A method, wireless communication device and system for time synchronization

Abstract

The application discloses a time synchronization method, a wireless communication device and a system, and relates to the field of communication. The method comprises the following steps: a second wireless communication device receives a first time point and a first mark sent by a first wireless communication device; the second wireless communication device generates a second time point and a second mark; the second wireless communication device determines a third time point at which the second wireless communication device sends a pulse signal according to the first time point and a transmission time delay T1; the second wireless communication device calculates the transmission time delay T2 according to the second time point and the third time point; the second wireless communication device receives a fourth time point and an updated first mark; the second wireless communication device updates the time state of the second mark according to the updated first mark, adjusts the transmission time delay T1 according to the time state indicated by the updated second mark, and aligns the first time point and the fourth time point until the transmission time delay T1 is equal to the transmission time delay T2, so that the second wireless communication device completes the time synchronization of the first wireless communication device.

Description

Technical Field

[0001] This invention relates to the field of communications, and more specifically, to a time synchronization method, wireless communication device, and system. Background Technology

[0002] In wireless communication systems, precise time synchronization between transmitting and receiving devices is often required to achieve strict simultaneity. Wireless communication devices are highly efficient for technology verification and offer good implementation flexibility, leading to their widespread application in wireless system development. Analyzing the precise time transmission and reception methods of wireless communication devices is of great significance for technology development and hardware-in-the-loop simulation using wireless communication devices. Wireless communication devices are a type of wireless communication device based on the principles of Software-Defined Radio (SDR).

[0003] See Figure 1 The diagram shown illustrates the principle of prior art. Wireless communication devices typically connect to PCs via USB, RJ45, RS232, etc. A common method is for PCs to synchronize time using NTP, while the wireless communication device also synchronizes its time with the PC. The wireless communication device then transmits and receives signals according to the synchronized time.

[0004] The aforementioned existing technical solutions have poor time synchronization accuracy, which cannot meet the simulation and verification requirements of wireless communication equipment used in broadband systems in TDD mode. This is because using a PC for time synchronization introduces significant time errors. Firstly, while both NTP and PTP time synchronization offer high accuracy (down to the microsecond level), the time synchronization base point is on the PC. Time synchronization occurs between PCs, and then the PC time is synchronized to the wireless communication device. Due to the non-real-time nature of the PC operating system and the time transmission delay between the PC and the wireless communication device, significant errors, reaching the millisecond level, occur in the time transmission and reception of the wireless communication device. Secondly, the clock accuracy of a PC is only 10e-4 to 10e-5, and after a period of time synchronization, the accumulated error can reach the second level. Simulations of wireless systems such as 5G NR, LTE, and WLAN systems require time accuracy at the microsecond level; therefore, existing time synchronization solutions are significantly limited in application. Summary of the Invention

[0005] In view of this, the present invention provides a time synchronization method, wireless communication device and system for realizing time synchronization between wireless communication devices, avoiding the errors caused by using a PC for time synchronization, and also eliminating the errors caused by time synchronization between the PC and the wireless communication device.

[0006] The above-mentioned technical objective of the present invention is achieved through the following technical solution:

[0007] The first aspect of this application provides a time synchronization method, the method comprising:

[0008] The second wireless communication device receives a first timestamp and a first marker carried in the pulse signal sent by the first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind.

[0009] The second wireless communication device generates a second timestamp and a second marker, wherein the second timestamp indicates the second moment when the second wireless communication device receives the pulse signal, and the second marker indicates the time state of the first wireless communication device relative to the second wireless communication device.

[0010] The second wireless communication device determines the third timestamp for sending a pulse signal to the first wireless communication device based on the first time and the transmission delay T1, wherein the transmission delay T1 indicates the delay for the second wireless communication device to transmit to the first software communication device, and the third timestamp indicates the third time when the second wireless communication device sends the pulse signal.

[0011] The second wireless communication device calculates the transmission delay T2 from the first wireless communication device to the second software communication device based on the second time and the third time.

