Wireless multi-node time-frequency synchronization method, device, electronic device and storage medium

Abstract

The present invention provides a wireless multi-node time and frequency synchronization method, device, electronic device, and storage medium. The method includes: receiving a clock signal cluster broadcast by a transmitting node; determining the period deviation between the clock signal of a local node and the clock signal of the transmitting node based on the measurement results of the clock signal cluster; when it is determined that the period deviation is less than a target threshold, measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node; performing a PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node. The present invention can achieve time and frequency synchronization between a transmitting node and multiple receiving nodes in a wireless manner, simplifies node expansion, has a high capacity limit, and does not need to consider issues such as the cost and routing design of wiring between nodes. At the same time, it can achieve sub-nanosecond time and frequency synchronization accuracy in the millimeter wave band.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to a wireless multi-node time and frequency synchronization method, device, electronic device and storage medium. Background Art

[0002] Multi-node network time-frequency synchronization is widely used in many fields, including data acquisition systems, blockchain data sharing, aerospace, geological exploration, etc. These fields have high requirements for the real-time performance of multi-node signals, so in-depth research on system synchronization is needed.

[0003] Currently, multiple time and frequency synchronization methods exist in multi-node networks. One approach is based on a sender-receiver mechanism, exemplified by the flooding clock synchronization protocol; the other is based on a receiver-receiver mechanism, exemplified by the reference broadcast synchronization protocol. However, the accuracy of both approaches decreases as the network diameter increases, making it difficult to achieve high-precision time and frequency synchronization and unable to meet the stringent navigation and positioning requirements of defense projects.

[0004] In the existing technology, although the synchronization accuracy of the optical fiber network time and frequency synchronization method is relatively high, the steps are complicated and the process is cumbersome when adding optical fiber synchronization nodes. At the same time, the cost of wiring between nodes and routing design issues also need to be considered.

[0005] Therefore, how to better achieve multi-node network time and frequency synchronization has become a technical problem that needs to be solved urgently in the industry. Summary of the Invention

[0006] The present invention provides a wireless multi-node time-frequency synchronization method, device, electronic device and storage medium, which are used to better achieve multi-node network time-frequency synchronization.

[0007] The present invention provides a wireless multi-node time-frequency synchronization method, comprising:

[0008] Receive the clock signal cluster broadcast by the transmitting node;

[0009] Determining a period deviation between a clock signal of a local node and a clock signal of the transmitting node based on a measurement result of the clock signal cluster;

[0010] When it is determined that the period deviation is less than a target threshold, measuring a phase deviation between a clock signal of the local node and a received clock signal of the transmitting node;

[0011] A PID algorithm is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0012] According to a wireless multi-node time and frequency synchronization method provided by the present invention, before measuring the phase deviation between the clock signal of the local node and the clock signal of the transmitting node when determining that the period deviation is less than a target threshold, the method further includes:

[0013] Step S1, when it is determined that the period deviation is not less than a target threshold, performing a PID algorithm calculation based on the period deviation, adjusting the crystal oscillator frequency of the local node according to the calculation result, and determining a corrected period of the clock signal of the local node;

[0014] Step S2, receiving the clock signal cluster broadcast by the transmitting node, and determining the period deviation between the correction period and the clock signal period of the transmitting node;

[0015] When it is determined that the period deviation is not less than the target threshold, steps S1 to S2 are performed until it is determined that the period deviation is less than the target threshold, so as to achieve frequency synchronization between the clock signal of the local node and the clock signal of the transmitting node.

[0016] According to a wireless multi-node time and frequency synchronization method provided by the present invention, determining the period deviation between the clock signal of the local node and the clock signal of the transmitting node based on the measurement result of the clock signal cluster includes:

[0017] Determining a period of a clock signal of the transmitting node based on a measurement result of the clock signal cluster;

[0018] When it is determined that the period of the clock signal of the local node is valid with the period of the clock signal of the transmitting node, a period deviation between the clock signal of the local node and the clock signal of the transmitting node is calculated.

[0019] According to a wireless multi-node time and frequency synchronization method provided by the present invention, the clock signal cluster includes multiple clock signals of the same period; the rising edge of the second pulse signal of the transmitting node is generated at the rising edge of the clock signal of the last period of the multiple clock signals of the same period; the PID algorithm is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node, including:

[0020] When it is determined that the phase deviation meets the preset threshold range, performing PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result;

[0021] Determining a distance between the adjusted clock signal of the local node and the transmitting node clock signal received by the local node;

[0022] Based on the spacing and the number of periods of the multiple clock signals with the same period, the phase of the second pulse signal of the local node is adjusted so that the second pulse signal of the local node is phase-synchronized with the second pulse signal of the transmitting node, so as to achieve time and frequency synchronization between the transmitting node and the local node.

[0023] According to a wireless multi-node time and frequency synchronization method provided by the present invention, the PID algorithm adopts an incremental PID algorithm; the PID algorithm calculation is performed based on the period deviation, the crystal oscillator frequency of the local node is adjusted according to the calculation result, and the correction period of the clock signal of the local node is determined, including:

[0024] The periodic deviation is used as an input of the incremental PID algorithm to perform operation to obtain a first target reference value;

[0025] Based on the first target reference value, the crystal oscillator frequency of the local node is adjusted to obtain a corrected period of the clock signal of the local node.

