Method, device, electronic device and storage medium for determining initial frequency deviation value

Abstract

The present application relates to the field of electronic communication technology, and specifically to a method, device, electronic device and storage medium for determining an initial frequency deviation value. The present application selects a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, calculates the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and compares it with a preset threshold to screen a suitable frequency deviation value, and finally selects the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition as the initial frequency deviation value. This method solves the problem of difficult and inaccurate calculation of the initial frequency deviation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

Description

Technical Field

[0001] The present application relates to the field of electronic communication technology, and in particular to a method, device, electronic device and storage medium for determining an initial frequency deviation value. Background Art

[0002] In the communication system of the power industry, the EPDT (Electric Power Data Transmission) protocol is an important communication protocol, and its stability and reliability are crucial to the normal operation of the power system. However, during the communication process of the EPDT protocol, due to the frequency difference between the crystal oscillators at the transmitting and receiving ends, as well as the Doppler frequency shift caused by the multipath effect and speed change, the frequencies at both ends of the transmitter and receiver often deviate, that is, frequency deviation. If this frequency deviation is too large, it will cause phase flipping, thereby affecting the accuracy of frame synchronization, and even causing missynchronization or missed synchronization, seriously affecting the stability and reliability of communication.

[0003] In order to achieve effective frame synchronization, you first need to find the training sequence in the protocol, that is, the frame synchronization signal. However, in a large frequency offset environment, the frequency offset will cause a large phase difference between the received signal and the expected synchronization signal, so direct frame synchronization is often difficult to achieve. Therefore, before performing frame synchronization, you need to make a rough estimate of the frequency offset, that is, perform initial frequency offset calculation.

[0004] The purpose of the initial frequency offset calculation is to quickly and accurately calculate the frequency deviation between the transmitter and receiver based on the characteristics of the received signal before entering the channel estimation module. In this way, the calculated frequency offset value can be used to compensate the received signal for frequency offset, thereby reducing the impact of frequency offset on frame synchronization. However, the initial frequency offset calculation in a large frequency offset environment faces many challenges. On the one hand, due to the large frequency offset, the received signal may produce severe phase distortion, making the calculation of the initial frequency offset difficult. On the other hand, different communication systems have different tolerances for frequency offsets, and some systems may only tolerate very small frequency offsets, which requires the initial frequency offset calculation to have higher accuracy and stability.

[0005] It can be seen that in the prior art, in a large frequency offset environment, there are problems such as difficulty and inaccuracy in calculating the initial frequency offset, which in turn leads to the problem of missynchronization or missed synchronization. Summary of the invention

[0006] The purpose of the present application is to provide a method, device, electronic device and storage medium for determining an initial frequency deviation value, so as to solve the problem of missynchronization or missed synchronization caused by difficulty and inaccurate calculation of the initial frequency deviation in a large frequency deviation environment in the prior art.

[0007] In order to achieve the above purpose, the technical solution adopted in this application is as follows:

[0008] According to one aspect of an embodiment of the present application, a method for determining an initial frequency deviation value is provided, comprising: obtaining a first frequency deviation value from a preset frequency deviation value sequence, wherein a plurality of frequency deviation values ​​stored in the frequency deviation value sequence are determined according to the bandwidth of a current transmission signal; determining whether a first peak-to-average ratio corresponding to the first frequency deviation value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained by performing frequency deviation compensation on a transmission frequency value of the transmission signal using the first frequency deviation value; when it is determined that the first peak-to-average ratio matches the preset threshold, determining a frequency deviation value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and other peak-to-average ratios as the initial frequency deviation value, wherein the other peak-to-average ratios are peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

[0009] According to the above technical means, by selecting a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, and calculating the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and comparing it with the preset threshold, a suitable frequency deviation value is screened, and finally the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition is selected as the initial frequency deviation value. This method solves the problem of difficult and inaccurate initial frequency deviation calculation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

[0010] Further, the frequency offset value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios is determined as the initial frequency offset value, including: if the first frequency offset value does not match the first frequency offset value in the frequency offset value sequence, then obtaining a second frequency offset value of the same type as the first frequency offset value from the frequency offset value sequence after the first frequency offset value; determining a second peak-to-average ratio corresponding to the second frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio; and determining the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and the second peak-to-average ratio as the initial frequency offset value.

[0011] According to the above technical means, when the first frequency offset value does not match the first value of the preset frequency offset value sequence, subsequent frequency offset values ​​of the same type are intelligently selected for peak-to-average ratio calculation, and the first peak-to-average ratio is compared with the second peak-to-average ratio (or other subsequent peak-to-average ratios) to determine the frequency offset value corresponding to the maximum peak-to-average ratio as the initial frequency offset value, thereby achieving a more refined selection and optimization of the initial frequency offset value, significantly improving the accuracy and efficiency of frequency offset estimation, and more effectively ensuring the stability and reliability of the communication system, especially in complex and changeable communication environments.

[0012] Further, the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and other peak-to-average ratios is determined as the initial frequency offset value, including: if the first frequency offset value matches the first frequency offset value in the frequency offset value sequence, then obtaining the second frequency offset value and the third frequency offset value after the first frequency offset value from the frequency offset value sequence; respectively determining the second peak-to-average ratio corresponding to the second frequency offset value and the third peak-to-average ratio corresponding to the third frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio and the third peak-to-average ratio; and determining the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio, the second peak-to-average ratio and the third peak-to-average ratio as the initial frequency offset value.

[0013] According to the above technical means, when the first frequency offset value matches the first frequency offset value in the frequency offset value sequence, not only the subsequent frequency offset value (the second frequency offset value and its corresponding second peak-to-average ratio) is considered, but also the previous frequency offset value (the third frequency offset value and its corresponding third peak-to-average ratio) is considered, and the frequency offset value with the largest peak-to-average ratio among the three is determined as the initial frequency offset value. This approach broadens the range of frequency offset search and improves the accuracy and robustness of frequency offset estimation. Especially when facing complex and changeable communication conditions, this method can more comprehensively evaluate the impact of different frequency offset values ​​on signal quality, thereby selecting the optimal initial frequency offset value, effectively ensuring the frame synchronization performance of the communication system, and further enhancing the stability and reliability of communication.

[0014] Further, determining whether a first peak-to-average ratio corresponding to the first frequency deviation value matches a preset threshold includes: determining the first peak-to-average ratio corresponding to the first frequency deviation value; comparing the first peak-to-average ratio with the preset threshold, if the first peak-to-average ratio is greater than or equal to the preset threshold, determining that the first peak-to-average ratio matches the preset threshold, otherwise determining that the first peak-to-average ratio does not match the preset threshold.

[0015] According to the above technical means, the first peak-to-average ratio corresponding to the first frequency deviation value is accurately calculated and compared with the preset threshold to determine whether the first peak-to-average ratio meets the quality requirements. If the first peak-to-average ratio reaches or exceeds the preset threshold, it indicates that the current frequency deviation compensation effect is good and the frequency deviation value can be directly adopted; if it does not meet the requirements, further search and optimization are required. This approach not only improves the efficiency and accuracy of frequency deviation estimation, but also ensures that the selected frequency deviation value can effectively improve the signal quality, thereby ensuring the stability of the communication system while optimizing the communication performance, laying a solid foundation for subsequent frame synchronization and data transmission.

