adopt an expression form indicating true or false. Correspondingly, when the first field indicates true, the terminal device determines that the terminal device is allowed to perform PDC on time T; when the first field indicates false, it determines that the terminal device is prohibited from performing PDC on time T. Alternatively, the first field may also be represented by a numerical value. For example, when the value carried by the first field is 1, the terminal device determines that the terminal device is allowed to perform PDC on time T; when the value carried by the first field is 0 , it is determined that the terminal device is prohibited from performing PDC for time T. In this embodiment of the application, there is no limitation on the expression form of the first field.

S104. When determining that the terminal device is allowed to perform the PDC on the time T, perform the PDC on the time T according to the configuration of the round-trip delay RTT measurement.

Wherein, when the terminal device determines that it is allowed to perform the PDC on the time T, it may select a PDC method for performing the PDC from the TA-based PDC method and the RTT-based PDC method based on the following several implementation manners.

Embodiment 1, when the RTT measurement is configured, the terminal device performs PDC on the time T based on the RTT; when the RTT measurement is not configured, the terminal device performs the PDC on the time T based on the TA. It can be seen that in this implementation manner, the terminal device uses whether RTT measurement is configured as a switch for determining the PDC mode, so as to perform PDC on the time T based on the determined PDC mode. In this case, by default, when the RTT measurement is configured on the terminal device, there is always an available RTT measurement result at the terminal device, that is, when the RTT measurement is configured on the terminal device, the PDC is performed on the time T based on the available RTT measurement result. Wherein, the RTT measurement result includes the receiving-sending time difference of the network device and/or the receiving-sending time difference of the terminal device. Then, when the terminal device is configured with RTT measurement, it can calculate the RTT based on the receiving-sending time difference of the terminal device and the receiving-sending time difference of the network device received from the network device, and then perform PDC on the time T based on the RTT to determine the time reference the actual time of the point.

In the embodiment of this application, the terminal device is configured with RTT measurement means that the terminal device has the RTT measurement function, that is, the terminal device has the ability to determine the receiving-sending time difference of the terminal device, the receiving-sending time difference of the receiving network device, and the receiving-sending time difference based on the terminal device. The time difference and the receive-transmit time difference of network devices determine the propagation delay capability.

Embodiment 2: When RTT measurement is configured and there is an available RTT measurement result, the terminal device performs PDC on time T based on the RTT measurement result; when RTT measurement is configured and there is no available RTT measurement result, determine the time T No PDC is performed, or, when a usable RTT measurement result is received, the PDC is performed on the time T based on the RTT measurement result; when the RTT measurement is not configured, the PDC is performed on the time T based on the TA. It can be seen that in this embodiment, the terminal device uses whether RTT measurement is configured and whether there is a usable RTT measurement result as a switch to determine the PDC mode. Compared with Embodiment 1, it is fully considered that the terminal device is configured with RTT measurement and does not exist The circumstances in which the RTT measurement results can be used further specify the behavior of the end device in this situation.

Embodiment 3, when RTT measurement is configured and the existing RTT measurement result is within the validity period, the terminal device performs PDC on the time T based on the RTT measurement result; when RTT measurement is configured and the existing RTT measurement result is not within the validity period, determine the time T No PDC is performed at time T, or, when the RTT measurement result is received within the preset duration, PDC is performed on time T based on the received RTT measurement result; when RTT measurement is not configured, PDC is performed on time T based on TA.

That is to say, when the terminal device is configured with RTT measurement and the existing RTT measurement result is not within the validity period, if the next RTT measurement result arrives at the terminal device within the acceptable time range (that is, the preset duration) of the terminal device, the terminal device The device may perform PDC on the time T based on the next received RTT measurement result; if the time for the next RTT measurement result to reach the terminal device exceeds the acceptable time range of the terminal device, the terminal device may not perform PDC on the time T.

It can be seen that in Embodiment 3, the terminal device uses whether RTT measurement is configured and whether the existing RTT measurement result is within the validity period as a switch to determine the PDC mode. Compared with Embodiment 1, it is fully considered that the terminal device is configured with RTT measurement and exists The situation where the RTT measurement result is not within the validity period further clarifies the behavior of the terminal device in this situation. When the network device periodically sends the RTT measurement result (including the receiving-sending time difference of the network device) to the terminal device configured with RTT, the RTT measurement result received by the terminal device from the network device when performing PDC based on RTT has exceeded the validity period In this case, Embodiment 3 can prevent the terminal device from using the RTT measurement result beyond the valid period to perform PDC on the time T and affect the accuracy of time synchronization between the network device and the terminal device.

Optionally, the preset duration may be manually configured, or determined through negotiation between the network device and the terminal device. The embodiment of the present application does not limit the manner of determining the preset duration.

Optionally, whether the RTT measurement result is within the validity period may be determined by the terminal device through a timer (Timer). Specifically, the terminal device determines that the RTT measurement result is within the valid period when the timer is in the running state; and determines that the RTT measurement result is not within the valid period when the timer is in the stopped state. In addition, the stop state of the timer is not only caused by the fact that the RTT measurement result exceeds the validity period, it may also be caused by the fact that the terminal device does not have an available RTT measurement result; in this case, the terminal device can still execute: determine the time T No PDC is performed, or, when an available RTT measurement result is received within a preset time period, PDC is performed on the time T based on the received RTT measurement result. In this embodiment of the present application, the timer may also be called an RTT measurement result validity timer (RTT result validity timer).