[0026] According to a wireless multi-node time and frequency synchronization method provided by the present invention, the PID algorithm adopts an incremental PID algorithm; the PID algorithm calculation is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result, including:

[0027] The phase deviation is used as an input of the incremental PID algorithm to perform calculation to obtain a second target reference value;

[0028] Adjusting the phase of the clock signal of the local node based on the second target reference value;

[0029] The second target reference amount is calculated by the following formula:

[0030] Δu2=K P (e(k)-e(k-1))+K I *e(k)+K D (e(k)-2e(k-1)+e(k-2));

[0031] Wherein, Δu2 represents the second target reference value; e(k) represents the phase deviation between the phase of the clock signal of the local node and the phase of the clock signal of the transmitting node at time k; K P Indicates the proportional magnification factor; K I Indicates the integral amplification factor; K D represents the differential amplification factor.

[0032] According to a wireless multi-node time and frequency synchronization method provided by the present invention, the local node is provided with a time-to-digital converter, which is used to measure the period and phase of the clock signal of the local node and the period and phase of the clock signal of the transmitting node.

[0033] The present invention also provides a wireless multi-node time-frequency synchronization device, comprising:

[0034] A receiving module, configured to receive the clock signal cluster broadcast by the transmitting node;

[0035] a processing module, configured to determine a period deviation between a clock signal of a local node and a clock signal of the transmitting node based on a measurement result of the clock signal cluster;

[0036] a measuring module, configured to measure a phase deviation between a clock signal of the local node and a received clock signal of the transmitting node when it is determined that the period deviation is less than a target threshold;

[0037] A synchronization module is used to perform PID algorithm calculation based on the phase deviation, and adjust the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0038] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the wireless multi-node time-frequency synchronization method as described above is implemented.

[0039] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the wireless multi-node time and frequency synchronization method as described above is implemented.

[0040] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned wireless multi-node time and frequency synchronization methods.

[0041] The wireless multi-node time and frequency synchronization method, device, electronic device and storage medium provided by the present invention utilize a transmitting node to transmit a cluster of equally spaced clock signals on a wireless channel, a local receiving node receives the clock signal cluster broadcast by the transmitting node, measures the period deviation between the clock signal of the local node and the clock signal of the transmitting node, and determines that the receiving node is frequency synchronized with the transmitting node when it is determined that the period deviation is less than a target threshold. The phase deviation between the receiving node clock signal and the received transmitting node clock signal is then measured, and a PID algorithm is used to synchronously adjust the phase of the receiving node clock signal according to the phase deviation, thereby achieving time and frequency synchronization between the transmitting node and multiple receiving nodes in a wireless manner. The node expansion is simple and the capacity upper limit is high. There is no need to consider issues such as the cost of wiring between nodes and the routing design. At the same time, sub-nanosecond time and frequency synchronization accuracy can be achieved in the millimeter wave band, which well meets the high index requirements of navigation and positioning in national defense projects. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0043] Figure 1 It is a flow chart of the wireless multi-node time-frequency synchronization method provided by the present invention;

[0044] Figure 2 It is a schematic diagram of the phase detection function of the receiving node in the wireless multi-node time and frequency synchronization method provided by the present invention;

[0045] Figure 3 This is one of the flow charts of frequency synchronization between transmitting and receiving nodes in the wireless multi-node time and frequency synchronization method provided by the present invention;

[0046] Figure 4 This is one of the flow charts of phase synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention;

[0047] Figure 5 This is the second flow chart of frequency synchronization between transmitting and receiving nodes in the wireless multi-node time and frequency synchronization method provided by the present invention;

[0048] Figure 6 This is the second flow chart of phase synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention;

[0049] Figure 7 It is a structural diagram of the wireless multi-node time-frequency synchronization device provided by the present invention;

[0050] Figure 8 It is a schematic diagram of the physical structure of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0051] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0052] The following combination Figures 1-8 The present invention describes a wireless multi-node time-frequency synchronization method, device, electronic device and storage medium.

[0053] Figure 1 FIG. 1 is a flow chart of the wireless multi-node time-frequency synchronization method provided by the present invention, as shown in FIG. Figure 1 As shown, in an embodiment of the present invention, a multi-node network includes a transmitting node and multiple receiving nodes. The execution subject of the method is each receiving node, and the method includes:

[0054] Step 110, receiving a clock signal cluster broadcast by a transmitting node;

[0055] Step 120 , determining a period deviation between a clock signal of the local node and a clock signal of the transmitting node based on the measurement result of the clock signal cluster;

[0056] Step 130 , when it is determined that the period deviation is less than the target threshold, measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node;

[0057] Step 140: Perform PID algorithm calculation based on the phase deviation, and adjust the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0058] Specifically, the clock signal cluster described in the embodiment of the present invention refers to a signal cluster composed of multiple continuous clock signals with the same period.

[0059] It can be understood that the local node described in the embodiment of the present invention can be any receiving node in a multi-node network.

[0060] The target threshold described in the embodiment of the present invention refers to a preset period deviation threshold, and the specific value range may be -500ns to 500ns.

[0061] In an embodiment of the present invention, in step 110, a multi-node wireless network of a transmitting node and multiple receiving nodes is established, and the transmitting node broadcasts an equally spaced clock signal cluster on a wireless channel, so that the local receiving node can receive the clock signal cluster broadcast by the transmitting node.

[0062] Based on the content of the above embodiment, as an optional embodiment, the local node is provided with a time-to-digital converter (TDC), which is used to measure the period and phase of the clock signal of the local node and the period and phase of the clock signal of the transmitting node.

[0063] In the prior art, TDC is generally used in the fields of laser ranging and ultrasonic velocity measurement. In an embodiment of the present invention, based on the period and phase of the clock signal measured by TDC, it is applied to the field of node time and frequency synchronization to accurately measure the period and phase of the clock signals of the local receiving node and the remote transmitting node.

