2fsk signal denoising and reconstruction method, device and equipment and storage medium

Abstract

The application relates to a 2FSK signal denoising and reconstruction method, device, equipment and storage medium. The method combines prior information with necessary information obtained by using an intermediate frequency estimation method and a frequency offset estimation method, and fits a 2FSK signal of an interference-free receiving end by means of signal modulation. The method fits the 2FSK signal of the receiving end from the perspective of modulation, avoids problems possibly caused by obtaining a fitted signal by processing the signal of the receiving end, and to some extent, retains the characteristics of a transmission system in signal transmission by using prior information of a transmitting device, a channel feature and a receiving device to make a feature model and correcting the feature model by using a received signal.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of signal processing, in particular to a 2FSK signal denoising and reconstruction method, device, equipment and storage medium. BACKGROUND

[0002] In the process of non-cooperative electromagnetic environment monitoring, 2FSK signals may encounter various interferences in the transmission process and thus cause signal distortion. The existing methods for removing interference from the receiving end mainly include filter filtering and algorithm interference removal. Filter filtering mainly filters out out-of-band noise by passing the received 2FSK signal through a specific filter, but due to the non-ideal characteristics of the filter, the output signal may also produce a certain degree of distortion while the residual part of the out-of-band noise is removed. When other algorithms including fitting algorithms are used to process interference, it may misjudge or miss the noise points. SUMMARY

[0003] Therefore, it is necessary to provide a 2FSK signal denoising and reconstruction method, device, equipment and storage medium to overcome the above technical problems. The method can overcome the shortcomings of the existing methods for removing interference from the received 2FSK signal using filtering and other means to fit the interference-free signal, which may easily introduce new interference and interference removal is not ideal.

[0004] A 2FSK signal denoising and reconstruction method, the method comprising:

[0005] Obtaining a 2FSK signal to be processed.

[0006] Performing intermediate frequency estimation on the 2FSK signal to be processed to extract the signal intermediate frequency.

[0007] Performing parameter extraction after digital down-conversion processing of the signal intermediate frequency to obtain the extracted parameters of the 2FSK signal to be fitted.

[0008] Performing frequency offset estimation according to the extracted parameters of the 2FSK signal to be fitted and the parameters extracted from the prior information to obtain a frequency offset parameter.

[0009] According to the frequency offset parameter, the signal intermediate frequency and the prior information, a fitting waveform of the 2FSK signal to be processed is generated in the form of 2FSK signal modulation.

[0010] In one embodiment, the intermediate frequency estimation of the 2FSK signal to be processed includes:

[0011] Performing DFT on the 2FSK signal to be processed to obtain a power spectrum.

[0012] Optimizing the power spectrum through mathematical processing, and then obtaining the signal intermediate frequency by averaging the two highest spectral peaks.

[0013] In one embodiment, the frequency offset parameter is obtained according to the parameters extracted from the 2FSK signal to be fitted and the parameters extracted from the prior information, including:

[0014] The first characteristic model is determined according to the parameters extracted from the prior information.

[0015] The first characteristic model is corrected to obtain the second characteristic model according to the parameters extracted from the 2FSK signal to be fitted by using a predetermined algorithm; wherein the frequency offset parameter is a parameter of the second characteristic model.

[0016] In one embodiment, the prior information includes: symbol rate, sampling rate and symbol information.

[0017] The fitting waveform of the 2FSK signal to be processed is generated according to the frequency offset parameter, the signal intermediate frequency and the prior information by using the 2FSK signal modulation mode, including:

[0018] The 2FSK fitting signal to be processed with certain initial phase difference, time delay and amplitude scaling is generated according to the prior information and the frequency offset parameter.

[0019] In the modulation process, the symbol information is up-sampled to obtain an up-sampled signal corresponding to the symbol rate and the sampling rate, the up-sampled signal is shaped filtered by a filter to obtain a digital baseband signal, and then the digital baseband signal is added with the frequency of f to obtain a frequency addition result, and the frequency addition result is digitally up-converted to obtain the fitting interference-free received 2FSK signal; wherein f para is the frequency offset parameter, f IF is the signal intermediate frequency, and f s is the sampling rate.

