Frequency offset correction method and device, product, storage medium, equipment and vehicle

Abstract

The invention relates to a frequency offset correction method and device, a product, a storage medium, equipment and a vehicle, and the method comprises the steps: carrying out the multiple different despreading processing of an original spread spectrum signal, and obtaining a plurality of despreading signals; and performing frequency offset correction processing on the original spread spectrum signal based on the plurality of de-spread signals. The frequency offset correction is carried out according to the plurality of de-spreading signals, so that the plurality of de-spreading signals can be integrated, the characteristics of the signals can be analyzed from different angles, the signal-to-noise ratio threshold effect of the signals is avoided, the frequency offset is estimated more accurately, and the frequency offset correction effect and the effective working range of spread spectrum communication carrier synchronization are improved.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a frequency offset correction method, apparatus, product, storage medium, equipment, and vehicle. Background Art

[0002] Spread spectrum communication is widely used in both military and civilian communications due to its strong anti-interference capabilities. For spread spectrum communication equipment installed on fast-moving terminals, the high speed of movement creates a large dynamic Doppler frequency offset between the transceiver and the receiver. Furthermore, spread spectrum communication is often used in extreme communication environments with low receive power, resulting in a low signal-to-noise ratio (SNR). Therefore, large and rapidly changing frequency offsets and low receive SNRs place stringent demands on the carrier synchronization of spread spectrum communication receivers. Improving the probability of accurately estimating frequency offsets, enabling carrier synchronization in spread spectrum communication, under high dynamic conditions, low SNRs, and without auxiliary data, remains a pressing issue.

[0003] In related technologies, carrier synchronization between transceiver systems is often achieved through a blind estimation algorithm of single-channel or multi-channel cascaded signals. However, this method will produce a threshold effect of the signal-to-noise ratio, cannot correctly estimate the frequency offset, and has a high probability of estimation error. Summary of the Invention

[0004] The embodiments of the present application provide a frequency offset correction method, apparatus, product, storage medium, equipment and vehicle, which can solve the technical problems of low frequency offset estimation accuracy and reduced effective working range of spread spectrum communication carrier synchronization, so as to at least partially solve the above technical problems.

[0005] In order to achieve the above-mentioned object, according to a first aspect of the present application, a frequency offset correction method is provided, the method comprising:

[0006] Performing multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals;

[0007] Based on the multiple despread signals, frequency offset correction processing is performed on the original spread spectrum signal.

[0008] According to a second aspect of the present application, a frequency offset correction device is provided, the device comprising:

[0009] The despreading module is used to perform multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals;

[0010] The correction processing module is used to perform frequency offset correction processing on the original spread spectrum signal based on the multiple despread signals.

[0011] According to a third aspect of the present application, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the above-mentioned frequency offset correction method is implemented.

[0012] According to a fourth aspect of the present application, a computer program product is provided, comprising a computer program, wherein the computer program implements the above-mentioned frequency offset correction method when executed by a processor.

[0013] According to a fifth aspect of the present application, a computer device is provided, comprising a processor and a memory, wherein the memory stores a plurality of instructions; the processor loads instructions from the memory to execute the steps of the frequency offset correction method as described in the first aspect.

[0014] According to a sixth aspect of the present application, a vehicle is provided, comprising the above-mentioned computer device and / or the above-mentioned frequency deviation correction device.

[0015] The frequency offset correction method, apparatus, product, storage medium, device, and vehicle of the embodiments of the present application perform multiple despreading operations on an original spread spectrum signal to obtain multiple despread signals. Frequency offset correction is then performed on the original spread spectrum signal based on the multiple despread signals. Because frequency offset correction is performed based on multiple despread signals, it is possible to combine the multiple despread signals to analyze signal characteristics from different perspectives, avoid signal-to-noise ratio threshold effects, and more accurately estimate frequency offset, thereby improving the frequency offset correction effect and the effective operating range of spread spectrum communication carrier synchronization.

[0016] Other features and advantages of the present application will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] To more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present application. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0018] In order to more completely understand the present application and its beneficial effects, the following description will be given in conjunction with the accompanying drawings, wherein the same drawing numbers represent the same parts in the following description.

[0019] Figure 1 is a flowchart of a frequency offset correction method provided in some embodiments of the present application;

[0020] Figure 2 is a flow chart of a frequency offset correction algorithm provided in some embodiments of the present application;

[0021] Figure 3is a flow chart of a frequency offset correction algorithm provided in other embodiments of the present application;

[0022] Figure 4 Schematic diagram of an effective operating range of spread spectrum communication carrier synchronization of a frequency offset correction scheme and a frequency offset correction scheme based on a single despread signal provided in some embodiments of the present application;

[0023] Figure 5 Schematic diagram showing the relationship between the frequency offset estimation accuracy and the number of parallel channels according to the maximum peak-to-average ratio channel screening principle and the minimum frequency error channel screening principle provided in some embodiments of the present application;

[0024] Figure 6a is a distribution diagram of the frequency offset estimation error root mean square RMS along with the signal-to-noise ratio and the frequency offset size for the single-channel solution and the multi-stage cascade solution provided in some embodiments of the present application. Figure 6b This is a distribution diagram of the frequency offset estimation error root mean square RMS of the frequency offset correction solution in the embodiment of the present application as a function of the signal-to-noise ratio and the frequency offset size;

[0025] Figure 7 is a schematic structural diagram of a frequency offset correction device provided in some embodiments of the present application;

[0026] Figure 8 is a schematic diagram of the structure of a computer device provided in some embodiments of the present application;

[0027] Figure 9 It is a schematic structural diagram of a vehicle provided in some embodiments of the present application. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described 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 those skilled in the art without creative work are within the scope of protection of the present application.

[0029] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0030] In the description of this application, the word "for example" is used to mean "used as an example, illustration or illustration". Any embodiment described in this application as "for example" is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is given to enable any person skilled in the art to implement and use the present invention. In the following description, details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present invention can be implemented without using these specific details. In other examples, well-known structures and processes are not elaborated in detail to avoid obscuring the description of the present invention with unnecessary details. Therefore, the present invention is not intended to be limited to the embodiments shown, but is consistent with the widest scope consistent with the principles and features disclosed in this application.

[0031] In related technologies, carrier synchronization between transceiver systems is achieved by applying a Fast Fourier Transform (FFT) frequency offset estimation algorithm or a backward feedback loop (such as a frequency-locked loop or phase-locked loop) to a single-channel signal. The FFT algorithm is a blind estimation algorithm that does not require redundant pilot information and can directly extract the absolute value of the carrier frequency offset from the communication signal. Above a certain signal-to-noise ratio threshold, the estimation accuracy is independent of the signal-to-noise ratio. Below this threshold, the FFT algorithm cannot accurately estimate the frequency offset. The frequency offset estimation range is directly proportional to the signal sampling rate used in the FFT operation. For spread-spectrum communication systems, despreading can achieve a certain signal-to-noise ratio gain, effectively lowering the system's signal-to-noise ratio threshold. However, despreading significantly reduces the signal sampling rate, thereby reducing the effective range of frequency offset estimation. For spread-spectrum systems with large dynamic range and low signal-to-noise ratio, there is a high probability of estimation error whether using raw data or despread data for frequency offset estimation.

[0032] On the other hand, carrier synchronization between the transmitting and receiving systems is achieved by cascading multiple signals at multiple levels, using a Fast Fourier Transform (FFT) frequency offset estimation algorithm or a backward feedback loop (such as a frequency-locked loop, a phase-locked loop, etc.). For a multi-level cascade solution, if the signal-to-noise ratio of the signal entering the first-level system is too low, errors will occur in all subsequent cascaded systems.

[0033] To address the aforementioned issues, embodiments of the present application provide a frequency offset correction method. This method performs multiple despreading operations on an original spread-spectrum signal to obtain multiple despread signals. Frequency offset correction is then performed on the original spread-spectrum signal based on the multiple despread signals. Because frequency offset correction is performed based on multiple despread signals, it is possible to combine multiple despread signals and analyze signal characteristics from different perspectives, avoiding signal-to-noise ratio threshold effects and more accurately estimating frequency offset. This improves the effectiveness of frequency offset correction and the effective operating range of carrier synchronization in spread-spectrum communications.

