CN116456444A

CN116456444A - Propagation delay compensation method and device

Info

Publication number: CN116456444A
Application number: CN202210012218.3A
Authority: CN
Inventors: 唐小伟; 范强; 徐小英
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-01-06
Filing date: 2022-01-06
Publication date: 2023-07-18

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 disclosure relates to the field of communications technologies, and in particular, to a propagation delay compensation method and apparatus.

Background

In a time delay sensitive network (time sensitive network, TSN), to support time-based operation control, it is desirable to maintain time synchronization between TSN devices. In the third generation partnership project (3rd generation partnership project,3GPP) Rel-16, a scheme is proposed in which the 5G system (5 GS) supports TSN, i.e. 5GS is the TSN bridging device. Specifically, the 5GS receives the message from the TSN device through the user plane function (User Plane Function, UPF) network element, and forwards the message to the other TSN device through the terminal device.

When the TSN network uses the high-precision time synchronization protocol (precision time protocol, PTP) to ensure high-precision time synchronization, the 5GS may be used as a transparent clock in PTP, and the residence time of the PTP message in the 5GS, that is, the time difference between the time when the UPF receives the PTP message from the TSN device and the time when the terminal device sends the PTP message to other TSN devices, needs to be calculated. It can be seen that time synchronization needs to be maintained between the UPF and the terminal device. The time synchronization between the terminal device and the UPF may be guaranteed by both retrieving time from the same clock source. In particular, the terminal device and the UPF may each maintain time synchronization with the network device, thereby achieving time synchronization between the terminal device and the UPF. Wherein, the UPF and the network equipment can realize time synchronization based on PTP. How to achieve time synchronization between a terminal device and a network device is a problem to be solved.

Disclosure of Invention

The embodiment of the application provides a propagation delay compensation method and a propagation delay compensation device, which are beneficial to realizing time synchronization between terminal equipment and network equipment.

In a first aspect, the present application provides a propagation delay compensation method, the method comprising: the terminal device receiving a first message from the network device, the first message being for indicating whether the network device allows the terminal device to perform propagation delay compensation (propagation delay compensation, PDC) for the 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; when the terminal device determines that the PDC is allowed to be performed on the time T, the PDC is performed on the time T according to the configuration condition of round-trip-time (RTT) measurement.

Therefore, the terminal equipment can determine whether the PDC is allowed to be carried out on the time T or not based on the indication of the network equipment, the coordination degree of time synchronization between the terminal equipment and the network equipment is effectively enhanced, the reduction of accuracy of the time synchronization caused by PDC carried out by the terminal equipment and the network equipment can be avoided, the PDC mode can be flexibly selected by the terminal equipment based on the configuration condition according to RTT measurement, and the high-precision time synchronization between the terminal equipment and the network equipment is facilitated.

In an alternative embodiment, the terminal device determines whether to allow PDC to be performed on time T according to the first message, including: when the first message comprises a first field and the first field indicates enable (enable), the terminal equipment determines that the terminal equipment is allowed to carry out PDC on time T; the terminal device determines that the terminal device is barred from PDC for time T when the first message includes a first field and the first field indicates disable. In this embodiment, the terminal device may determine whether to allow PDC to be performed on the time T based on the indication of the first field, which effectively enhances the coordination degree of time synchronization between the terminal device and the network device.

Optionally, the method may further include: and when the terminal equipment does not comprise the first field in the first message, PDC is carried out according to a preset PDC mode.

In an alternative embodiment, when the terminal device determines that the PDC is allowed to be performed on the time T, performing the PDC on the time T according to the configuration condition of RTT measurement includes: when terminal equipment is configured with Round Trip Time (RTT) measurement, PDC is carried out on time T based on RTT; and when the RTT measurement is not configured, the terminal equipment performs PDC on the time T based on Timing Advance (TA). It can be seen that this embodiment specifies the relevant behavior when the terminal device is allowed to PDC the time T. And the PDC mode determined by the RTT measurement is configured by the terminal equipment, so that the requirement of the actual condition of the terminal equipment on the PDC can be met, and the time synchronization precision between the terminal equipment and the network equipment can be further improved effectively.

In an alternative embodiment, when the terminal device determines that the PDC is allowed to be performed on the time T, performing the PDC on the time T according to the configuration condition of RTT measurement includes: when the terminal equipment is configured with Round Trip Time (RTT) measurement and has available Round Trip Time (RTT) measurement results, PDC is carried out on the time T based on the RTT measurement results; when the terminal equipment configures Round Trip Time (RTT) measurement and no usable Round Trip Time (RTT) measurement result exists, determining that PDC is not carried out on the time T, or when the usable RTT measurement result is received, carrying out PDC on the time T based on the RTT measurement result; and when the RTT measurement is not configured, the terminal equipment performs PDC on the time T based on the timing advance TA.

It can be seen that this embodiment specifies the relevant behavior when the terminal device is allowed to PDC the time T. In addition, the terminal device uses whether the RTT measurement is configured and whether the usable RTT measurement result exists as a switch for determining the PDC method, and compared with a method for determining the PDC method based on whether the RTT measurement is configured, the terminal device fully considers the situation that the terminal device is configured with the RTT measurement and the usable RTT measurement result does not exist, and the time synchronization precision between the terminal device and the network device can be effectively improved.

In an alternative embodiment, when the terminal device determines that the PDC is allowed to be performed on the time T, performing the PDC on the time T according to the configuration condition of RTT measurement includes: when the terminal equipment is configured with Round Trip Time (RTT) measurement and the existing RTT measurement result is within the valid period, PDC is carried out on the time T based on the RTT measurement result; when the terminal equipment configures Round Trip Time (RTT) measurement and the existing RTT measurement result is not in the effective period, determining that PDC is not carried out on the time T, or when the RTT measurement result is received in the preset time length, carrying 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 the timing advance TA.

It can be seen that this embodiment specifies the relevant behavior when the terminal device is allowed to PDC the time T. And, the terminal device takes whether the RTT measurement is configured and whether the existing RTT measurement result is within the validity period as a switch for determining the PDC mode, and compared with the mode of determining the PDC mode only based on whether the RTT measurement is configured, the terminal device fully considers the situation that the terminal device is configured with the RTT measurement and the existing RTT measurement result exceeds the validity period, and the time synchronization precision between the terminal device and the network device can be effectively improved.

In an alternative embodiment, whether the RTT measurement is within the validity period is determined by the terminal device through a timer.

In an alternative embodiment, when the terminal device determines that PDC is prohibited for time T, the method further includes: and when the terminal equipment is configured with the Round Trip Time (RTT) measurement, the latest receiving-transmitting time difference of the terminal equipment is transmitted to the network equipment. This embodiment is advantageous in that the network device can perform PDC based on the latest reception-transmission time difference of the terminal device.

In a second aspect, the present application provides 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; time T is a reference time indicated by the network device to the terminal device for air time synchronization: the network device sends a first message to the terminal device.

Therefore, the network device can indicate whether the terminal device is allowed to perform PDC on the time T or not, so that the terminal device can perform PDC on the time T based on the indication of the network device, the network device can control the terminal device to perform PDC, the matching degree of time synchronization between the terminal device and the network device is effectively enhanced, the accuracy reduction of time synchronization caused by PDC both the network device and the terminal device can be avoided, and further high-precision time synchronization between the network device and the terminal device is facilitated.

In an alternative embodiment, the first message includes a first field; when the network equipment allows the terminal equipment to carry out PDC on the time T, the first field indicates enabling; when the network equipment prohibits the terminal equipment from PDC to the 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, 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, and the first field is not included in the first message.

In an alternative embodiment, the network device is a architecture in which a Distributed Unit (DU) is separated from a Centralized Unit (CU), and determining the first message includes: 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, it determines the first message. The network device sends a first message to the terminal device, including: the DU sends a first message to the terminal device, the first line message being a radio resource control (radio resource control, RRC) broadcast message. It can be seen that this embodiment can be applied in a broadcast scenario, where the DU decides whether the terminal device is allowed to PDC the time T, i.e. whether the terminal device is allowed to PDC the time T.

In an alternative embodiment, the network device determines the first message for a framework in which the DU is separate from the CU, including: the DU sends a second message to the CU, the second message including the value of the first field in the first message; when the CU receives the second message, the CU determines the first message. The network device sends a first message to the terminal device, including: the CU sends a first message to the terminal device, the first message being a radio resource control, RRC, unicast message. It can be seen that this embodiment can be applied in a unicast scenario, where the DU decides whether the terminal device is allowed to PDC the time T, i.e. whether the terminal device is allowed to PDC the time T.