[0016] Further, a first peak-to-average ratio corresponding to the first frequency deviation value is determined, including: according to the first frequency deviation value, performing frequency deviation compensation on the transmission frequency value of the transmission signal to obtain the current frequency value of the transmission signal; within a preset synchronization time, continuously sampling the transmission signal at a preset sampling rate to obtain multiple groups of sampled data; windowing each group of sampled data according to a preset frame structure to obtain a data frame and an index corresponding to each group of sampled data, wherein the data frame includes multiple data blocks for performing correlation operations, and the index is used to identify the starting position of the data of the data frame; according to the data and index of the multiple data blocks in the data frame, the peak-to-average ratio corresponding to each group of sampled data is determined, wherein the peak-to-average ratio is the ratio of the peak value to the mean value in the correlation value, and the peak value is the correlation value obtained by correlation operation using the data of the multiple data blocks in the data frame; the maximum peak-to-average ratio among all the peak-to-average ratios is determined as the first peak-to-average ratio corresponding to the first frequency deviation value.

[0017] According to the above technical means, the peak-to-average ratio corresponding to the frequency offset value is accurately determined through processes such as fine frequency offset compensation, continuous sampling, data frame windowing, correlation operation, and peak-to-average ratio calculation. This method not only improves the accuracy and reliability of frequency offset estimation, but also enhances the efficiency of signal processing by optimizing the sampling strategy and data frame structure. By comparing all peak-to-average ratios and selecting the maximum value, it is ensured that the selected frequency offset value can maximize the signal quality, thereby ensuring the stability of the communication system while optimizing the anti-interference ability of the communication and the data transmission efficiency, providing a solid foundation for subsequent frame synchronization and data processing.

[0018] Further, according to the data and index of multiple data blocks in the data frame, the peak-to-average ratio corresponding to each group of sampled data is determined, including: multiplying the data of multiple data blocks in the data frame by the corresponding bits of the data of multiple data blocks after local polarization, taking the absolute values ​​and then adding them, to obtain the peak value corresponding to each group of sampled data; wherein the data of each data block in the data frame is the first synchronization sequence data or the first training sequence data; the data of the multiple data blocks after local polarization refers to the data obtained by performing a polarization operation on the data of multiple data blocks in a preset local reference sequence; the data of each data block in the local reference sequence is the second synchronization sequence data or the second training sequence data; the target correlation value sequence corresponding to each group of sampled data is determined according to the index; from before and after the index in the target correlation value sequence, a preset number of correlation values ​​are taken to sum and average, and the average value corresponding to each group of sampled data is the average value; and the ratio of the peak value to the average value corresponding to each group of sampled data is determined as the peak-to-average ratio.

[0019] According to the above technical means, by multiplying the data of multiple data blocks in the data frame with the corresponding bits of the data blocks after local polarization and adding the absolute values, an accurate peak value is obtained; at the same time, the target correlation value sequence is determined according to the index, and the preset number of correlation values ​​before and after the index are summed and averaged to obtain an accurate mean. This method not only improves the accuracy and stability of the peak-to-average ratio calculation, but also effectively reduces the impact of noise and interference on signal quality. By dividing the peak value by the mean to obtain the peak-to-average ratio, the signal quality can be evaluated more intuitively, providing strong support for subsequent signal processing and frequency offset estimation, thereby optimizing the performance and stability of the communication system.

[0020] Furthermore, the method for determining the initial frequency deviation value also includes: when it is determined that the first peak-to-average ratio does not match the preset threshold, obtaining a fourth frequency deviation value from the remaining frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value; determining whether a fourth peak-to-average ratio corresponding to the fourth frequency deviation value matches the preset threshold; when it is determined that the fourth peak-to-average ratio matches the preset threshold, determining the frequency deviation value corresponding to the fourth peak-to-average ratio and the maximum peak-to-average ratio among the other peak-to-average ratios as the initial frequency deviation value.

[0021] According to the above technical means, when it is determined that the first peak-to-average ratio does not meet the preset threshold requirement, a new candidate frequency offset value (fourth frequency offset value) can be intelligently selected from the remaining frequency offset values ​​for peak-to-average ratio calculation and comparison, and when the fourth peak-to-average ratio meets the preset threshold, the frequency offset value corresponding to the maximum peak-to-average ratio is further compared and selected as the initial frequency offset value. This process not only improves the flexibility and adaptability of frequency offset estimation, but also effectively avoids the degradation of system performance caused by a single frequency offset value not meeting the requirements. Through continuous iteration and optimization, it ensures that the selected initial frequency offset value can maximize the signal quality, thereby enhancing the stability and reliability of the communication system.

[0022] According to another aspect of an embodiment of the present application, there is also provided an initial frequency deviation value determination device, including: a preset frequency deviation acquisition module, used to obtain a first frequency deviation value from a preset frequency deviation value sequence, wherein the multiple frequency deviation values ​​stored in the frequency deviation value sequence are determined according to the bandwidth of the current transmission signal; a peak-to-average ratio analysis module, used to determine whether a first peak-to-average ratio corresponding to the first frequency deviation value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained after frequency deviation compensation is performed on a transmission frequency value of the transmission signal using the first frequency deviation value; an initial frequency deviation determination module, used to, when it is determined that the first peak-to-average ratio matches the preset threshold, determine the frequency deviation value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and other peak-to-average ratios as the initial frequency deviation value, wherein the other peak-to-average ratios are peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

[0023] According to another aspect of the embodiments of the present application, there is also provided an electronic device, including a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory communicate with each other via the communication bus; wherein the memory is used to store a computer program; and the processor is used to execute the method for determining the initial frequency deviation value in any of the above embodiments by running the computer program stored in the memory.

[0024] According to another aspect of the embodiments of the present application, a computer-readable storage medium is provided, in which a computer program is stored, wherein the computer program is configured to execute the method for determining the initial frequency offset value in any of the above embodiments when running.

[0025] Beneficial effects of this application:

[0026] This application selects a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, calculates the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and compares it with the preset threshold to screen the appropriate frequency deviation value, and finally selects the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition as the initial frequency deviation value. This method solves the problem of difficult and inaccurate initial frequency deviation calculation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0028] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0029] Figure 1 is a schematic diagram of a hardware environment of an optional method for determining an initial frequency offset value provided in an embodiment of the present application;

[0030] Figure 2 It is a flowchart of an optional method for determining an initial frequency deviation value provided in an embodiment of the present application;

[0031] Figure 3 It is a schematic diagram of the TDMA frame timing of a 25kHz carrier provided in an embodiment of the present application;

[0032] Figure 4is a schematic diagram of the time slot structure of a 25kHz carrier provided in an embodiment of the present application;

[0033] Figure 5 It is a schematic diagram of a preset frame structure when windowing corresponding to a 25kHz carrier provided in an embodiment of the present application;

[0034] Figure 6 is a structural block diagram of an optional initial frequency deviation value determination device provided in an embodiment of the present application;

[0035] Figure 7 is a structural block diagram of an optional electronic device provided in an embodiment of the present application;

[0036] Figure 8 It is a flowchart of another optional method for determining an initial frequency deviation value provided in an embodiment of the present application.

[0037] Reference numerals:

[0038] 102-terminal, 104-server, 600-initial frequency deviation value determination device, 601-preset frequency deviation acquisition module, 602-peak-to-average ratio analysis module, 603-initial frequency deviation determination module, 1501-processor, 1502-communication interface, 1503-memory, 1504-communication bus. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0040] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0041] According to one aspect of an embodiment of the present application, a method for determining an initial frequency deviation value is provided. Optionally, in this embodiment, the above-mentioned method for determining an initial frequency deviation value can be applied to a hardware environment consisting of a terminal and a server. The server is connected to the terminal via a network, and can be used to provide services for the terminal or a client installed on the terminal. A database can be set on the server or independently of the server to provide data storage services for the server.

