Parameter estimation method, system and device of sine frequency modulation signal and storage medium

Abstract

The invention belongs to the field of signal processing, and particularly relates to a sine frequency modulation signal parameter estimation method, system and device and a storage medium, frequency modulation is carried out on received sine frequency modulation, differential processing is carried out on the sine frequency modulation to obtain instantaneous frequency, then Fourier transform is carried out, the frequency of the sine frequency modulation is preliminarily estimated, accurate estimation frequency is obtained, and the accuracy of the sine frequency modulation is improved. Then, according to the sampling rate, sliding correlation is solved for multiple sets of data in a sampling period, a more accurate estimation frequency corresponding to the maximum value is obtained, the number of sampling points and the sliding amount are continuously adjusted, a more accurate accurate estimation frequency is obtained, and then the data in the period are corrected according to the calculated accurate estimation frequency. And obtaining an instantaneous frequency corresponding to the maximum parameter, and calculating a modulation index and an estimated carrier frequency. The received signal is subjected to frequency modulation by estimating the carrier frequency, the modulation index and the precise estimation frequency, and a more precise signal is obtained.

Description

Technical Field

[0001] The present invention belongs to the field of signal processing, and in particular relates to a parameter estimation method, system, device and storage medium for a sinusoidal frequency modulation signal. Background Art

[0002] Signal forms commonly used in the radar field include linear frequency modulation signals and some nonlinear frequency modulation signals. Among them, nonlinear frequency modulation signals have the important advantage of small mismatch loss. Their detection and parameter estimation have a wide range of applications in the field of radar communication and are a hot topic in the current research of radar communication and sonar signal processing. Sine frequency modulation signals, as a typical nonlinear frequency modulation signal, have the characteristics of low interception distance and high distance resolution, which makes them widely used in radar, communication, sonar and other fields.

[0003] In the related art, the sinusoidal frequency modulation signal parameter estimation algorithm mainly adopts the redistribution smoothed pseudo Wigne-Ville distribution (RSPWVD) method and Hough transform to estimate the sinusoidal frequency modulation signal parameters.

[0004] Regarding the above-mentioned related technologies, the redistributed smoothed pseudo Wigne-Ville distribution (RSPWVD) method and Hough transform method for estimating the parameters of sinusoidal frequency modulated signals have high computational complexity and the cross terms cannot accurately estimate the signal parameters. At the same time, since the instantaneous frequency is used for calculation, it cannot work properly under low signal-to-noise ratio. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a parameter estimation method, system, device and storage medium for a sinusoidal frequency modulated signal, so as to reduce the inaccuracy of received signal parameters caused by noise and environmental factors and improve the accuracy.

[0006] A method for estimating parameters of a sinusoidal frequency modulated signal, comprising:

[0007] Obtaining the received sinusoidal frequency modulation signal;

[0008] Differentiating the sinusoidal frequency modulation signal to obtain a differential signal, and obtaining an instantaneous frequency according to the differential signal;

[0009] Performing Fourier transform on the instantaneous frequency to obtain an estimated frequency of the sinusoidal frequency modulation signal;

[0010] The estimated frequency is adjusted according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency;

[0011] Performing frequency offset compensation on the time domain signal of the sinusoidal frequency modulation signal according to the accurate estimated frequency to obtain a modulation index;

[0012] An estimated carrier frequency is calculated based on the instantaneous frequency and the compensation frequency during frequency offset compensation, and the estimated carrier frequency, the precise estimated frequency and the modulation index are used as estimated parameters.

[0013] Optionally, differentiating the sinusoidal signal to obtain a differential signal, and obtaining the instantaneous frequency according to the differential signal includes:

[0014] Differentiating the sinusoidal frequency modulation signal to obtain a differential signal;

[0015] The differential signal is:

[0016]

[0017] Obtaining an instantaneous frequency according to the differential signal;

[0018] The instantaneous frequency is:

[0019] Among them, s(t)s*(t-1) is the difference, A is the signal amplitude of the sinusoidal FM signal, j is the imaginary unit in the complex domain, s(t) and s(t-1) are the sinusoidal FM signals received at two different times, and f m is the frequency of the sinusoidal signal in the sinusoidal frequency modulated signal to be estimated, m f is the modulation index to be estimated, f 0 is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, m f '=m f f m .