Optionally, the propagation delay compensation method may further include: when the terminal device receives the RTT measurement result from the network device (that is, the receiving-sending time difference of the network device), starting a timer so that the timer is in a running state (also may be referred to as an open state); if the timer expires, the terminal device stops the timer so that the timer is in a stopped state (also referred to as an off state); until the terminal device receives the measurement result of the RTT from the network device again, Then restart the timer, so that the timer is in the running state again. For example, referring to FIG. 9 , the period for the network device to send the receiving-sending time difference of the network device is t ₃ -t ₁ , and the valid period is t ₂ -t ₁ . The terminal device receives the receiving-sending time difference #1 of the network device at time _t1 , and starts the timer; the timer exceeds the validity period at time _t2 , and the terminal device stops the timer; until the terminal device receives the time difference #1 of the network device at time _t3 Receive-send time difference #2, start the timer again.

In an optional implementation manner, when the terminal device determines that it is forbidden to perform PDC on the time T, the propagation delay method may further include: when the terminal device is configured with RTT measurement, sending the latest reception of the terminal device to the network device - Difference in sending time. When the terminal device is not configured with RTT measurement, the behavior of the terminal device will not be affected. It can be seen that the terminal device is prohibited from performing PDC on time T and the condition of RTT measurement is configured, which can trigger the terminal device to report the receiving-sending time difference of the terminal device in the UL, so that the network device can perform PDC based on the receiving-sending time difference of the terminal device precompensation.

In an optional implementation manner, the propagation delay compensation method may further include: when the network device does not indicate whether the terminal device is allowed to perform PDC on time T or is prohibited from performing PDC on time T, the first message does not The first field is included (or the first field indicates empty). Correspondingly, when the first message does not include the first field, that is, when the first field is absent (or the first field indicates empty), the terminal device performs PDC according to the preset PDC manner. The preset PDC mode may be a PDC mode configured for the terminal device, or may be an artificially preset PDC mode. That is to say, when the first field does not exist, the terminal device can fall back to the R16 behavior, that is, the terminal device can perform PDC according to its own implementation. For example, the terminal device may perform PDC according to the PDC mode pre-configured for the terminal device by the device manufacturer. In this case, the network device does not perform PDC pre-compensation for the time T, so as to avoid the decrease in accuracy of time synchronization caused by both the terminal device and the network device performing PDC.

It can be seen that the network device can be configured that the first field exists and indicates enable or disable (disable), or the first field does not exist (absent). The terminal device may determine whether to perform PDC based on the first field and whether the terminal device is configured with an RTT test, as shown in FIG. 10a. Alternatively, the terminal device may determine whether to perform PDC based on the first field, whether the terminal device is configured with RTT measurement, and whether there is an available RTT measurement result, as shown in FIG. 10b . Alternatively, the terminal device may determine whether to perform PDC based on the first field, whether the terminal device is configured with RTT measurement, and whether the existing RTT measurement result is within the validity period, as shown in FIG. 10c.

In another optional implementation manner, the first message may include a first indication, where the first indication is used to indicate whether the network device allows the terminal device to perform the PDC on the time T. Correspondingly, determining whether the terminal device is allowed to perform PDC on time T according to the first message may include: the terminal device determines that the terminal device is allowed to perform PDC on time T when the first indication is used to instruct the network device to allow the terminal device to perform PDC on time T Perform PDC at time T; the terminal device determines that the terminal device is prohibited from performing PDC at time T when the first indication indicates that the network device does not allow the terminal device to perform PDC at time T. In this embodiment, the terminal device may determine whether to perform PDC on time T based on the first indication, and then determine whether to perform PDC on time T, which effectively enhances the degree of cooperation between the terminal device and the network device for time synchronization.

Optionally, the first indication may use a numerical value to indicate whether the network device allows the terminal device to perform PDC on the time T. For example, when the first indication corresponds to a value of 0, it indicates that the terminal device is not allowed to perform PDC on time T, that is, the terminal device is prohibited from performing PDC on time T; when the first indication corresponds to a value of 1, it indicates that the terminal device is allowed to perform PDC on time T. That is, the terminal device is allowed to perform PDC for time T. Alternatively, the first indication may be "correct (true)" to indicate that the terminal device is allowed to perform PDC on time T, and "wrong (false)" to indicate that the terminal device is not allowed to perform PDC on time T. In this embodiment of the present application, there is no limitation on the expression form of the first indication indicating whether the network device allows the terminal device to perform PDC on the time T.

In an optional implementation manner, the first message further includes a second indication, where the second indication is used to indicate whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode. Correspondingly, when the terminal device determines that it is allowed to perform the PDC on the time T, the propagation delay compensation method may further include: performing the PDC on the time T by the terminal device according to the PDC manner indicated by the second indication. Optionally, the second indication may use a numerical value to indicate whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode. For example, when the second indication corresponds to a value of 0, it indicates that the PDC mode is a TA-based PDC mode; when the second indication corresponds to a value of 1, it indicates that the PDC mode is an RTT-based PDC mode. In this embodiment of the present application, there is no limitation on the expression form of the second indication indicating whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode. It can be seen that in this embodiment, the network device can provide flexible PDC mode selection for the terminal device, and the terminal device can determine the PDC mode based on the instruction of the network device. In addition, the PDC method indicated by the network device to the terminal device may be determined based on the service's requirement for time synchronization accuracy, so that the PDC method adopted by the terminal device can better meet the service's requirement for time synchronization accuracy.