[0042] The above network may include but is not limited to at least one of the following: wired network, wireless network. The above wired network may include but is not limited to at least one of the following: wide area network, metropolitan area network, local area network, and the above wireless network may include but is not limited to at least one of the following: WIFI (Wireless Fidelity), Bluetooth. The terminal may not be limited to a PC, a mobile phone, a tablet computer, etc.

[0043] The method for determining the initial frequency offset value of the embodiment of the present application may be executed by a server, a terminal, or both. The method for determining the initial frequency offset value of the embodiment of the present application may be executed by a terminal or a client installed thereon.

[0044] Taking the method for determining the initial frequency offset value in this embodiment executed by the server as an example, please refer to Figure 1 , Figure 1 is a schematic diagram of a hardware environment of an optional method for determining an initial frequency offset value provided in an embodiment of the present application, such as Figure 1 As shown, the hardware environment of the method for determining the initial frequency offset value includes: a terminal 102, and a server 104 connected to the terminal 102 via a network. The server 104 is used to execute the method for determining the initial frequency offset value of the embodiment of the present application to determine the initial frequency offset value; the terminal 102 is used to display the determined initial frequency offset value.

[0045] The method for determining the initial frequency offset value in this embodiment can be applied to the frequency offset calculation scenario in a large frequency offset environment. In this embodiment of the application, a 230 Hz carrier in EPDT protocol communication is used as an example to illustrate the above method for determining the initial frequency offset value.

[0046] When using the EPDT protocol for communication, the frequency difference between the crystal oscillators at the transmitting and receiving ends and the Doppler frequency shift caused by multipath and speed at both ends will cause a deviation in the frequency of the transmitting and receiving ends, that is, frequency deviation. If the frequency deviation is too large, the phase will be reversed, resulting in missynchronization or missed synchronization. Before synchronization, the frequency deviation value estimated based on the channel estimation of the previous frame is used to compensate for the frequency deviation of the current frame signal, and then synchronization is performed. However, at the beginning, the channel estimation module has not yet been entered, and the frequency deviation value cannot be obtained, so the frequency deviation cannot be corrected, and the subsequent frame synchronization cannot be effectively synchronized. According to the crystal oscillator error of 1PPM, taking the 230Hz carrier in the EPDT protocol communication as an example, when the crystal oscillators at both ends of the transmitter and receiver offset in two opposite directions, it is equivalent to 2PPM. The maximum frequency deviation at this time is: , and the general receiving link is resistant to a frequency deviation of 100Hz (slightly different depending on the system). In order to solve the problem of being able to effectively receive the transmission signal under a large frequency deviation, the initial frequency deviation determination method in this application is given. The initial frequency deviation determination method in this embodiment is applied to the receiving or transmitting terminal of the signal. The initial frequency deviation calculation process will be executed when the terminal is turned on or needs to be registered to a new base station. Generally, the base station does not require a frequency deviation calculation step. If necessary, the method is consistent with the initial frequency deviation determination method in this embodiment.

[0047] This embodiment provides a method for determining an initial frequency offset value running on the above server, see Figure 2 , Figure 2 is a flow chart of an optional method for determining an initial frequency deviation value provided in an embodiment of the present application, such as Figure 2 As shown, the method for determining the initial frequency offset value in the embodiment of the present application specifically includes the following steps:

[0048] Step S201, obtaining a first frequency offset value from a preset frequency offset value sequence, wherein a plurality of frequency offset values ​​stored in the frequency offset value sequence are determined according to a bandwidth of a current transmission signal;

[0049] Step S202, determining whether a first peak-to-average ratio corresponding to a first frequency offset value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained by performing frequency offset compensation on a transmission frequency value of the transmission signal using the first frequency offset value;

[0050] Step S203, when it is determined that the first peak-to-average ratio matches the preset threshold, the frequency deviation value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios is determined as the initial frequency deviation value, wherein the other peak-to-average ratios are the peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

[0051] Through the above steps S201 to S203, a frequency deviation value is selected from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, and the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation is calculated, and compared with the preset threshold to screen the appropriate frequency deviation value, and finally the frequency deviation value with the maximum peak-to-average ratio and meeting the threshold condition is selected as the initial frequency deviation value. This method solves the problem of difficult and inaccurate initial frequency deviation calculation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

[0052] Combine the following Figure 2 The method for determining the initial frequency offset value in the embodiment of the present application is explained.

[0053] In the technical solution of step S201, a first frequency offset value is obtained from a preset frequency offset value sequence.

[0054] In this embodiment, the multiple frequency offset values ​​stored in the frequency offset value sequence are determined according to the bandwidth of the current transmission signal. In specific practice, nine-point frequency offset values ​​are used for synchronization, that is, nine preset frequency offset values ​​are stored in the frequency offset value sequence, and the nine-point frequency offset values ​​can be configured according to the specific situation of the bandwidth of the current transmission signal. For example, the preset frequency offset value Including: 0Hz, ±50Hz, ±150Hz, ±250Hz, ±350Hz, which are stored in the following order: 0Hz, +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz. When determining the initial frequency deviation value, the first frequency deviation value is obtained in sequence according to the stored order for synchronization, and the peak-to-average ratio corresponding to the first frequency deviation value is determined.

[0055] If the peak-to-average ratio exceeds the threshold at a certain frequency offset value in the frequency offset value sequence, the peak-to-average ratio of the frequency offset value to the right or left is calculated, and the offset value corresponding to the maximum peak-to-average ratio is found, and the offset value at this time is determined as the initial frequency offset value. . When determining the initial frequency deviation value Then it goes to the next level of channel estimation. When changing channels for reception (for example, when the control channel is changed to the service channel), the configured receiving frequency must be added with the initial frequency deviation value, that is: .in, Represents the current receiving frequency, represents the initial frequency deviation value, Represents the compensated receiving frequency. When the terminal transmits, the configured transmit frequency also needs to add the initial frequency deviation value, that is: .in, Represents the current transmission frequency, represents the initial frequency deviation value, Represents the compensated transmit frequency.

[0056] In the technical solution of step S202, it is determined whether a first peak-to-average ratio corresponding to the first frequency offset value matches a preset threshold.

[0057] In this embodiment, the first peak-to-average ratio is the ratio between the peak and the mean of the correlation value corresponding to the current frequency value of the transmission signal, and the current frequency value is the frequency value obtained by using the first frequency deviation value to compensate for the transmission frequency value of the transmission signal.

[0058] As an optional embodiment, determining whether a first peak-to-average ratio corresponding to a first frequency deviation value matches a preset threshold includes: determining the first peak-to-average ratio corresponding to the first frequency deviation value; comparing the first peak-to-average ratio with the preset threshold, if the first peak-to-average ratio is greater than or equal to the preset threshold, determining that the first peak-to-average ratio matches the preset threshold, otherwise determining that the first peak-to-average ratio does not match the preset threshold.

[0059] It can be understood that the first peak-to-average ratio corresponding to the first frequency deviation value is accurately calculated and compared with the preset threshold to determine whether the first peak-to-average ratio meets the quality requirements. If the first peak-to-average ratio reaches or exceeds the preset threshold, it indicates that the current frequency deviation compensation effect is good and the frequency deviation value can be directly adopted; if it does not meet the requirements, further search and optimization are required. This approach not only improves the efficiency and accuracy of frequency deviation estimation, but also ensures that the selected frequency deviation value can effectively improve the signal quality, thereby ensuring the stability of the communication system while optimizing the communication performance, laying a solid foundation for subsequent frame synchronization and data transmission.

[0060] In specific practice, when determining whether the first peak-to-average ratio corresponding to the first frequency offset value matches the preset threshold, the most important thing is how to determine the peak-to-average ratio corresponding to the frequency offset value.