[0012] The second wireless communication device receives a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0013] The second wireless communication device updates the time state of the second marker according to the updated first marker, and adjusts the transmission delay T1 according to the time state indicated by the updated second marker until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes the time synchronization with the first wireless communication device.

[0014] In one implementation, the formula for calculating the third time point is t3 = t1 - T1, where t3 represents the third time point, t1 represents the first time point, and T1 represents the transmission delay from the second wireless communication device to the first software communication device.

[0015] A second aspect of this application also provides a time synchronization method, the method comprising:

[0016] The first wireless communication device sends a pulse signal carrying a first timestamp and a first marker to the second wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind.

[0017] The first wireless communication device receives a pulse signal carrying a third timestamp sent by the second wireless communication device. The third timestamp indicates the third moment when the second wireless communication device sends the pulse signal. The third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1. The transmission delay T1 indicates the delay when the second wireless communication device transmits the signal to the first software communication device.

[0018] The first wireless communication device sends a pulse signal carrying a fourth timestamp and an updated first marker to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first marker until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0019] In one implementation, the adjustment of the first marker is made by the first wireless communication device after comparing the time states of the fourth time point with those of the first time point. Specifically, the first wireless communication device compares the fourth time point with the first time point, detects whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp, and adjusts the first marker according to the detection result.

[0020] In one implementation, the first marker is adjusted cyclically until the calibration accuracy value is reached.

[0021] A third aspect of this application provides a time-synchronized wireless communication device, including a processor and a conversion module, wherein the processor and the conversion module establish a communication connection.

[0022] The conversion module is used to receive a first timestamp and a first marker carried by a pulse signal sent by a first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either a leading state or a lagging state.

[0023] A processor is configured to generate a second timestamp and a second marker, wherein the second timestamp indicates the second moment at which the second wireless communication device receives a pulse signal, and the second marker indicates the time state of the first wireless communication device relative to the second wireless communication device;

[0024] The processor is further configured to determine a third timestamp for the second wireless communication device to send a pulse signal to the first wireless communication device based on the first time and the transmission delay T1, wherein the transmission delay T1 indicates the delay for the second wireless communication device to transmit to the first software communication device, and the third timestamp indicates the third time when the second wireless communication device sends the pulse signal.

[0025] The processor is also configured to calculate the transmission delay T2 from the first wireless communication device to the second software communication device based on the second time point and the third time point;

[0026] The conversion module is also used to receive a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0027] The processor is also configured to update the time state of the second marker according to the updated first marker, and adjust the transmission delay T1 according to the time state indicated by the updated second marker until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2, and the second wireless communication device completes the time synchronization with the first wireless communication device.

[0028] In one implementation, the processor also uses the formula t3 = t1 - T1 for the calculation of the third time step, where t3 represents the third time step, t1 represents the first time step, and T1 represents the transmission delay from the second wireless communication device to the first software communication device.

[0029] A fourth aspect of this application provides a time-synchronized wireless communication device, including a processor and a conversion module, wherein the processor and the conversion module establish a communication connection.

[0030] The conversion module is used to send a pulse signal carrying a first timestamp and a first tag to the second wireless communication device. The first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first tag indicates the time state of the second wireless communication device relative to the first wireless communication device. The time state is either ahead or behind.

[0031] The conversion module is also used to receive a pulse signal carrying a third timestamp sent by the second wireless communication device, wherein the third timestamp indicates the third moment when the second wireless communication device sends the pulse signal, the third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1, and the transmission delay T1 indicates the delay when the second wireless communication device transmits to the first software communication device.

[0032] The conversion module is also used to send a pulse signal carrying a fourth timestamp and an updated first tag to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first tag until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first tag is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0033] The processor is used to communicate with the conversion module.

[0034] In one implementation, the processor is further configured to compare the fourth time point with the first time point, detect whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp, and adjust the first marker based on the detection result.

[0035] In one implementation, the processor is further configured to cyclically adjust the first mark until the adjustment reaches the calibration accuracy value.