[0034] See also Figure 1 , provides a frequency offset correction method, which is applied to a computer device. The computer device may be a terminal device or a server. The method includes:

[0035] Step S101: perform multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals.

[0036] The original spread spectrum signal in this embodiment is the un-despread spread spectrum signal received by the computer device. For example, the expression of the original spread spectrum signal is y(n)=y I (n)+jy Q (n), where y(n) represents the received discrete signal, y I (n) represents the in-phase signal component, y Q (n) represents the orthogonal signal component, n represents the discrete index value of the discrete signal, and j is the imaginary unit.

[0037] Spread spectrum communication is a technology that transmits information by spreading the signal's spectrum to a frequency band wider than the original information bandwidth. This technology can improve the signal's ability to resist interference and increase communication security.

[0038] Despreading is the inverse process of spread spectrum, which is to restore the expanded spectrum to the original narrow bandwidth. This is usually achieved by performing correlation operations with the original spreading code. Multiple despreading can be achieved by using multiple truncation codes corresponding to the same spreading code. The despread signal is the signal obtained by multiplying and accumulating the corresponding terms of the original spread spectrum signal with a spreading code used for despreading and averaging them. For example, if the spreading code length is 8, [1,-1,1,-1,1,-1,1,-1]. If 8 times full despreading is performed, [1,-1,1,-1,1,-1,1,-1] is used to despread to obtain one data symbol. If 4 times partial despreading is performed, [1,-1,1,-1] is used to despread twice to obtain two data symbols.

[0039] Specifically, the computer device performs multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals, thereby realizing multi-path parallel despreading of the original spread spectrum signal, so as to subsequently perform frequency offset estimation based on the multiple despread signals.

[0040] In some embodiments, performing multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals includes: performing multiple despreading processes on the original spread spectrum signal according to multiple preset spreading factors to obtain multiple despread signals.

[0041] Among them, multiple preset spreading factors can be based on the spreading factors of the spreading codes agreed upon by the transceiver. In some embodiments, the bases of the different preset spreading factors are the same, but the exponents are different. For example, a set of specified multiples of the received signal is performed based on the spreading codes agreed upon by the transceiver. l-way despreading, each despreading branch i has a different spreading gain Multiple preset spreading factors are Its base is 2, and the exponents are M1, M2, M3…, M l In a specific embodiment, the partially despread i-th multiplexed signal is y i (n) is the despread signal of the i-th despread branch.

[0042] Specifically, the original spread spectrum signal is despread multiple times according to multiple preset spreading factors. Each despreading step generates a despread signal, resulting in multiple despread signals. These despread signals exhibit different characteristics due to the different spreading factors, such as different signal-to-noise ratios, different symbol sampling rates, and different frequency offset estimation results. This allows the subsequent use of multiple despread signals for frequency offset estimation, improving the accuracy of frequency offset estimation.

[0043] Step S102: performing frequency offset correction processing on the original spread spectrum signal based on the multiple despread signals.

[0044] Specifically, a frequency offset correction value can be determined based on multiple despread signals, and frequency offset correction processing can be performed on the original spread spectrum signal according to the determined frequency offset correction value. It can be understood that in this embodiment, by integrating information from multiple despread signals and analyzing signal characteristics from different perspectives, the signal-to-noise ratio threshold effect is avoided, frequency offset is estimated more accurately, and the frequency offset correction effect and the effective operating range of spread spectrum communication carrier synchronization are improved.

[0045] In some embodiments, the frequency offset correction processing is performed on the original spread spectrum signal based on multiple demodulated signals, including: determining the frequency offset estimation result of each demodulated signal; and performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset estimation result of each demodulated signal.

[0046] The frequency offset estimation result refers to a frequency offset result obtained by analyzing a single despread signal.

[0047] Specifically, the frequency offset estimation result of each demodulated signal can be determined by frequency offset estimation based on FFT, frequency offset estimation based on autocorrelation function, or frequency offset estimation based on phase difference, thereby effectively determining the frequency offset estimation result of each demodulated signal. Then, based on the frequency offset estimation result of each demodulated signal, the original spread spectrum signal is subjected to frequency offset correction processing, thereby improving the frequency offset correction effect and the effective working range of spread spectrum communication carrier synchronization.

[0048] In some embodiments, determining the frequency offset estimation result of each of the despread signals includes: determining the frequency offset estimation result of each of the despread signals through a Fourier transform processing algorithm.

[0049] The Fourier transform processing algorithm may be an FFT algorithm.

[0050] Specifically, an FFT transform can be performed on each despread signal to analyze its spectrum. The main components of the spectrum can then be identified to determine the frequency offset estimation result. Because the FFT transform converts the signal from the time domain to the frequency domain, the frequency offset appears as a shift in the spectral line in the frequency domain. This allows the magnitude of the frequency offset to be estimated, and the frequency offset estimation result for each despread signal can be determined.

[0051] In some embodiments, the frequency deviation estimation result of each of the demodulated signals is determined by a Fourier transform processing algorithm, including: performing demodulation processing on each of the demodulated signals based on demodulation parameters; and performing Fourier transform processing on the demodulated signals to obtain a frequency deviation estimation result.

[0052] The demodulation parameter refers to a parameter used to perform demodulation processing on the despread signal, which may be a modulation order, and the modulation order is greater than 2.

[0053] Specifically, based on the demodulation parameters, each despread signal is demodulated and Fourier transformed to obtain a frequency offset estimation result. As can be understood, since demodulation can remove the modulation effect of the signal, Fourier transforming the despread signal after demodulation ensures that the estimated frequency offset result is accurate.

[0054] In some embodiments, the demodulating each of the despread signals based on the demodulation parameters includes: multiplying each of the despread signals with itself multiple times based on the demodulation parameters to achieve demodulation.

[0055] Specifically, each despread signal is multiplied by itself multiple times based on the demodulation parameters, thereby filtering out the influence of the changes in the modulation symbols themselves, thereby ensuring that the frequency offset estimation result is accurate and reasonable.

[0056] In a specific embodiment, the demodulation parameter is the modulation order m, and m is greater than 1, then the m-th power operation of each despread signal can be calculated, such as (y i (n)) m , filtering out the impact of changes in the modulation symbols themselves.

[0057] |Y i (k)|=|FFT[y i (n)) m ]|;

[0058] Among them, |Y i (k)| represents the despread signal y i (n), k is the discrete index of discrete Fourier transform. For example, for a signal y(n) with a length of 128, k is an integer from 0 to 127.

[0059] In some embodiments, the frequency offset correction processing is performed on the original spread spectrum signal based on the frequency offset estimation result of each of the demodulated signals, including: determining the frequency offset correction value of the original spread spectrum signal based on the frequency offset estimation result of each of the demodulated signals; and performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset correction value.

[0060] The frequency offset correction value refers to a correction value for correcting the frequency offset of the original spread spectrum signal.

[0061] Specifically, the frequency offset estimation results of each despread signal can be compared and analyzed to determine the optimal frequency offset estimation result. A frequency offset correction value can be determined based on the optimal frequency offset estimation result, and frequency offset correction processing can be performed on the original spread spectrum signal based on the frequency offset correction value. It can be understood that in this embodiment, by comprehensively analyzing the frequency offset estimation results of each despread signal, the frequency offset estimation results of multiple despread signals can be effectively utilized to improve the frequency offset correction accuracy of the original spread spectrum signal, thereby enhancing the reliability and stability of the spread spectrum system.

[0062] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the frequency offset estimation result of each of the demodulated signals includes: determining the demodulation result indication information of each of the demodulated signals based on the frequency offset estimation result of each of the demodulated signals; and determining the frequency offset correction value of the original spread spectrum signal based on the demodulation result indication information.

[0063] The despreading result indication information is index information for indicating the despreading quality of the despread signal, and is used as an index for the quality of the despread signal. The frequency offset estimation result of each despread signal is then evaluated based on the despreading result indication information.