[0064] In an embodiment of the present invention, by setting a TDC at a local node, the clock signals of the local node and the remote transmitting node can be measured by the same TDC on a single node, thereby avoiding the measurement differences of the same clock signal when using different TDCs, and facilitating improving the accuracy of time and frequency synchronization between the receiving node and the sending node.

[0065] Furthermore, in an embodiment of the present invention, in step 120, the clock signal cluster broadcast by the transmitting node can be measured through TDC to determine the clock signal period of the local node and the clock signal period of the transmitting node, thereby calculating the period deviation between the clock signals of the local node and the transmitting node.

[0066] In step 130, when it is determined through TDC that the period deviation is less than the target threshold, it can be indicated that the clock signals of the local node and the transmitting node have achieved frequency synchronization. Under this premise, the phase deviation between the local node clock signal and the received transmitting node clock signal is measured using TDC.

[0067] It should be noted that in the embodiments of the present invention, due to the minimum time interval for TDC testing, it is necessary to increase the interval measurement range to implement the phase detection function. The phase detection function presupposes that the receiving node has achieved frequency synchronization with the transmitting node, that is, it determines that the period deviation between the clock signals of the local node and the transmitting node is less than the target threshold.

[0068] It should also be noted that after achieving time-frequency synchronization, the time accuracy index of multiple nodes is relative to the transmitting node, and is not synchronized with Universal Time Coordinated (UTC).

[0069] Figure 2 Schematic diagram of the phase detection function of the receiving node in the wireless multi-node time-frequency synchronization method provided by the present invention, as shown in FIG. Figure 2 As shown, in this embodiment, the clock signal cluster transmitted by the transmitting node is a clock signal with n (e.g., n=10) cycles continuously transmitted. The received signal at the receiving node is the clock signal of the transmitting node received by the receiving node, and the local oscillator signal at the receiving node is the clock signal generated by the crystal oscillator of the receiving node. The phase difference t1 between the local oscillator signal of the receiving node and the received signal at the receiving node satisfies t1=t2-(n-1)*T, where T represents the period of the local local oscillator signal of the receiving node. Using a TDC, t2 can be measured, from which the phase difference t1 between the local oscillator signal of the receiving node and the received signal at the receiving node can be calculated.

[0070] Furthermore, in an embodiment of the present invention, in step 140, a PID algorithm is calculated based on the above-mentioned phase deviation to determine an adjustment control amount to adjust the clock signal phase of the local node, control the clock signal phase of the local node to be synchronized with the clock signal phase of the transmitting node, and control the second pulse signal phase of the local node to be synchronized with the second pulse signal phase of the transmitting node, thereby achieving time and frequency synchronization between the transmitting node and the local node.

[0071] In an embodiment of the present invention, a method for measuring clock period based on TDC is used to adjust the frequency of the crystal oscillator of the receiving node so that the period difference between multiple receiving nodes and the transmitting node approaches zero, thereby achieving frequency synchronization between wireless nodes; a method for measuring clock phase difference based on TDC is used to adjust the phase of the crystal oscillator of the receiving node so that the phase of the local oscillator signal and the second pulse signal between multiple receiving nodes is aligned, thereby achieving phase synchronization between multiple wireless nodes.

[0072] The method of the present invention does not rely on ephemeris calculations by signal base stations, satellites, or terminals, and can achieve time-frequency synchronization under certain conditions based solely on multiple nodes. Furthermore, compared to fiber-optic time-frequency transmission synchronization technology, the method of the present invention utilizes wireless channels to transmit clock signals, so the clock period does not vary with the distance between nodes, thus maintaining the accuracy of time-frequency synchronization. Furthermore, it can support time-frequency synchronization between multiple dynamic nodes.

[0073] The wireless multi-node time and frequency synchronization method of the embodiment of the present invention utilizes a transmitting node to transmit a cluster of equally spaced clock signals on a wireless channel, and a local receiving node receives the clock signal cluster broadcast by the transmitting node, measures the period deviation between the clock signal of the local node and the clock signal of the transmitting node, and determines that the receiving node is frequency synchronized with the transmitting node when it is determined that the period deviation is less than a target threshold. Then, the phase deviation between the receiving node clock signal and the received transmitting node clock signal is measured, and a PID algorithm is used to synchronously adjust the phase of the receiving node clock signal according to the phase deviation, thereby realizing time and frequency synchronization between the transmitting node and multiple receiving nodes in a wireless manner. The node expansion is simple and the capacity upper limit is high. There is no need to consider issues such as the cost of wiring between nodes and the routing design. At the same time, sub-nanosecond time and frequency synchronization accuracy can be achieved in the millimeter wave band, which well meets the high index requirements of navigation and positioning in national defense projects.

[0074] Based on the content of the above embodiment, as an optional embodiment, before measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node when determining that the period deviation is less than the target threshold, the method further includes:

[0075] Step S1, when it is determined that the period deviation is not less than the target threshold, performing PID algorithm calculation based on the period deviation, adjusting the crystal oscillator frequency of the local node according to the calculation result, and determining the correction period of the clock signal of the local node;

[0076] Step S2, receiving the clock signal cluster broadcast by the transmitting node, and determining the period deviation between the correction period and the clock signal period of the transmitting node;

[0077] When it is determined that the period deviation is not less than the target threshold, steps S1 to S2 are performed until it is determined that the period deviation is less than the target threshold, so as to achieve frequency synchronization between the clock signal of the local node and the clock signal of the transmitting node.

[0078] Specifically, the correction period described in the embodiment of the present invention refers to the period of the clock signal output by the local node after the crystal oscillator frequency of the local node is corrected and adjusted by performing PID calculation based on the above period deviation.