[0036] The fifth aspect of this application also provides a time synchronization system, which includes a time-synchronized wireless communication device as described in the third aspect of this application and a time-synchronized wireless communication device as described in the fourth aspect of this application.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] This invention provides a time synchronization method in which a time synchronization base point is set between a first wireless communication device and a second wireless communication device. The first wireless communication device serves as the time base point, providing a reference pulse signal. The second wireless communication device also generates its own reference pulse signal, which is synchronized with the reference pulse of the first wireless communication device via a wireless signal. The time information of a first PC and a second PC are synchronized with the reference pulse signals of the first and second wireless communication devices, respectively. To ensure synchronization accuracy, the second wireless communication device synchronizes with the first wireless communication device at regular intervals. This achieves time synchronization between the first and second wireless communication devices, avoiding errors caused by using a PC for time synchronization and eliminating errors caused by further time synchronization between the PC and the wireless communication device. Attached Figure Description

[0039] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0040] Figure 1 A block diagram illustrating the principle of prior art time synchronization wireless communication devices and PCs is shown.

[0041] Figure 2 A schematic diagram of the structure of a time synchronization system provided by an embodiment of the present invention is shown;

[0042] Figure 3 A flowchart illustrating a time synchronization method provided by an embodiment of the present invention is shown;

[0043] Figure 4a A timeline of a pulse signal carrying a first timestamp is shown, provided by an embodiment of the present invention.

[0044] Figure 4b The diagram shows a timeline of a second wireless communication device receiving a pulse signal carrying a first timestamp, as provided in an embodiment of the present invention.

[0045] Figure 4c A timing diagram showing the transmission of a pulse signal carrying a third timestamp by a second wireless communication device according to an embodiment of the present invention is shown.

[0046] Figure 4d The diagram shows a timeline of a first wireless communication device receiving a pulse signal carrying a third timestamp, according to an embodiment of the present invention.

[0047] Figure 5 A block diagram illustrating the principle of time synchronization provided by an embodiment of the present invention is shown;

[0048] Figure 6The diagram shows a flowchart of another time synchronization method provided by an embodiment of the present invention. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0050] It should be noted that the terms "comprising" or "may include" used in the various embodiments of this application indicate the presence of the claimed function, operation, or element, and do not limit the addition of one or more functions, operations, or elements. Furthermore, terms such as "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0051] The technical solutions of this application embodiment can also be applied to various communication systems, such as: Global System for Mobile communication (GSM) system, Code Division Multiple Access (CDMA) system, Wideband Code Division Multiple Access (WCDMA) system, communication systems based on Orthogonal Frequency Division Multiplexing (OFDM) technology, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (FDD) system, LTE Time Division Duplex (TDD) system, Universal Mobile Telecommunication System (UMTS), Wireless Fidelity (WiFi) system, Worldwide Interoperability for Microwave Access (WiMAX) communication system, and Wireless Local Area Network (WLAN). Networks (WLAN) systems, Public Land Mobile Network (PLMN) networks, Vehicle-to-Everything (V2X) systems, 5G systems, future 6G systems or New Radio (NR) systems, optical transmission networks, wavelength division multiplexing (WDM) networks, etc.

[0052] It should be understood that the communication method in this application embodiment can be used in application scenarios that are sensitive to time synchronization or latency, such as autonomous or assisted driving, augmented reality (AR), virtual reality (VR), tactile internet, industrial control, smart grid, real-time games, process automation, factory automation, etc. This application embodiment does not limit this.

[0053] For example, in industrial control scenarios, controllers and actuators need to maintain time synchronization. The controller sends control signals to the actuator, instructing it to execute commands at a specified time. If the actuator and controller perceive time differently, i.e., they are out of sync, the actuator will execute commands at the wrong time, causing the task to fail.