In an alternative embodiment, the network device determines the first message for an architecture in which the distributed unit DU is separate from the centralized unit CU, comprising: the DU sends a second message to the CU, the second message comprising the value of time T and the value of PDC; the CU determines the first message from the value of time T and the value of PDC. The network device sends a first message to the terminal device, including: the CU sends a first message to the terminal device, the first message being a radio resource control, RRC, unicast message. It can be seen that this embodiment can be applied in unicast scenarios, where the CU decides whether to allow the terminal device to PDC the time T, i.e. whether to allow the terminal device to PDC the time T.

In a third aspect, the present application provides a communication device, and the beneficial effects may be referred to the description of the first aspect and are not repeated herein. The communication device has the functionality to implement the actions in the method example of the first aspect described above. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

In one possible design, the terminal device includes: a communication unit for receiving a first message from a network device, the first message being for indicating whether the network device allows the communication apparatus to perform propagation delay compensation PDC for time T; time T is a reference time indicated by the network device to the communication apparatus for air interface time synchronization; a processing unit, configured to determine whether PDC is allowed to be performed on time T according to the first message; and the processing unit is also used for carrying out PDC on the time T according to the configuration condition of RTT measurement when the PDC on the time T is determined to be allowed.

These modules may perform the corresponding functions in the method examples of the first aspect, which are specifically referred to in the detailed description of the method examples and are not described herein.

In a fourth aspect, the present application provides a communication device, and the beneficial effects may be referred to the description of the second aspect and are not repeated here. The communication device has the functionality to implement the behavior in the method example of the second aspect described above. The functions may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the functions described above.

In one possible design, the communication device includes: 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.

These modules may perform the corresponding functions in the method examples of the second aspect, which are specifically referred to in the method examples and are not described herein.

In a fifth aspect, the present application provides a communication device comprising a memory and a processor. Wherein the memory is for storing instructions or computer programs; the processor is configured to execute a computer program or instructions stored in the memory to cause the communication device to perform the method according to the first aspect or to perform the method according to the second aspect.

In a sixth aspect, the present application provides a computer readable storage medium storing a computer program for causing a computer to perform the method of the first aspect or the second aspect when the computer program is run on the computer.

In a seventh aspect, embodiments of the present application provide a chip or chip system, the chip or chip system including at least one processor and an interface, the interface and the at least one processor being interconnected by a line, the at least one processor being configured to execute a computer program or instructions to perform a method according to the first aspect, or to perform a method according to the second aspect.

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

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

In one possible implementation, the chip or chip system described above in the present application further includes at least one memory, where the at least one memory has instructions stored therein. The memory may be a memory unit within the chip, such as a register, a cache, etc., or may be a memory unit of the chip (e.g., a read-only memory, a random access memory, etc.).

In an eighth aspect, the present application provides a computer program or computer program product comprising computer instructions which, when run on a computer, cause the computer to perform the method of the first aspect, or to perform the method of the second aspect.

Drawings

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

FIG. 1b is a schematic diagram of a system architecture according to an embodiment of the present disclosure;

FIG. 1c is a schematic diagram of another system architecture according to an embodiment of the present disclosure;

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

fig. 3 is a schematic diagram of a bridging device with 5GS as a TSN according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a transparent clock with 5GS according to an embodiment of the present application;

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

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

FIG. 7a is a schematic diagram of an RTT-based PDC scheme provided in an embodiment of the present application;

FIG. 7b is a schematic diagram of another PDC approach based on RTT provided by embodiments of the present application;

Fig. 8 is a flow chart of a propagation delay compensation method according to an embodiment of the present application;

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

fig. 10a is a schematic diagram of an exemplary propagation delay compensation method provided in 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 yet 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 in an embodiment of the present application;

fig. 13 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 14 is a schematic structural diagram of another communication device according to an embodiment of the present application;

fig. 15 is a schematic structural diagram of a chip according to an embodiment of the present application.

Detailed Description

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

First, in order to better understand the propagation delay compensation method disclosed in the embodiments of the present application, a communication system to which the embodiments of the present application are applicable will be described.

The technical scheme of the embodiment of the application can be applied to various communication systems. For example, the global system for mobile communications, the long term evolution (Long Term Evolution, LTE) system, the fourth Generation (4G) system for mobile communications, the New Radio (NR) system, and with the development of the communications technology, the technical solution of the embodiments of the present application may also be used for the subsequently evolved system for communications, such as the sixth Generation (6 th-Generation, 6G) system for mobile communications, the seventh Generation (7 th-Generation, 7G) system for mobile communications, and so on.

Referring to fig. 1a, fig. 1a is a schematic structural diagram of a communication system according to an embodiment of the present application. The communication system may include, but is not limited to, a network device and a terminal device. Wherein the network device and the terminal device may communicate via a wireless connection, e.g. the network device and the terminal device may communicate via a Uu interface. The number and form of the devices shown in fig. 1a are not meant to limit the embodiments of the present application, and may include two or more network devices and two or more terminal devices in practical applications. The communication system shown in fig. 1a is illustrated by way of example with one network device and one terminal device. In fig. 1a, the network device is exemplified by a base station, and the terminal device is exemplified by 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 referred to as a radio access network device) that accesses the terminal device to a wireless network, where the network device includes, but is not limited to: an evolved Node B (eNB), a radio network controller (radio network controller, RNC), a Node B (Node B, NB), a network device controller (base station controller, BSC), a network device transceiver station (base transceiver station, BTS), a home network device (e.g., home evolved Node B, or home Node B, HNB), a baseband unit (BBU), an Access Point (AP) in a wireless fidelity (wireless fidelity, WIFI) system, a wireless relay Node, a wireless backhaul Node, a transceiver Node (transmission and reception point, TRP), a transmission point (transmission point, TP), and the like; it may also be a device used in a fifth Generation (5 th-Generation, 5G), 6G or even 7G system, such as a gNB in an NR system, or a transmission point (TRP or TP), an antenna panel of one or a group (including multiple antenna panels) of network devices in a 5G system, or a network node constituting a gNB or a transmission point, such as a baseband unit (BBU), or a Distributed Unit (DU), or a Road Side Unit (RSU) in an internet of vehicles (vehicle to everything, V2X) or an intelligent driving scenario.

In some deployments, the network device may include a Centralized Unit (CU), a DU, and the like. The network device may also include a Radio Unit (RU). Wherein the CU implements part of the functions of the network device, the DU implements part of the functions of the network device, for example, the CU implements radio resource control (radio resource control, RRC), the packet data convergence layer protocol (packet data convergence protocol, PDCP) layer, and the DU implements the functions of radio link control (radio link control, RLC), medium access control (media access control, MAC), and Physical (PHY) layer. Since the information of the RRC layer is eventually changed into or converted from the information of the physical layer, under this architecture, higher layer signaling, such as RRC layer signaling or PDCP layer signaling, may also be considered to be transmitted by the DU or by the du+ru. It is understood that the network device may be a CU node, or a DU node, or a device comprising a CU and a DU.

When the network device is a device including a CU and a DU and performs broadcast communication, the network device may communicate with the terminal device through the DU, as shown in fig. 1 b. When the network device is a device including a CU and a DU and performs unicast communication, data sent by the network device to the terminal device needs to be encrypted by the CU and then sent to the terminal device, so that the network device communicates with the terminal device through the CU, as shown in fig. 1 c.

In the embodiment of the application, the terminal device may be a device that provides voice and/or data connectivity to a user. A terminal device may also be referred to as a User Equipment (UE), a terminal, an access terminal, a subscriber unit, a subscriber station, a Mobile Station (MS), a Mobile Terminal (MT), a remote station, a remote terminal, a mobile device, a subscriber terminal, a user agent, or a user equipment, and may be applied to a 4G, 5G, or even 6G system. The terminal device in this embodiment of the present application may be a joint device that performs digital signal transmission and reception on a common telephone line, and may also be a mobile phone (mobile phone), a tablet computer (Pad), a computer with a wireless transceiving function, a Virtual Reality (VR) terminal device, an augmented reality (augmented reality, AR) terminal device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned driving (self driving), a wireless terminal in remote medical (remote medical), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation security (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), an RSU of the aforementioned wireless terminal type, or the like. The terminal device may also be a device capable of side link (sidelink) communication, for example, the terminal device may be an in-vehicle terminal, or a handheld terminal capable of V2X communication, or the like.

In order to facilitate an understanding of the embodiments disclosed herein, the following two descriptions are provided.