[0064] Specifically, based on the frequency offset estimation results of each despread signal, the peak-to-average frequency ratio (PAPR), signal-to-noise ratio (SNR), error vector magnitude (EVM), signal quality indicators, etc. of the frequency offset estimation results can be analyzed to determine despreading result indication information for each despread signal. Then, based on the despreading result indication information, the frequency offset correction value of the original spread spectrum signal can be determined. It is understandable that in the case of low signal-to-noise ratio or large frequency offset, by comprehensively analyzing the despreading result indication information of multiple despread signals to determine the frequency offset correction value, the frequency offset estimation range is expanded, the signal-to-noise ratio threshold effect of the signal is avoided, the robustness of spread spectrum communication is enhanced, and the performance and reliability of the communication system are improved.

[0065] In some embodiments, determining the demodulation result indication information of each demodulation signal based on the frequency deviation estimation result of each demodulation signal includes: determining the frequency deviation statistical characteristic information corresponding to each demodulation signal based on the frequency deviation estimation result of each demodulation signal; and determining the demodulation result indication information of each demodulation signal based on the frequency deviation statistical characteristic information corresponding to each demodulation signal.

[0066] The frequency deviation statistical feature information is statistical result information representing frequency deviation characteristics, including but not limited to mean, variance, peak, median, deviation, etc. In some embodiments, the frequency deviation statistical feature information includes signal peak value and / or signal mean value.

[0067] Among them, the signal peak refers to the peak value of the frequency deviation sinusoidal frequency signal in the frequency deviation estimation result; the signal mean refers to the average value of the frequency deviation sinusoidal frequency signal, among which the signal peak max|Y i (k)|The expression is as follows:

[0068]

[0069] in, The function represents the function variable |Y following max i (k)|The subscript value when it is maximum is the FFT result|FFT[(y i (n)) m ]| is the value of k when the absolute value of |Y is the largest, that is, i (k)|The peak position of the

[0070] Among them, the signal mean mean|Y i (K)|The expression is as follows:

[0071]

[0072] Specifically, based on the frequency offset statistical characteristic information corresponding to each despread signal, the despreading result indication information for each despread signal is determined. This can be determined based on the signal peak value and signal mean value. Because the frequency offset statistical characteristic information can reflect the strength and stability of the signal, by analyzing the signal peak value and mean value in the frequency offset statistical characteristic information, the despreading quality can be more accurately assessed, thereby improving the rationality and accuracy of the despreading result indication information for each despread signal.

[0073] In some embodiments, the demodulation result indication information of each demodulation signal is determined based on the frequency deviation statistical characteristic information corresponding to each demodulation signal, including: dividing the signal peak value corresponding to each demodulation signal by its corresponding signal mean value to obtain the demodulation result indication information of each demodulation signal; or dividing the signal mean value corresponding to each demodulation signal by its corresponding signal peak value to obtain the demodulation result indication information of each demodulation signal.

[0074] Specifically, the signal peak value corresponding to each despread signal can be divided by its corresponding signal mean value to serve as the despreading result indication information of each despread signal, or the signal mean value corresponding to each despread signal can be divided by its corresponding signal peak value to serve as the despreading result indication information of each despread signal. That is, the despreading result indication information of each despread signal can be a peak-to-average ratio or the inverse of the peak-to-average ratio. It can be understood that since the signal peak value and the signal mean value reflect the reliability of the signal analysis to a certain extent, determining the peak-to-average ratio or the inverse of the peak-to-average ratio as the despreading result indication information of each despread signal can improve the rationality and accuracy of the despreading result indication information of each despread signal.

[0075] For example, the despreading result indication information is the peak-to-average ratio, and the despreading result indication information PAPR i The expression is as follows:

[0076]

[0077] Among them, max|Y i (k)| is the signal peak value, mean|Y i (k)| is the signal mean.

[0078] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the demodulation result indication information includes: determining a target frequency offset estimation result from the frequency offset estimation results of each of the demodulation signals based on the demodulation result indication information; and determining the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result.

[0079] The target frequency offset estimation result is the optimal or suboptimal frequency offset estimation result among the frequency offset estimation results of each despread signal.

[0080] Specifically, the optimal or suboptimal despreading result indication information can be selected from the despreading result indication information, and a target frequency offset estimation result can be determined based on the corresponding frequency offset estimation result in the selected optimal or suboptimal despreading result indication information. Then, the frequency offset correction value of the original spread spectrum signal can be determined based on the target frequency offset estimation result. It can be understood that because the despreading result indication information can characterize the quality of the despreading result, determining the target frequency offset estimation result from the frequency offset estimation results of each despread signal based on the despreading result indication information can improve the rationality and accuracy of the target frequency offset estimation result, thereby improving the accuracy of the frequency offset correction value.

[0081] In some embodiments, the target frequency offset estimation result is determined from the frequency offset estimation result of each demodulated signal based on the demodulation result indication information, including: when the demodulation result indication information is obtained according to the signal peak value divided by the signal mean value, the frequency offset estimation result of the demodulated signal corresponding to the maximum demodulation result indication information is determined as the target frequency offset estimation result, or, when the demodulation result indication information is obtained according to the signal mean value divided by the signal peak value, the frequency offset estimation result of the demodulated signal corresponding to the minimum demodulation result indication information is determined as the target frequency offset estimation result.

[0082] Specifically, when the demodulation result indication information is the signal peak divided by the signal mean, the maximum demodulation result indication information, that is, the maximum peak-to-average ratio, is selected as the target frequency deviation estimation result; or, when the demodulation result indication information is the mean signal divided by the signal peak, the minimum demodulation result indication information, that is, the minimum inverse of the peak-to-average ratio, is selected as the target frequency deviation estimation result. It can be understood that the peak-to-average ratio characterizes the ratio of the sinusoidal frequency signal (peak) and the background noise (mean) in the FFT result after different multiples of demodulation and FFT operation, and to a certain extent reflects the reliability of the signal analysis. The larger the peak-to-average ratio, the higher the reliability of the signal. Therefore, the frequency deviation estimation result of the demodulation signal corresponding to the maximum peak-to-average ratio is determined as the target frequency deviation estimation result to ensure the rationality and accuracy of the target frequency deviation estimation result.

[0083] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result includes: determining the frequency offset correction value of the original spread spectrum signal according to the target frequency offset estimation result, the transmission parameters of the demodulated signal, and the Fourier transform parameters of the demodulated signal.

[0084] The transmission parameter of the despread signal may be the symbol rate of the despread signal. The Fourier transform parameter of the despread signal may be the number N of Fourier transform points.

[0085] Specifically, the frequency offset correction value for the original spread spectrum signal can be determined based on the target frequency offset estimation result, the transmission parameters of the despread signal, and the Fourier transform parameters of the despread signal. Because the target frequency offset estimation result has high accuracy, determining the frequency offset correction value based on the target frequency offset estimation result can ensure high accuracy of the frequency offset correction value.

[0086] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result, the transmission parameters of the demodulated signal, and the Fourier transform parameters of the demodulated signal includes: determining the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result, the transmission parameters of the demodulated signal, the Fourier transform parameters of the demodulated signal, and the demodulation parameters of the demodulated signal.

[0087] The demodulation parameter of the despread signal may be a modulation order. For example, the calculation of the demodulation parameter based on the despread signal may be divided by the demodulation parameter.

[0088] Specifically, the frequency offset correction value can be determined based on the target frequency offset estimation result, the transmission parameters of the despread signal, the Fourier transform parameters of the despread signal, and the demodulation parameters of the despread signal. It can be understood that in this embodiment, the accuracy of the frequency offset correction value is further improved by combining the target frequency offset estimation result with the demodulation parameters of the despread signal.

[0089] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result, the transmission parameters of the demodulated signal, the Fourier transform parameters of the demodulated signal, and the demodulation parameters of the demodulated signal includes: determining a first ratio based on the transmission parameters of the demodulated signal, the Fourier transform parameters of the demodulated signal, and the demodulation parameters of the demodulated signal; and determining the frequency offset correction value of the original spread spectrum signal based on the first ratio and the target frequency offset estimation result.