[0054] To better understand the embodiments of this application, an application scenario used in these embodiments is described below. In communication networks, different base stations are required to synchronize their times, and the synchronization accuracy must be within the required range. The 1588V2 protocol is used to solve the time synchronization problem between base stations. The receiving device and the sending device interact through messages carrying timestamps, and the receiving device synchronizes its time with the sending device based on the timestamps. Specifically, the sending device sends a synchronization message at time t1, including a timestamp t1 indicating time t1 in the message; the receiving device receives the synchronization message at time t2, generates a timestamp t2 indicating time t2 locally, and extracts the timestamp t1 from the synchronization message; the receiving device sends a delay request message at time t3, generating a timestamp t3 indicating time t3 locally; the sending device receives the delay request message at time t4, generating a timestamp t4 indicating time t4 locally; the sending device includes the timestamp t4 in a delay response message and sends it to the receiving device; the receiving device extracts the timestamp t4 from the delay response message; the receiving device can calculate the time difference between itself and the sending device based on the obtained timestamps t1, t2, t3, and t4, and adjust its own time to achieve time synchronization with the sending device.

[0055] Correspondingly, there is a transmission delay between the sending device and the receiving device. When calculating the time deviation in the existing 1588V2 time synchronization, it is assumed that Delay1 = Delay2, the path delay from the sending device to the receiving device is equal to the path delay from the receiving device to the sending device, that is, the transmit and receive link delays are equal; then the time deviation calculation formula is further expressed as: N = [(t2-t1)-(t4-t3)] / 2.

[0056] Because the physical links and wavelengths used for transmitting and receiving timestamps often differ, achieving equal transmission and receiving link delays (Delay1 = Delay2) is difficult. If the path delay from the sending device to the receiving device is not equal to the path delay from the receiving device to the sending device (i.e., the transmission and receiving link delays are not equal), Delay1 ≠ Delay2, this will introduce synchronization errors into the time deviation. The synchronization error is M = (Delay1 - Delay2) / 2. To achieve high-precision time synchronization, the errors caused by unequal transmission and receiving link delays must be eliminated or reduced.

[0057] It should be understood that a timestamp is information indicating the time of the sender's or receiver's own clock when it is stamped. A timestamp can be a string or encoded information. The sender and receiver can be ports, modules, or network devices that require time synchronization. Synchronization messages, delay request messages, and delay response messages can be transmitted in the form of messages.

[0058] Based on the above, see Figure 1 The diagram illustrates the principle of existing technology. Wireless communication devices typically connect to PCs via USB, RJ45, RS232, etc. A common method for time synchronization based on the 1588V2 communication protocol is to use NTP time synchronization between PCs, while simultaneously synchronizing the wireless communication device with the PC's time. The wireless communication device then transmits and receives signals according to the synchronized time.

[0059] The aforementioned existing technical solutions have poor time synchronization accuracy, which cannot meet the simulation and verification requirements of wireless communication equipment applied to broadband systems in TDD mode. This is because using a PC for time synchronization introduces significant time errors. On the one hand, although both NTP and PTP time synchronization methods offer high accuracy (down to the microsecond level), the time synchronization base point is on the PC. Time synchronization occurs between PCs, and then the PC time is synchronized to the wireless communication device. Due to the non-real-time nature of the PC operating system and the time transmission delay between the PC and the wireless communication device, the time transmission and reception of the wireless communication device has a large error, reaching the millisecond level. On the other hand, the clock accuracy of a PC is only 10e-4 to 10e-5, and after a period of time synchronization, the accumulated error can reach the second level. Simulation of wireless systems such as 5G NR, LTE, and WLAN systems requires time accuracy at the microsecond level. Therefore, existing time synchronization solutions are significantly limited in their application to the simulation of 5G NR, LTE, and WLAN systems.

[0060] Figure 2This application illustrates a time synchronization system disclosed in an embodiment of the present application. Optionally, the first and second communication devices in the embodiments of the present application can be wavelength division multiplexing (WDM) devices, OTN devices, or other node units in WDM networks; the first wireless communication device in the embodiments of the present application can also be a wireless access network device or node (such as a base station (BS), a gNB in ​​a 5G mobile communication system, an evolved NodeB, a centralized unit (CU), or a distributed unit (DU)); the second wireless communication device can also be a terminal device, user equipment (UE), D2D (Device to Device) device, BS, gNB, eNB, CU, or DU; the first wireless communication device can be the aforementioned transmitting device, and the second wireless communication device can be the aforementioned receiving device.