(1) In the embodiments disclosed in the present application, the scenario is described by taking the scenario of an NR network in a wireless communication network as an example, and it should be noted that the schemes in the embodiments disclosed in the present application may also be applied to other wireless communication networks, and the corresponding names may also be replaced by names of corresponding functions in other wireless communication networks.

(2) Embodiments of the present disclosure will present various aspects, embodiments, or features of the present disclosure around a system comprising a plurality of devices, components, modules, etc. 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. Furthermore, combinations of these schemes may also be used.

Next, related concepts related to the embodiments of the present application will be briefly described.

1. High precision time synchronization protocol (precision time protocol, PTP)

PTP is a protocol that can be used to achieve accurate time synchronization (timing synchronization) between devices, which can reach sub-microsecond accuracy based on PTP. 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: an Ordinary Clock (OC), a Boundary Clock (BC), and a Transparent Clock (TC). These three types of clock nodes are described below:

(1) There is only one clock port in the OC that can be used to communicate with other clocks in the network. The OC may act as a master clock (grandmaster clock, GM) or a Slave Clock (SC). Wherein, the GM refers to a clock for issuing time information to a downstream node; SC refers to a clock that synchronizes time with an upstream node based on time information received from the upstream node. The time information in the time synchronization process based on the PTP may be carried by a PTP message. For example, when clock 1 sends time information to clock 2 to achieve time synchronization between clock 1 and clock 2, clock 1 is an upstream node and clock 2 is a downstream node.

In addition, the GM may issue time information to the downstream node through a master clock port (i.e., mtort), and the SC may receive time information from the upstream node through a slave clock port (i.e., S-port). For example, in connection with FIG. 2, in FIG. 2, OC-1 acts as a master clock, and OC-2, OC-3, and OC-4 all act as slave clocks.

(2) There are multiple clock ports in the BC, each of which may be used to communicate with other clocks in the network. Among the multiple clock ports of the BC, there is one clock port for synchronizing time with an upstream node, and other clock ports than the clock port are used for issuing time information to the downstream node. For example, in connection with FIG. 2, BC-1 includes port 1, port 2, and port 3; the port 1 is an S port, and can be used for BC-1 to receive time information from TC-1; both port 2 and port 3 are Mports, 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 be kept time synchronized with other clocks. Specifically, after receiving the PTP message from the upstream node, the BC synchronizes the time with the upstream node based on the PTP message, but does not directly forward the received PTP message, but generates a new PTP message based on the PTP message, and then sends the new PTP message to the downstream node. For example, in connection with FIG. 2, after receiving a PTP message from TC-1 via the S port (i.e., port 1), BC-1 generates a new PTP message based on the synchronization time of the PTP message with OC-1, and sends the new PTP message to OC-2 via the M port (i.e., port 2).

(3) There are multiple clock ports in the TC that are used to forward PTP messages. The TC may make a forward delay correction to the PTP message and the TC need not maintain time synchronization with other clocks. Specifically, the TC performs forwarding delay correction on the PTP message, which may include: the TC configures a correction field (correction field) field of the PTP message, which is used to indicate a stay time of the PTP message at the home node, which may also be referred to as a correction value. Thus, after receiving the PTP message, the downstream node of the TC can perform time synchronization based on the time information carried by the PTP message and the correction value indicated by the correction field. For example, in connection with FIG. 2, TC-1 receives a PTP message from OC-1, and sends the PTP message to BC-1 after forward delay correction.

2. Time delay sensitive network (time sensitive network TSN)

The TSN may be applied to industrial control scenarios. In an industrial control scenario, control signaling from a master node (e.g., a console) may reach a slave node (e.g., an operating arm) within a specified time, and the slave node may perform a corresponding operation at the specified point in time, where the industrial control network is typically a TSN. High precision time synchronization protocols are commonly used in TSNs to achieve accurate time synchronization between TSN devices to support time-based operational control. The high-precision time synchronization protocol may be PTP, or institute of electrical and electronics engineers (Institute of Electrical and Electronics Engineers, IEEE) 1588 protocol.

As can be seen, in industrial manufacturing and like scenarios, product line control is typically performed by TSN. At present, TSNs are basically borne on a wired network, and TSNs deployed based on a wired mode have inherent defects of high cable deployment cost, safety risk, low flexibility and the like. If the TSN is deployed based on a wireless manner, the above problem can be effectively avoided, and particularly, the last hop of the TSN network adopts a wireless manner, that is, a wireless connection is adopted between the TSN device and the terminal device. The scheme of the 5G system (5 GS) supporting TSN is discussed in the third generation partnership project (3rd generation partnership project,3GPP) Rel-16. In connection with fig. 3, in the TSN, the 5GS may be regarded as a TSN bridge device (TSN bridge), and the TSN devices may perform uplink transmission or downlink transmission on a service data packet of the TSN through the 5 GS. In addition, in the 5GS TSN-supported scheme, time synchronization in the 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 scheme that the 5G system supports TSN, when the TSN uses PTP to achieve accurate time synchronization between TSN devices, 5GS and PTP adaptation is also required. In the scheme adopted by the 3GPP, the 5GS can be regarded as a transparent clock in the PTP, and then the PTP message sent by the GM in the TSN can be forwarded to the TSN network end equipment through the 5 GS. In addition, the TSN adapter is used to process PTP related messages or packets at the boundary between the 5GS and TSN connections. For example, in connection with fig. 4, a Device side TSN adapter (Device-side TSN Translator, DS-TT) (or referred to as UE-TT) is a TSN adapter used at a connection point between a terminal Device and a TSN Device in 5GS, and the DS-TT may be a processing Device connected to the terminal Device or a logic function of the terminal Device; the network side TSN adapter (network-side TSN translator, NW-TT) is a TSN adapter used at a connection location between a user plane function (User Plane Function, UPF) network element and a TSN device in 5GS, and the NW-TT may be a processing device connected to the UPF or a logic function of the UPF.

The 5GS is used as a transparent clock, and the residence time of the PTP message within the 5GS is required to configure the correctionField field of the PTP message. In order to obtain the residence time of the PTP message within 5GS, it is also necessary to guarantee 5G time synchronization between the terminal device and the UPF in 5 GS. Wherein time synchronization between the terminal device and the UPF is ensured by both retrieving time from the same clock source. Specifically, in connection with fig. 4, the gNB and the 5G GM are time synchronized, and the UE and the UPF are time synchronized with the gNB, respectively, to achieve time synchronization between the UE and the UPF. The UE and the gNB can realize clock synchronization through an air interface synchronization scheme, and the UPF and the gNB can realize clock synchronization through PTP.

The residence time of the PTP message within 5GS is determined based on the 5G time the UPF receives the PTP message from the TSN device and the 5G time the terminal device sends the PTP message to the TSN device. Referring to FIG. 4, when the NW-TT corresponding to the UPF receives the PTP message from the TSN device, a 5G time stamp t is marked _in The method comprises the steps of carrying out a first treatment on the surface of the The 5G time of the DS-TT corresponding to the UE for sending the PTP message to the TSN equipment is t _out The method comprises the steps of carrying out a first treatment on the surface of the Then the residence time of PTP message in 5GS is t _out -t _in 。

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

The 5G air time synchronization is achieved by the network device indicating a 5G time reference point to the terminal device. The network device can perform 5G time service to the terminal device in a broadcast mode or a unicast mode. Wherein, the 5G reference time sent by the network device to the terminal device through broadcasting mode can be carried by a system message block (system information block, SIB) (such as SIB 9); the 5G reference time sent by the network device to the terminal device in a unicast manner may be carried by a downlink message transfer (dlinfo transfer) message.

The following further describes 5G air interface time synchronization by taking the example that the network device performs 5G time service to the terminal device through unicast. In connection with fig. 5, the network device sends a DLInformationTransfer message to the terminal device on a slot with a system frame number (System Frame Number, SFN) of x-3 (i.e. SFN x-3), the DLInformationTransfer message carrying a time T and a time reference point SFN x. The time T is the time corresponding to a time reference point indicated by the network equipment to the terminal equipment; the time reference point may be a certain time position on one or more radio frames transmitted by the network device to the terminal device. For example, the time reference point may be a start position or an end position of a certain radio frame. After receiving the dlinformation transfer message, the terminal device can learn that the 5G reference time corresponding to the radio frame (radio frame) ending position corresponding to the SFN x closest to the moment when the dlinformation transfer message is received is time T. For example, the time reference point is the start position of the radio frame 1, and when the terminal device receives the start position of the radio frame 1, it may determine that the time corresponding to the start position of the radio frame 1 is time T.