[0090] The first ratio may be determined based on the transmission parameters of the despread signal, the Fourier transform parameters of the despread signal, and the demodulation parameters of the despread signal. For example, the calculation formula of the first ratio Z1 is as follows:

[0091]

[0092] in, is the symbol rate of the despread signal, N is the Fourier transform parameter of the despread signal, such as the number of Fourier transform points N, and m is the demodulation parameter, such as the modulation order.

[0093] Specifically, a first ratio is determined based on transmission parameters of the despread signal, Fourier transform parameters of the despread signal, and demodulation parameters of the despread signal. A frequency offset correction value for the original spread spectrum signal is determined based on the first ratio and a target frequency offset estimation result. Because the calculation of the first ratio takes the demodulation parameters into account, the accuracy of the first ratio is improved. Therefore, determining the frequency offset correction value based on the first ratio and the target frequency offset estimation result can increase the probability of correctly estimating the frequency offset.

[0094] In some embodiments, determining the frequency offset correction value of the original spread spectrum signal based on the first ratio and the target frequency offset estimation result includes: multiplying the first ratio by the peak value in the target frequency offset estimation result to obtain the frequency offset correction value of the original spread spectrum signal.

[0095] The peak value in the target frequency offset estimation result is the signal peak value in the target frequency offset estimation result. For example, the target frequency offset estimation result is the maximum peak-to-average ratio PAPR. i The frequency offset estimation result of the corresponding despread signal, that is, the frequency offset estimation result of the despread signal corresponding to the despread signal of the i-th despread branch, at this time, the signal peak value in the target frequency offset estimation result is max|Y i That is, the frequency offset correction value is determined based on the despread signal of the i-th despread branch.

[0096] Specifically, the first ratio is multiplied by the peak value in the target frequency offset estimation result to obtain the frequency offset correction value. It can be understood that since the frequency offset correction value is determined based on the peak value in the target frequency offset estimation result, the accuracy of the frequency offset correction value can be improved.

[0097] In one embodiment, the frequency offset correction value Δf opt The calculation formula is as follows:

[0098]

[0099] Where Δf i is the frequency offset correction value.

[0100] In the above formula, the influence of the modulation symbol itself is filtered out by the m-th power operation, and then y is calculated. i The FFT peak spectrum line of the m-th power signal of (n) corresponds to a frequency that is m times the frequency deviation.

[0101] In some embodiments, performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset correction value includes: determining a frequency offset compensation value based on the frequency offset correction value; and performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset compensation value.

[0102] The frequency offset compensation value is a frequency value used to compensate the original spread spectrum signal. In some embodiments, determining the frequency offset compensation value based on the frequency offset correction value includes: determining a complex value based on the frequency offset correction value; and performing negative power processing on the complex value to obtain the frequency offset compensation value.

[0103] Specifically, a complex value may be determined based on the frequency offset correction value, and the complex value may be subjected to negative power processing to obtain a frequency offset compensation value. For example, the frequency offset compensation value h may be calculated using the following formula:

[0104]

[0105] Where j2πΔf opt Expressed as a complex value, the complex value is raised to a negative power to obtain -j2πΔf opt .

[0106] Specifically, a frequency offset compensation value is determined based on the frequency offset correction value, and then the frequency offset of the original spread spectrum signal is corrected based on the frequency offset compensation value. It can be understood that because the frequency offset correction value has a high accuracy, the frequency offset compensation value also has a high accuracy. Therefore, the frequency offset correction of the original spread spectrum signal based on the frequency offset compensation value can reduce the frequency offset of the original spread spectrum signal, facilitating subsequent further frequency offset correction processing.

[0107] In some embodiments, the frequency offset correction processing of the original spread spectrum signal based on the frequency offset compensation value includes: performing a first frequency offset correction processing on the original spread spectrum signal based on the frequency offset compensation value to obtain a corrected signal; performing despreading processing on the corrected signal to obtain a target despread signal; and performing a second frequency offset correction processing on the target despread signal to achieve frequency offset correction processing on the original spread spectrum signal.

[0108] Among them, in some embodiments, the first frequency offset correction processing is performed on the original spread spectrum signal based on the frequency offset compensation value to obtain a corrected signal, including: multiplying the frequency offset compensation value by the original spread spectrum signal to achieve the first frequency offset correction processing of the original spread spectrum signal to obtain a corrected signal.

[0109] Specifically, based on the frequency offset compensation value, the original spread spectrum signal is subjected to a first frequency offset correction process to obtain a corrected signal, and then the corrected signal is demodulated to obtain a target demodulated signal, and finally the target demodulated signal is subjected to a second frequency offset correction process to achieve frequency offset correction of the original spread spectrum signal.

[0110] In one embodiment, the corrected signal is calculated using the following formula:

[0111] z I (n) = yI (n)*cos(2πΔf opt n / f sym )+y Q (n)*sin(2πΔf opt n / f sym )

[0112] z Q (n) = y Q (n)*cos(2πΔf opt n / f sym )-y I (n)*sin(2πΔf opt n / f sym )

[0113] Among them, z I (n), z Q (n) is the I-channel and Q-channel signals in the corrected signal.

[0114] Then, the corrected signal is despread to obtain the target despread signal. The corrected signal can be completely despread by a preset spreading factor to obtain the target despread signal s(n)=s1(k)+js Q (k), then, a second frequency offset correction process is performed on the target despread signal s(n) to achieve frequency offset correction of the original spread spectrum signal.

[0115] In some embodiments, the second frequency offset correction processing is performed on the target demodulated signal to achieve frequency offset correction processing on the original spread spectrum signal, including: performing a second frequency offset correction processing on the target demodulated signal through at least one algorithm selected from a frequency locked loop, a phase locked loop, a Fitts algorithm, a left-right algorithm, and an autocorrelation function algorithm to achieve frequency offset correction processing on the original spread spectrum signal.

[0116] Specifically, the target demodulated signal can be subjected to a second frequency deviation correction process by using at least one of a frequency-locked loop, a phase-locked loop, a Fitz algorithm, a left-right algorithm (L&R algorithm), and an autocorrelation function algorithm, thereby achieving further correction of the original spread spectrum signal and further reducing the frequency deviation to a receivable level.

[0117] In some embodiments, the method further includes: performing decoding processing and / or demodulation processing on the signal after the second frequency offset correction processing.

[0118] Specifically, the signal after the second frequency offset correction processing is decoded and / or demodulated. Since the signal after the second frequency offset correction processing is a relatively accurate signal, the signal after the second frequency offset correction processing is decoded and / or demodulated, so as to obtain valid data information and improve signal processing efficiency.

[0119] In one embodiment, Figure 2 and Figure 3 As shown in FIG. 1 , a flow chart of a frequency offset correction algorithm in an embodiment of the present application is shown in FIG. Figure 2 As shown, it includes partial despreading, FFT frequency offset estimation, frequency offset channel selection, coarse frequency offset correction, and fine frequency offset correction.

[0120] Specifically, the present application uses a multi-channel parallel two-stage estimation scheme. First, in the FFT frequency deviation rough estimation module, multi-channel parallel partial despread signals with different despreading multiples are used for FFT frequency deviation estimation to obtain multi-channel frequency deviation estimation results; rough estimation channel selection is performed, and the channel with the largest peak-to-average value in the FFT result is selected as the optimal result of frequency deviation estimation, and the result after frequency deviation correction of the channel is output to the fine estimation module. Since the corrected frequency deviation is relatively small, the module can use a phase-locked loop or a frequency-locked loop to achieve rapid convergence, and the signal after fine estimation is used for subsequent receiving and processing modules, such as demodulation, decoding, etc. Figure 3 As shown, the following steps are included:

[0121] Step S01, the undespread signal after the front-end receiving and processing step is input;

[0122] Step S02: The received signal is multiplied by a specified number based on the spread spectrum code agreed upon by the transmitting and receiving ends. l-way despreading, each despreading branch i has a different spreading gain and sampling rate It can be used to correct the received signal corresponding to the frequency deviation range and signal-to-noise ratio;

[0123] Step S03, frequency offset correction is performed on each of the l-way partially despread signals using an FFT frequency offset estimation algorithm. Suppose the i-th complex signal after partial despreading is

[0124] Step S04, calculating the peak-to-average ratio of l-channel FFT results, and selecting the channel with the largest peak-to-average ratio as the optimal frequency offset estimation result;

[0125] Step S05, performing coarse frequency offset correction according to the selected FFT frequency offset estimation result;

[0126] In step S06, the corrected and despread signal is sent to a frequency-locked loop / phase-locked loop for precise frequency deviation correction, thereby further reducing the frequency deviation to a level that allows for correct reception.