[0061] like Figure 2 As shown, a time synchronization system includes a first communication device 20 and a second communication device 21, wherein the first communication device 20 and the second communication device 21 can be connected via a single-fiber bidirectional optical fiber. The second communication device 21 needs to adjust its own clock to achieve time synchronization with the first communication device 20. The signals transmitted by the first communication device 20 are all pulse signals of a first wavelength, and the signals transmitted by the second communication device 21 are all pulse signals of a second wavelength. For example, the first wavelength signal can be an optical signal with a wavelength of 1490nm based on the 1588 protocol, and the second wavelength signal can be an optical signal with a wavelength of 1510nm based on the 1588 protocol; or the first wavelength signal can also be an optical signal with a wavelength of 1506nm, and the second wavelength signal can also be an optical signal with a wavelength of 1514nm. The optical signals listed in this application are commonly used optical signals, but are not limited to these, and this embodiment will not elaborate further.

[0062] like Figure 3 As shown, a time synchronization method, applied to a second wireless communication device, includes:

[0063] S301, the second wireless communication device receives a first timestamp and a first marker carried in the pulse signal sent by the first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind.

[0064] In this embodiment, as Figure 4aAs shown, the first wireless communication device generates a reference pulse signal. Simultaneously with the generation of the reference pulse signal, a first timestamp a_pulseA is added to the pulse signal's time point, and the first wireless communication device sends this information to the second wireless communication device, along with a first flag a_flagA. The first flag a_flagA is used to mark the reference time (or the starting point of the first flag a_flagA can be used). The function of the first flag a_flagA is to inform the second wireless communication device whether its time state is ahead or behind that of the first wireless communication device.

[0065] S302, the second wireless communication device generates a second timestamp and a second mark, wherein the second timestamp indicates the second moment when the second wireless communication device receives the pulse signal, and the second mark indicates the time state of the first wireless communication device relative to the second wireless communication device.

[0066] In this embodiment, as Figure 4b As shown, the second wireless communication device receives the first timestamp a_pulseA and the first flag a_flagA carried by the pulse signal, and marks them as the second timestamp a_pulseB and the second flag a_flagB, respectively.

[0067] S303, the second wireless communication device determines a third timestamp for sending a pulse signal to the first wireless communication device based on the first time and the transmission delay T1, wherein the transmission delay T1 indicates the delay of the second wireless communication device transmitting to the first software communication device, and the third timestamp indicates the third time when the second wireless communication device sends the pulse signal.

[0068] In this embodiment, as Figure 4c As shown, the second wireless communication device generates a third timestamp b_pulseB for a pulse signal and sends this pulse signal to the first wireless communication device. Assuming the transmission delay from the second wireless communication device to the first wireless communication device is T1, the time of the third timestamp b_pulseB is the first time of the first timestamp a_pulseA minus T1. The value of T1 is adjusted according to whether the second flag a_flagB is ahead or behind, thereby dynamically adjusting the third time of the third timestamp b_pulseB.

[0069] like Figure 4d As shown, the first wireless communication device receives a pulse signal carrying a third timestamp b_pulseB sent by the second wireless communication device, and adds a fourth timestamp b_pulseA to the moment when the first wireless communication device receives the pulse signal carrying the third timestamp b_pulseB.

[0070] S304, the second wireless communication device calculates the transmission delay T2 from the first wireless communication device to the second software communication device based on the second time and the third time.

[0071] S305, the second wireless communication device receives a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0072] S306, the second wireless communication device updates the time state of the second mark according to the updated first mark, and adjusts the transmission delay T1 according to the time state indicated by the updated second mark until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes the time synchronization with the first wireless communication device.