PDC can be used for precise time synchronization between devices. When the time synchronization is carried out between the network equipment and the terminal equipment, propagation delay exists in the process of transmitting the signal to the terminal equipment and receiving the signal, namely, the time difference exists between the frame boundary of the downlink signal transmitted by the network equipment and the frame boundary of the downlink signal received by the terminal equipment. In fig. 5, if the time T is the 5G time when the network device sends the radio frame end position corresponding to SFN x, the terminal device needs to perform PDC in the process of performing 5G time synchronization based on the unicast timing message, which includes: the actual 5G time of receiving the radio frame end position corresponding to the SFN x is determined based on the time T and the propagation delay, namely the actual 5G time of receiving the radio frame end position corresponding to the SFN x is the sum of the time T and the propagation delay.

In the embodiment of the application, the PDC performed by the terminal device means that the actual time of the terminal device receiving the time reference point is determined based on the time T and the propagation delay; the network device performing PDC refers to determining, by the network device, an actual time when the terminal device receives the time reference point based on the propagation delay. 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 does not perform PDC for the time reference point, or 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. In addition, in the embodiment of the present application, the network device performing PDC may also be referred to as the network device performing PDC precompensation.

4. Timing Advance (TA) mechanism and TA-based PDC scheme

The essence of the TA mechanism is that the time when the terminal device sends the uplink subframe is advanced by a certain time compared to the time when the terminal device receives the downlink subframe, i.e. there is a negative offset (i.e. TA value) between the start time when the terminal device receives the downlink subframe and the start time when the uplink subframe is transmitted. In the orthogonal multiple access system, the network device appropriately 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 time when the signals from different terminal devices of the same subframe but different frequency domain resources arrive at the network device is basically aligned, thereby ensuring the orthogonality of uplink transmission and avoiding intra-cell interference.

Referring to fig. 6, the terminal device advances the time of the frame boundary of the received downlink signal by 2T _p (i.e., the TA value in the ideal case) transmitting an upstream signal; then the upstream signal goes through T _p The time of arrival at the network device and the time of frame boundaries of the downstream signal transmitted by the network device are aligned. In this way, the time when the uplink signal sent by the terminal device in the cell in the same subframe arrives at the network device is aligned.

The network device may send the TA value to the terminal device via a timing advance command (timing advance command, TAC). Specifically, in the random access procedure, the network device may indicate an absolute TA value through the TAC field; alternatively, the network device indicates the TA adjustment value through a TAC medium access control layer control unit (medium access control control element, MAC CE). For example, the network device sends a TA value of 10s (absolute value) to the terminal device, and if the network device wishes to adjust the TA value to 12s (absolute value), the TA adjustment value may be indicated to the terminal device as 2s.

In the PDC mode based on TA, after receiving the TA value from the network equipment, the terminal equipment can pass throughTo approximate T _p I.e. propagation delay, whereby the PDC is performed based on the determined propagation delay.

In addition, TA-based PDC approaches are limited by TA granularity, such as the bandwidth to which the TA corresponds. Moreover, the terminal device may not apply an accurate TA value due to failure of delivery of the TAC by the MAC CE, so that the TA values applied by the network device and the terminal device are different, and further, the accuracy of time synchronization between the network device and the terminal device is reduced.

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

In the RTT-based PDC manner, the network device and the terminal device respectively transmit reference signals to the opposite end, and the network device measures a difference between a time point when an Uplink (UL) reference signal from the terminal device is received and a time point when a Downlink (DL) reference signal is transmitted, that is, a reception-transmission time difference of the network device; the terminal device measures a difference between a time when the downlink reference signal from the network device is received and a time when the uplink reference signal is transmitted, i.e., a reception-transmission time difference of the terminal device. The value of the receiving-transmitting time difference of the network device can be positive or negative, and depends on the sequence of the network device receiving the uplink reference signal and transmitting the downlink reference signal; similarly, the value of the receiving-transmitting time difference of the terminal device may be positive or negative, depending on the sequence in which the terminal device receives the downlink reference signal and transmits the uplink reference signal.

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

For example, the network device sends a downlink reference signal to the terminal device, and records the sending time t ₁ The method comprises the steps of carrying out a first treatment on the surface of the The terminal equipment receives the downlink reference signal and records the receiving time t ₂ The method comprises the steps of carrying out a first treatment on the surface of the The terminal equipment sends an uplink reference signal to the network equipment and records the sending time t ₃ The method comprises the steps of carrying out a first treatment on the surface of the The network equipment receives the uplink reference signal and records the receiving time t ₄ The method comprises the steps of carrying out a first treatment on the surface of the It can be seen that the receive-transmit time difference of the network device is (t ₄ -t ₁ ) The reception-transmission time difference of the terminal device is (t ₂ -t ₃ ). Then, RTT between the network device and the terminal device is (t ₄ -t ₁ )+(t ₂ -t ₃ ) The method comprises the steps of carrying out a first treatment on the surface of the Propagation delay of

The RTT and propagation delay may be determined by the terminal device or the network device. In the process of determining the RTT and the propagation delay by the terminal device in connection with fig. 7a, 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, and the terminal device calculates the RTT and the propagation delay based on the receiving-sending time difference of the network device and the determined receiving-sending time difference of the terminal device. In connection with fig. 7b, in the process that the RTT and the propagation delay are determined by the network device, the terminal device needs to send the receiving-sending time difference of the network device to the network device after determining the receiving-sending time difference of the terminal device, and the network device calculates the RTT and the propagation delay based on the receiving-sending time difference of the terminal device and the determined receiving-sending time difference of the network device, and sends the determined propagation delay to the terminal device.

In addition, the RTT-based PDC scheme may satisfy a more severe time synchronization accuracy level than the TA-based PDC scheme. Thus, TA-based PDC approaches are generally used as alternatives to RTT-based PDC approaches.

In the embodiment of the present application, the receiving-transmitting time difference of the terminal device may also be referred to as UE _{Receiving terminal (receiving)} _{End, rx) -sender (Transmit} _End ， _Tx) The method comprises the steps of carrying out a first treatment on the surface of the When the network device is a gNB, the time difference between receiving and transmitting of the network device may also be referred to as a gNB _Rx-Tx 。

In the process of time synchronization between the network equipment and the terminal equipment, since propagation delay exists when the wireless frame is transmitted between the network equipment and the terminal equipment, the propagation delay can influence the time synchronization between the network equipment and the terminal equipment, and therefore PDC (polycrystalline diamond compact) is also needed to be carried out when the network equipment and the terminal equipment are in time synchronization.

If the network equipment carries out PDC, the time T after PDC is sent to the terminal equipment, namely, the actual time of the determined time reference point is sent to the terminal equipment; the terminal device receives the time T, but does not know the actual time of the time reference point determined by the network device, and the terminal device may perform PDC on the time T, so that the actual time of the time reference point determined by the terminal device may be greatly different from the actual time of the time reference point determined by the network device, and further, the accuracy of time synchronization between the terminal device and the network device is lower.

The embodiment of the application provides a propagation delay compensation method, in which a network device determines a first message and sends the first message to a terminal device, wherein the first message is used for indicating whether the network device allows the terminal device to perform PDC on time T, and the time T is a reference time for air interface time synchronization indicated to the terminal device by the network device. Correspondingly, 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, effectively enhances the coordination degree of time synchronization between the terminal equipment and the network equipment, thereby avoiding the reduction of the accuracy of the time synchronization caused by the PDC carried out by the network equipment and the terminal equipment, and the terminal equipment can flexibly select the PDC mode to carry out the PDC based on the configuration condition of RTT measurement, which is beneficial to realizing the high-precision time synchronization between the network equipment and the terminal equipment.

Embodiments of the present application are further described below with reference to the accompanying drawings.

Referring to fig. 8, fig. 8 is a flowchart of a propagation delay compensation method according to an embodiment of the present application, where the propagation delay compensation method is illustrated from the interaction point of the network device and the terminal device. The propagation delay compensation method comprises the following steps:

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

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

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

S103, the terminal equipment determines whether the PDC is allowed to be carried out on the time T according to the first message.

Wherein, when the first message is used to instruct the network device to allow the terminal device to PDC the time T, the terminal device may determine that the terminal device is allowed to PDC the time T; the terminal device may determine that PDC of time T is prohibited when the first message is used to instruct the network device not to allow the terminal device to PDC of time T.