[0061] As an optional embodiment, determining a first peak-to-average ratio corresponding to a first frequency deviation value includes: according to the first frequency deviation value, performing frequency deviation compensation on the transmission frequency value of the transmission signal to obtain the current frequency value of the transmission signal; within a preset synchronization time, continuously sampling the transmission signal at a preset sampling rate to obtain multiple groups of sampled data; windowing each group of sampled data according to a preset frame structure to obtain a data frame and an index corresponding to each group of sampled data, wherein the data frame includes multiple data blocks for performing correlation operations, and the index is used to identify the starting position of the data of the data frame; determining the peak-to-average ratio corresponding to each group of sampled data based on the data and index of the multiple data blocks in the data frame, wherein the peak-to-average ratio is the ratio of the peak value to the mean value in the correlation value, and the peak value is the correlation value obtained by correlation operation using the data of the multiple data blocks in the data frame; determining the maximum peak-to-average ratio among all the peak-to-average ratios as the first peak-to-average ratio corresponding to the first frequency deviation value.

[0062] In specific practice, the current frequency value can be determined by the following formula: ,in, represents the preset frequency deviation value obtained, that is, the first frequency deviation value, Represents the received frequency value of the transmission signal, Represents the current frequency value. Synchronize the signal within the preset synchronization time at the current frequency value. If synchronization cannot be achieved, enter the frequency value corresponding to the next frequency deviation value to continue synchronization. The synchronization time at each current frequency value can be set according to the specific situation. For example, the synchronization time for each current frequency value is 90ms. The sampling rate SampleRate can be set according to the actual situation. For example, if the sampling rate SampleRate is 4Hz, the original data is sampled 4 times per second.

[0063] In specific practice, since the number of each set of sampled data obtained by sampling corresponding to different carriers is also different, the number of each set of sampled data can also be set according to actual conditions, for example, the number of each set of sampled data can be set to the number of valid data in a time slot of each frame. It can be understood that by sampling the original data, multiple sets of sampled data are obtained, and each set of sampled data has a preset number of data.

[0064] The following uses a 25kHz carrier as an example to illustrate the above sampling steps. Figure 3 , Figure 3 Schematic diagram of the TDMA frame timing of a 25kHz carrier provided in an embodiment of the present application, such as Figure 3 As shown, the length of each TDMA frame in the carrier is 60ms, and the TDMA frame consists of two 30ms time slots. The effective data center of each time slot is the center position of the effective symbol in the burst. For the structure of each time slot, please refer to Figure 4 , Figure 4 Schematic diagram of the time slot structure of the 25kHz carrier provided in the embodiment of the present application. Figure 4As shown, each time slot contains 6 payload areas of 99 symbols, 3 synchronization sequence data SYNC areas of 16 symbols, 4 training sequence data TSC areas of 16 symbols, 2 tail bit Tb areas of 3 symbols and 2 protection GP areas. The 3 synchronization areas constitute 1 synchronization word, and the 4 training sequences are divided into 2 groups, each containing 32 symbols, which are located on both sides of the payload at both ends of the time slot. The total duration of each time slot is 30ms, of which there are 712 valid symbols, and the duration corresponding to the valid symbols is 28.48ms. If the sampling rate SampleRate is 4, then after sampling the 25kHz carrier through the above steps, 4 groups of sampled data are obtained, and each group of sampled data includes 712 data. It can be understood that sampling the original data through the sampling rate can accurately represent the original signal, improve the signal quality, avoid aliasing, facilitate subsequent processing, and have flexibility and scalability.

[0065] In the scheme of this embodiment, after acquiring the sampled data, not all the sampled data are used for correlation calculation, but part of the data is taken for correlation calculation. Specifically, the data for correlation calculation is acquired by windowing according to the preset frame structure. The preset frame structure is the same as the structure corresponding to the valid data in the structure of each time slot in the carrier. The data frame is composed of multiple data blocks, each data block includes multiple data, and the data in each data block is the first synchronization sequence data SYNC or the first training sequence data TSC. The index is used to identify the data starting position of the data frame.

[0066] Taking the above 25kHz carrier as an example, the preset frame structure used when opening the window can be found in Figure 5 , Figure 5 25kHz carrier provided in the embodiment of the present application corresponding to the preset frame structure when the window is opened, such as Figure 5 As shown, the preset frame structure includes 712 valid data when the window is opened, and the first synchronization sequence data SYNC and the first training sequence data TSC are involved in the relevant calculation in this application. It can be seen from the preset frame structure that the first synchronization sequence data SYNC and the first training sequence data TSC are composed of multiple, discontinuous data blocks, and each data block includes a certain amount of data. Therefore, after opening the window according to the preset frame structure, a total of 3 first synchronization sequence data SYNC and 4 first training sequence data TSC are obtained, each sequence data is a data block, and the number of data in each sequence is the number of data in each data block. The index is used to identify the starting position of the data of the data frame. It can be understood that by opening the window according to the preset frame structure to obtain data of multiple synchronization sequences and training sequences, it is helpful to perform frame synchronization more accurately in the future, and at the same time, it can better deal with frequency deviation and noise interference.

[0067] In specific practice, when determining the peak-to-average ratio corresponding to each group of sampled data according to the data and indexes of multiple data blocks in the data frame, the peak value MaxValue and the average value Average in the correlation value are first determined by performing correlation operations on multiple data blocks in the data frame, and then the ratio of the peak value MaxValue to the average value Average is determined as the frame synchronization peak-to-average ratio PAPR. The calculation process of the above peak-to-average ratio PAPR can be summarized as the following formula: PAPR=MaxValue / Average. In this embodiment, the peak value MaxValue is a correlation value obtained by correlation operations using the data of multiple data blocks in the data frame.

[0068] It can be understood that the peak-to-average ratio corresponding to the frequency offset value is accurately determined through the processes of fine frequency offset compensation, continuous sampling, data frame windowing, correlation operation, and peak-to-average ratio calculation. This method not only improves the accuracy and reliability of frequency offset estimation, but also enhances the efficiency of signal processing by optimizing the sampling strategy and data frame structure. By comparing all peak-to-average ratios and selecting the maximum value, it is ensured that the selected frequency offset value can maximize the signal quality, thereby ensuring the stability of the communication system while optimizing the anti-interference ability of the communication and the data transmission efficiency, providing a solid foundation for subsequent frame synchronization and data processing.

[0069] As an optional embodiment, according to the data and index of multiple data blocks in the data frame, the peak-to-average ratio corresponding to each group of sampled data is determined, including: multiplying the data of multiple data blocks in the data frame by the corresponding bits of the data of multiple data blocks after local polarization, taking the absolute values ​​and then adding them, to obtain the peak value corresponding to each group of sampled data; wherein the data of each data block in the data frame is the first synchronization sequence data or the first training sequence data; the data of the multiple data blocks after local polarization refers to the data obtained by performing a polarization operation on the data of multiple data blocks in a preset local reference sequence; the data of each data block in the local reference sequence is the second synchronization sequence data or the second training sequence data; determining the target correlation value sequence corresponding to each group of sampled data according to the index; taking a preset number of correlation values ​​from before and after the index in the target correlation value sequence, summing and averaging them, and the mean value corresponding to each group of sampled data is the mean value; and determining the ratio of the peak value to the mean value corresponding to each group of sampled data as the peak-to-average ratio.