Optionally, when the first indication in the first message is used to instruct the terminal device not to perform PDC for the time T, the second indication may be set as a default value. That is to say, when the terminal device is prohibited from performing PDC on the time T, it does not need to consider the PDC mode, and the terminal device may no longer perform the PDC operation on the time T according to the PDC mode indicated by the second instruction.

Optionally, in the foregoing implementation manner, the first indication and the second indication may be carried by 1-bit fields respectively. Specifically, the network device may add a 2-bit field to the RRC message, wherein the 1-bit field is used to bear the first indication, and the other 1-bit field is used to bear the second indication. Referring to Figure 11, taking the first indication and the second indication as numerical values as an example, the first indication carried by the 1-bit field can use the value a1 to indicate whether the terminal device is allowed to perform PDC on time T, and the second indication carried by the 1-bit field The indication may use the value a2 to indicate whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode. If the terminal device receives that a1 is equal to 0, it may determine that it is prohibited from performing PDC on time T; if it receives that a1 is equal to 1, it may determine that it is allowed to perform PDC on time T. In addition, when the network device configuration a1 is 0, a2 can be set to 0 by default. If the terminal device receives that a1 is equal to 0, it may no longer consider the value of a2; if it receives that a1 is equal to 1, it determines the PDC mode based on a2. Specifically, if the terminal device receives that a2 is equal to 0, it may determine that the PDC mode is a TA-based PDC mode; if it receives that a2 is equal to 1, it may determine that the PDC mode is an RTT-based PDC mode.

To sum up, in the propagation delay compensation method, the network device determines the first message and sends the first message to the terminal device, the first message is used to indicate whether the network device allows the terminal device to perform PDC for the time T, and the time T is The reference time for air interface time synchronization indicated by the network device to the terminal device. Correspondingly, the terminal device receives the first message from the network device, and determines whether it is allowed to perform PDC on the time T according to the first message; when the terminal device determines that it is allowed to perform the PDC on the time T, it determines the time T according to the configuration of the RTT measurement. Conduct PDC. It can be seen that this method can realize that the network device controls the terminal device to perform PDC, and effectively enhances the degree of cooperation between the terminal device and the network device for time synchronization, thereby avoiding the decrease in the accuracy of time synchronization caused by both the terminal device and the network device performing PDC , which in turn facilitates the realization of high-precision time synchronization between the terminal device and the network device. In addition, the method also clarifies the message format of the first message (such as the first indication, the second indication or the first field) that the network device indicates for the terminal device whether to be allowed to perform PDC, and clarifies that the terminal device can measure Depending on the configuration situation, the PDC mode can be flexibly selected from the TA-based PDC mode and the RTT-based PDC mode for PDC.

In the propagation delay compensation method shown in FIG. 8 , the network device may also be a structure in which DUs and CUs are separated. The propagation delay compensation method when the network device is a structure in which the DU and the CU are separated will be further described below.

In an optional implementation manner, the network device determining the first message may include: the CU sends a second message to the DU, and the second message includes the default format of the first message; a message. The network device sending the first message to the terminal device may include: the DU sending the first message to the terminal device, where the first message is an RRC broadcast message. This implementation manner can be applied to a broadcast scenario, and the DU decides whether to allow the terminal device to perform PDC on the time T.

Optionally, the default format of the first message may include a format corresponding to the first field. Correspondingly, when the DU receives the second message, determining the first message may include: the DU may determine whether the first field indicates whether it is enabled or disabled based on whether the terminal device is allowed to perform PDC on the time T, and according to the determined As a result, the information carried in the first field is modified to determine the first field to be sent to the terminal device. Optionally, the DU may determine that the first field exists and indicate enable or disable, or the first field does not exist. Correspondingly, when the first message includes the first field and the first field indicates that it is enabled, the terminal device determines that it is allowed to perform PDC on the time T; when the first message includes the first field and the first field indicates that it is enabled When it is not enabled, it is determined that the terminal device is prohibited from performing PDC for the time T; when the first field does not exist in the first message, fall back to the behavior of R16. For related descriptions about the first field, refer to related descriptions in the propagation delay compensation method shown in FIG. 8 , which will not be repeated here.

Optionally, the default format of the first message may include a format corresponding to the first indication and/or the second indication. Correspondingly, when the DU receives the second message, determining the first message may include: the DU determines whether the terminal device is allowed to perform PDC on the time T, and modifies the information carried in the first indication according to the determination result to determine the information sent to the terminal device. first instruction. Correspondingly, the terminal device may determine that it is allowed to perform PDC on time T when the first indication is used to instruct the network device to allow the terminal device to perform PDC on time T; When performing the PDC, it is determined that the PDC for the time T is prohibited.

And/or, the DU determines the PDC mode used by the terminal device when allowing the terminal device to perform PDC on time T, and modifies the information carried in the second indication according to the determination result, so as to determine the second indication sent to the terminal device. Then, the terminal device may perform PDC on the time T according to the PDC manner indicated by the second indication. For relevant elaborations about the first indication and the second indication, refer to the relevant elaborations in the propagation delay compensation method shown in FIG. 8 , which will not be repeated here.

Optionally, the propagation delay compensation method may further include: the CU may also send a default reference time to the DU, and the default reference time may be a false or invalid time; the DU determines a reference time to modify the default reference time, and The determined reference time is taken as time T. In addition, the default reference time sent by the CU to the DU and the default format of the first message may be carried in the same signaling, or may also be carried in different signalings. In this embodiment of the present application, the default reference time sent by the CU to the DU and the default format of the first message may also be collectively referred to as a source message. When the RRC broadcast message is SIB9, the source message may be sent from the CU to the DU through the F1 interface.