In an alternative embodiment, the first message includes a first field; when the network device allows the terminal device to perform PDC on the time T, a first field indicates enabling (enabling); when the network device prohibits the terminal device from PDC for time T, the first field indicates disable. Correspondingly, the determining, by the terminal device, whether to allow PDC to be performed on the time T according to the first message may include: when the first message comprises a first field and the first field indicates enable (enable), the terminal equipment determines that the terminal equipment is allowed to carry out PDC on time T; the terminal device determines that the terminal device is barred from PDC for time T when the first message includes a first field and the first field indicates disable. Wherein the first field may be an optionally present field in the RRC message.

In addition, the first field may also use a representation indicating true or false in addition to a representation indicating enable or disable. Correspondingly, when the first field indicates true, the terminal equipment determines that the terminal equipment is allowed to carry out PDC on the time T; when the first field indicates false, it is determined that the terminal device is prohibited from PDC the time T. Or, the first field may also take a numerical expression form, for example, when the numerical value carried by the first field is 1, the terminal device determines that the terminal device is allowed to perform PDC on time T; and when the value carried by the first field is 0, determining that the terminal equipment is forbidden to carry out PDC on the time T. In the embodiment of the present application, the representation form of the first field is not limited.

And S104, when the terminal equipment determines that the PDC is allowed to be carried out on the time T, the PDC is carried out on the time T according to the configuration condition of Round Trip Time (RTT) measurement.

When determining that the PDC is allowed to be performed on the time T, the terminal device may select, based on the following several embodiments, a PDC method adopted for performing the PDC from a TA-based PDC method and an RTT-based PDC method.

In embodiment 1, when RTT measurement is configured, a terminal device performs PDC on time T based on RTT; when RTT measurements are not configured, PDC is performed for time T based on TA. In this embodiment, whether or not the RTT measurement is configured as a switch for determining the PDC method is determined by the terminal device, so that the PDC is performed on the time T based on the determined PDC method. In this case, the default terminal device configures RTT measurement, there is always an available RTT measurement result at the terminal device, i.e. the terminal device performs PDC on time T based on the available RTT measurement result when the terminal device configures RTT measurement. Wherein the RTT measurement result comprises a reception-transmission time difference of the network device and/or a reception-transmission time difference of the terminal device. Then, when the RTT measurement is configured, the terminal device may calculate RTT based on the reception-transmission time difference of the terminal device and the reception-transmission time difference of the network device received from the network device, and further perform PDC on time T based on RTT, to determine the actual time of the time reference point.

In this embodiment, the terminal device configuring RTT measurement refers to that the terminal device has an RTT measurement function, that is, the terminal device has a capability of determining a receiving-transmitting time difference of the terminal device, a receiving-transmitting time difference of the receiving network device, and determining a propagation delay based on the receiving-transmitting time difference of the terminal device and the receiving-transmitting time difference of the network device.

In embodiment 2, when RTT measurement is configured and there is a usable RTT measurement result, the terminal device performs PDC on time T based on the RTT measurement result; determining not to perform PDC on time T when RTT measurement results which can be used are configured, or performing PDC on time T based on RTT measurement results when RTT measurement results which can be used are received; when RTT measurements are not configured, PDC is performed for time T based on TA. In this embodiment, it can be seen that, in comparison with embodiment 1, the terminal device takes into account the fact that the terminal device has configured RTT measurement and no usable RTT measurement, and further clarifies the behavior of the terminal device in this case, as a switch for determining the PDC scheme.

In embodiment 3, when RTT measurement is configured and the existing RTT measurement result is within the validity period, the terminal device performs PDC on time T based on the RTT measurement result; determining that PDC is not performed on the time T when RTT measurement is configured and the existing RTT measurement result is not in the effective period, or performing PDC on the time T based on the received RTT measurement result when the RTT measurement result is received in the preset duration; when RTT measurements are not configured, PDC is performed for time T based on TA.

That is, when the terminal device configures RTT measurement and the existing RTT measurement result is not within the validity period, if the next RTT measurement result reaches the terminal device within a time range acceptable to the terminal device (i.e., a preset duration), the terminal device may perform PDC on the time T based on the received next RTT measurement result; if the time of the next RTT measurement result reaching the terminal device exceeds the acceptable time range of the terminal device, the terminal device may not perform PDC on time T.

As can be seen, in embodiment 3, the terminal device takes into consideration whether or not the RTT measurement is configured and whether or not the existing RTT measurement result is within the validity period as a switch for determining the PDC scheme, and compared with embodiment 1, the terminal device has fully considered the case that the terminal device is configured with the RTT measurement and the existing RTT measurement result is not within the validity period, and further clarifies the behavior of the terminal device in this case. In the case where the network device periodically issues RTT measurement results (including a reception-transmission time difference of the network device) to the terminal device configured with RTT, and the RTT measurement results from the network device received by the terminal device when the RTT-based PDC is performed have exceeded the validity period, embodiment 3 may avoid that the terminal device uses the RTT measurement results exceeding the validity period to perform the PDC on time T, which affects the accuracy of time synchronization between the network device and the terminal device.

Optionally, the preset duration may be manually configured, or may be determined by negotiation between the network device and the terminal device. The method for determining the preset time length is not limited.

Alternatively, whether the RTT measurement result is within the validity period may be determined by the terminal device through a Timer (Timer). Specifically, when the timer is in an operating state, the terminal equipment determines that an RTT measurement result is in an effective period; and determining that the RTT measurement result is not within the validity period when the timer is in a stopped state. In addition, the timer being in a stopped state may be caused by the absence of available RTT measurement results by the terminal device, in addition to the RTT measurement results exceeding the validity period; in this case, the terminal device may still perform: and determining that the PDC is not carried out on the time T, or carrying out the PDC on the time T based on the received RTT measurement result when the available RTT measurement result is received in the preset duration. In the embodiment of the application, the timer may also be referred to as RTT measurement valid timer (RTT result validity timer).

Optionally, the propagation delay compensation method may further include: when receiving RTT measurement results (i.e. a reception-transmission time difference) from the network device, the terminal device starts a timer, so that the timer is in an operation state (may also be referred to as an on state); if the timer times out, the terminal device stops the timer so that the timer is in a stopped state (may also be called a closed state); the terminal device re-receives the RTT measurement result from the network device again The timer is started up again so that it is in operation again. For example, in connection with fig. 9, the period of the receive-transmit time difference for the network device to transmit to the network device is t ₃ -t ₁ The effective period is t ₂ -t ₁ . The terminal device is at t ₁ The receiving-transmitting time difference #1 of the network equipment is received at the moment, and a timer is started; the timer is at t ₂ The terminal device stops the timer when the time exceeds the valid period; until the terminal device is at t ₃ The reception-transmission time difference #2 of the network device is received at the moment, and the timer is started again.

In an alternative embodiment, when the terminal device determines that PDC is prohibited from being performed on time T, the propagation delay method may further include: when the terminal device configures RTT measurement, the latest receiving-transmitting time difference of the terminal device is transmitted to the network device. When the terminal equipment is not configured with RTT measurement, the behavior of the terminal equipment is not affected. It can be seen that the condition that the terminal device is prohibited from PDC to time T and RTT measurement is configured, the terminal device may be triggered to report the reception-transmission time difference of the terminal device in UL, so that the network device may perform pre-compensation of PDC based on the reception-transmission time difference of the terminal device.

In an alternative embodiment, the propagation delay compensation method may further include: 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, and the first field is not included in the first message (or the first field indicates null). Correspondingly, when the first message does not include the first field, that is, the first field does not exist (absent) (or the first field indicates that the first field is empty), the terminal device performs PDC according to a preset PDC mode. The preset PDC method may be a PDC method configured for the terminal device, or may be a PDC method preset manually. That is, the terminal device may fall back to R16 behavior when the first field is not present, i.e., the terminal device may perform PDC according to its implementation. For example, the terminal device may perform PDC according to a PDC manner configured in advance for the terminal device by the manufacturer. In this case, the network device does not pre-compensate the PDC for the time T, so as to avoid the degradation of accuracy of time synchronization caused by the PDC performed by both the terminal device and the network device.

As can be seen, the network device may configure that the first field exists and indicates enabled (enabled) or disabled (disabled), or that the first field does not exist (enabled). The terminal device may determine whether to perform PDC based on the first field and whether the terminal device is configured with RTT test, as shown in fig. 10 a. Alternatively, the terminal device may determine whether to perform PDC based on the first field, whether the terminal device has configured RTT measurement, and whether there is an RTT measurement result that can be used, as shown in fig. 10 b. Still alternatively, the terminal device may determine whether to perform PDC based on the first field, whether the terminal device is configured with RTT measurements, and whether the existing RTT measurements are within a validity period, as shown in fig. 10 c.