[0127] Compared with the prior art, the embodiments of the present application greatly improve the effective operating range of carrier synchronization in the coarse estimation stage, avoid signal errors in certain scenarios with low signal-to-noise ratio but not large frequency deviation or certain scenarios with large frequency deviation but high signal-to-noise ratio, and can significantly improve the probability of the system correctly estimating the frequency deviation and reduce abnormal interruptions in the spread spectrum communication system.

[0128] In a specific embodiment, MATLAB simulation experiments are used to analyze experimental results of the frequency offset correction scheme in the embodiment of the present application and the frequency offset correction scheme based on a single despread signal or a cascade of single despread signals.

[0129] First, the effective frequency offset estimation range and the minimum signal-to-noise ratio threshold corresponding to the despreading multiples of different despreading factors are given in the case of π / 4-QPSK modulation, as shown in Table 1.

[0130] Table 1: Frequency offset effective estimation range and minimum signal-to-noise ratio threshold corresponding to different despreading factors

[0131] Despreading multiple Minimum signal-to-noise ratio threshold (dB) Frequency offset estimation range (kHz) 1 1 2000 2 0 1000 4 -2 500 8 -4 250 16 -6 125 32 -8 62.5 64 -10 31.25 128 -13 15.625

[0132] Among them, the simulation 1 condition settings are: the symbol rate is set to 8Mbps, the spreading factor is 128, the spreading code uses a 128-length Gold pseudo-random code, the noise is Gaussian additive white noise, and the number of data symbols used for FFT calculation is 64. The effective frequency offset estimation range is defined as the maximum absolute value of the frequency offset value that can correctly estimate the true frequency offset approximation through the FFT frequency offset estimation algorithm. The m value in the FFT calculation expression corresponding to QPSK is 4, and it is easy to obtain its maximum effective estimation range is The minimum SNR threshold is defined as the minimum SNR value where the RMS error between the estimated frequency offset and the actual frequency offset does not exceed a certain frequency offset value. The frequency offset used to simulate the SNR threshold is set to 5 kHz, the number of simulation statistics is set to 1000, the RMS error does not exceed 500 Hz, and the SNR traversal step size is 1 dB. The simulation results show that as the despreading factor increases, the SNR threshold gradually decreases, and the frequency offset estimation range gradually narrows.

[0133] Based on this, we can theoretically and qualitatively analyze the rationality of selecting the optimal channel based on the maximum peak-to-average ratio (PAR), that is, the target frequency offset. When the signal frequency offset is large but the signal-to-noise ratio (SNR) is relatively high, the frequency offset significantly exceeds the symbol rate (the higher the symbol rate, the more difficult the frequency offset estimation). This means that the chip sample phase fluctuates within a complete despreading cycle. Despreading cannot achieve a good SNR gain and instead introduces a large amount of additional noise. In this case, the PAR of the signal with a low despreading factor is high, while the PAR of the signal with a high despreading factor is low. Based on the trend in the table, the FFT estimation result with a lower despreading factor (i.e., the one with a higher PAR) should be selected. When the signal frequency offset is small but the SNR is low, the chip sample phase fluctuation within a complete despreading cycle is minimal, and despreading can achieve a higher SNR gain. Therefore, the PAR of the signal with a low despreading factor is low, while the PAR of the signal with a high despreading factor is high. Based on the trend in the table, the FFT estimation result with a higher PAR should be selected. According to the above analysis, the optimal or suboptimal frequency offset correction result can be selected by maximizing the peak-to-average ratio principle. In particular, this scheme does not require any pilot assistance and can be directly extracted from the communication data, which is suitable for the pilot-free data frame characteristics of the FFT blind estimation algorithm.

[0134] like Figure 4 FIG. 1 is a schematic diagram of an effective operating range of a spread spectrum communication carrier synchronization for a frequency offset correction scheme and a frequency offset correction scheme based on a single despread signal in an embodiment of the present application, Figure 4 It can be seen that in the embodiment of the present application, based on multiple despread signals, the frequency offset-SNR area that could not be correctly estimated before is reduced, and the probability of communication data loss or error caused by too low SNR or too large frequency offset in the communication system is further reduced.

[0135] Monte Carlo simulations were performed using MATLAB to verify the rationality of the maximum peak-to-average ratio screening principle and the communication performance gain brought by the scheme of multiple despread signals (multi-channel parallel scheme). Simulation 2 condition settings: 1000 random experiments were performed, each random experiment generated a random signal-to-noise ratio and initial frequency offset, the signal-to-noise ratio SNR obeyed the distribution U(-10, 0), the initial frequency offset size Δf satisfied, P Δf =lg(Δf / f0)~U(-5,0), the number of parallel channels for frequency offset estimation n ranges from 1 to 8, and the corresponding partial despreading factors are the first n values of [1, 2, 4, 8, 16, 32, 64, 128]. The remaining parameters are the same as those in Simulation 1. The frequency offset estimation is correct when the difference between the estimated frequency offset and the actual frequency offset is less than 2 kHz.

[0136] Define the minimum frequency error channel screening principle: select the parallel channel with the smallest absolute difference between the actual frequency deviation and the channel as the optimal estimate. This principle cannot be applied in practice and is only used as a control group for ideal performance simulations. Figure 5 Figure 2 is a diagram showing the relationship between the frequency offset estimation accuracy of the maximum peak-to-average ratio channel screening principle and the minimum frequency error channel screening principle as the number of parallel channels changes under the simulated distribution conditions. Figure 5 It can be seen that as the number of parallel channels increases, the success probability of frequency offset estimation increases significantly, indicating that the parallel scheme proposed in this patent can bring more obvious performance gains, and the performance of the maximum peak-to-average ratio principle is close to the ideal performance, and the rationality of this criterion has been verified.

[0137] In addition, another indicator to measure system performance is the root mean square (RMS) of the frequency error signal after the system has undergone the first-stage coarse frequency offset correction. This is used to measure the effectiveness of the coarse frequency offset correction. The smaller the RMS, the better the correction effect. When the RMS exceeds the ability of the subsequent fine frequency offset correction, the frequency offset correction cannot be performed correctly. Through MATLAB simulation, the distribution of the RMS of the coarse frequency offset estimation error of the parallel scheme proposed in this patent relative to the traditional scheme with the signal-to-noise ratio and the frequency offset size can be given, as shown in the figure below: Figure 6a As shown in Figure 2, the frequency offset estimation error root mean square (RMS) distribution of the single-channel solution and the multi-stage cascade solution changes with the signal-to-noise ratio and the frequency offset size. Figure 6b This is a distribution diagram of the frequency offset estimation error root mean square RMS of the frequency offset correction solution in the embodiment of the present application as a function of the signal-to-noise ratio and the frequency offset size.

[0138] Here, it is assumed that both the first-stage frequency offset correction in the multi-stage cascade scheme and the single-channel scheme 1 use an unspread signal for frequency offset estimation. It can be seen that in most cases, traditional schemes cannot correctly perform subsequent frequency offset correction. However, the parallel scheme proposed in this patent achieves a smaller RMS frequency offset estimation error than traditional schemes, does not affect the functionality of the subsequent fine frequency offset module, and extends the operating range of the spread spectrum communication system.