[0020] A 2FSK signal denoising and reconstruction device, the device comprising:

[0021] A signal acquisition module is configured to acquire a 2FSK signal to be processed.

[0022] An intermediate frequency estimation module is configured to perform intermediate frequency estimation on the 2FSK signal to be processed to extract a signal intermediate frequency.

[0023] A frequency offset parameter estimation module is configured to perform parameter extraction on the signal intermediate frequency after digital down-conversion processing to obtain parameters extracted from the 2FSK signal to be fitted; and to perform frequency offset estimation according to the parameters extracted from the 2FSK signal to be fitted and the parameters extracted from the prior information to obtain a frequency offset parameter.

[0024] A waveform fitting and modulation module is configured to generate a fitting waveform of the 2FSK signal to be processed according to the frequency offset parameter, the signal intermediate frequency and the prior information by using the 2FSK signal modulation mode.

[0025] In one of the embodiments, the intermediate frequency estimation module is further configured to perform DFT on the to-be-processed 2FSK signal to obtain a power spectrum; perform mathematical processing on the power spectrum to optimize the power spectrum, and then obtain the intermediate frequency of the signal by averaging two highest spectrum peaks.

[0026] In one of the embodiments, the frequency offset parameter estimation module is further configured to determine a first characteristic model according to parameters extracted from prior information; correct the first characteristic model according to parameters extracted from the to-be-fitted 2FSK signal by using a predetermined algorithm to obtain a second characteristic model; and the frequency offset parameter is a parameter of the second characteristic model.

[0027] In one of the embodiments, the prior information includes symbol rate, sampling rate and symbol information; and the waveform fitting and modulation module is further configured to generate the to-be-processed 2FSK fitting signal with certain initial phase difference, time delay and amplitude scaling according to the prior information and the frequency offset parameter; in the modulation process, the symbol information is up-sampled to obtain an up-sampled signal corresponding to the symbol rate and the sampling rate, the up-sampled signal is filtered by a filter to obtain a digital baseband signal, and then the digital baseband signal is added with a frequency of f , and the frequency addition result is digitally up-converted to obtain the fitting interference-free received 2FSK signal; wherein, f para (n) is the frequency offset parameter, f IF is the signal intermediate frequency, and f s is the sampling rate.

[0028] A computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0029] Obtain a to-be-processed 2FSK signal.

[0030] Perform intermediate frequency estimation on the to-be-processed 2FSK signal to extract the signal intermediate frequency.

[0031] Perform parameter extraction after digital down-conversion processing of the signal intermediate frequency to obtain parameters extracted from the to-be-fitted 2FSK signal.

[0032] Perform frequency offset estimation according to the parameters extracted from the to-be-fitted 2FSK signal and parameters extracted from prior information to obtain a frequency offset parameter.

[0033] Generate a fitting waveform of the to-be-processed 2FSK signal by using a 2FSK signal modulation mode according to the frequency offset parameter, the signal intermediate frequency and the prior information.

[0034] A computer readable storage medium stores a computer program, and the computer program is executed by a processor to implement the following steps:

[0035] Obtaining a 2FSK signal to be processed.

[0036] Performing intermediate frequency estimation on the 2FSK signal to be processed to extract the intermediate frequency of the signal.

[0037] After performing digital down-conversion processing on the intermediate frequency of the signal, parameters are extracted to obtain the extracted parameters of the 2FSK signal to be fitted.

[0038] According to the extracted parameters of the 2FSK signal to be fitted and the parameters extracted from the prior information, frequency offset estimation is performed to obtain a frequency offset parameter.

[0039] According to the frequency offset parameter, the intermediate frequency of the signal, and the prior information, a 2FSK signal modulation method is used to generate a fitting waveform of the 2FSK signal to be processed.