In another alternative embodiment, the first message may include a first indication indicating whether the network device allows the terminal device to PDC the time T. Correspondingly, the determining, by the terminal device, whether to allow PDC to be performed on the time T according to the first message may include: when the first indication is used for indicating the network equipment to allow the terminal equipment to carry out PDC on the time T, the terminal equipment is determined to be allowed to carry out PDC on the time T; and when the first indication is used for indicating that the network equipment does not allow the terminal equipment to carry out PDC on the time T, the terminal equipment determines that the terminal equipment is forbidden to carry out PDC on the time T. In this embodiment, the terminal device may determine whether to allow PDC to be performed on the time T based on the first indication, and further may determine whether to perform PDC on the time T, which effectively enhances the coordination degree of time synchronization between the terminal device and the network device.

Alternatively, the first indication may indicate by a value whether the network device allows the terminal device to PDC the time T. For example, when the first indication corresponds to a value of 0, the indication does not allow the terminal device to PDC the time T, i.e. the terminal device is prohibited from PDC the time T; when the first indication corresponds to a value of 1, the indication allows the terminal device to PDC the time T, i.e. the terminal device is allowed to PDC the time T. Alternatively, the first indication may indicate that the terminal device is allowed to PDC the time T by "true" and that the terminal device is not allowed to PDC the time T by "false". In this embodiment, the first indication indicates whether the network device allows the terminal device to perform PDC on the time T, which is not limited.

In an alternative embodiment, the first message further comprises a second indication indicating whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode. Correspondingly, when the terminal equipment determines that the PDC is allowed to be performed on the time T, the propagation delay compensation method can further comprise: and the terminal equipment performs PDC on the time T according to the PDC mode indicated by the second indication. Alternatively, the second indication may indicate by a value 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, the indication PDC method is a TA-based PDC method; and when the second indication corresponds to the value 1, indicating that the PDC mode is the PDC mode based on RTT. In the embodiment of the present application, the second indication indicates whether the PDC method is a TA-based PDC method or an RTT-based PDC method, and the representation form is not limited. It can be seen that in this embodiment, the network device may provide flexible PDC mode selection for the terminal device, which may determine the PDC mode based on the indication of the network device. In addition, the PDC mode indicated by the network equipment for the terminal equipment can be determined based on the requirement of the service on time synchronization precision, so that the PDC mode adopted by the terminal equipment can meet the requirement of the service on time synchronization precision.

Optionally, when the first indication in the first message is used to indicate that the terminal device does not perform PDC on time T, the second indication may be set to a default value. That is, when the terminal device is prohibited from PDC the time T, the PDC method is not considered any more, and the terminal device may not execute the PDC operation on the time T according to the PDC method indicated by the second indication.

Alternatively, in the above embodiment, the first indication and the second indication may be carried by 1bit fields, respectively. Specifically, the network device may add a 2bit field in the RRC message, where the 1bit field is used to carry the first indication, and the other 1bit field is used to carry the second indication. In connection with fig. 11, taking the representation forms of the first indication and the second indication as numerical values as an example, the first indication carried by the 1bit field may indicate whether the terminal device is allowed to PDC the time T through the numerical value a1, and the second indication carried by the 1bit field may indicate whether the PDC mode is a TA-based PDC mode or an RTT-based PDC mode through the numerical value a 2. If the terminal equipment receives a1 equal to 0, the terminal equipment can determine that PDC is forbidden to be carried out on the time T; if a1 is received equal to 1, then it may be determined that PDC is allowed for time T. In addition, when the network device configuration a1 is 0, a2 may be set to 0 by default. If the terminal equipment receives that a1 is equal to 0, the value of a2 can be not considered any more; and if the received a1 is equal to 1, determining the PDC mode based on the a 2. Specifically, if the terminal device receives that a2 is equal to 0, the PDC mode can be determined to be a TA-based PDC mode; if a2 is equal to 1, then the PDC mode may be determined to be an RTT-based PDC mode.

In summary, in the propagation delay compensation method, 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 PDC on time T, and the time T is a reference time indicated by the network device to the terminal device for air interface time synchronization. Correspondingly, 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 terminal equipment determines that the PDC is allowed to be carried out on the time T, carrying out the PDC on the time T according to the configuration condition of RTT measurement. Therefore, the method can realize that the network equipment controls the terminal equipment to carry out PDC, effectively enhances the matching degree of time synchronization between the terminal equipment and the network equipment, and can avoid the reduction of accuracy of the time synchronization caused by PDC both carried out by the terminal equipment and the network equipment, thereby being beneficial to realizing high-accuracy time synchronization between the terminal equipment and the network equipment. In addition, the method also defines a message format (such as a first indication, a second indication or a first field) of the first message that the network device indicates whether the PDC is allowed for the terminal device, and defines that the terminal device can flexibly select the PDC mode from the TA-based PDC mode and the RTT-based PDC mode according to the configuration condition of RTT measurement to perform the PDC.

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

In an alternative embodiment, the network device determining the first message may include: 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, it determines the first message. The network device sending a first message to the terminal device may include: the DU transmits a first message to the terminal device, the first message being an RRC broadcast message. This embodiment is applicable to a broadcast scenario, where it is decided by the DU whether the terminal device is allowed to PDC the time T.

Optionally, the default format of the first message may include a format corresponding to the first field. Accordingly, determining the first message when the DU receives the second message may include: the DU may determine whether the first field indicates enabled or disabled based on whether the terminal device is allowed to PDC the time T, and modify information carried in the first field according to the determination result to determine the first field transmitted to the terminal device. Alternatively, the DU may determine that the first field is present and indicates enabled or disabled, or that the first field is not present. Correspondingly, when the first message comprises a first field and the first field indicates that the first message is enabled, the terminal equipment determines that PDC is allowed to be carried out on time T; determining that the terminal device is prohibited from PDC the time T when the first message includes the first field and the first field indicates that the first field is not enabled; when the first field is not present in the first message, rollback to R16 behavior. The description of the first field can be referred to as a description of the propagation delay compensation method shown in fig. 8, and 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. Accordingly, determining the first message when the DU receives the second message may include: the DU determines whether the terminal device is allowed to PDC the time T and modifies the information carried in the first indication according to the determination result to determine the first indication to be sent to the terminal device. Correspondingly, when the first indication is used for indicating the network equipment to allow the terminal equipment to perform PDC on the time T, the terminal equipment can determine that the PDC is allowed to be performed on the time T; and determining that PDC is forbidden to be performed on the time T when the first indication is used for indicating that the network equipment does not allow the terminal equipment to perform PDC on the time T.

And/or, determining a PDC mode used by the terminal equipment when the terminal equipment is allowed to carry out PDC on the time T by the DU, and modifying information carried in the second indication according to a determination result to determine the second indication sent to the terminal equipment. Then, the terminal device may perform PDC on the time T according to the PDC manner indicated by the second indication. The description of the first indication and the second indication can be referred to as the description of the propagation delay compensation method shown in fig. 8, and 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, which may be a fake or invalid time; the DU determines a reference time to modify the default reference time and takes the determined reference time as time T. In addition, the default reference time and the default format of the first message sent by the CU to the DU may be carried by the same signaling, or may also be carried by different signaling. In this embodiment, the default reference time and the default format of the first message sent by the CU to the DU may also be collectively referred to as the source message. When the RRC broadcast message is SIB9, the source message may be sent by the CU to the DU through the F1 interface.

In another alternative embodiment, the network device determining the first message may include: the DU sends a second message to the CU, wherein the second message comprises a first indication, a second indication or a value of a first field in the first message; when the CU receives the second message, the CU determines the first message. The network device sending a first message to the terminal device may include: the CU sends a first message to the terminal device, the first message being an RRC unicast message. This embodiment may be applied in a unicast scenario, where the DU decides whether to allow the terminal device to PDC the time T, and the CU may directly forward the received first indication, second indication or value of the first field from the DU to the terminal device. For the description of the first indication, the second indication and the first field, reference may be made to the description of the propagation delay compensation method shown in fig. 8, which is not repeated here.