[0073] In this embodiment, participants can Figure 5 As shown, the signal interaction transmission between the first wireless communication device and the second wireless communication device will return to step S301. The first wireless communication device compares the time indicated by the fourth timestamp b_pulseA with the time indicated by the first timestamp a_pulseA to determine whether the time state of the pulse signal is ahead or behind. Based on whether it is ahead or behind, the first flag a_flagA is re-marked. Subsequent steps S302 to T306 are executed cyclically, in each... Figure 4c During the signal processing steps shown, the second wireless communication device adjusts the transmission time marked by the third timestamp b_pulseB according to the second flag a_flagB, until the transmission time is as follows: Figure 4d As shown, this aligns the first time stamp a_pulseA at its first moment with the fourth time stamp b_pulseA at its fourth moment. Thus, subsequent actions... Figure 4b The second timestamp a_pulseB of the second wireless communication device shown is delayed by time T2 compared to the time of the third timestamp b_pulseB. The value of T2 is the transmission delay between the first wireless communication device and the second wireless communication device, which is equal to the transmission delay T1 described in step S303 of the embodiment.

[0074] By repeating steps S301-S306 of the method described in the above embodiments until the calibration value meets the requirements, the transmission delay between the first wireless communication device and the second wireless communication device can be accurately measured, thereby achieving accurate time synchronization between the first wireless communication device and the second wireless communication device platform.

[0075] Therefore, this invention proposes a time synchronization method for leading or lagging between software radio platforms (i.e., the first wireless communication device and the second wireless communication device). The time synchronization system adopts a loop structure for dynamic adjustment, which has the characteristics of simple implementation and high adjustment accuracy.

[0076] It should be understood that the time reference is set within the wireless communication device, not on the PC system. Wireless communication devices transmit data via channels (cable or wireless signals).

[0077] Optionally, the time state can be either a leading state or a lagging state. The fact that a time state can be leading or lagging is a well-known probability to those skilled in the art and will not be elaborated upon further.

[0078] Optionally, the formula for calculating the third time point is t3 = t1 - T1, where t3 represents the third time point, t1 represents the first time point, and T1 represents the transmission delay from the second wireless communication device to the first software communication device.

[0079] like Figure 6 As shown, a time synchronization method is applied to a first wireless communication device, comprising:

[0080] S601, the first wireless communication device sends a pulse signal carrying a first timestamp and a first marker to the second wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind.

[0081] S602, the first wireless communication device receives a pulse signal carrying a third timestamp sent by the second wireless communication device, wherein the third timestamp indicates the third moment when the second wireless communication device sends the pulse signal, the third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1, and the transmission delay T1 indicates the delay when the second wireless communication device transmits to the first software communication device.

[0082] S603, the first wireless communication device sends a pulse signal carrying a fourth timestamp and an updated first marker to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first marker until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0083] In one embodiment, the adjustment of the first marker is performed by the first wireless communication device after comparing the time states of the fourth time point with those of the first time point. Specifically, the first wireless communication device compares the fourth time point with the first time point, detects whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp, and adjusts the first marker based on the detection result.

[0084] In one embodiment, the first mark is adjusted cyclically until the adjustment reaches the calibration accuracy value.

[0085] Specifically, in this embodiment, the time state of the first flag is adjusted cyclically. The first wireless communication device compares the time indicated by the fourth timestamp b_pulseA with the time indicated by the first timestamp a_pulseA, detects whether it is ahead or behind, and marks the first flag a_flagA. Subsequent steps S301 to S306 are executed cyclically. In each step S305, the second wireless communication device adjusts the transmission time of the third timestamp b_pulseB according to the second flag a_flagB, until in step S306, the first time a_pulseA and the fourth time b_pulseA are aligned. Thus, the time T2 that a_pulseB received in subsequent step 2 lags behind b_pulseB is essentially equal to the previously described T1. It can be understood that the calibration accuracy value, i.e., T1 and T2, are equal.

[0086] Based on the time synchronization method for a second wireless communication device provided in the above embodiments, this embodiment provides a time-synchronized second wireless communication device, including a processor and a conversion module, wherein the processor and the conversion module establish a communication connection;

[0087] The conversion module is used to receive a first timestamp and a first marker carried by a pulse signal sent by a first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either a leading state or a lagging state.

[0088] A processor is configured to generate a second timestamp and a second marker, wherein the second timestamp indicates the second moment at which the second wireless communication device receives a pulse signal, and the second marker indicates the time state of the first wireless communication device relative to the second wireless communication device;

[0089] The processor is further configured to determine a third timestamp for the second wireless communication device to send a pulse signal to the first wireless communication device based on the first time and the transmission delay T1, wherein the transmission delay T1 indicates the delay for the second wireless communication device to transmit to the first software communication device, and the third timestamp indicates the third time when the second wireless communication device sends the pulse signal.