[0070] In specific practice, the local reference sequence includes data of multiple data blocks, wherein the data of each data block is the second synchronization sequence data SYNC´ or the second training sequence data TSC´. When obtaining the peak value corresponding to each group of sampled data, the second synchronization sequence data SYNC´ and the second training sequence data TSC´ in the local reference sequence are firstly subjected to local polarization operation to obtain the third synchronization sequence data SYNC_LOCAL and the third training sequence data TSC_LOCAL; then the first synchronization sequence data SYNC and the first training sequence data TSC in the data frame are multiplied by the data at the corresponding positions of the third synchronization sequence SYNC_LOCAL and the third training sequence TSC_LOCAL after local polarization, and the absolute values ​​are taken and then added to obtain the correlation value. The correlation value is saved in the target correlation value sequence SumValue. The "corresponding position" here refers to the position occupied by each data in the first synchronization sequence data SYNC and the first training sequence data TSC in the preset frame structure. It can be understood that the similarity between the two sequences is calculated by correlation operation, and then the time domain shift of the two sequences is determined. When the correlation value of the two sequences reaches a peak value, it means that they are synchronized in time.

[0071] As an optional embodiment, performing a local polarization operation on the second synchronization sequence data and the second training sequence data in the local reference sequence to obtain third synchronization sequence data and third training sequence data includes: using a 1-2*local conversion rule to convert each bit of the second synchronization sequence data and the second training sequence data to obtain corresponding third synchronization sequence data and third training sequence data, wherein local represents each bit of data to be converted in the local reference sequence.

[0072] In this embodiment, the local polarization operation is actually to change the data in the second synchronization sequence data SYNC´ and the second training sequence data TSC´ in the local reference sequence from 0 to 1 or from 1 to -1, and obtain the corresponding third synchronization sequence data SYNC_LOCAL and third training sequence data TSC_LOCAL after conversion. As an optional specific implementation, in this embodiment, the conversion rule of "1-2*local" is used to convert the data at the corresponding positions of the second synchronization sequence data SYNC´ and the second training sequence data TSC´ in the local reference sequence, where local is a Boolean value (that is, 0 or 1), then this expression can be interpreted as: when local is 0, 1-2*0=1, which is equivalent to changing "0 to 1"; when local is 1, 1-2*1=-1, which is equivalent to changing "1 to -1".

[0073] It can be understood that through this specific conversion rule, the polarization direction of the local reference sequence can be clearly controlled, so as to better match or distinguish different signals, help to better identify and synchronize the start and end positions of the frame, reduce the possibility of missynchronization, and improve the accuracy and reliability of communication. Moreover, the conversion rule is implemented using simple mathematical operations, which helps to simplify the calculation process and improve processing efficiency.

[0074] As an optional embodiment, the target correlation value sequence corresponding to each group of sampled data is determined according to the index, including: starting from the data starting position identified by the index, sliding the window backward according to a preset frame length and a preset frame shift, and obtaining a target data frame each time a window is slid; determining the target correlation value corresponding to the target data frame, wherein each target correlation value corresponds to a target index, and the target index identifies the data starting position corresponding to the target data frame; and sorting the target correlation values ​​in the order of appearance of the data starting position identified by the target index to obtain a target correlation value sequence.

[0075] In specific practice, data is divided into multiple target data frames according to a preset frame length and a preset frame shift, wherein each target data frame corresponds to a target index, and the target index identifies the data starting position corresponding to the target data frame; the correlation value corresponding to each target data frame is determined; all correlation values ​​are stored in the order in which the data starting position identified by the target index appears, and a target correlation value sequence is obtained. The preset frame length is the length of valid data in a time slot corresponding to each carrier, and the data of the preset frame length is called a data frame. The preset frame shift is the step length of each movement when dividing the data frame. The frame shift can be set according to the specific situation. In this embodiment, the frame shift is 1, that is, 1 data is moved each time.

[0076] Taking the above 25kHz carrier as an example, starting from the starting position of the sampled data, the original data is divided backward according to 712 (preset frame length) and 1 (preset frame moving step) to obtain multiple target data frames. Among them, each target data frame corresponds to a target index, and the starting position of each target data frame is the data starting position indicated by the target index. Through the correlation operation, the target correlation value corresponding to each target data frame, all target correlation values ​​are sorted and stored in the order of appearance of the starting position of the target data frame, and the target correlation value sequence SumValue is obtained.

[0077] It can be understood that, within the sliding window, the correlation of the data within the window can be calculated. Since the data within the window has a certain continuity, this window-based synchronization method can improve the accuracy of the mean; and the use of the method in the present application can avoid aimless searching of the entire data stream, which helps to optimize the utilization of system resources and reduce unnecessary computing and storage overhead; the method in this embodiment can also adjust the window size and sliding step size according to factors such as frame length, data rate, channel conditions, etc. to adapt to different communication environments and requirements, with high flexibility.

[0078] As an optional embodiment, a preset number of correlation values ​​are taken from the target correlation value sequence before and after indexing, and the sum is taken as an average, including: after indexing from the target correlation value sequence, a first number of correlation values ​​are taken and summed to obtain a first value; before indexing from the target correlation value sequence, a second number of correlation values ​​are taken and summed to obtain a second value; the first value and the second value are summed to obtain a third value; the first number and the second number are summed to obtain a fourth value; and the ratio of the third value to the fourth value is determined as the average.

[0079] In this embodiment, the first number num1 and the second number num2 are set according to actual conditions, and the first number num1 may be the same as the second number num2, or may be different. After the index in the target correlation value sequence specifically refers to: after num_offset indexes after the index corresponding to the peak value in the target correlation value sequence; before the index in the target correlation value sequence specifically refers to: before num_offset indexes before the index corresponding to the peak value in the target correlation value sequence. For example: the target correlation value sequence SumValue stores multiple correlation values, and each correlation value corresponds to an index Index, then after the index in the target correlation value sequence specifically refers to after Index+num_offset; before the index in the target correlation value sequence specifically refers to before Index-num_offset. As an optional specific implementation method, the value of num_offset can be set according to actual conditions, and is not specifically limited here. For example: num_offset is 2. It can be understood that num_offset is used to indicate the number of correlation values ​​skipped before or after the index corresponding to the peak in the target correlation value sequence. By skipping num_offset correlation values ​​before and after the index corresponding to the peak in the target correlation value sequence, the influence of noise and outliers can be effectively reduced, the accuracy and robustness of data processing can be improved, and the utilization of computing resources can be optimized, thereby enhancing the adjustability of the algorithm and the interpretability of the results.

[0080] Therefore, the first value Sum1 is the sum of num1 related values ​​after Index + num_offset in SumValue, and the second value Sum2 is the sum of num2 related values ​​before Index - num_offset in SumValue. The third value Sum3 is the sum of Sum1 and Sum2; the fourth value Sum4 is the sum of num1 and num2, and the final average Average = Sum3 / Sum4.

[0081] It can be understood that by calculating the mean of a certain number of frame synchronization values ​​on the left and right sides of the frame synchronization peak, since Sum1 and Sum2 can represent the trend or strength in two different time windows before and after the Index position, by considering multiple points (rather than a single point) to calculate the sum, the impact caused by a single outlier or noise point can be reduced, making the result more stable and reliable. Since the mean reflects the average state of the signal over a period of time, it has a smoothing effect on the fluctuations and random changes of the signal. Therefore, introducing the mean as part of the peak-to-average ratio can improve the stability and reliability of frame synchronization.