Optionally, the DU may also send a time T to the CU, which may be the time after the DU performs PDC pre-compensation, or the time when the DU does not perform PDC pre-compensation. The DU may perform PDC pre-compensation based on the TA PDC scheme to determine the time T, or the DU may perform PDC pre-compensation based on the RTT PDC scheme to determine the time T. In addition, when the DU performs PDC pre-compensation based on the RTT PDC method, it is also required to request to the CU to obtain a reception-transmission time difference of the terminal device to determine the time T.

Optionally, the propagation delay compensation method may further include: the first field indication may be determined not to be enabled when the DU is at a time T that is after the pre-compensation of the PDC by the DU. Accordingly, when the first message includes the first field and the first field indicates that the first field is not enabled, the terminal device determines that the terminal device is prohibited from PDC for time T. That is, if the DU has already performed the pre-compensation of the PDC, the terminal device does not need to perform the PDC, and this embodiment can avoid the degradation of accuracy of time synchronization caused by both the terminal device and the network device performing the PDC.

In addition, the DU may determine that the first field indicates enabled or disabled when time T is a time when the DU does not pre-compensate for the PDC. Correspondingly, when the first message comprises a first field and the first field indicates that the first field is enabled, the terminal equipment determines that the terminal equipment is allowed to carry out PDC on time T; when the first message includes a first field and the first field indicates that it is not enabled, it is determined that the terminal device is disabled from PDC for time T. That is, the DU does not perform pre-compensation of the PDC, and the terminal device may determine whether to allow PDC for time T based on the indication of the first field.

Optionally, the propagation delay compensation method may further include: when the DU is a time when pre-compensation of the PDC is not performed at time T, it may be determined that the first field exists and indicates enabled or disabled, or the first field does not exist. And the terminal equipment returns to the R16 action when the first field in the received first message does not exist. Regarding the related operations of the terminal device when the PDC is allowed to be performed on the time T, the related operations when the PDC is forbidden to be performed on the time T, and the related contents of the R16 behavior can be referred to the related description in the propagation delay compensation method shown in fig. 8, which is not repeated here.

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

In yet another alternative embodiment, the network device determining the first message may include: the DU sends a second message to the CU, the second message comprising the value of time T and the value of PDC; the CU determines the first message from the value of time T and the value of PDC. The network device sending a first message to the terminal device may include: the CU sends a first message to the terminal device, the first message being an RRC unicast message. This embodiment is applicable to unicast scenarios, where the CU decides whether to allow the terminal device to PDC the time T. Alternatively, the DU may send the value of time T and the value of PDC to the CU through interface F1.

Alternatively, the value of PDC may be determined by the DU by means of TA-based PDC, or may be determined by the DU by means of RTT-based PDC. When determining the value of the PDC by the PDC based on RTT, the DU needs to request to the CU to obtain a receiving-transmitting time difference of the terminal device to determine the value of the PDC. In the embodiments of the present application, the value of 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, and may include: if the CU decides to pre-compensate PDC, sending the sum of the time T and the PDC value and a first field indicating non-enabling to the terminal equipment; accordingly, the terminal device may determine that the terminal device is prohibited from PDC the time T when the first message includes the first field and the first field indicates that it is not enabled.

In addition, if the CU decides not to pre-compensate the PDC, the value of the PDC is discarded, and a first field indicating enable or disable is sent to the terminal device, or the first field is configured to be absent. Correspondingly, when the first message comprises a first field and the first field indicates that the first field is enabled, the terminal equipment determines that the terminal equipment is allowed to carry out PDC on time T; determining that the terminal device is prohibited from PDC the time T when the first message includes the first field and the first field indicates that the first field is not enabled; when the first field is not present in the first message, rollback to R16 behavior. Therefore, when the CU performs PDC pre-compensation, the CU indicates that the terminal equipment does not perform PDC any more, and the time synchronization precision reduction caused by PDC both performed by the terminal equipment and the network equipment can be avoided. In addition, the DU may send the values of time T and PDC to the CU through interface F1. Regarding the related operations when the terminal device is allowed to PDC the time T, the related operations when the terminal device is forbidden to PDC the time T, and the related content of the R16 behavior can be referred to the related description in the propagation delay compensation method shown in fig. 8, which is not repeated here.

In addition, the propagation delay compensation method provided in the embodiment of the present application may be applied to a Side Link (SL) communication scenario as shown in fig. 12, in addition to a scenario of communication between a network device and a terminal device. The side link communication scenario includes a first terminal device and a second terminal device. The communication between the first terminal device and the second terminal device may be performed via a side link interface, i.e. a side link transmission (SL transmission).

Wherein the first terminal device is operable to determine a first message; and is further operable to send a first message to the second terminal device; the first message is used for indicating whether the first terminal equipment allows the second terminal equipment to perform PDC on time T, and the time T is a reference time for air interface time synchronization, which is indicated to the second terminal equipment by the first terminal equipment. The second terminal device is operable to receive a first message from the first terminal device; the second terminal device may be further configured to determine, according to the first message, whether PDC is allowed for the time T; the second terminal device may be further configured to, when determining that PDC is allowed to be performed on the time T, perform PDC on the time T according to a configuration condition of RTT measurement. In addition, the first terminal device may further perform related operations of the network device in the foregoing method embodiment, and the second terminal device may further perform related operations of the terminal device in the foregoing method embodiment, which are not described herein.

Fig. 13 and 14 are schematic structural diagrams of possible communication devices according to embodiments of the present application. These communication devices can implement the functions of the terminal device or the network device in the above method embodiment, so that the beneficial effects of the above method embodiment can also be implemented. In this embodiment of the present application, the communication device may be a network device in the communication system shown in fig. 1a, fig. 1b, or fig. 1c, or may be a terminal device in the communication system, or may be a module (such as a chip) applied to the terminal device or the network device.

As shown in fig. 13, the communication apparatus 1300 includes a communication unit 1301 and a processing unit 1302. The communications apparatus 1300 can be configured to implement the functions of the network device or the terminal device in the above-described method embodiments.

When the communication apparatus 1300 is used to implement the functions of the terminal device in the above-described method embodiment: a communication unit 1301 configured to receive a first message from a network apparatus, where the first message is configured to instruct the network apparatus whether the communication apparatus 1300 is allowed to perform propagation delay compensation PDC for a time T; time T is a reference time for air time synchronization indicated by the network device to the communication apparatus 1300. A processing unit 1302, configured to determine whether PDC is allowed for time T according to the first message; the processing unit 1302 is further configured to determine that PDC is allowed to be performed on the time T, and perform PDC on the time T according to the configuration of the round trip time RTT measurement.

In an alternative embodiment, the processing unit 1302 determines, according to the first message, whether PDC is allowed for the time T, specifically for: determining that the communication device 1300 is permitted to PDC the time T when the first message includes a first field and the first field indicates enable; when the first message includes a first field and the first field indicates disable is not enabled, it is determined that communication device 1300 is disabled from PDC for time T. Optionally, the processing unit 1302 is further configured to perform PDC according to a preset PDC mode when the first field is not included in the first message.

In an alternative embodiment, when the processing unit 1302 determines that the communication device 1300 is allowed to PDC the time T, the processing unit is specifically configured to PDC the time T according to the configuration of RTT measurement: when RTT measurement is configured, PDC is carried out on the time T based on RTT; when RTT measurements are not configured, PDC is performed for time T based on timing advance TA.

In an alternative embodiment, when the processing unit 1302 determines that the communication device 1300 is allowed to PDC the time T, the processing unit is specifically configured to PDC the time T according to the configuration of RTT measurement:

when the RTT measurement is configured and a usable RTT measurement result exists, PDC is carried out on the time T based on the RTT measurement result;

Determining not to perform PDC on time T when RTT measurement results which can be used are configured, or performing PDC on time T based on RTT measurement results when RTT measurement results which can be used are received;

when RTT measurements are not configured, PDC is performed for time T based on timing advance TA.

In an alternative embodiment, when the processing unit 1302 determines that the communication device 1300 is allowed to PDC the time T, the PDC is performed on the time T according to the configuration of the round trip delay RTT measurement, which is specifically configured to:

when the RTT measurement is configured and the existing RTT measurement result is within the effective period, PDC is carried out on the time T based on the RTT measurement result;

determining that PDC is not performed on the time T when RTT measurement is configured and the existing RTT measurement result is not in the effective period, or performing PDC on the time T based on the received RTT measurement result when the RTT measurement result is received in the preset duration;

In an alternative embodiment, whether the RTT measurement is within the validity period is determined by the processing unit by means of a timer.

In an alternative embodiment, when the processing unit 1302 determines that the communication apparatus 1300 is prohibited from PDC the time T, the processing unit is further configured to: when RTT measurement is configured, the latest reception-transmission time difference of the communication apparatus 1300 is transmitted to the network device.