[0079] In an embodiment of the present invention, in step S1, when it is determined that the period deviation between the clock signals of the local node and the transmitting node is not less than the target threshold, it indicates that the frequencies of the local node and the transmitting node are not synchronized and need to be adjusted.

[0080] In an embodiment of the present invention, a PID algorithm is used to perform PID calculation based on the period deviation. After adjusting the crystal oscillator frequency of the local node according to the calculation result, the corrected period of the clock signal of the local node is determined.

[0081] Based on the content of the above embodiment, as an optional embodiment, the PID algorithm adopts an incremental PID algorithm; the PID algorithm calculation is performed based on the period deviation, and the crystal oscillator frequency of the local node is adjusted according to the calculation result to determine the correction period of the clock signal of the local node, including:

[0082] The periodic deviation is used as the input of the incremental PID algorithm to calculate and obtain the first target reference value;

[0083] Based on the first target reference value, the crystal oscillator frequency of the local node is adjusted to obtain a corrected period of the clock signal of the local node.

[0084] Specifically, the first target reference quantity described in the embodiment of the present invention refers to the control quantity output by PID operation based on the deviation of the signal period between the local node and the transmitting node, which is used to adjust the signal period between the local node and the transmitting node to be consistent to achieve the purpose of frequency synchronization.

[0085] It should be noted that the PID algorithm consists of three parts: proportional control, integral control and differential control. The PID algorithm includes position PID algorithm and incremental PID algorithm.

[0086] Among them, the input and output of the position PID algorithm have the following relationship:

[0087]

[0088] Where, e(t) represents input; u(t) represents output; K P ' represents the proportional magnification factor; K I ' represents the integral amplification coefficient; K D ′ represents the differential amplification coefficient. These three parameters are constants determined through debugging.

[0089] Since the position-type PID algorithm requires all previous deviation signals, while the incremental PID algorithm only requires one incremental signal, it can be seen that the calculation of the position-type PID algorithm is cumbersome; at the same time, the output of the position-type PID control is related to the entire past state and uses the accumulated value of the error, while the output of the incremental PID algorithm is only related to the error between the current beat and the previous two beats. In comparison, the cumulative error of the position-type PID control is relatively larger.

[0090] Therefore, in an embodiment of the present invention, an incremental PID algorithm is adopted as the PID algorithm, and the period deviation of the clock signals of the local node and the transmitting node is used as the input of the incremental PID algorithm to perform operation and calculate the first target reference value.

[0091] Optionally, the first target reference amount is calculated using the following formula:

[0092] Δu1=K P1 (e′(k)-e′(k-1))+K I1 *e′(k)+K D1 (e′(k)-2e′(k-1)+e′(k-2));

[0093] Wherein, Δu1 represents the first target reference value; e′(k) represents the period deviation between the period of the clock signal of the local node and the clock signal of the transmitting node at time k; K P1 Indicates the proportional magnification factor; K I1 Indicates the integral amplification factor; K D1 represents the differential amplification factor.

[0094] The above formula is the specific relationship between the input and output of the incremental PID algorithm, where the first target reference quantity Δu1 is the output and e′(k) is the input.

[0095] Furthermore, based on the first target reference quantity, the crystal oscillator frequency of the local node is adjusted to obtain the corrected period of the clock signal generated by the local node after adjustment. The input of the PID algorithm is the period deviation between the local node clock signal and the transmitting node clock signal. Therefore, as long as there is a period deviation between the two, the PID algorithm will automatically calculate a target reference quantity. Only when the period deviation between the two is 0 will the output of the PID algorithm also be 0. This shows that the automatic feedback mechanism of the PID algorithm can automatically output the target reference quantity and determine the required control quantity, which is used to adjust the crystal oscillator frequency of the local dynamic node so that the frequency of the local node clock signal and the transmitting node clock signal reach the same frequency, achieving frequency synchronization.

[0096] The method of the embodiment of the present invention calculates the adjustment control quantity by adopting an incremental PID algorithm, which has a small amount of calculation and can quickly adjust the crystal oscillator frequency of the local node, thereby effectively improving the efficiency of frequency synchronization between the transmitting node and each receiving node.

[0097] Furthermore, in step S2, the receiving node continues to receive the clock signal cluster broadcast by the transmitting node, and determines the period deviation between the correction period and the clock signal period of the transmitting node, and again uses the target threshold to judge the period deviation. If the period deviation is still not less than the target threshold, steps S1 to S2 are repeated until it is determined that the period deviation between the clock signals of the local node and the transmitting node is less than the target threshold, thereby ensuring that the clock signal of the local node is frequency synchronized with the clock signal of the transmitting node.

[0098] The method of the embodiment of the present invention can effectively achieve frequency synchronization between the local node and the transmitting node by performing signal frequency synchronization before achieving phase synchronization of the clock signals of the local node and the transmitting node, using a logical loop judgment method, facilitating subsequent phase synchronization operations between the local node and the transmitting node, and is beneficial to improving the accuracy of time and frequency synchronization between the local node and the transmitting node.

[0099] Figure 3 This is one of the flow charts of frequency synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention, such as Figure 3 As shown, in an embodiment of the present invention, after obtaining the clock signal period t1 of the transmitting node and the clock signal period t2 of the receiving node, the period deviation △t between the two can be calculated, and then the PID algorithm is used to calculate the period deviation △t of the clock signal periods of the receiving node and the transmitting node as the input of the PID algorithm to obtain the first target reference value.