[0040] The 2FSK signal noise reduction and reconstruction method, device, equipment and storage medium described above, by combining prior information with necessary information obtained by using intermediate frequency estimation method and frequency offset estimation method, fitting the 2FSK signal of the interference-free receiving end by signal modulation method. This method starts from the modulation point of view to fit the receiving end 2FSK signal, which avoids the problems that may be caused by the existing method of obtaining a fitted signal by processing the receiving end signal; using the prior information of the transmitting device, the channel characteristics and the receiving device to make a characteristic model and correcting it with the received signal to some extent preserves the characteristics of the transmission system in the signal transmission. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 The flowchart of the 2FSK signal noise reduction and reconstruction method in one embodiment;

[0042] Figure 2 The flowchart of the 2FSK signal noise reduction and reconstruction method in another embodiment;

[0043] Figure 3 The intermediate frequency power spectrum of the 2FSK signal in another embodiment;

[0044] Figure 4 The first-order characteristic model and the fitting result of the first-order characteristic model in another embodiment;

[0045] Figure 5 The results obtained by running on multiple platforms in another embodiment, where (a) is the real part curve of the 2FSK signal to be processed and the simulation signal (0 intermediate frequency), (b) is the imaginary part curve of the 2FSK signal to be processed and the simulation signal (0 intermediate frequency), (c) is the real part curve of the 2FSK signal to be processed and the simulation signal, and (d) is the imaginary part curve of the 2FSK signal to be processed and the simulation signal;

[0046] Figure 6A structural block diagram of a 2FSK signal denoising and reconstruction device in one embodiment;

[0047] Figure 7 An internal structural diagram of a computer device in one embodiment. DETAILED DESCRIPTION

[0048] In order to make the purposes, technical solutions and advantages of the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not to limit the present application.

[0049] In one embodiment, as shown in Figure 2 , a 2FSK signal denoising and reconstruction method is provided, which comprises the following steps:

[0050] Step 100: obtaining a 2FSK signal to be processed.

[0051] Step 102: performing intermediate frequency estimation on the 2FSK signal to be processed to extract the intermediate frequency of the signal.

[0052] Step 104: performing parameter extraction after digital down-conversion processing on the intermediate frequency of the signal to obtain the extracted parameters in the 2FSK signal to be fitted.

[0053] Step 106: performing frequency offset estimation according to the extracted parameters in the 2FSK signal to be fitted and the parameters extracted from the prior information to obtain the frequency offset parameter.

[0054] Step 108: generating a fitted waveform of the 2FSK signal to be processed in a 2FSK signal modulation manner according to the frequency offset parameter, the intermediate frequency of the signal and the prior information.

[0055] In the above-mentioned 2FSK signal denoising and reconstruction method, the method combines the prior information with the necessary information obtained by the intermediate frequency estimation method and the frequency offset estimation method, and fits the 2FSK signal at the receiving end by signal modulation. This method fits the 2FSK signal at the receiving end from the perspective of modulation, avoiding the problems that may be caused by obtaining the fitted signal by processing the receiving signal; using the prior information of the transmitting device, the channel characteristics and the receiving device to make a characteristic model and correcting it with the receiving signal to some extent preserves the characteristics of the transmission system in the signal transmission.

[0056] In one embodiment, step 102 comprises: performing DFT on the 2FSK signal to be processed to obtain a power spectrum; performing mathematical processing on the power spectrum to optimize the power spectrum, and then obtaining the intermediate frequency of the signal by averaging the two highest spectral peaks. The intermediate frequency power spectrum is shown in Figure 3 .

[0057] Specifically, the 2FSK signal is a signal in which the frequency of a sinusoidal carrier is discretely changed with a binary digital baseband signal, and after frequency down-conversion and sampling, the intermediate frequency I / Q sequence obtained at the receiving end is the receiving end 2FSK signal to be processed, and the expression is wherein k represents the serial number of k symbol information, T is the symbol duration, represents the phase constant of each symbol, a k represents the polarity of each symbol, and takes the value of 1 or -1, g(n) is a shaping pulse, f s is the sampling rate, f IF is the intermediate frequency of the signal to be solved. The frequency interval of the 2FSK signal is 40 kHz, so there are two spectral peaks in its power spectrum. The method first performs DFT on the signal to obtain the power spectrum, then optimizes the power spectrum through mathematical processing, and finally obtains the signal intermediate frequency by averaging the two highest spectral peaks.

[0058] In one embodiment, step 106 includes: determining a first feature model according to parameters extracted from prior information; and correcting the first feature model according to parameters extracted from the 2FSK signal to be fitted to obtain a second feature model; wherein the frequency offset parameter is a parameter of the second feature model.