[0082] It can be understood that by multiplying the data of multiple data blocks in the data frame with the corresponding bits of the data blocks after local polarization and adding the absolute values, an accurate peak value is obtained; at the same time, the target correlation value sequence is determined according to the index, and the preset number of correlation values ​​before and after the index are summed and averaged to obtain an accurate mean. This method not only improves the accuracy and stability of the peak-to-average ratio calculation, but also effectively reduces the impact of noise and interference on signal quality. By dividing the peak value by the mean to obtain the peak-to-average ratio, the signal quality can be evaluated more intuitively, which provides strong support for subsequent signal processing and frequency offset estimation, thereby optimizing the performance and stability of the communication system.

[0083] In the technical solution of step S203, when it is determined that the first peak-to-average ratio matches the preset threshold, the frequency offset value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among the other peak-to-average ratios is determined as the initial frequency offset value. In this embodiment, the other peak-to-average ratios are the peak-to-average ratios corresponding to the other frequency offset values ​​in the frequency offset value sequence except the first frequency offset value.

[0084] As an optional embodiment, the frequency offset value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios is determined as the initial frequency offset value, including: if the first frequency offset value does not match the first frequency offset value in the frequency offset value sequence, then obtaining a second frequency offset value of the same type as the first frequency offset value from the frequency offset value sequence after the first frequency offset value; determining a second peak-to-average ratio corresponding to the second frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio; and determining the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and the second peak-to-average ratio as the initial frequency offset value.

[0085] In specific practice, the first frequency deviation value in the frequency deviation value sequence refers to the first preset frequency deviation value stored in order. Since the frequency deviation values ​​stored in the frequency deviation value sequences corresponding to different carriers are different, the first frequency deviation value in the frequency deviation value sequence is not fixed. For example, the following frequency deviation values ​​are stored in the frequency deviation value sequence in order: 0Hz, +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz, then the first frequency deviation value in the frequency deviation value sequence refers to 0Hz.

[0086] Take the frequency deviation value sequence above as an example, where the following frequency deviation values ​​are stored in order: 0Hz, +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz. If the first frequency deviation value is not 0Hz, it means that the first frequency deviation value does not match the first frequency deviation value in the frequency deviation value sequence. Assuming that the first frequency deviation value is +150Hz at this time, and its corresponding peak-to-average ratio exceeds the threshold, then it is necessary to detect the peak-to-average ratio of the second frequency deviation value after the first frequency deviation value. At this time, the second frequency deviation value is +250Hz, and the frequency deviation value corresponding to the maximum peak-to-average ratio of the two is determined as the initial frequency deviation value. Assuming that the first frequency deviation value is -50Hz at this time, and its corresponding peak-to-average ratio exceeds the threshold, then it is necessary to detect the peak-to-average ratio of the second frequency deviation value after the first frequency deviation value. At this time, the second frequency deviation value is -150Hz, and the frequency deviation value corresponding to the maximum peak-to-average ratio of the two is determined as the initial frequency deviation value.

[0087] It can be understood that when the first frequency offset value does not match the first value of the preset frequency offset value sequence, subsequent frequency offset values ​​of the same type are intelligently selected for peak-to-average ratio calculation, and the first peak-to-average ratio is compared with the second peak-to-average ratio (or other subsequent peak-to-average ratios) to determine the frequency offset value corresponding to the maximum peak-to-average ratio as the initial frequency offset value, thereby achieving a more refined selection and optimization of the initial frequency offset value, significantly improving the accuracy and efficiency of frequency offset estimation, and more effectively ensuring the stability and reliability of the communication system, especially in complex and changeable communication environments.

[0088] As an optional embodiment, the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio and other peak-to-average ratios is determined as the initial frequency offset value, including: if the first frequency offset value matches the first frequency offset value in the frequency offset value sequence, then obtaining the second frequency offset value and the third frequency offset value after the first frequency offset value from the frequency offset value sequence; respectively determining the second peak-to-average ratio corresponding to the second frequency offset value and the third peak-to-average ratio corresponding to the third frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio and the third peak-to-average ratio; and determining the frequency offset value corresponding to the maximum peak-to-average ratio among the first peak-to-average ratio, the second peak-to-average ratio and the third peak-to-average ratio as the initial frequency offset value.

[0089] Taking the following frequency deviation values ​​stored in the above frequency deviation value sequence in order: 0Hz, +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz as an example, if the first frequency deviation value is 0Hz, it means that the first frequency deviation value matches the first frequency deviation value in the frequency deviation value sequence. At this time, the first frequency deviation value is 0Hz, and its corresponding peak-to-average ratio exceeds the threshold. Then it is necessary to detect the peak-to-average ratios of the two points of ±50 again. The second frequency deviation value after the first frequency deviation value is +50Hz, and the third frequency deviation value after the first frequency deviation value is -50Hz. The frequency deviation value corresponding to the maximum peak-to-average ratio among the three is determined as the initial frequency deviation value.

[0090] It can be understood that by considering not only the subsequent frequency offset values ​​(the second frequency offset value and its corresponding second peak-to-average ratio) but also the previous frequency offset values ​​(the third frequency offset value and its corresponding third peak-to-average ratio) when the first frequency offset value matches the first frequency offset value in the frequency offset value sequence, and determining the frequency offset value with the largest peak-to-average ratio among the three as the initial frequency offset value, this approach broadens the range of frequency offset search and improves the accuracy and robustness of frequency offset estimation. Especially when facing complex and changing communication conditions, this method can more comprehensively evaluate the impact of different frequency offset values ​​on signal quality, thereby selecting the optimal initial frequency offset value, effectively ensuring the frame synchronization performance of the communication system, and further enhancing the stability and reliability of communication.

[0091] As an optional embodiment, the method for determining the initial frequency deviation value also includes: when it is determined that the first peak-to-average ratio does not match a preset threshold, obtaining a fourth frequency deviation value from the remaining frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value; determining whether a fourth peak-to-average ratio corresponding to the fourth frequency deviation value matches the preset threshold; when it is determined that the fourth peak-to-average ratio matches the preset threshold, determining the frequency deviation value corresponding to the fourth peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios as the initial frequency deviation value.

[0092] In specific practice, the fourth frequency offset value is a frequency offset value remaining in the frequency offset value sequence except the first frequency offset value. Taking the frequency offset value sequence as an example, the following frequency offset values ​​are stored in order: 0Hz, +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz. If the first frequency offset value is 0Hz, then the fourth frequency offset value is any one of +50Hz, -50Hz, +150Hz, -150Hz, +250Hz, -250Hz, +350Hz, -350Hz.

[0093] It is understandable that when it is determined that the first peak-to-average ratio does not meet the preset threshold requirement, a new candidate frequency offset value (fourth frequency offset value) can be intelligently selected from the remaining frequency offset values ​​for peak-to-average ratio calculation and comparison, and when the fourth peak-to-average ratio meets the preset threshold, the frequency offset value corresponding to the maximum peak-to-average ratio is further compared and selected as the initial frequency offset value. This process not only improves the flexibility and adaptability of frequency offset estimation, but also effectively avoids the degradation of system performance caused by a single frequency offset value not meeting the requirements. Through continuous iteration and optimization, it ensures that the selected initial frequency offset value can maximize the signal quality, thereby enhancing the stability and reliability of the communication system.

[0094] In specific practice, the initial frequency offset determination method in this embodiment adopts Figure 8 The calculation process shown is as follows: Figure 8 As shown, the calculation process includes the following steps:

[0095] Step S81: according to the setting order of the frequency offset values ​​in the frequency offset sequence, obtain the frequency offset value after the frequency offset is preset, and execute step S82;

[0096] Step S82: configuring the receiving frequency of the transmission signal according to the frequency deviation value, obtaining the configured current frequency value, and executing step S83;

[0097] Step S83: Use the configured current frequency value to perform frame synchronization, determine the peak-to-average ratio, and execute step S84;

[0098] Step S84: determining whether the peak-to-average ratio exceeds a threshold value, if so, executing step S85, if not, executing step S81, reselecting a frequency offset value from the remaining frequency offset values ​​in the frequency offset sequence;

[0099] Step S85: set the next frequency value, detect the frame synchronization value again, find the frequency deviation value corresponding to the maximum peak-to-average ratio, and execute step S86;

[0100] Step S86: Channel estimation, end.