[0100] A correction voltage (digital quantity) is then calculated based on the current operating voltage of the local receiving node's voltage-controlled oven-controlled crystal oscillator (VC-OCXO) and the first target reference. This correction voltage is then input to a digital-to-analog converter (DAC) via the SPI interface. The DAC converts the correction voltage into a corresponding analog voltage, V0, and outputs it as the voltage control input signal for the local receiving node's VC-OCXO. This adjusts the output frequency of the receiving node's VC-OCXO. This data processing is repeated to achieve real-time frequency synchronization between the transmitting node and each receiving node.

[0101] Based on the content of the above embodiment, as an optional embodiment, determining the period deviation between the clock signal of the local node and the clock signal of the transmitting node based on the measurement result of the clock signal cluster includes:

[0102] Determining a period of a clock signal of a transmitting node based on a measurement result of the clock signal cluster;

[0103] When it is determined that the period of the clock signal of the local node is valid with the period of the clock signal of the transmitting node, a period deviation between the clock signal of the local node and the clock signal of the transmitting node is calculated.

[0104] Specifically, in an embodiment of the present invention, the period of the clock signal is preset within a valid value range, specifically, 100ms-500ns to 100ms+500ns. That is, the period of the local node's clock signal and the period of the transmitting node's clock signal are measured using a TDC. If the measured period values ​​are within the valid value range, the measured period is deemed valid; otherwise, the measured period is deemed invalid.

[0105] Furthermore, only when it is determined that the period of the clock signal of the local node is valid with the period of the clock signal of the transmitting node, the period deviation between the clock signal of the local node and the clock signal of the transmitting node is calculated to ensure the accuracy of the calculated value.

[0106] The method of the embodiment of the present invention further ensures the accuracy and validity of the TDC measurement result by introducing a period value validity determination mechanism, and provides reliable calculation data for subsequent inter-node frequency synchronization adjustment.

[0107] Based on the content of the above embodiment, as an optional embodiment, the clock signal cluster includes multiple clock signals of the same period; the rising edge of the second pulse signal of the transmitting node is generated at the rising edge of the clock signal of the last period of the multiple clock signals of the same period; PID algorithm calculation is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node, including:

[0108] If the phase deviation is determined to be within a preset threshold range, a PID algorithm is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result;

[0109] determining a distance between the adjusted clock signal of the local node and the clock signal of the transmitting node received by the local node;

[0110] Based on the spacing and the number of cycles of multiple clock signals with the same cycle, the phase of the second pulse signal of the local node is adjusted to synchronize the phase of the second pulse signal of the local node with the second pulse signal of the transmitting node, so as to achieve time and frequency synchronization between the transmitting node and the local node.

[0111] Specifically, the preset threshold range described in the embodiments of the present invention is used to determine whether the phase deviation between the clock signals of the local node and the transmitting node measured by TDC is valid. If the phase deviation is within the preset threshold range, the measurement is considered valid; otherwise, it is considered invalid. In the embodiments of the present invention, the preset threshold range can be between -180° and 180°.

[0112] The spacing described in the embodiment of the present invention refers to the spacing between the phase-adjusted clock signal of the local node and the clock signal of the transmitting node received by the local node, which is generally an integer multiple of the unit cycle wavelength of the clock signal.

[0113] In an embodiment of the present invention, a clock signal cluster may include multiple clock signals of the same period, and the rising edge of the pulse-per-second signal of the transmitting node is generated at the rising edge of the clock signal of the last period of the multiple clock signals of the same period. For example, if the clock signal cluster transmitted by the transmitting node includes 10 clock signals of the same period, the rising edge of the pulse-per-second signal generated by the transmitting node is generated at the rising edge of the clock signal of the 10th period.

[0114] Furthermore, in an embodiment of the present invention, if it is determined that the phase deviation between the local node's clock signal and the transmitting node's clock signal falls within a preset threshold range, such as -180° to 180°, a PID algorithm can be performed based on the phase deviation to adjust the phase of the local node's clock signal, thereby achieving phase synchronization of the clock signals between the local node and the transmitting node. Furthermore, the distance between the phase-adjusted local node's clock signal and the locally received transmitting node's clock signal is calculated. If the local node receives the clock signal only after the transmitting node has transmitted three cycles of the clock signal, the distance between the local node's clock signal and the received transmitting node's clock signal can be determined to be three times the wavelength of the transmission frequency.

[0115] Furthermore, in an embodiment of the present invention, the phase of the local node's clock signal is adjusted based on the aforementioned spacing and the number of cycles of multiple clock signals with the same period. In this case, after achieving frequency synchronization, the local node performs phase discrimination between the received clock signal and the local oscillator signal, and uses the FPGA's Modular Clock Manager (MMCM) to perform phase shifting operations to achieve phase synchronization between the local node's clock signal and the received clock signal. In this case, after the aforementioned phase adjustment, the spacing between the local node's and the transmitting node's clock signals is an integer m times the wavelength of the transmission frequency. The transmitting node broadcasts a cluster of equally spaced clock signals, which can include n clock cycles, and generates a rising edge of a pulse-per-second signal at the rising edge of the nth clock signal. Therefore, after receiving the cluster of equally spaced clock signals, the local node can generate a rising edge of a pulse-per-second signal at the rising edge of the nmth clock signal, thereby achieving phase synchronization between the pulse-per-second signals of the receiving and transmitting nodes. Because phase synchronization is performed based on frequency synchronization between the local node and the transmitting node, time-frequency synchronization between the transmitting node and the local node is also achieved.