In another optional implementation manner, the network device determining the first message may include: the DU sends a second message to the CU, where the second message includes the first indication, the second indication, or the first field in the first message. Value; when the CU receives the second message, it determines the first message. The network device sending the first message to the terminal device may include: the CU sending the first message to the terminal device, where the first message is an RRC unicast message. This embodiment can be applied to a unicast scenario. The DU decides whether to allow the terminal device to perform PDC on the time T, and the CU can directly forward the received first indication, second indication or the value of the first field from the DU to the terminal device. For related descriptions about the first indication, the second indication, and the first field, refer to related descriptions in the propagation delay compensation method shown in FIG. 8 , and details are not repeated here.

Optionally, the DU may also send a time T to the CU, where the time T may be the time after the DU performs the PDC pre-compensation, or the time when the DU does not perform the PDC pre-compensation. Wherein, the DU may perform PDC pre-compensation based on the TA PDC method to determine the time T, or, the DU may perform PDC pre-compensation based on the RTT PDC method to determine the time T. In addition, when the DU performs PDC pre-compensation based on the RTT PDC method, it also needs to request the CU to obtain the receiving-sending time difference of the terminal device to determine the time T.

Optionally, the propagation delay compensation method may further include: when the time T is the time after the DU performs PDC pre-compensation, the DU may determine that the first field indicates that it is not enabled. Correspondingly, when the first message includes the first field and the first field indicates that it is not enabled, the terminal device determines that the terminal device is prohibited from performing PDC for the time T. That is to say, the DU has already performed the PDC pre-compensation, so the terminal device does not need to perform the PDC. This embodiment can avoid the decrease of the accuracy of time synchronization caused by both the terminal device and the network device performing the PDC.

In addition, when the time T is the time when the DU does not perform PDC pre-compensation, the DU may determine that the first field indicates whether to enable or disable it. Correspondingly, when the first message includes the first field and the first field indicates that it is enabled, the terminal device determines that the terminal device is allowed to perform PDC on the time T; when the first message includes the first field and the first field indicates When it is not enabled, it is determined that the terminal device is prohibited from performing PDC for time T. That is to say, the DU does not perform PDC pre-compensation, and the terminal device may determine whether to perform PDC on the time T based on the indication of the first field.

Optionally, the propagation delay compensation method may further include: when the time T is a time when no PDC pre-compensation is performed, the DU may determine that the first field exists and indicate enable or disable, or the first field does not exist . Wherein, when the first field in the received first message does not exist, the terminal device falls back to the R16 behavior. For the relevant operations of the terminal device when it is allowed to perform PDC on time T, the related operations when it is prohibited to perform PDC on time T, and the relevant content of R16 behavior, please refer to the relevant information in the propagation delay compensation method shown in Figure 8. elaboration and will not be repeated here.

In addition, the DU can send the time T and the value of the first indication, the second indication or the first field to the CU through the interface F1, and the time T sent by the DU to the CU, and the first indication, the second indication or the value of the first field The values may be carried by the same signaling, or may also be carried by different signaling.

In yet another optional implementation manner, the network device determining the first message may include: the DU sends a second message to the CU, and the second message includes the value of time T and the value of PDC; A value that determines the first message. The network device sending the first message to the terminal device may include: the CU sending the first message to the terminal device, where the first message is an RRC unicast message. This implementation manner can be applied to a unicast scenario, and the CU decides whether to allow the terminal device to perform PDC on the time T. Optionally, the DU may send the value of the time T and the value of the PDC to the CU through the interface F1.

Optionally, the value of the PDC may be determined by the DU through a TA-based PDC manner, or may be determined by the DU through an RTT-based PDC manner. Wherein, when the DU determines the PDC value through the RTT-based PDC method, it also needs to request the CU to obtain the receiving-sending time difference of the terminal device to determine the PDC value. In this embodiment of the present application, the value of the PDC may also be referred to as a pre-compensation value (PDC value).

Optionally, the CU determines the first message according to the value of the time T and the value of the PDC, which may include: if the CU decides to perform PDC pre-compensation, send the sum of the time T and the value of the PDC to the terminal device, and indicate not to use Correspondingly, when the first message includes the first field and the first field indicates that it is not enabled, the terminal device may determine that the terminal device is prohibited from performing PDC for time T.

In addition, if the CU decides not to perform PDC pre-compensation, it discards the value of the PDC, and sends the first field indicating enabling or disabling to the terminal device, or configures that the first field does not exist. Correspondingly, when the first message includes the first field and the first field indicates that it is enabled, the terminal device determines that the terminal device is allowed to perform PDC on the time T; when the first message includes the first field and the first field indicates When it is not enabled, it is determined that the terminal device is prohibited from performing PDC for time T; when the first field does not exist in the first message, fall back to the behavior of R16. It can be seen that when the CU performs PDC pre-compensation, it instructs the terminal device not to perform PDC, which can avoid the decrease of the accuracy of time synchronization caused by both the terminal device and the network device performing PDC. In addition, the DU can send the time T and the value of the PDC to the CU through the interface F1. Regarding the relevant operations when the terminal device is allowed to perform PDC on time T, the relevant operations when it is prohibited to perform PDC on time T, and the relevant content of R16 behavior, please refer to the relevant description in the propagation delay compensation method shown in Figure 8. I won't repeat them here.