[0101] It can be understood that the technical solution provided by this embodiment selects a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, calculates the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and compares it with the preset threshold to screen the appropriate frequency deviation value, and finally selects the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition as the initial frequency deviation value. This method solves the problem of difficult and inaccurate initial frequency deviation calculation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

[0102] It should be noted that, for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0103] Through the description of the above implementation methods, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a software product, which is stored in a storage medium (such as ROM (Read-Only Memory, read-only memory) / RAM (Random Access Memory, random access memory), a magnetic disk, or an optical disk), and includes a number of instructions for a terminal device (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods of each embodiment of the present application.

[0104] According to another aspect of the embodiments of the present application, there is also provided an initial frequency offset value determining device for implementing the above-mentioned initial frequency offset value determining method. Figure 6 , Figure 6 is a structural block diagram of an optional initial frequency deviation value determination device provided in an embodiment of the present application, such as Figure 6 As shown, the initial frequency offset value determining device 600 may include:

[0105] A preset frequency offset acquisition module 601, configured to acquire a first frequency offset value from a preset frequency offset value sequence, wherein the plurality of frequency offset values ​​stored in the frequency offset value sequence are determined according to the bandwidth of the current transmission signal;

[0106] A peak-to-average ratio analysis module 602 is used to determine whether a first peak-to-average ratio corresponding to a first frequency offset value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained by performing frequency offset compensation on a transmission frequency value of the transmission signal using the first frequency offset value;

[0107] The initial frequency deviation determination module 603 is used to determine the frequency deviation value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios as the initial frequency deviation value when it is determined that the first peak-to-average ratio matches a preset threshold, wherein the other peak-to-average ratios are the peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

[0108] It should be noted that the preset frequency offset acquisition module 601 in this embodiment can be used to execute the above step S201, the peak-to-average ratio analysis module 602 in this embodiment can be used to execute the above step S202, and the initial frequency offset determination module 603 in this embodiment can be used to execute the above step S203.

[0109] Regarding the initial frequency offset value determination device 600 in this embodiment, the specific manner in which its preset frequency offset acquisition module 601, peak-to-average ratio analysis module 602 and initial frequency offset determination module 603 execute the above-mentioned initial frequency offset value determination method has been described in detail in the embodiment of the initial frequency offset value determination method, and will not be elaborated here.

[0110] It can be understood that the technical solution provided by this embodiment, each module in the initial frequency deviation value determination device, selects a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, and calculates the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and compares it with the preset threshold to screen the appropriate frequency deviation value, and finally selects the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition as the initial frequency deviation value. This method solves the problem of difficult and inaccurate initial frequency deviation calculation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

[0111] The device in this embodiment, in addition to the above modules, may also include a module for executing any method in any of the above embodiments of the method for determining an initial frequency offset value.

[0112] It should be noted that the above modules and corresponding steps implement the same examples and application scenarios, but are not limited to the contents disclosed in the above embodiments. It should be noted that the above modules, as part of the device, can be run in the implementation of Figure 1 The hardware environment of the method shown may be implemented by software or hardware, wherein the hardware environment includes a network environment.

[0113] According to another aspect of an embodiment of the present application, an electronic device for implementing the above-mentioned method for determining an initial frequency offset value is also provided. The electronic device may be a server, a terminal, or a combination thereof.

[0114] According to another embodiment of the present application, an electronic device is also provided. Figure 7 , Figure 7 is a structural block diagram of an optional electronic device provided in an embodiment of the present application, such as Figure 7As shown, the electronic device may include: a processor 1501 , a communication interface 1502 , a memory 1503 and a communication bus 1504 , wherein the processor 1501 , the communication interface 1502 , and the memory 1503 communicate with each other via the communication bus 1504 .

[0115] Memory 1503, used for storing computer programs;

[0116] The processor 1501 is used to implement the following steps when executing the program stored in the memory 1503:

[0117] Step S201, obtaining a first frequency offset value from a preset frequency offset value sequence, wherein a plurality of frequency offset values ​​stored in the frequency offset value sequence are determined according to a bandwidth of a current transmission signal;

[0118] Step S202, determining whether a first peak-to-average ratio corresponding to a first frequency offset value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained by performing frequency offset compensation on a transmission frequency value of the transmission signal using the first frequency offset value;

[0119] Step S203, when it is determined that the first peak-to-average ratio matches the preset threshold, the frequency deviation value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios is determined as the initial frequency deviation value, wherein the other peak-to-average ratios are the peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

[0120] It can be understood that the technical solution provided by this embodiment is that the processor of the electronic device selects a frequency deviation value from a preset frequency deviation value sequence determined according to the current transmission signal bandwidth, and calculates the peak-to-average ratio of the transmission signal after applying the frequency deviation value compensation, and compares it with the preset threshold to screen the appropriate frequency deviation value, and finally selects the frequency deviation value with the largest peak-to-average ratio and meeting the threshold condition as the initial frequency deviation value. This method solves the problem of difficult and inaccurate calculation of the initial frequency deviation in a large frequency deviation environment, effectively improves the accuracy and stability of frequency deviation estimation, thereby reducing the impact of frequency deviation on frame synchronization, and improving the stability and reliability of EPDT protocol communication in the power industry.

[0121] Optionally, in this embodiment, the above-mentioned communication bus can be a PCI (Peripheral Component Interconnect) bus, or an EISA (Extended Industry Standard Architecture) bus, etc. The communication bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one thick line is used in the figure, but it does not mean that there is only one bus or one type of bus. The communication interface is used for communication between the above-mentioned electronic device and other devices.

[0122] The memory may include a random access memory (RAM) or a non-volatile memory (NVM), such as at least one disk memory. Optionally, the memory may also be at least one storage device located away from the aforementioned processor.

[0123] The above-mentioned processor can be a general-purpose processor, which can include but not be limited to: CPU (Central Processing Unit), NP (Network Processor), etc.; it can also be DSP (Digital Signal Processor), ASIC (Application Specific Integrated Circuit), FPGA (Field-Programmable Gate Array) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components.

[0124] An embodiment of the present application further provides a computer-readable storage medium, the storage medium including a stored program, wherein the method steps of the above method embodiment are executed when the program is run.

[0125] Optionally, in this embodiment, the storage medium may include, but is not limited to, various media that can store program codes, such as a USB flash drive, a ROM, a RAM, a mobile hard disk, a magnetic disk, or an optical disk.

[0126] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0127] If the integrated units in the above embodiments are implemented in the form of software functional units and sold or used as independent products, they can be stored in the above computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for enabling one or more computer devices (which can be personal computers, servers or network devices, etc.) to execute all or part of the steps of the methods of each embodiment of the present application.

[0128] In the above embodiments of the present application, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, please refer to the relevant description of other embodiments.

[0129] In the several embodiments provided in the present application, it should be understood that the disclosed client can be implemented in other ways. Among them, the device embodiments described above are only schematic, for example, the division of units is only a logical function division, and there may be other division methods in actual implementation, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0130] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution provided in this embodiment.

[0131] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0132] The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.