[0139] The frequency offset correction method described above performs multiple despreading operations on the original spread-spectrum signal to generate multiple despread signals. Frequency offset correction is then performed on the original spread-spectrum signal based on these multiple despread signals. Since frequency offset correction is performed based on multiple despread signals, it is possible to combine these multiple despread signals and analyze signal characteristics from different perspectives, thus avoiding signal-to-noise ratio threshold effects and more accurately estimating frequency offset. This improves the frequency offset correction effectiveness and the effective operating range of spread-spectrum communication carrier synchronization.

[0140] It should be understood that, although the steps in the flowcharts of the above embodiments are shown in sequence as indicated by the arrows, these steps are not necessarily performed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be performed in other orders. Moreover, at least a portion of the steps in the flowcharts of the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily performed at the same time, but can be performed at different times. The execution order of these steps or stages is not necessarily to be performed in sequence, but can be performed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0141] Based on the same inventive concept, this application also provides a frequency offset correction device for implementing the frequency offset correction method described in the aforementioned embodiment where a computer device is the execution subject. The implementation solution provided by this device is similar to the implementation solution described in the aforementioned method. Therefore, the specific limitations in one or more of the frequency offset correction device embodiments provided below can be found in the above-mentioned limitations on the frequency offset correction method described in the embodiment where a computer device is the execution subject, and will not be further elaborated here.

[0142] In some embodiments, as Figure 7 As shown, a frequency offset correction device is provided, which can be integrated into a computer device, including:

[0143] Despreading module 701 and correction processing module 702, wherein:

[0144] The despreading module 701 is configured to perform multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals;

[0145] The correction processing module 702 is configured to perform frequency offset correction processing on the original spread spectrum signal based on the multiple despread signals.

[0146] In some embodiments, the correction processing module 702 is specifically configured to determine a frequency offset estimation result of each of the despread signals; and perform frequency offset correction processing on the original spread spectrum signal based on the frequency offset estimation result of each of the despread signals.

[0147] In some embodiments, the correction processing module 702 is further configured to determine a frequency offset correction value of the original spread spectrum signal based on the frequency offset estimation result of each of the despread signals; and perform frequency offset correction processing on the original spread spectrum signal based on the frequency offset correction value.

[0148] In some embodiments, the correction processing module 702 is further specifically used to determine the demodulation result indication information of each demodulation signal based on the frequency offset estimation result of each demodulation signal; and determine the frequency offset correction value of the original spread spectrum signal based on the demodulation result indication information.

[0149] In some embodiments, the correction processing module 702 is further specifically used to determine the frequency deviation statistical characteristic information corresponding to each of the demodulated signals based on the frequency deviation estimation result of each of the demodulated signals; and to determine the demodulation result indication information of each of the demodulated signals based on the frequency deviation statistical characteristic information corresponding to each of the demodulated signals.

[0150] In some embodiments, the frequency deviation statistical characteristic information includes a signal peak value and / or a signal mean value.

[0151] In some embodiments, the correction processing module 702 is specifically used to divide the signal peak value corresponding to each of the demodulated signals by its corresponding signal mean value to obtain the demodulation result indication information of each of the demodulated signals; or, divide the signal mean value corresponding to each of the demodulated signals by its corresponding signal peak value to obtain the demodulation result indication information of each of the demodulated signals.

[0152] In some embodiments, the correction processing module 702 is further configured to determine a target frequency offset estimation result from the frequency offset estimation results of each of the demodulated signals based on the demodulation result indication information; and determine a frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result.

[0153] In some embodiments, the correction processing module 702 is specifically further used to determine the frequency deviation estimation result of the demodulated signal corresponding to the maximum demodulated result indication information as the target frequency deviation estimation result when the demodulated result indication information is obtained by dividing the signal peak value by the signal mean value, or to determine the frequency deviation estimation result of the demodulated signal corresponding to the minimum demodulated result indication information as the target frequency deviation estimation result when the demodulated result indication information is obtained by dividing the signal mean value by the signal peak value.

[0154] In some embodiments, the correction processing module 702 is further configured to determine a frequency offset correction value of the original spread spectrum signal according to the target frequency offset estimation result, the transmission parameters of the despread signal, and the Fourier transform parameters of the despread signal.

[0155] In some embodiments, the correction processing module 702 is specifically used to determine the frequency offset correction value of the original spread spectrum signal based on the target frequency offset estimation result, the transmission parameters of the demodulated signal, the Fourier transform parameters of the demodulated signal, and the demodulation parameters of the demodulated signal.

[0156] In some embodiments, the correction processing module 702 is specifically used to determine a first ratio based on the transmission parameters of the demodulated signal, the Fourier transform parameters of the demodulated signal, and the demodulation parameters of the demodulated signal; and determine the frequency deviation correction value of the original spread spectrum signal based on the first ratio and the target frequency deviation estimation result.

[0157] In some embodiments, the correction processing module 702 is further configured to multiply the first ratio by a peak value in the target frequency offset estimation result to obtain a frequency offset correction value of the original spread spectrum signal.

[0158] In some embodiments, the correction processing module 702 is further configured to determine a frequency offset compensation value based on the frequency offset correction value; and perform frequency offset correction processing on the original spread spectrum signal based on the frequency offset compensation value.

[0159] In some embodiments, the correction processing module 702 is further configured to determine a complex value based on the frequency offset correction value; and perform negative power processing on the complex value to obtain a frequency offset compensation value.

[0160] In some embodiments, the correction processing module 702 is specifically used to perform a first frequency offset correction processing on the original spread spectrum signal based on the frequency offset compensation value to obtain a corrected signal; perform despreading processing on the corrected signal to obtain a target despread signal; and perform a second frequency offset correction processing on the target despread signal to achieve frequency offset correction processing on the original spread spectrum signal.

[0161] In some embodiments, the correction processing module 702 is further configured to multiply the frequency offset compensation value by the original spread spectrum signal to perform a first frequency offset correction on the original spread spectrum signal to obtain a corrected signal.

[0162] In some embodiments, the correction processing module 702 is specifically used to perform a second frequency offset correction processing on the target demodulated signal through at least one algorithm selected from the group consisting of a frequency locked loop, a phase locked loop, a Fitts algorithm, a left-right algorithm, and an autocorrelation function algorithm, so as to achieve frequency offset correction processing on the original spread spectrum signal.

[0163] In some embodiments, the apparatus further comprises:

[0164] The processing module is used to perform decoding processing and / or demodulation processing on the signal after the second frequency offset correction processing.

[0165] In some embodiments, the correction processing module 702 is further configured to determine a frequency offset estimation result of each of the despread signals by using a Fourier transform processing algorithm.

[0166] In some embodiments, the correction processing module 702 is further configured to perform demodulation processing on each of the demodulated signals based on the demodulation parameters; and perform Fourier transform processing on the demodulated demodulated signals to obtain a frequency offset estimation result.

[0167] In some embodiments, the correction processing module 702 is further configured to multiply each of the despread signals by itself multiple times based on the demodulation parameters to implement demodulation processing.

[0168] In some embodiments, the despreading module 701 is specifically configured to perform multiple different despreading processes on the original spread spectrum signal according to multiple preset spreading factors to obtain multiple despread signals.

[0169] Each module in each of the above devices may be implemented in whole or in part through software, hardware, or a combination thereof. Each of the above modules may be embedded in or independent of the processor in the control device in hardware form, or may be stored in a memory in a computer device in software form, so that the processor can call and execute the corresponding operations of each of the above modules.

[0170] In some embodiments, a computer device is provided, whose internal structure diagram can be as follows: Figure 8 As shown. The computer device includes a processor, a memory, an input / output interface, a communication interface, a display unit and an input device. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface, the display unit and the input device are connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be implemented through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a frequency deviation correction method is implemented.

[0171] Optionally, the computer device further includes a display unit. The display unit of the computer device is used to produce a visually visible image and may be a display screen, a projection device, or a virtual reality imaging device. The display screen may be a liquid crystal display or an electronic ink display screen. The input device of the computer device may be a touch layer covering the display screen, a keypad, a trackball, or a touchpad provided on the computer device housing, or an external keyboard, touchpad, or mouse.