In addition, the propagation delay compensation method provided in the embodiment of the present application is not only applicable to a communication scenario between a network device and a terminal device, but also applicable to a sidelink (sidelink, SL) communication scenario as shown in FIG. 12 . The side link communication scenario includes a first terminal device and a second terminal device. Communication between the first terminal device and the second terminal device may be performed through a side link interface, that is, side link transmission (SL transmission).

Wherein, the first terminal device can be used to determine the first message; it can also be used to send the first message to the second terminal device; the first message is used to indicate whether the first terminal device allows the second terminal device to perform PDC on time T, time T is a reference time for air interface time synchronization indicated by the first terminal device to the second terminal device. The second terminal device can be used to receive the first message from the first terminal device; the second terminal device can also be used to determine whether it is allowed to perform PDC on time T according to the first message; the second terminal device can also be used to determine whether it is allowed to When the PDC is performed at the time T, the PDC is performed on the time T according to the configuration of the RTT measurement. In addition, the first terminal device may also perform related operations of the network device in the above method embodiments, and the second terminal device may also perform related operations of the terminal device in the above method embodiments, which will not be repeated here.

FIG. 13 and FIG. 14 are schematic structural diagrams of possible communication devices provided by the embodiments of the present application. These communication apparatuses can realize the functions of the terminal equipment or the network equipment in the above method embodiments, and therefore can also realize the beneficial effects of the above method embodiments. In this embodiment of the application, the communication device may be a network device in the communication system shown in Figure 1a, Figure 1b or Figure 1c, or a terminal device in the communication system, or it may be a device applied to a terminal device or a network A module (such as a chip) of a device.

As shown in FIG. 13 , a communication device 1300 includes a communication unit 1301 and a processing unit 1302 . The communication device 1300 may be used to implement the functions of the network device or the terminal device in the foregoing method embodiments.

When the communication device 1300 is used to realize the function of the terminal device in the above method embodiment: the communication unit 1301 is used to receive the first message from the network device, the first message is used to indicate whether the network device allows the communication device 1300 to adjust the time T Propagation delay compensation PDC is performed; the time T is a reference time for air interface time synchronization indicated by the network device to the communication apparatus 1300 . The processing unit 1302 is configured to determine whether to perform PDC on time T according to the first message; the processing unit 1302 is also configured to determine whether to perform PDC on time T according to the configuration of the round-trip delay RTT measurement. Conduct PDC.

In an optional implementation manner, the processing unit 1302 determines whether the time T is allowed to perform PDC according to the first message, specifically: when the first message includes the first field and the first field indicates enable When enabled, it is determined that the communication device 1300 is allowed to perform PDC for time T; Optionally, the processing unit 1302 is further configured to perform PDC according to a preset PDC manner when the first message does not include the first field.

In an optional implementation manner, when the processing unit 1302 determines that the communication device 1300 is allowed to perform the PDC on the time T, it performs the PDC on the time T according to the configuration of the RTT measurement, specifically: when the RTT measurement is configured, based on RTT performs PDC on time T; when RTT measurement is not configured, PDC is performed on time T based on timing advance TA.

In an optional implementation manner, when the processing unit 1302 determines that the communication device 1300 is allowed to perform the PDC on the time T, perform the PDC on the time T according to the configuration of the RTT measurement, specifically for:

When RTT measurement is configured and there is an available RTT measurement result, perform PDC on time T based on the RTT measurement result;

When RTT measurement is configured and there is no available RTT measurement result, determine not to perform PDC for time T, or, when receiving available RTT measurement result, perform PDC for time T based on the RTT measurement result;

When RTT measurement is not configured, the time T is PDC based on the timing advance TA.

In an optional implementation manner, when the processing unit 1302 determines that the communication device 1300 is allowed to perform the PDC on the time T, it performs the PDC on the time T according to the configuration of the round-trip delay RTT measurement, specifically for:

When RTT measurement is configured and the existing RTT measurement result is within the validity period, PDC is performed on time T based on the RTT measurement result;

When RTT measurement is configured and the existing RTT measurement result is not within the validity period, it is determined not to perform PDC for time T, or, when the RTT measurement result is received within the preset duration, PDC is performed for time T based on the received RTT measurement result ;

When RTT measurement is not configured, the time T is PDC based on the timing advance TA.

In an optional implementation manner, whether the RTT measurement result is within the validity period is determined by the processing unit through a timer.

In an optional implementation manner, when the processing unit 1302 determines that the communication device 1300 is prohibited from performing PDC on the time T, it is also used to: send the latest reception-send of the communication device 1300 to the network device when RTT measurement is configured Time difference.

When the communication device 1300 is used to realize the function of the network device in the above method embodiment: the processing unit 1302 is used to determine the first message, the first message is used to indicate whether the network device allows the terminal device to perform propagation delay compensation for the time T PDC; the time T is a reference time for air interface time synchronization indicated by the communication device to the terminal device; the communication unit 1301 is configured to send a first message to the terminal device.

In an optional implementation manner, the first message includes a first field; when the communication device 1300 allows the terminal device to perform PDC on time T, the first field indicates enable; the communication device 1300 prohibits the terminal device from performing PDC on time T When , the first field indicates that disable is not enabled; the second indication is used by the terminal device to determine the PDC mode. Optionally, when the communication apparatus 1300 does not indicate whether the terminal device is allowed to perform the PDC on the time T or is prohibited from performing the PDC on the time T, the first message does not include the first field.