[0059] Specifically, the frequency offset caused by noise in the transmission process of the 2FSK signal is the frequency offset to be removed, and the frequency offset caused by the comprehensive action of the transmitting device, the channel characteristics, and the receiving device is the frequency offset to be extracted. The frequency offset parameter extraction includes two aspects: extracting parameters from prior-known device information and channel information, and extracting parameters from the 2FSK signal to be fitted at the receiving end. The first feature model is made using the parameters extracted from the prior information, and the second model is obtained by correcting the first model using a specific algorithm using the parameters extracted from the 2FSK signal to be fitted. The obtained second model parameter is the frequency offset parameter.

[0060] The first feature model and the first feature model fitting are as shown in Figure 4 .

[0061] In one embodiment, the prior information includes: symbol rate, sampling rate, and symbol information; and step 108 includes: generating a 2FSK fitting signal to be processed with certain initial phase difference, time delay, and amplitude scaling according to the prior information and the frequency offset parameter; in the modulation process, the symbol information is up-sampled to obtain an up-sampled signal corresponding to the symbol rate and the sampling rate, the up-sampled signal is shaped filtered by a filter to obtain a digital baseband signal, and then the frequency of the digital baseband signal is added to , and the frequency addition result is digitally up-converted to obtain a fitting interference-free received 2FSK signal; wherein f para (n) is the frequency offset parameter, f IFis the intermediate frequency of the signal, f s is the sampling rate.

[0062] Specifically, the fitting signal is modulated. With the priori information of symbol rate, sampling rate and symbol, and in combination with the obtained frequency offset parameter, the received 2FSK signal with certain initial phase difference, time delay and amplitude scaling can be obtained. In the modulation process, the symbol information is first obtained by signal upsampling to obtain an upsampled signal corresponding to the symbol rate and the sampling rate. Then, the upsampled signal is shaped filtered by a filter to obtain a digital baseband signal. Finally, the digital baseband signal is added with a signal with a frequency of f , and the 2FSK modulation is completed at the same time of digital up-conversion (wherein f para (n) is the frequency offset parameter), and finally the fitting interference-free received 2FSK signal is obtained. The fitting signal is also an I / Q sequence.

[0063] It should be understood that, although Figure 1 the steps in the flowchart of the fitting signal are displayed in sequence according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise explicitly stated herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other orders. Moreover, Figure 1 at least part of the steps in the fitting signal can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least part of other steps or sub-steps or stages of other steps.

[0064] In one verification embodiment, the received 2FSK signal to be processed is input, and the intermediate frequency estimation, the frequency offset parameter extraction, and finally the fitting signal modulation are sequentially performed to obtain the fitting interference-free received 2FSK signal. This method can be written in various programming languages and run on various platforms to obtain results as shown in Figure 5 , wherein (a) is the real part curve of the 2FSk signal to be processed and the simulation signal (0 intermediate frequency), (b) is the imaginary part curve of the 2FSk signal to be processed and the simulation signal (0 intermediate frequency), (c) is the real part curve of the 2FSk signal to be processed and the simulation signal, and (d) is the real part curve of the 2FSk signal to be processed and the simulation signal. As can be seen from the simulation results, compared with the original signal, the reconstructed signal has more regular and clear local features, and has a higher degree of agreement with the ideal noiseless 2FSK signal waveform.

[0065] In one embodiment, as shown in Figure 6 , a 2FSK signal noise reduction and reconstruction device is provided, comprising a signal acquisition module, an intermediate frequency estimation module, a frequency offset parameter estimation module, and a waveform fitting and modulation module,

[0066] wherein:

[0067] a signal acquisition module, configured to acquire a 2FSK signal to be processed.

[0068] a center frequency estimation module, configured to perform center frequency estimation on the 2FSK signal to be processed, and extract a center frequency of the signal.

[0069] a frequency offset parameter estimation module, configured to perform parameter extraction on the center frequency of the signal after digital down-conversion processing, to obtain parameters extracted from the 2FSK signal to be fitted; and perform frequency offset estimation according to the parameters extracted from the 2FSK signal to be fitted and parameters extracted from prior information, to obtain a frequency offset parameter.