[0116] Figure 4 This is one of the flow charts of phase synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention, such as Figure 4As shown, in this embodiment, the transmitting node continuously sends 10 cycles of clock signals at equal intervals. Since the phase synchronization of the second pulse signal is premised on the receiving node having achieved the same frequency and phase as the transmitting node's clock signal, in calibration mode, the spacing between the receiving node's local oscillator signal and the receiving node's received signal (the received transmitting node's clock signal) is three times the frequency wavelength. The rising edge of the second pulse signal of the transmitting node occurs at every 10th rising edge, while the rising edge of the second pulse signal of the receiving node occurs at every 7th rising edge. This compensates for the signal propagation time caused by distance and effectively achieves phase synchronization of the second pulse signals between the receiving node and the transmitting node.

[0117] The method of the embodiment of the present invention adopts the PID algorithm to adjust the phase of the clock signal of the local node based on the phase deviation, thereby achieving the same frequency and phase function as the frequency signal of the transmitting node, and then adjusting the phase of the second pulse signal of the local node to synchronize the phase of the second pulse signal of the local node with the second pulse signal of the transmitting node. This can effectively achieve time and frequency synchronization between the transmitting node and the local node, and can achieve sub-nanosecond time and frequency synchronization accuracy in the millimeter wave band.

[0118] Based on the content of the above embodiment, as an optional embodiment, the PID algorithm adopts an incremental PID algorithm; the PID algorithm calculation is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result, including:

[0119] The phase deviation is used as the input of the incremental PID algorithm to calculate and obtain the second target reference value;

[0120] Adjusting the phase of the clock signal of the local node based on the second target reference quantity;

[0121] The second target reference amount is calculated using the following formula:

[0122] Δu2=K P (e(k)-e(k-1))+K I *e(k)+K D (e(k)-2e(k-1)+e(k-2));

[0123] Wherein, Δu2 represents the second target reference value; e(k) represents the phase deviation between the phase of the clock signal of the local node and the phase of the clock signal of the transmitting node at time k; K P Indicates the proportional magnification factor; K I Indicates the integral amplification factor; K D represents the differential amplification factor.

[0124] Specifically, the second target reference quantity described in the embodiment of the present invention refers to the control quantity output by PID operation based on the phase deviation of the clock signal between the local node and the transmitting node, which is used to adjust the phase of the signal between the local node and the transmitting node to achieve the purpose of phase synchronization.

[0125] Similarly, since the output of the incremental PID algorithm is only related to the error between the current beat and the previous two beats, compared to the position-based PID algorithm, the cumulative error is relatively smaller and the calculation accuracy is more advantageous. Therefore, in an embodiment of the present invention, an incremental PID algorithm is adopted as the PID algorithm, and the phase deviation of the clock signals of the local node and the transmitting node is used as the input of the incremental PID algorithm to calculate the second target reference quantity.

[0126] Optionally, the second target reference amount Δu2 can be calculated using the above formula, where the second target reference amount Δu2 is the output and e(k) is the input.

[0127] Furthermore, based on the second target reference quantity, the phase of the local node's clock signal is adjusted so that the adjusted clock signal of the local node is phase-synchronized with the clock signal of the transmitting node. Similarly, at this time, the input of the PID algorithm is the phase deviation between the local node clock signal and the transmitting node clock signal. As long as there is a phase deviation between the two, the PID algorithm will automatically calculate a target reference quantity. Only when the period deviation between the two is 0 will the output of the PID algorithm also be 0. The automatic feedback mechanism of the PID algorithm can automatically output the target reference quantity and determine the required control quantity to adjust the phase of the local node's clock signal, so that the phase of the local node's clock signal and the transmitting node's clock signal are consistent, and also promote the phase of the local node's second pulse signal and the second pulse signal of the transmitting node to be consistent, achieving phase synchronization.

[0128] The method of the embodiment of the present invention calculates the adjustment control quantity by adopting an incremental PID algorithm with a small amount of calculation. It can quickly adjust the phase of the local node clock signal to achieve phase synchronization between the transmitting node and each receiving node, thereby effectively improving the efficiency of phase synchronization between the transmitting node and each receiving node.

[0129] Figure 5 This is the second flow chart of frequency synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention. Figure 5 As shown, it is the software system program execution process, which can be compared with Figure 3 After the software system is powered on, the system is initialized, including clock, interface, and printer port initialization. Wait 10 minutes for the voltage-controlled oven-controlled crystal oscillator (VC-OCXO) to stabilize.

[0130] Furthermore, in an embodiment of the present invention, a transmitting node broadcasts a clock signal cluster over a wireless channel to each receiving node in the network. Each receiving node then measures the period of the transmitting node's clock signal and the period of the local node (receiving node)'s clock signal by invoking a locally configured TDC. The valid period values ​​of the transmitting and receiving node's clock signals are then determined. If the period values ​​are invalid, the TDC measurement is repeated. If the period values ​​are valid, the period deviation between the receiving and transmitting node's clock signals is calculated.

[0131] Further, it is determined whether the period deviation is less than a threshold, i.e., the aforementioned target threshold. If so, the frequency synchronization completion flag is set, and then the process jumps to the step of TDC measuring the period of the clock signals of the transmitting node and the receiving node to determine whether the local node and the transmitting node achieve real-time frequency synchronization; otherwise, the local node performs PID control operation based on the period deviation to calculate the first target reference quantity, and then calculates the correction voltage of the digital quantity based on the current operating voltage of the local node VC-OCXO and the target reference quantity, and then inputs the correction voltage into the digital-to-analog converter DAC through the SPI interface. The DAC converts the correction voltage into the corresponding analog voltage V0 and outputs it as the voltage control input signal of the local node VC-OCXO, thereby adjusting the voltage-controlled frequency of the local node VC-OCXO and changing the period of the local node clock signal.