In an optional implementation manner, the communication device 1300 is a structure in which the distributed unit DU and the centralized unit CU are separated,

The processing unit 1302 determines the first message, which is specifically used to: send a second message to the DU through the CU, the second message includes a default format of the first message; when the DU receives the second message, determine the first message;

The communication unit 1301 sends the first message to the terminal device, and is specifically configured to: send the first message to the terminal device through the DU, where the first line message is a radio resource control RRC broadcast message.

In an optional implementation manner, the communication device 1300 is a structure in which the distributed unit DU and the centralized unit CU are separated,

The processing unit 1302 determines the first message, and is specifically configured to: send a second message to the CU through the DU, where the second message includes the value of the first field in the first message; when the CU receives the second message, determine the first message;

The communication unit 1301 sends the first message to the terminal device, and is specifically configured to: send the first message to the terminal device through the CU, where the first message is an RRC unicast message.

In an optional implementation manner, the communication device 1300 is a structure in which the distributed unit DU and the centralized unit CU are separated,

The processing unit 1302 determines the first message, which is specifically used to: send a second message to the CU through the DU, the second message includes the value of the time T and the value of the PDC; the CU determines the first message according to the value of the time T and the value of the PDC;

The communication unit 1301 sends the first message to the terminal device, and is specifically configured to: send the first message to the terminal device through the CU, where the first message is an RRC unicast message.

For a more detailed description of the foregoing communication apparatus 1300, reference may be made to relevant descriptions in the foregoing method embodiments, and details are not repeated here.

As shown in Figure 14, the communication device 1400 may be a terminal device or a network device, or a chip, a chip system, or a processor that supports the terminal device to implement the above method, or a chip or chip that supports the network device to implement the above method. system, or processor, etc. The device can be used to implement the methods described in the above method embodiments, and for details, refer to the descriptions in the above method embodiments.

The communication device 1400 may include one or more processors 1401 . The processor 1401 may be a general-purpose processor or a special-purpose processor. For example, it may be a baseband processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or a central processing unit (Central Processing Unit, CPU). The baseband processor can be used to process communication protocols and communication data, and the central processing unit can be used to control communication devices (such as base stations, baseband chips, terminals, terminal chips, DU or CU, etc.), execute software programs, and process Data for Software Programs.

Optionally, the communication device 1400 may include one or more memories 1402, on which instructions 1404 may be stored, and the instructions may be executed on the processor 1401, so that the communication device 1400 executes the above method Methods described in the Examples. Optionally, data may also be stored in the memory 1402 . The processor 1401 and the memory 1402 can be set separately or integrated together.

The memory 1402 may include but not limited to non-volatile memory such as hard disk drive (HDD) or solid-state drive (solid-state drive, SSD), random access memory (Random Access Memory, RAM), erasable and programmable Read-only memory (Erasable Programmable ROM, EPROM), ROM or portable read-only memory (Compact Disc Read-Only Memory, CD-ROM), etc.

Optionally, the communication device 1400 may further include a transceiver 1405 and an antenna 1406 . The transceiver 1405 may be called a transceiver unit, a transceiver, or a transceiver circuit, etc., and is used to realize a transceiver function. The transceiver 1405 may include a receiver and a transmitter, and the receiver may be called a receiver or a receiving circuit for realizing a receiving function; the transmitter may be called a transmitter or a sending circuit for realizing a sending function.

The communication apparatus 1400 is a terminal device: the transceiver 1405 is configured to execute S102 in the propagation delay compensation method shown in FIG. 8 . The processor 1401 is used in S103 and S104 in the propagation delay compensation method shown in FIG. 8 .

The communication device 1400 is a network device: the transceiver 1405 is configured to execute S102 in the propagation delay compensation method shown in FIG. 8 . The processor 1401 is configured to execute S101 in the propagation delay compensation method shown in FIG. 8 .

In another possible design, the processor 1401 may include a transceiver for implementing receiving and sending functions. For example, the transceiver may be a transceiver circuit, or an interface, or an interface circuit. The transceiver circuits, interfaces or interface circuits for realizing the functions of receiving and sending can be separated or integrated together. The above-mentioned transceiver circuit, interface or interface circuit may be used for reading and writing code/data, or the above-mentioned transceiver circuit, interface or interface circuit may be used for signal transmission or transmission.

In yet another possible design, optionally, the processor 1401 may store instructions 1403, and the instructions 1403 run on the processor 1401, and may cause the communication device 1400 to execute the methods described in the foregoing method embodiments. The instruction 1403 may be fixed in the processor 1401, in this case, the processor 1401 may be implemented by hardware.

In yet another possible design, the communication device 1400 may include a circuit, and the circuit may implement the function of sending or receiving or communicating in the foregoing method embodiments. The processor and the transceiver described in the embodiments of the present application may be implemented in an integrated circuit (integrated circuit, IC), an analog IC, a radio frequency integrated circuit (radio frequency integrated circuit, RFIC), a mixed signal IC, or an application specific integrated circuit (application specific integrated circuit, ASIC), printed circuit board (printed circuit board, PCB), electronic equipment, etc. The processor and transceiver can also be fabricated using various IC process technologies such as complementary metal oxide semiconductor (CMOS), nMetal-oxide-semiconductor (NMOS), p-metal Oxide semiconductor (positive channel metal oxide semiconductor, PMOS), bipolar junction transistor (Bipolar Junction Transistor, BJT), bipolar CMOS (BiCMOS), silicon germanium (SiGe), gallium arsenide (GaAs), etc.