[0070] a waveform fitting and modulation module, configured to generate a fitted waveform of the 2FSK signal to be processed in a 2FSK signal modulation manner according to the frequency offset parameter, the center frequency of the signal, and the prior information.

[0071] In one of the embodiments, the center frequency estimation module is further configured to perform DFT on the 2FSK signal to be processed to obtain a power spectrum; perform mathematical processing on the power spectrum to optimize the power spectrum, and then obtain the center frequency of the signal by averaging two highest spectral peaks.

[0072] In one of the embodiments, the frequency offset parameter estimation module is further configured to determine a first characteristic model according to the parameters extracted from the prior information; and correct the first characteristic model according to the parameters extracted from the 2FSK signal to be fitted by using a predetermined algorithm, to obtain a second characteristic model; wherein the frequency offset parameter is a parameter of the second characteristic model.

[0073] In one of the embodiments, the prior information includes a symbol rate, a sampling rate, and symbol information; and the waveform fitting and modulation module is further configured to generate the 2FSK signal to be processed with certain initial phase difference, time delay, and amplitude scaling according to the prior information and the frequency offset parameter; and in the modulation process, perform signal up-sampling on the symbol information to obtain an up-sampled signal corresponding to the symbol rate and the sampling rate, perform filter shaping filtering on the up-sampled signal to obtain a digital baseband signal, and then add a frequency of the digital baseband signal to a frequency of the 2FSK signal to be processed, to obtain a frequency addition result, and perform digital up-conversion on the frequency addition result to obtain a fitted 2FSK signal without interference. wherein f para (n) is the frequency offset parameter, f IF is the center frequency of the signal, and f s is the sampling rate.

[0074] The specific limitations of the 2FSK signal denoising and reconstruction device can be referred to the limitations of the 2FSK signal denoising and reconstruction method, which will not be repeated here. Each module in the 2FSK signal denoising and reconstruction device can be realized by software, hardware and their combination. The above-mentioned modules can be embedded in or independent of the processor in the computer device in hardware form, or can be stored in the memory in the computer device in software form, so that the processor calls and executes the operations corresponding to each module.

[0075] In one embodiment, a computer device, which can be a terminal, is provided, and an internal structure diagram of the computer device can be as shown in Figure 7 The computer device includes a processor, a memory, a network interface, a display screen and an input device connected by a system bus. The processor of the computer device is configured 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 operating system and the computer program in the non-volatile storage medium to run. The network interface of the computer device is configured to communicate with external terminals through network connection. The computer program is executed by the processor to implement a 2FSK signal denoising and reconstruction method. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen. The input device of the computer device can be a touch layer overlaid on the display screen, or a key, trackball or touchpad arranged on the shell of the computer device, or an external keyboard, touchpad or mouse, etc.

[0076] Those skilled in the art can understand that Figure 7 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the computer device to which the scheme of the present application is applied. The specific computer device can include more or fewer components than those shown in the figure, or combine certain components, or have a different component arrangement.

[0077] In one embodiment, a computer device is provided, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0078] In one embodiment, a computer readable storage medium is provided, which stores a computer program. The computer program is executed by a processor to implement the steps in the above method embodiments.

[0079] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a non-volatile computer readable storage medium, and when the computer program is executed, the processes of the above-mentioned embodiments of the methods can be included. Any reference to memory, storage, databases, or other media in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0080] The technical features of the above embodiments can be combined in any way. In order to make the description simple, not all possible combinations of the technical features in the above embodiments are described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present application.

[0081] The above embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are all within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the appended claims.

Claims

1. A method for 2FSK signal denoising and reconstruction, characterized in that, The method comprises: acquiring a 2FSK signal to be processed; performing intermediate frequency estimation on the 2FSK signal to be processed to extract a signal intermediate frequency; performing parameter extraction after digital down-conversion processing of the signal intermediate frequency to obtain extracted parameters in the 2FSK signal to be fitted; performing frequency offset estimation according to the extracted parameters in the 2FSK signal to be fitted and parameters extracted from prior information to obtain a frequency offset parameter; wherein the prior information comprises a symbol rate, a sampling rate and symbol information; According to the frequency offset parameter, the signal intermediate frequency, and prior information, a 2FSK signal modulation mode is used to generate a fitting waveform of a to-be-processed 2FSK signal; specifically comprising: according to the prior information and the frequency offset parameter, a to-be-processed 2FSK fitting signal with certain initial phase difference, time delay, and amplitude scaling is generated; in the modulation process, symbol information is up-sampled to obtain an up-sampled signal corresponding to a symbol rate and a sampling rate, the up-sampled signal is filtered by a filter shaping filter to obtain a digital baseband signal, and then the digital baseband signal is added with a frequency of , and the frequency addition result is digitally up-converted to obtain a fitting interference-free received 2FSK signal; wherein, is a frequency offset parameter, is a signal intermediate frequency, is a sampling rate.