[0172] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the scheme of the present application, and does not constitute a limitation on the control device to which the scheme of the present application is applied. The specific control device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0173] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. For purposes of illustration and not limitation, RAM may be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The processors involved in the various embodiments provided herein may be general-purpose processors, central processing units (CPUs), graphics processors (GPUs), digital signal processors (DSPs), programmable logic devices (PLDs), data processing logic devices based on quantum computing, and the like, without limitation thereto.

[0174] Correspondingly, an embodiment of the present application further provides a computer device, which may be a terminal device or a server.

[0175] like Figure 8 As shown, Figure 8A schematic diagram of the structure of a computer device provided in an embodiment of the present application. The computer device 1000 includes a processor 1001 having one or more processing cores, a memory 1002 having one or more computer-readable storage media, and a computer program stored in the memory 1002 and executable on the processor. The processor 1001 is electrically connected to the memory 1002. Those skilled in the art will appreciate that the computer device structure shown in the figure does not constitute a limitation of the computer device, and may include more or fewer components than shown, or combine certain components, or arrange the components differently.

[0176] The processor 1001 is the control center of the computer device 1000. It connects the various parts of the entire computer device 1000 using various interfaces and lines. By running or loading software programs and / or units stored in the memory 1002 and calling data stored in the memory 1002, it executes various functions of the computer device 1000 and processes data, thereby monitoring the computer device 1000 as a whole. The processor 1001 can be a central processing unit (CPU), a graphics processing unit (GPU), a network processor (NP), etc., and can implement or execute the various methods, steps, and logic blocks disclosed in the embodiments of this application.

[0177] In the embodiment of the present application, the processor 1001 in the computer device 1000 loads instructions corresponding to one or more application processes into the memory 1002 according to the following steps. The processor 1001 then executes the application stored in the memory 1002 to implement various functions, such as: performing multiple different despreading processes on an original spread spectrum signal to obtain multiple despread signals; and performing frequency offset correction on the original spread spectrum signal based on the multiple despread signals. The specific implementation of each of the above operations can be found in the previous embodiment and will not be repeated here.

[0178] Alternatively, as Figure 8 As shown, the computer device 1000 further includes: a touch screen 1003, a radio frequency circuit 1004, an audio circuit 1005, an input unit 1006, and a power supply 1007. Among them, the processor 1001 is electrically connected to the touch screen 1003, the radio frequency circuit 1004, the audio circuit 1005, the input unit 1006, and the power supply 1007 respectively. It can be understood by those skilled in the art that Figure 8 The computer device structure shown in the figure does not constitute a limitation to the computer device, and may include more or fewer components than shown in the figure, or combine certain components, or arrange the components differently.

[0179] The touch display screen 1003 can be used for displaying a graphical user interface and receiving the operation instructions generated by the user acting on the graphical user interface. The touch display screen 1003 can include a display panel and a touch panel. Among them, the display panel can be used for displaying the information input by the user or the information provided to the user and various graphical user interfaces of the computer device, and these graphical user interfaces can be composed of graphics, text, icons, videos and any combination thereof. Optionally, the display panel can be configured in the form of a liquid crystal display (LCD), an organic light emitting diode (OLED), etc. The touch panel can be used for collecting the touch operation of the user thereon or near it (such as the user uses any suitable object or accessory such as a finger, a stylus on the touch panel or near the touch panel), and generates corresponding operation instructions, and the operation instructions execute corresponding programs. Optionally, the touch panel can include two parts: a touch detection device and a touch computer device. Among them, the touch detection device detects the user's touch direction, detects the signal caused by the touch operation, and transmits the signal to the touch computer device; the touch computer device receives the touch information from the touch detection device, converts it into touch point coordinates, and then sends it to the processor 1001, and can receive commands sent by the processor 1001 and execute them. The touch panel can cover the display panel. When the touch panel detects a touch operation on or near it, it is transmitted to the processor 1001 to determine the type of touch event, and then the processor 1001 provides a corresponding visual output on the display panel according to the type of touch event. In an embodiment of the present application, the touch panel and the display panel can be integrated into the touch display screen 1003 to realize input and output functions. However, in some embodiments, the touch panel and the touch panel can be used as two independent components to realize input and output functions. That is, the touch display screen 1003 can also be used as part of the input unit 1006 to realize the input function.

[0180] The RF circuit 1004 may be used to transmit and receive RF signals, thereby establishing wireless communication with a network device or other computer device through wireless communication, and transmitting and receiving signals between the network device or other computer device.

[0181] Audio circuit 1005 can be used to provide an audio interface between the user and the computer device through a speaker and microphone. Audio circuit 1005 can convert received audio data into electrical signals and transmit them to the speaker, which then converts them into sound signals for output. The microphone, on the other hand, converts collected sound signals into electrical signals, which are then received by audio circuit 1005 and converted into audio data. The audio data is then output to processor 1001 for processing, and then transmitted via RF circuit 1004 to, for example, another computer device. Alternatively, the audio data can be output to memory 1002 for further processing. Audio circuit 1005 may also include an earphone jack to allow communication between external headphones and the computer device.

[0182] The input unit 1006 may be configured to receive input digital, character information, or user feature information (such as fingerprint, iris, or facial information), and generate keyboard, mouse, joystick, optical, or trackball signal input related to user settings and function control.

[0183] Power supply 1007 is used to supply power to various components of computer device 1000. Optionally, power supply 1007 can be logically connected to processor 1001 via a power management system, thereby enabling the power management system to manage charging, discharging, and power consumption. Power supply 1007 can also include one or more DC or AC power supplies, a recharging system, a power failure detection circuit, a power converter or inverter, a power status indicator, and other arbitrary components.

[0184] although Figure 8 Not shown in the figure, the computer device 1000 may also include a camera, a sensor, a wireless fidelity module, a Bluetooth module, etc., which will not be described in detail here.

[0185] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0186] Those skilled in the art will appreciate that all or part of the steps in the various methods of the above embodiments may be accomplished by instructions, or by controlling related hardware through instructions. The instructions may be stored in a computer-readable storage medium and loaded and executed by a processor.

[0187] To this end, embodiments of the present application provide a computer-readable storage medium storing multiple computer programs capable of being loaded by a processor to execute any of the frequency offset correction methods provided in embodiments of the present application. The computer program can execute the following steps of the frequency offset correction method: performing multiple different despreading operations on an original spread spectrum signal to obtain multiple despread signals; and performing frequency offset correction on the original spread spectrum signal based on the multiple despread signals. The specific implementation of each of the above operations can be found in the previous embodiments and will not be repeated here.

[0188] The computer-readable storage medium may include a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0189] Since the computer program stored in the computer-readable storage medium can execute any of the frequency offset correction methods provided in the embodiments of the present application, the beneficial effects that can be achieved by any of the frequency offset correction methods provided in the embodiments of the present application can be achieved. Please refer to the previous embodiments for details and will not be repeated here.

[0190] According to one aspect of the present application, a computer program product or computer program is also provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the methods provided in various optional implementations of the above embodiments.

[0191] According to one aspect of this application, Figure 9 As shown, a vehicle 10 is also provided, which includes the above-mentioned computer device and / or frequency offset correction device. The vehicle has all the beneficial effects of the above-mentioned computer device or frequency offset correction device, etc., which will not be described in detail in this application.

[0192] The vehicle can be a fuel vehicle, a plug-in hybrid vehicle or a new energy vehicle, etc., and this application does not make specific limitations on this. In the above-mentioned frequency deviation correction device, computer-readable storage medium, computer equipment, and computer program product embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process and beneficial effects of the above-described frequency deviation correction device, computer-readable storage medium, computer program product, computer equipment and its corresponding units can refer to the description of the frequency deviation correction method in the above embodiment, and will not be repeated here.

[0193] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0194] The above are only preferred embodiments of the present application and do not constitute any form of limitation to the present application. Although the descriptions of each embodiment in the embodiments of the present application have different focuses, for parts that are not described in detail in a certain embodiment, please refer to the relevant embodiments of other embodiments. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application are still within the scope of the technical solution of the present application.