The communication device described in the above embodiments may be terminal equipment, network equipment or access network equipment, but the scope of the communication device described in the embodiments of this application is not limited thereto, and the structure of the communication device may not be limited by Figure 14 . A communication device may be a stand-alone device or may be part of a larger device. For example the communication device may be:

(1) Stand-alone integrated circuits ICs, or chips, or chip systems or subsystems;

(2) A set of one or more ICs, optionally, the set of ICs may also include storage components for storing data and instructions;

(3) ASIC, such as a modem (modulator);

(4) Modules that can be embedded in other devices;

(5) Receivers, terminals, smart terminals, cellular phones, wireless devices, handsets, mobile units, vehicle-mounted devices, network devices, cloud devices, artificial intelligence devices, etc.;

(6) Others and so on.

For the case where the communication device may be a chip or a chip system, refer to the schematic structural diagram of the chip shown in FIG. 15 . The chip 1500 shown in FIG. 15 includes a processor 1501 and an interface 1502 . Wherein, the number of processors 1501 may be one or more, and the number of interfaces 1502 may be more than one. The processor 1501 may be a logic circuit, and the interface 1502 may be an input-output interface, an input interface, or an output interface. The chip 1500 may also include a memory 1503 .

In one design, for the case where the chip is used to implement the functions of the terminal device in the embodiment of the present application: the interface 1502 is used to receive a first message from the network device, and the first message is used to indicate whether the network device allows the chip 1500 to Propagation delay compensation PDC is performed at time T; the time T is the reference time for air interface time synchronization indicated by the network device to the chip 1500; the processor 1501 is used to determine whether to perform PDC on time T according to the first message The processor 1501 is further configured to perform PDC on time T according to the configuration of round-trip delay RTT measurement when determining that PDC is allowed on time T.

In another design, for the case where the chip is used to implement the functions of the network device in the embodiment of the present application: the processor 1501 is configured to determine the first message, and the first message is used to indicate whether the chip 1500 allows the terminal device to check the time T Propagation delay compensation PDC is performed; the time T is a reference time for air interface time synchronization indicated by the chip 1500 to the terminal device. Interface 1502, configured to send the first message to the terminal device.

In the embodiment of the present application, the communication device 1400 and the chip 1500 may also execute the implementation described in the communication device 1300 above. Those skilled in the art can also understand that various illustrative logical blocks and steps listed in the embodiments of the present application can be implemented by electronic hardware, computer software, or a combination of both. Whether such functions are implemented by hardware or software depends on the specific application and overall system design requirements. Those skilled in the art may use various methods to implement the described functions for each specific application, but such implementation should not be understood as exceeding the protection scope of the embodiments of the present application.

The embodiment of the present application and the above-mentioned method embodiment are based on the same idea, and the technical effects brought about by it are also the same. For specific principles, please refer to the description of the above-mentioned method embodiment, which will not be repeated here.

The present application also provides a computer-readable storage medium for storing computer software instructions, and when the instructions are executed by a communication device, the functions of any one of the above method embodiments are realized.

The present application also provides a computer program product, which is used for storing computer software instructions, and when the instructions are executed by a communication device, the functions of any one of the above method embodiments are realized.

The present application also provides a computer program, which, when running on a computer, can realize the functions of any one of the above method embodiments.

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

In each embodiment of the present application, if there is no special explanation and logical conflict, the terms and/or descriptions between different embodiments are consistent and can be referred to each other, and the technical features in different embodiments are based on their inherent Logical relationships can be combined to form new embodiments.

In this application, "at least one" means one or more, and "multiple" means two or more. "And/or" describes the association relationship of associated objects, indicating that there can be three types of relationships, for example, A and/or B, which can mean: A exists alone, A and B exist at the same time, and B exists alone, where A, B can be singular or plural. In the text description of this application, the character "/" generally indicates that the contextual objects are an "or" relationship.

It can be understood that the various numbers involved in the embodiments of the present application are only for convenience of description, and are not used to limit the scope of the embodiments of the present application. The size of the serial numbers of the above-mentioned processes does not mean the order of execution, and the execution order of each process should be determined by its functions and internal logic.

Claims (19)

1. A propagation delay compensation method, the method comprising:

The method comprises the steps that a terminal device receives a first message from a network device, wherein the first message is used for indicating whether the network device allows the terminal device to carry out propagation delay compensation PDC on time T; the time T is a reference time for air interface time synchronization indicated by the network equipment to the terminal equipment;

the terminal equipment determines whether PDC is allowed to be carried out on the time T or not according to the first message;

and when the terminal equipment determines that the PDC is allowed to be carried out on the time T, carrying out PDC on the time T according to the configuration condition of Round Trip Time (RTT) measurement.

2. The method according to claim 1, wherein the terminal device determining whether PDC for the time T is allowed or not based on the first message comprises:

the terminal equipment determines that the terminal equipment is allowed to carry out PDC on the time T when the first message comprises a first field and the first field indicates that enabling is carried out;

and when the first message comprises the first field and the first field indicates that disable is not enabled, the terminal equipment determines that the terminal equipment is forbidden to carry out PDC on the time T.

3. The method according to claim 2, wherein the method further comprises:

and the terminal equipment performs PDC according to a preset PDC mode when the first field is not included in the first message.