[0090] The processor is also configured to calculate the transmission delay T2 from the first wireless communication device to the second software communication device based on the second time point and the third time point;

[0091] The conversion module is also used to receive a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0092] The processor is also configured to update the time state of the second marker according to the updated first marker, and adjust the transmission delay T1 according to the time state indicated by the updated second marker until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2, and the second wireless communication device completes the time synchronization with the first wireless communication device.

[0093] Optionally, the processor also uses the formula t3 = t1 - T1 for the calculation of the third time step, where t3 represents the third time step, t1 represents the first time step, and T1 represents the transmission delay from the second wireless communication device to the first software communication device.

[0094] Based on the time synchronization method applied to a first wireless communication device according to the above embodiments, this embodiment provides a time synchronization first wireless communication device, including a processor and a conversion module, wherein the processor and the conversion module establish a communication connection;

[0095] The conversion module is used to send a pulse signal carrying a first timestamp and a first tag to the second wireless communication device. The first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first tag indicates the time state of the second wireless communication device relative to the first wireless communication device. The time state is either ahead or behind.

[0096] The conversion module is also used to receive a pulse signal carrying a third timestamp sent by the second wireless communication device, wherein the third timestamp indicates the third moment when the second wireless communication device sends the pulse signal, the third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1, and the transmission delay T1 indicates the delay when the second wireless communication device transmits to the first software communication device.

[0097] The conversion module is also used to send a pulse signal carrying a fourth timestamp and an updated first tag to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first tag until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first tag is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

[0098] The processor is used to communicate with the conversion module.

[0099] Optionally, the processor is also configured to compare the fourth time point with the first time point, detect whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp, and adjust the first marker according to the detection result.

[0100] Optionally, the processor is also configured to cyclically adjust the first mark until the adjustment reaches the calibration accuracy value.

[0101] The time synchronization method of this scheme based on the above example has high time calibration accuracy, which can reach the nanosecond level. Compared with the existing technology, the accuracy can be improved by more than 100 times.

[0102] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A time synchronization method, characterized in that, The methods include: The second wireless communication device receives a first timestamp and a first marker carried in the pulse signal sent by the first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind. The second wireless communication device generates a second timestamp and a second marker, wherein the second timestamp indicates the second moment when the second wireless communication device receives the pulse signal, and the second marker indicates the time state of the first wireless communication device relative to the second wireless communication device. The second wireless communication device determines a third timestamp for transmitting a pulse signal to the first wireless communication device based on the first time and the transmission delay T1. The transmission delay T1 indicates the delay in transmission from the second wireless communication device to the first wireless communication device, and the third timestamp indicates the third time when the second wireless communication device transmits the pulse signal. The value of the transmission delay T1 is adjusted according to the time status of the second marker. The second wireless communication device calculates the transmission delay T2 from the first wireless communication device to the second wireless communication device based on the second time and the third time. The second wireless communication device receives a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time. The second wireless communication device updates the time state of the second marker according to the updated first marker, and adjusts the transmission delay T1 according to the time state indicated by the updated second marker until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes the time synchronization with the first wireless communication device.

2. The time synchronization method according to claim 1, characterized in that, The formula for calculating the third time point is t3 = t1 - T1, where t3 represents the third time point, t1 represents the first time point, and T1 represents the transmission delay from the second wireless communication device to the first wireless communication device.

3. A time synchronization method, characterized in that, The methods include: The first wireless communication device sends a pulse signal carrying a first timestamp and a first marker to the second wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either ahead or behind. The first wireless communication device receives a pulse signal carrying a third timestamp sent by the second wireless communication device. The third timestamp indicates the third moment when the second wireless communication device sends the pulse signal. The third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1. The transmission delay T1 indicates the delay when the second wireless communication device transmits the signal to the first wireless communication device. The first wireless communication device sends a pulse signal carrying a fourth timestamp and an updated first marker to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first marker until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time.