[0132] Next, the TDC measures the clock signal periods of the transmitting and receiving nodes. The deviation between the clock signal period after adjusting the VC-OCXO frequency at the local node and the transmitting node's clock signal period is determined. This deviation is kept below a target threshold, and the frequency synchronization complete flag is set. This process is repeated repeatedly to dynamically synchronize the frequencies of each receiving and transmitting node in real time.

[0133] Figure 6 This is the second flow chart of phase synchronization between transmitting and receiving nodes in the wireless multi-node time-frequency synchronization method provided by the present invention, such as Figure 6As shown in FIG, it is the execution flow of the software system program. After the software system is powered on, the system is initialized first, and then the local node determines whether the frequency synchronization is valid based on the setting of the frequency synchronization completion flag, that is, whether the frequency synchronization between the local node and the transmitting node has been achieved. If it has been achieved, the TDC is used to identify and measure the phase of the received transmitting node clock signal and the local oscillator signal, and the phase deviation between the two signals is measured. Based on whether the phase difference is within the preset threshold range, it is determined whether the phase deviation measurement result is valid. If not, the phase difference is measured again; if the phase difference measurement result is valid, a PID control operation is performed according to the measured phase deviation to adjust the output signal phase of the local node VC-OCXO, thereby changing the phase of the receiving node local oscillator signal and the second pulse signal (PPS) phase, and realizing the phase synchronization function between the local node second pulse signal and the transmitting node second pulse signal.

[0134] Next, by jumping to the step of measuring the phase of the clock signals of the transmitting node and the receiving node by TDC and cyclically executing the above phase synchronization procedure, the phase synchronization between each receiving node and the transmitting node can be realized dynamically in real time.

[0135] The wireless multi-node time and frequency synchronization device provided by the present invention is described below. The wireless multi-node time and frequency synchronization device described below and the wireless multi-node time and frequency synchronization method described above can be referenced to each other.

[0136] Figure 7 This is a schematic diagram of the structure of the wireless multi-node time-frequency synchronization device provided by the present invention. Figure 7 Shown, including:

[0137] The receiving module 710 is configured to receive a clock signal cluster broadcast by a transmitting node;

[0138] A processing module 720 is configured to determine a period deviation between a clock signal of a local node and a clock signal of a transmitting node based on a measurement result of the clock signal cluster;

[0139] a measurement module 730 configured to measure a phase deviation between a clock signal of a local node and a received clock signal of a transmitting node when determining that the period deviation is less than a target threshold;

[0140] The synchronization module 740 is configured to perform PID algorithm calculation based on the phase deviation and adjust the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0141] The wireless multi-node time and frequency synchronization device described in this embodiment can be used to execute the above-mentioned wireless multi-node time and frequency synchronization method embodiment. Its principles and technical effects are similar and will not be repeated here.

[0142] The wireless multi-node time and frequency synchronization device of the embodiment of the present invention utilizes a transmitting node to transmit a cluster of equally spaced clock signals on a wireless channel, and a local receiving node receives the clock signal cluster broadcast by the transmitting node, measures the period deviation between the clock signal of the local node and the clock signal of the transmitting node, and determines that the receiving node is frequency synchronized with the transmitting node when it is determined that the period deviation is less than the target threshold. Then, the phase deviation between the clock signal of the receiving node and the received clock signal of the transmitting node is measured, and a PID algorithm is used to synchronously adjust the phase of the clock signal of the receiving node according to the phase deviation, thereby realizing time and frequency synchronization between the transmitting node and multiple receiving nodes in a wireless manner. The node expansion is simple and the capacity upper limit is high. There is no need to consider issues such as the cost of wiring between nodes and the routing design. At the same time, sub-nanosecond time and frequency synchronization accuracy can be achieved in the millimeter wave band, which well meets the high index requirements of navigation and positioning in national defense projects.

[0143] Figure 8 This is a schematic diagram of the physical structure of the electronic device provided by the present invention, such as Figure 8 As shown, the electronic device may include: a processor 810, a communication interface 820, a memory 830, and a communication bus 840, wherein the processor 810, the communication interface 820, and the memory 830 communicate with each other through the communication bus 840. The processor 810 can call the logic instructions in the memory 830 to execute the wireless multi-node time and frequency synchronization method provided by the above methods, which includes: receiving a clock signal cluster broadcast by a transmitting node; determining the period deviation between the clock signal of the local node and the clock signal of the transmitting node based on the measurement result of the clock signal cluster; when it is determined that the period deviation is less than a target threshold, measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node; performing PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0144] In addition, the logic instructions in the above-mentioned memory 830 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0145] On the other hand, the present invention also provides a computer program product, which includes a computer program, which can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the wireless multi-node time and frequency synchronization method provided by the above methods, which includes: receiving a clock signal cluster broadcast by a transmitting node; determining the periodic deviation between the clock signal of a local node and the clock signal of the transmitting node based on the measurement results of the clock signal cluster; when it is determined that the periodic deviation is less than a target threshold, measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node; performing PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0146] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the wireless multi-node time and frequency synchronization method provided by the above-mentioned methods, the method comprising: receiving a clock signal cluster broadcast by a transmitting node; determining a periodic deviation between a clock signal of a local node and a clock signal of the transmitting node based on a measurement result of the clock signal cluster; when it is determined that the periodic deviation is less than a target threshold, measuring a phase deviation between the clock signal of the local node and the received clock signal of the transmitting node; performing a PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node.