4. A method according to any of claims 1 to 3, characterized in that when the terminal device determines that PDC is allowed for the time T, PDC is performed for the time T according to the configuration of RTT measurements, comprising:

when the terminal equipment is configured with the RTT measurement, PDC is carried out on the time T based on the RTT;

and when the RTT measurement is not configured, the terminal equipment performs PDC on the time T based on a timing advance TA.

5. A method according to any of claims 1 to 3, characterized in that when the terminal device determines that PDC is allowed for the time T, PDC is performed for the time T according to the configuration of RTT measurements, comprising:

the terminal equipment carries out PDC on the time T based on the RTT measurement result when the RTT measurement is configured and a usable RTT measurement result exists;

the terminal equipment determines that PDC is not carried out on the time T when the RTT measurement is configured and no usable RTT measurement result exists, or carries out PDC on the time T based on the RTT measurement result when the usable RTT measurement result is received;

And when the RTT measurement is not configured, the terminal equipment performs PDC on the time T based on a timing advance TA.

6. A method according to any of claims 1 to 3, characterized in that when the terminal device determines that PDC is allowed for the time T, PDC is performed for the time T according to the configuration of RTT measurements, comprising:

the terminal equipment carries out PDC on the time T based on the RTT measurement result when the RTT measurement is configured and the existing RTT measurement result is in the effective period;

when the RTT measurement is configured and the existing RTT measurement result is not in the effective period, the terminal equipment determines that PDC is not carried out on the time T, or receives the RTT measurement result in a preset time period, and carries out PDC on the time T based on the received RTT measurement result;

and when the RTT measurement is not configured, the terminal equipment performs PDC on the time T based on a timing advance TA.

7. The method of claim 6, wherein the RTT measurement is determined by the terminal device through a timer during a period of validity.

8. The method according to any of the claims 1 to 7, characterized in that when the terminal device determines that PDC of the time T is prohibited, the method further comprises:

And the terminal equipment sends the latest receiving-sending time difference of the terminal equipment to the network equipment when the RTT measurement is configured.

9. A propagation delay compensation method, the method comprising:

the network equipment determines a first message, wherein the first message is used for indicating whether the network equipment allows the terminal equipment to carry out propagation delay compensation PDC on time T; the time T is a reference time for air interface time synchronization indicated by the network equipment to the terminal equipment;

the network device sends the first message to the terminal device.

10. The method of claim 9, wherein the first message comprises a first field; when the network device allows the terminal device to perform PDC on the time T, the first field indicates enable; and when the network equipment prohibits the terminal equipment from PDC to the time T, the first field indicates that disable is not enabled.

11. The method of claim 10, wherein the first field is not included in the first message when the network device does not indicate whether the terminal device is allowed to PDC the time T or is prohibited from PDC the time T.

12. The method according to any one of claims 9 to 11, wherein the network device is a separate architecture of a distributed unit DU and a centralized unit CU,

the network device determines a first message comprising:

the CU sends a second message to the DU, the second message including a default format of the first message;

when the DU receives the second message, determining the first message;

the network device sending the first message to the terminal device, including:

the DU sends the first message to the terminal device, the first line message being a radio resource control, RRC, broadcast message.

13. The method according to any one of claims 9 to 11, wherein the network device is a separate architecture of a distributed unit DU and a centralized unit CU,

the network device determines a first message comprising:

the DU sends a second message to the CU, wherein the second message comprises a value of a first field in the first message;

when the CU receives the second message, determining the first message;

the network device sending the first message to the terminal device, including:

the CU sends the first message to the terminal device, wherein the first message is a Radio Resource Control (RRC) unicast message.

14. The method according to any one of claims 9 to 11, wherein the network device is a separate architecture of a distributed unit DU and a centralized unit CU,

the network device determines a first message comprising:

the DU sends a second message to the CU, wherein the second message comprises the value of the time T and the value of the PDC;

the CU determines the first message according to the value of the time T and the value of the PDC;

the network device sending the first message to the terminal device, including:

the CU sends the first message to the terminal device, wherein the first message is a Radio Resource Control (RRC) unicast message.

15. A communication device, the device comprising:

a communication unit, configured to receive a first message from a network device, where the first message is configured to indicate whether the network device allows the communication apparatus to perform propagation delay compensation PDC for time T; the time T is a reference time for air interface time synchronization indicated by the network equipment to the communication device;

a processing unit, configured to determine whether PDC is allowed to be performed on the time T according to the first message;

And the processing unit is further used for performing PDC on the time T according to the configuration condition of RTT measurement when the PDC is allowed to be performed on the time T.

16. A communication device, the device comprising:

a processing unit, configured to determine a first message, where the first message is used to instruct the communication apparatus whether to allow the terminal device to perform propagation delay compensation PDC on time T; the time T is a reference time for air interface time synchronization indicated to the terminal equipment by the communication device;

and the communication unit is used for sending the first message to the terminal equipment.

17. A communication device comprising a memory and a processor;

the memory is used for storing instructions or computer programs;

the processor being configured to execute the computer program or instructions stored in the memory to cause the communication device to perform the method of any one of claims 1 to 8 or to perform the method of any one of claims 9 to 14.

18. A computer readable storage medium storing a computer program which, when run on a computer, causes the computer to perform the method of any one of claims 1 to 8 or to perform the method of any one of claims 9 to 14.

19. A computer program product comprising computer instructions which, when run on a computer, cause the computer to perform the method of any one of claims 1 to 8 or to perform the method of any one of claims 9 to 14.