Claims

1. A frequency deviation correction method, characterized in that: The method comprises: Performing multiple different despreading processes on the original spread spectrum signal to obtain multiple despread signals; Based on the multiple despread signals, frequency offset correction processing is performed on the original spread spectrum signal.

2. The method according to claim 1, characterized in that The performing frequency offset correction processing on the original spread spectrum signal based on the multiple despread signals includes: Determining a frequency offset estimation result for each of the despread signals; Based on the frequency offset estimation result of each despread signal, frequency offset correction processing is performed on the original spread spectrum signal.

3. The method according to claim 2, characterized in that The performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset estimation result of each despread signal includes: Determining a frequency offset correction value of the original spread spectrum signal based on a frequency offset estimation result of each of the despread signals; Based on the frequency offset correction value, frequency offset correction processing is performed on the original spread spectrum signal.

4. The method according to claim 3, characterized in that The determining, based on the frequency offset estimation result of each of the despread signals, a frequency offset correction value of the original spread spectrum signal comprises: Determining despreading result indication information of each despread signal based on a frequency offset estimation result of each despread signal; Based on the despreading result indication information, a frequency offset correction value of the original spread spectrum signal is determined.

5. The method according to claim 4, characterized in that The determining, based on the frequency offset estimation result of each of the despread signals, despread result indication information of each of the despread signals comprises: Determining frequency offset statistical characteristic information corresponding to each of the despread signals based on a frequency offset estimation result of each of the despread signals; Despreading result indication information of each despread signal is determined based on the frequency offset statistical characteristic information corresponding to each despread signal.

6. The method according to claim 5, characterized in that The frequency deviation statistical characteristic information includes a signal peak value and / or a signal mean value.

7. The method according to claim 6, characterized in that The determining, based on the frequency offset statistical characteristic information corresponding to each of the despread signals, despread result indication information of each of the despread signals includes: Dividing the signal peak value corresponding to each of the despread signals by the corresponding signal mean value to obtain despreading result indication information of each of the despread signals; Alternatively, the signal mean value corresponding to each of the despread signals is divided by the corresponding signal peak value to obtain despreading result indication information of each of the despread signals.

8. The method according to claim 7, characterized in that The determining, based on the despreading result indication information, a frequency offset correction value of the original spread spectrum signal includes: Determining a target frequency offset estimation result from the frequency offset estimation results of each of the despread signals based on the despread result indication information; Based on the target frequency offset estimation result, a frequency offset correction value of the original spread spectrum signal is determined.

9. The method according to claim 8, characterized in that The determining, based on the despreading result indication information, a target frequency offset estimation result from the frequency offset estimation result of each of the despread signals includes: When the despreading result indication information is obtained by dividing the signal peak value by the signal average value, determining the frequency offset estimation result of the despread signal corresponding to the maximum despreading result indication information as the target frequency offset estimation result, or, In a case where the despreading result indication information is obtained by dividing the signal mean value by the signal peak value, the frequency offset estimation result of the despread signal corresponding to the minimum despreading result indication information is determined as the target frequency offset estimation result.

10. The method according to claim 8, characterized in that The determining, based on the target frequency offset estimation result, a frequency offset correction value of the original spread spectrum signal includes: A frequency offset correction value of the original spread spectrum signal is determined according to the target frequency offset estimation result, the transmission parameters of the despread signal, and the Fourier transform parameters of the despread signal.

11. The method according to claim 10, characterized in that The determining, according to the target frequency offset estimation result, the transmission parameters of the despread signal, and the Fourier transform parameters of the despread signal, of the frequency offset correction value of the original spread spectrum signal comprises: A frequency offset correction value of the original spread spectrum signal is determined according to the target frequency offset estimation result, the transmission parameters of the despread signal, the Fourier transform parameters of the despread signal, and the demodulation parameters of the despread signal.

12. The method according to claim 11, characterized in that The determining, according to the target frequency offset estimation result, the transmission parameters of the despread signal, the Fourier transform parameters of the despread signal, and the demodulation parameters of the despread signal, of the frequency offset correction value of the original spread spectrum signal comprises: determining a first ratio based on a transmission parameter of the despread signal, a Fourier transform parameter of the despread signal, and a demodulation parameter of the despread signal; A frequency offset correction value of the original spread spectrum signal is determined based on the first ratio and the target frequency offset estimation result.

13. The method according to claim 12, characterized in that The determining, based on the first ratio and the target frequency offset estimation result, a frequency offset correction value of the original spread spectrum signal includes: The first ratio is multiplied by a peak value in the target frequency offset estimation result to obtain a frequency offset correction value of the original spread spectrum signal.

14. The method according to claim 3, characterized in that The performing frequency offset correction processing on the original spread spectrum signal based on the frequency offset correction value includes: determining a frequency offset compensation value based on the frequency offset correction value; Based on the frequency offset compensation value, the frequency offset of the original spread spectrum signal is corrected.

15. The method according to claim 14, characterized in that The determining the frequency offset compensation value based on the frequency offset correction value includes: determining a complex value based on the frequency offset correction value; Negative power processing is performed based on the complex value to obtain a frequency offset compensation value.

16. The method according to claim 14, characterized in that The frequency offset correction processing of the original spread spectrum signal based on the frequency offset compensation value includes: Based on the frequency offset compensation value, performing a first frequency offset correction process on the original spread spectrum signal to obtain a corrected signal; performing despreading processing on the corrected signal to obtain a target despread signal; A second frequency offset correction process is performed on the target despread signal to achieve frequency offset correction on the original spread spectrum signal.

17. The method according to claim 16, characterized in that The performing a first frequency offset correction process on the original spread spectrum signal based on the frequency offset compensation value to obtain a corrected signal includes: The frequency offset compensation value is multiplied by the original spread spectrum signal to implement a first frequency offset correction process on the original spread spectrum signal to obtain a corrected signal.

18. The method according to claim 16, characterized in that The performing a second frequency offset correction process on the target despread signal to achieve frequency offset correction process on the original spread spectrum signal includes: The target despread signal is subjected to a second frequency offset correction process by using at least one of a frequency locked loop, a phase locked loop, a Fitts algorithm, a left-right algorithm and an autocorrelation function algorithm, so as to achieve frequency offset correction process for the original spread spectrum signal.

19. The method according to claim 16, wherein The method further comprises: The signal after the second frequency offset correction processing is decoded and / or demodulated.

20. The method according to claim 2, characterized in that Determining a frequency offset estimation result of each of the despread signals includes: The frequency offset estimation result of each despread signal is determined by a Fourier transform processing algorithm.

21. The method according to claim 20, characterized in that Determining a frequency offset estimation result of each of the despread signals by a Fourier transform processing algorithm includes: performing demodulation processing on each of the despread signals based on the demodulation parameters; Perform Fourier transform processing on the despread signal after the demodulation processing to obtain a frequency offset estimation result.

22. The method according to claim 21, characterized in that The step of performing demodulation processing on each of the despread signals based on the demodulation parameters includes: Based on the demodulation parameters, each of the despread signals is multiplied by itself multiple times to achieve demodulation processing.

23. The method according to any one of claims 1 to 22, characterized in that The original spread spectrum signal is subjected to multiple different despreading processes to obtain multiple despread signals, including: According to a plurality of preset spreading factors, the original spread spectrum signal is despread multiple times to obtain a plurality of despread signals.

24. The method according to claim 23, wherein The different preset spreading factors have the same base number but different exponents.

25. A frequency deviation correction device, characterized in that: The device comprises: The despreading module is used to perform multiple despreading processes on the original spread spectrum signal to obtain multiple despread signals; The correction processing module is used to perform frequency offset correction processing on the original spread spectrum signal based on the multiple despread signals.

26. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the frequency offset correction method according to any one of claims 1 to 24 is implemented.

27. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the frequency offset correction method according to any one of claims 1 to 24 is implemented.

28. A computer device, characterized in that: include: a memory having a computer program stored thereon; A processor, configured to execute the computer program in the memory to implement the frequency offset correction method described in any one of claims 1 to 24.

29. A vehicle, characterized in that: Includes the computer device as described in claim 28 and / or the frequency deviation correction device as described in claim 25.

Images