[0147] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0148] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A wireless multi-node time-frequency synchronization method, characterized in that: include: Receive the clock signal cluster broadcast by the transmitting node; Determining a period deviation between a clock signal of a local node and a clock signal of the transmitting node based on a measurement result of the clock signal cluster; When it is determined that the period deviation is less than a target threshold, measuring a phase deviation between a clock signal of the local node and a received clock signal of the transmitting node; Performing a PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node; Before measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node when determining that the period deviation is less than a target threshold, the method further includes: Step S1, when it is determined that the period deviation is not less than a target threshold, performing a PID algorithm calculation based on the period deviation, adjusting the crystal oscillator frequency of the local node according to the calculation result, and determining a corrected period of the clock signal of the local node; Step S2, receiving the clock signal cluster broadcast by the transmitting node, and determining the period deviation between the correction period and the clock signal period of the transmitting node; When it is determined that the period deviation is not less than the target threshold, steps S1 to S2 are performed until it is determined that the period deviation is less than the target threshold, so as to achieve frequency synchronization between the clock signal of the local node and the clock signal of the transmitting node.

2. The wireless multi-node time-frequency synchronization method according to claim 1, characterized in that: The determining, based on the measurement result of the clock signal cluster, a period deviation between the clock signal of the local node and the clock signal of the transmitting node includes: Determining a period of a clock signal of the transmitting node based on a measurement result of the clock signal cluster; When it is determined that the period of the clock signal of the local node is valid with the period of the clock signal of the transmitting node, a period deviation between the clock signal of the local node and the clock signal of the transmitting node is calculated.

3. The wireless multi-node time-frequency synchronization method according to claim 1, wherein: The clock signal cluster includes multiple clock signals of the same period; the rising edge of the second pulse signal of the transmitting node is generated at the rising edge of the clock signal of the last period among the multiple clock signals of the same period; the PID algorithm is performed based on the phase deviation, and the phase of the clock signal of the local node is adjusted according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node, including: When it is determined that the phase deviation meets the preset threshold range, performing PID algorithm calculation based on the phase deviation, and adjusting the phase of the clock signal of the local node according to the calculation result; Determining a distance between the adjusted clock signal of the local node and the transmitting node clock signal received by the local node; Based on the spacing and the number of periods of the multiple clock signals with the same period, the phase of the second pulse signal of the local node is adjusted so that the second pulse signal of the local node is phase-synchronized with the second pulse signal of the transmitting node, so as to achieve time and frequency synchronization between the transmitting node and the local node.

4. The wireless multi-node time-frequency synchronization method according to claim 1, wherein: The PID algorithm adopts an incremental PID algorithm; performing PID algorithm calculation based on the period deviation, adjusting the crystal oscillator frequency of the local node according to the calculation result, and determining the correction period of the clock signal of the local node include: The periodic deviation is used as an input of the incremental PID algorithm to perform operation to obtain a first target reference value; Based on the first target reference value, the crystal oscillator frequency of the local node is adjusted to obtain a corrected period of the clock signal of the local node.

5. The wireless multi-node time-frequency synchronization method according to any one of claims 1 to 4, characterized in that: The PID algorithm adopts an incremental PID algorithm; performing PID algorithm calculation based on the phase deviation and adjusting the phase of the clock signal of the local node according to the calculation result include: The phase deviation is used as an input of the incremental PID algorithm to perform calculation to obtain a second target reference value; Adjusting the phase of the clock signal of the local node based on the second target reference value; The second target reference amount is calculated by the following formula: Δu2=K P (e(k)-e(k-1))+K I *e(k)+K D (e(k)-2e(k-1)+ e(k-2)); Wherein, Δu2 represents the second target reference value; e(k) represents the phase deviation between the phase of the clock signal of the local node and the phase of the clock signal of the transmitting node at time k; K P Indicates the proportional magnification factor; K I Indicates the integral amplification factor; K D represents the differential amplification factor.

6. The wireless multi-node time-frequency synchronization method according to any one of claims 1 to 4, characterized in that: The local node is provided with a time-to-digital converter, which is used to measure the period and phase of the clock signal of the local node and the period and phase of the clock signal of the transmitting node.

7. A wireless multi-node time-frequency synchronization device, characterized in that: include: A receiving module, configured to receive the clock signal cluster broadcast by the transmitting node; a processing module, configured to determine a period deviation between a clock signal of a local node and a clock signal of the transmitting node based on a measurement result of the clock signal cluster; a measuring module, configured to measure a phase deviation between a clock signal of the local node and a received clock signal of the transmitting node when it is determined that the period deviation is less than a target threshold; a synchronization module, configured to perform PID algorithm calculation based on the phase deviation, and adjust the phase of the clock signal of the local node according to the calculation result to achieve time and frequency synchronization between the transmitting node and the local node; Before measuring the phase deviation between the clock signal of the local node and the received clock signal of the transmitting node when it is determined that the period deviation is less than the target threshold, the method further includes: Step S1, when it is determined that the period deviation is not less than a target threshold, performing a PID algorithm calculation based on the period deviation, adjusting the crystal oscillator frequency of the local node according to the calculation result, and determining a corrected period of the clock signal of the local node; Step S2, receiving the clock signal cluster broadcast by the transmitting node, and determining the period deviation between the correction period and the clock signal period of the transmitting node; When it is determined that the period deviation is not less than the target threshold, steps S1 to S2 are performed until it is determined that the period deviation is less than the target threshold, so as to achieve frequency synchronization between the clock signal of the local node and the clock signal of the transmitting node.

8. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the wireless multi-node time and frequency synchronization method as described in any one of claims 1 to 5 is implemented.

9. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the wireless multi-node time and frequency synchronization method according to any one of claims 1 to 5 is implemented.

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