When the communications apparatus 1300 is configured to implement the functions of the network device in the above-described method embodiment: a processing unit 1302, configured to determine a first message, where the first message is used to instruct the network device 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; a communication unit 1301 configured to send a first message to a terminal device.

In an alternative embodiment, the first message includes a first field; the communication apparatus 1300 indicates enable when the terminal device is allowed to PDC the time T; when the communication apparatus 1300 prohibits the terminal device from PDC for time T, the first field indicates disable is not enabled; the second indication is used for the terminal device to determine the PDC mode. Optionally, when the communication apparatus 1300 does not indicate whether the terminal device is allowed to PDC the time T or is prohibited from PDC the time T, the first field is not included in the first message.

In an alternative embodiment, the communication device 1300 is an architecture in which the distributed units DU are separated from the centralized units CU,

the processing unit 1302 determines a first message, specifically for: sending, by the CU, a second message to the DU, the second message including a default format of the first message; determining the first message when the DU receives the second message;

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

the processing unit 1302 determines a first message, specifically for: sending a second message to the CU through the DU, wherein the second message comprises a value of a first field in the first message; when the CU receives the second message, determining a first message;

the communication unit 1301 sends a first message to the terminal device, specifically for: the first message is sent to the terminal device by the CU, the first message being an RRC unicast message.

the processing unit 1302 determines a first message, specifically for: sending a second message to the CU through the DU, wherein the second message comprises the value of the time T and the value of the PDC; the CU determines a first message according to the value of the time T and the value of the PDC;

For more details on the above-mentioned communication device 1300, reference may be made to the related descriptions in the above-mentioned method embodiments, which are not repeated here.

As shown in fig. 14, the communication device 1400 may be a terminal device or a network device, a chip system, a processor, or the like that supports the terminal device to implement the method, or a chip, a chip system, a processor, or the like that supports the network device to implement the method. The device can be used for realizing the method described in the method embodiment, and can be particularly referred to the description in the method embodiment.

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, etc. 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 may be used to process communication protocols and communication data, and the central processor may be used to control communication devices (e.g., base stations, baseband chips, terminals, terminal chips, DUs or CUs, etc.), execute software programs, and process data of the software programs.

Optionally, the communication device 1400 may include one or more memories 1402 on which instructions 1404 may be stored, which may be executed on the processor 1401, to cause the communication device 1400 to perform the methods described in the method embodiments above. Optionally, the memory 1402 may also store data therein. The processor 1401 and the memory 1402 may be provided separately or may be integrated.

Memory 1402 may include, but is not limited to, nonvolatile Memory such as Hard Disk Drive (HDD) or Solid State Drive (SSD), random access Memory (Random Access Memory, RAM), erasable programmable read-Only Memory (Erasable Programmable ROM, EPROM), ROM or portable read-Only Memory (Compact Disc Read-Only Memory, CD-ROM), and the like.

Optionally, the communication device 1400 may also include a transceiver 1405, an antenna 1406. The transceiver 1405 may be referred to as a transceiver unit, a transceiver circuit, or the like, for implementing a transceiver function. The transceiver 1405 may include a receiver, which may be referred to as a receiver or a receiving circuit, etc., for implementing a receiving function; the transmitter may be referred to as a transmitter or a transmitting circuit, etc., for implementing a transmitting function.

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

In another possible design, processor 1401 may include a transceiver to implement the receive and transmit functions. For example, the transceiver may be a transceiver circuit, or an interface circuit. The transceiver circuitry, interface or interface circuitry for implementing the receive and transmit functions may be separate or may be integrated. The transceiver circuit, interface or interface circuit may be used for reading and writing codes/data, or the transceiver circuit, interface or interface circuit may be used for transmitting or transferring signals.

In yet another possible design, the processor 1401 may have instructions 1403 stored thereon, where the instructions 1403 run on the processor 1401, which may cause the communication device 1400 to perform the method described in the method embodiments above. Instructions 1403 may be solidified in processor 1401, in which case processor 1401 may be implemented in hardware.

In yet another possible design, communication device 1400 may include circuitry that may perform the functions of transmitting or receiving or communicating in the foregoing method embodiments. The processors and transceivers described in embodiments of the present application may be implemented on integrated circuits (integrated circuit, ICs), analog ICs, radio frequency integrated circuits (radio frequency integrated circuit, RFIC), mixed signal ICs, application specific integrated circuits (application specific integrated circuit, ASIC), printed circuit boards (printed circuit board, PCB), electronics, and the like. The processor and transceiver may also be fabricated using a variety of IC process technologies such as complementary metal oxide semiconductor (complementary metal oxide semiconductor, CMOS), N-type metal oxide semiconductor (NMOS), P-type 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 apparatus described in the above embodiment may be a terminal device, a network device, or an access network device, but the scope of the communication apparatus described in the embodiment of the present application is not limited thereto, and the structure of the communication apparatus may not be limited by fig. 14. The communication means may be a stand-alone device or may be part of a larger device. For example, the communication device may be:

(1) A stand-alone integrated circuit IC, or chip, or a system-on-a-chip or subsystem;

(2) A set of one or more ICs, optionally including storage means for storing data, instructions;

(3) An ASIC, such as a modem;

(4) Modules that may be embedded within other devices;

(5) Receivers, terminals, smart terminals, cellular telephones, wireless devices, handsets, mobile units, vehicle 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, reference may be made 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 a plurality. 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 embodiments of the present application: an interface 1502 for receiving a first message from a network device, the first message being for indicating whether the network device allows the chip 1500 to perform propagation delay compensation PDC for time T; the time T is a reference time indicated by the network device to the chip 1500 for air interface time synchronization; a processor 1501 for determining from the first message whether PDC is allowed for time T; the processor 1501 is further configured to determine that PDC is allowed for the time T, and then PDC is performed for the time T according to the configuration of the round trip time RTT measurement.

In another design, for the case where the chip is used to implement the functions of the network device in the embodiments of the present application: a processor 1501 for determining a first message, the first message being for indicating whether the chip 1500 allows the terminal device to make propagation delay compensation PDC for time T; the time T is a reference time indicated to the terminal device by the chip 1500 for air-interface time synchronization. An interface 1502 for sending a first message to a terminal device.

The communication device 1400 and the chip 1500 in the embodiments of the present application may also perform the implementation manner described in the communication device 1300. Those of skill would further appreciate that the various illustrative logical blocks (illustrative logical block) and steps (steps) described in connection with the embodiments herein may be implemented as electronic hardware, computer software, or combinations of both. Whether such functionality is implemented as hardware or software depends upon the particular application and design requirements of the overall system. Those skilled in the art may implement the described functionality in varying ways for each particular application, but such implementation is not to be understood as beyond the scope of the embodiments of the present application.

The technical effects brought by the embodiments of the present application and the embodiments of the above method are the same based on the same conception, and the specific principle is referred to the description of the embodiments of the above method, which is not repeated here.

The present application also provides a computer readable storage medium storing computer software instructions which, when executed by a communications device, implement the functions of any of the method embodiments described above.

The present application also provides a computer program product for storing computer software instructions which, when executed by a communications device, implement the functions of any of the method embodiments described above.

The present application also provides a computer program which, when run on a computer, implements the functions of any of the method embodiments described above.

In the above embodiments, the implementation may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, 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 a computer, the processes or functions described in accordance with embodiments of the present application are produced in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital subscriber line (digital subscriber line, DSL)) or wireless (e.g., 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, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., high-density digital video disc (digital video disc, DVD)), or a semiconductor medium (e.g., solid state disk (solid state drive, SSD)), etc.

In the various embodiments of the application, if there is no specific description or logical conflict, terms and/or descriptions between the various embodiments are consistent and may reference each other, and features of the various embodiments may be combined to form new embodiments according to their inherent logical relationships.

In the present application, "at least one" means one or more, and "a plurality" means two or more. "and/or", describes an association relationship of an association object, and indicates that there may be three relationships, for example, a and/or B, and may indicate: a alone, a and B together, and B alone, wherein a, B may be singular or plural. In the text description of the present application, the character "/", generally indicates that the associated object is an or relationship.

It will be appreciated that the various numerical numbers referred to in the embodiments of the present application are merely for ease of description and are not intended to limit the scope of the embodiments of the present application. The sequence number of each process does not mean the sequence of the execution sequence, and the execution sequence of each process should be determined according to the function and the internal logic.

Claims

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;

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;

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:

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.