2. The 2FSK signal denoising and reconstruction method according to claim 1, characterized in that, the intermediate frequency estimation on the 2FSK signal to be processed to extract a signal intermediate frequency comprises: performing DFT on the 2FSK signal to be processed to obtain a power spectrum; performing mathematical processing on the power spectrum to optimize the power spectrum, and then obtaining the signal intermediate frequency by averaging the two highest spectral peaks.

3. The 2FSK signal denoising and reconstruction method according to claim 1, characterized in that, the frequency offset estimation according to the extracted parameters in the 2FSK signal to be fitted and parameters extracted from prior information to obtain a frequency offset parameter comprises: determining a first characteristic model according to the parameters extracted from the prior information; correcting the first characteristic model according to the parameters extracted from the 2FSK signal to be fitted by using a predetermined algorithm to obtain a second characteristic model; wherein the frequency offset parameter is a parameter of the second characteristic model.

4. A 2FSK signal denoising and reconstruction apparatus, characterized in that, The device comprises: a signal acquisition module for acquiring a 2FSK signal to be processed; an intermediate frequency estimation module for performing intermediate frequency estimation on the 2FSK signal to be processed to extract a signal intermediate frequency; a frequency offset parameter estimation module for performing parameter extraction after digital down-conversion processing of the signal intermediate frequency to obtain extracted parameters in the 2FSK signal to be fitted; and performing frequency offset estimation according to the extracted parameters in the 2FSK signal to be fitted and parameters extracted from prior information to obtain a frequency offset parameter; a waveform fitting and modulation module for generating a fitted waveform of the 2FSK signal to be processed in a 2FSK signal modulation manner according to the frequency offset parameter, the signal intermediate frequency and prior information; The prior information includes: symbol rate, sampling rate and symbol information; the waveform fitting and modulation module is further configured to generate a to-be-processed 2FSK fitting signal with certain initial phase difference, time delay and amplitude scaling according to the prior information and the frequency offset parameter; in the modulation process, the symbol information is up-sampled to obtain an up-sampled signal corresponding to the symbol rate and the sampling rate, the up-sampled signal is filtered by a filter to obtain a digital baseband signal, and then the digital baseband signal is added with a frequency of , and the frequency addition result is digitally up-converted to obtain a fitting interference-free received 2FSK signal; wherein, is a frequency offset parameter, is a signal intermediate frequency, is a sampling rate.

5. The apparatus of claim 4, wherein, the intermediate frequency estimation module is further configured to perform DFT on the 2FSK signal to be processed to obtain a power spectrum; and perform mathematical processing on the power spectrum to optimize the power spectrum, and then obtain the signal intermediate frequency by averaging the two highest spectral peaks.

6. The apparatus of claim 4, wherein, the frequency offset parameter estimation module is further configured to determine a first characteristic model according to the parameters extracted from the prior information; correct the first characteristic model according to the parameters extracted from the 2FSK signal to be fitted by using a predetermined algorithm to obtain a second characteristic model; wherein the frequency offset parameter is a parameter of the second characteristic model. 7.A computer device, comprising a memory and a processor, wherein the memory stores a computer program, and the computer device is configured to perform the method according to any one of claims 1-6 when the computer program is executed by the processor. The processor executes the computer program to implement the 2FSK signal noise reduction and reconstruction method in any one of claims 1 to 3.

8. A computer-readable storage medium having stored thereon a computer program, characterized in that, The computer program is executed by the processor to implement the 2FSK signal noise reduction and reconstruction method in any one of claims 1 to 3.

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