Claims

1. A method for determining an initial frequency deviation value, characterized in that: include: Acquire a first frequency offset value from a preset frequency offset value sequence, wherein the plurality of frequency offset values ​​stored in the frequency offset value sequence are determined according to a bandwidth of a current transmission signal; Determine whether a first peak-to-average ratio corresponding to the first frequency deviation value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, and the current frequency value is a frequency value obtained by performing frequency deviation compensation on a transmission frequency value of the transmission signal using the first frequency deviation value, and determine the first peak-to-average ratio corresponding to the first frequency deviation value, including: performing frequency deviation compensation on a transmission frequency value of the transmission signal according to the first frequency deviation value to obtain the current frequency value of the transmission signal; and continuously sampling the transmission signal at a preset sampling rate within a preset synchronization time. Sampling to obtain multiple groups of sampled data; windowing each group of sampled data according to a preset frame structure to obtain a data frame and an index corresponding to each group of sampled data, wherein the data frame includes multiple data blocks for performing correlation operations, and the index is used to identify the data starting position of the data frame; determining the peak-to-average ratio corresponding to each group of sampled data according to the data and index of the multiple data blocks in the data frame, wherein the peak-to-average ratio is a ratio of a peak value to an average value in a correlation value, and the peak value is a correlation value obtained by a correlation operation using data of multiple data blocks in the data frame; determining the maximum peak-to-average ratio among all the peak-to-average ratios as the first peak-to-average ratio corresponding to the first frequency deviation value; When it is determined that the first peak-to-average ratio matches the preset threshold, the frequency deviation value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios is determined as the initial frequency deviation value, wherein the other peak-to-average ratios are the peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

2. The method for determining the initial frequency deviation value according to claim 1, characterized in that: Determining a frequency offset value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios as an initial frequency offset value comprises: If the first frequency offset value does not match the first frequency offset value in the frequency offset value sequence, obtaining, from the frequency offset value sequence, a second frequency offset value of the same type as the first frequency offset value after the first frequency offset value; Determine a second peak-to-average ratio corresponding to the second frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio; A frequency offset value corresponding to the maximum peak-to-average ratio of the first peak-to-average ratio and the second peak-to-average ratio is determined as an initial frequency offset value.

3. The method for determining an initial frequency deviation value according to claim 1, wherein: Determining a frequency offset value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios as an initial frequency offset value comprises: If the first frequency offset value matches the first frequency offset value in the frequency offset value sequence, obtaining a second frequency offset value and a third frequency offset value following the first frequency offset value from the frequency offset value sequence; respectively determining a second peak-to-average ratio corresponding to the second frequency offset value and a third peak-to-average ratio corresponding to the third frequency offset value, wherein the other peak-to-average ratios include the second peak-to-average ratio and the third peak-to-average ratio; A frequency offset value corresponding to a maximum peak-to-average ratio among the first peak-to-average ratio, the second peak-to-average ratio, and the third peak-to-average ratio is determined as an initial frequency offset value.

4. The method for determining an initial frequency deviation value according to claim 1, wherein: Determining whether a first peak-to-average ratio corresponding to the first frequency offset value matches a preset threshold includes: Determine the first peak-to-average ratio corresponding to the first frequency offset value; The first peak-to-average ratio is compared with the preset threshold. If the first peak-to-average ratio is greater than or equal to the preset threshold, it is determined that the first peak-to-average ratio matches the preset threshold; otherwise, it is determined that the first peak-to-average ratio does not match the preset threshold.

5. The method for determining an initial frequency deviation value according to claim 1, wherein: According to the data and indexes of the multiple data blocks in the data frame, the peak-to-average ratio corresponding to each group of sampled data is determined, including: Multiply the data of multiple data blocks in the data frame by the corresponding bits of the data of multiple data blocks after local polarization, take the absolute values ​​and then add them to obtain the peak value corresponding to each group of sampled data; wherein the data of each data block in the data frame is the first synchronization sequence data or the first training sequence data; the data of the multiple data blocks after local polarization refers to the data obtained by performing polarization operation on the data of multiple data blocks in the preset local reference sequence; the data of each data block in the local reference sequence is the second synchronization sequence data or the second training sequence data; Determine the target correlation value sequence corresponding to each group of sampled data according to the index; From before and after the index in the target correlation value sequence, a preset number of correlation values ​​are taken, summed and averaged, and the mean corresponding to each group of sampled data is the mean; The ratio of the peak value to the average value corresponding to each group of sampling data is determined as the peak-to-average ratio.

6. The method for determining an initial frequency deviation value according to claim 1, characterized in that: The method for determining the initial frequency offset value further includes: When it is determined that the first peak-to-average ratio does not match the preset threshold, acquiring a fourth frequency offset value from the remaining frequency offset values ​​in the frequency offset value sequence except the first frequency offset value; Determining whether a fourth peak-to-average ratio corresponding to the fourth frequency offset value matches the preset threshold; When it is determined that the fourth peak-to-average ratio matches the preset threshold, a frequency offset value corresponding to the fourth peak-to-average ratio and a maximum peak-to-average ratio among other peak-to-average ratios is determined as an initial frequency offset value.

7. A device for determining an initial frequency deviation value, characterized in that: include: A preset frequency offset acquisition module, used to acquire a first frequency offset value from a preset frequency offset value sequence, wherein the multiple frequency offset values ​​stored in the frequency offset value sequence are determined according to the bandwidth of the current transmission signal; a peak-to-average ratio analysis module, for determining whether a first peak-to-average ratio corresponding to the first frequency deviation value matches a preset threshold, wherein the first peak-to-average ratio is a ratio between a peak value and an average value of a correlation value corresponding to a current frequency value of the transmission signal, the current frequency value being a frequency value obtained by performing frequency deviation compensation on a transmission frequency value of the transmission signal using the first frequency deviation value, and determining the first peak-to-average ratio corresponding to the first frequency deviation value, comprising: performing frequency deviation compensation on a transmission frequency value of the transmission signal according to the first frequency deviation value to obtain a current frequency value of the transmission signal; sampling the transmission signal at a preset sampling rate within a preset synchronization time; and The method comprises the steps of: performing continuous sampling according to a preset frame structure to obtain a plurality of groups of sampled data; performing windowing on each group of sampled data according to a preset frame structure to obtain a data frame and an index corresponding to each group of sampled data, wherein the data frame includes a plurality of data blocks for performing correlation operations, and the index is used to identify the data starting position of the data frame; determining a peak-to-average ratio corresponding to each group of sampled data according to the data and index of the plurality of data blocks in the data frame, wherein the peak-to-average ratio is a ratio of a peak value to an average value in a correlation value, and the peak value is a correlation value obtained by a correlation operation using data of the plurality of data blocks in the data frame; and determining a maximum peak-to-average ratio among all the peak-to-average ratios as a first peak-to-average ratio corresponding to the first frequency deviation value; An initial frequency deviation determination module is used to determine the frequency deviation value corresponding to the first peak-to-average ratio and the maximum peak-to-average ratio among other peak-to-average ratios as the initial frequency deviation value when it is determined that the first peak-to-average ratio matches the preset threshold, wherein the other peak-to-average ratios are the peak-to-average ratios corresponding to other frequency deviation values ​​in the frequency deviation value sequence except the first frequency deviation value.

8. An electronic device comprising a processor, a communication interface, a memory and a communication bus, wherein: The processor, the communication interface and the memory communicate with each other via the communication bus, wherein: The memory is used to store computer programs; The processor is used to execute the method for determining the initial frequency offset value according to any one of claims 1 to 6 by running the computer program stored in the memory.

9. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, wherein the computer program is configured to execute the method for determining an initial frequency offset value as claimed in any one of claims 1 to 6 when running.

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