4. The time synchronization method according to claim 3, characterized in that, The adjustment of the first marker is made by the first wireless communication device after comparing the time states of the fourth time point with those of the first time point. Specifically, the first wireless communication device compares the fourth time point with the first time point and detects whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp. The first marker is then adjusted based on the detection result.

5. The time synchronization method according to claim 4, characterized in that, The time state of the first marker is adjusted cyclically until the calibration accuracy value is reached.

6. A time-synchronized wireless communication device, characterized in that, This includes a processor and a conversion module, which establish a communication connection. The conversion module is used to receive a first timestamp and a first marker carried by a pulse signal sent by a first wireless communication device, wherein the first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first marker indicates the time state of the second wireless communication device relative to the first wireless communication device, and the time state is either a leading state or a lagging state. A processor is configured to generate a second timestamp and a second marker, wherein the second timestamp indicates the second moment at which the second wireless communication device receives a pulse signal, and the second marker indicates the time state of the first wireless communication device relative to the second wireless communication device; The processor is further configured to determine a third timestamp for the second wireless communication device to send a pulse signal to the first wireless communication device based on the first time and the transmission delay T1, wherein the transmission delay T1 indicates the delay of the second wireless communication device transmitting to the first wireless communication device, and the third timestamp indicates the third time when the second wireless communication device sends the pulse signal. The processor is also configured to calculate the transmission delay T2 from the first wireless communication device to the second wireless communication device based on the second time point and the third time point; The conversion module is also used to receive a fourth timestamp and an updated first marker carried by a pulse signal sent by the first wireless communication device after receiving the third time. The fourth timestamp indicates that the first wireless communication device received the fourth time marked by the third timestamp, and the adjustment of the first marker is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time. The processor is also configured to update the time state of the second marker according to the updated first marker, and adjust the transmission delay T1 according to the time state indicated by the updated second marker until the first time and the fourth time are aligned so that the transmission delay T1 is equal to the transmission delay T2, and the second wireless communication device completes the time synchronization with the first wireless communication device.

7. A time-synchronized wireless communication device, characterized in that, This includes a processor and a conversion module, which establish a communication connection. The conversion module is used to send a pulse signal carrying a first timestamp and a first tag to the second wireless communication device. The first timestamp indicates the first moment when the first wireless communication device sends the pulse signal, and the first tag indicates the time state of the second wireless communication device relative to the first wireless communication device. The time state is either ahead or behind. The conversion module is also used to receive a pulse signal carrying a third timestamp sent by the second wireless communication device, wherein the third timestamp indicates the third moment when the second wireless communication device sends the pulse signal, the third moment is calculated by the second wireless communication device based on the first moment and the transmission delay T1, and the transmission delay T1 indicates the delay when the second wireless communication device transmits to the first wireless communication device. The conversion module is also used to send a pulse signal carrying a fourth timestamp and an updated first tag to the second wireless communication device, so that the second wireless communication device adjusts the transmission delay T1 according to the time state indicated by the updated first tag until the first time and the fourth time are aligned, so that the transmission delay T1 is equal to the transmission delay T2. The second wireless communication device completes time synchronization with the first wireless communication device. The fourth timestamp indicates that the first wireless communication device receives the fourth time marked by the third timestamp. The adjustment of the first tag is made by the first wireless communication device after comparing the time state of the fourth time with that of the first time. The processor is used to communicate with the conversion module.

8. A time-synchronized wireless communication device according to claim 7, characterized in that, The processor is also used to compare the fourth time point with the first time point, detect whether the time state of the pulse signal carrying the third timestamp is ahead or behind the time state of the pulse signal carrying the first timestamp, and adjust the first marker according to the detection result.

9. A time-synchronized wireless communication device according to claim 8, characterized in that, The processor is also used to cyclically adjust the first mark until the adjustment reaches the calibration accuracy value.

10. A time synchronization system, characterized in that, The system includes a time-synchronized wireless communication device as described in claim 6 and a time-synchronized wireless communication device as described in any one of claims 7 to 9.

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