[0020] Optionally, adjusting the estimated frequency according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency includes:

[0021] Get the sampling rate of the sinusoidal FM signal;

[0022] Calculating the number of first sampling points in a sinusoidal period according to the sampling rate and the estimated frequency;

[0023] Obtaining the number of frequency modulation cycles M according to the total length of the number of sampling points in a single sampling, the first number of sampling points, and the estimation accuracy, wherein the single sampling includes sampling of multiple sinusoidal cycles;

[0024] Obtaining a first sliding value according to the first number of sampling points and the estimation accuracy;

[0025] According to the first sliding value, the number of frequency modulation cycles M and the sliding correlation expression, a sliding correlation value of M-1 signal cycles when the first sliding value is slid left and right around the first sampling point number as the center is obtained;

[0026] The sliding related expression is:

[0027]

[0028] Among them, D and f m The estimation accuracy of N ce is the number of sampling points in one cycle, τ is the sliding amount, s(n+τ) is the time domain signal, To round down, n represents the discrete sampling point subscript, and M is the number of integer cycles of the sinusoidal frequency modulation signal;

[0029] Calculate the position of the maximum value of the sliding correlation expression to obtain a first estimated frequency and an estimated number of second sampling points within a period;

[0030] Reduce the sliding range to obtain sliding related values;

[0031] Obtaining an accurately estimated third number of sampling points according to the second number of sampling points, the reduced sliding range, and a sliding-related expression;

[0032] An accurate estimated frequency is obtained according to the third number of sampling points and the sampling rate.

[0033] Optionally, performing fractional frequency offset compensation on a time domain signal of the sinusoidal signal according to the precise estimated frequency to obtain a modulation index includes:

[0034] According to the accurate estimated frequency, obtaining an accurate estimated period;

[0035] When there is no frequency offset, the sampled signal value within an accurate estimation period exists:

[0036] s(n)=s(n+iN c ),0≤n<N c ;

[0037] Where s(n) is the signal value at the nth sampling point; i represents the i-th cycle, N c is the number of sampling points;

[0038] Adding signals in multiple cycles to obtain an added signal;

[0039]

[0040] According to the added signal, the instantaneous frequency is obtained, and the instantaneous frequency is integrated and accumulated within one cycle to obtain the modulation index;

[0041] When there is a frequency deviation:

[0042] Obtain correction formula;

[0043] According to the correction formula, a set of correction data is obtained;

[0044] Obtaining a preset gradient, and obtaining a replenishment amount according to the preset gradient;

[0045] Adding a set of the correction data within the estimation period to obtain a set of accumulated data, with a total of a supplementary number of sets of accumulated data;

[0046] The modulation index is calculated based on the accumulated data of the supplementary quantity group.

[0047] Optionally, calculating the modulation index according to the accumulated data of the supplementary quantity group includes:

[0048] Calculating instantaneous frequencies for the accumulated data of the supplementary quantity groups respectively, and obtaining a number of instantaneous frequencies;

[0049] According to the instantaneous frequency and parameter calculation formulas, several parameter values ​​are obtained;

[0050] Get the instantaneous frequency corresponding to the maximum parameter value;

[0051] The modulation index is calculated according to the instantaneous frequency corresponding to the maximum parameter value.

[0052] Optionally, calculating the estimated carrier frequency according to the instantaneous frequency and the supplementary frequency during frequency offset compensation includes:

[0053] According to the instantaneous frequency corresponding to the maximum parameter value, a corresponding instantaneous phase sequence and parameter group are obtained;

[0054] Calculating a first carrier frequency according to the instantaneous frequency of the sinusoidal frequency modulation signal;

[0055] According to the parameter group and the accurate estimated frequency, a supplementary frequency is obtained;

[0056] The compensation frequency is added to the first carrier frequency to obtain the estimated carrier frequency.

[0057] Optionally, calculating the first carrier frequency according to the instantaneous frequency of the sinusoidal frequency modulation signal includes:

[0058] The instantaneous frequency of the sinusoidal frequency modulation signal is expressed as:

[0059]

[0060] In one cycle,

[0061] Where A is the amplitude, f 0 is the first carrier frequency, T is the period, f 0is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, is the instantaneous frequency, m f is the modulation index to be estimated, f m is the frequency of the sinusoidal signal in the sinusoidal FM signal to be estimated.

[0062] A parameter estimation system for a sinusoidal frequency modulated signal, comprising:

[0063] An acquisition module, used for acquiring a received sinusoidal signal;

[0064] A first calculation module, configured to obtain a differential signal by differentiating the sinusoidal signal, and obtain an instantaneous frequency according to the differential signal;

[0065] A transformation module, used for performing Fourier transformation on the instantaneous frequency to obtain an estimated frequency of the sinusoidal signal;

[0066] An adjustment module, used to adjust the estimated frequency according to the estimated frequency and the sampling rate to obtain an accurate estimated frequency;

[0067] A compensation module, configured to perform frequency deviation compensation on a time domain signal of the sinusoidal signal according to the precise estimated frequency to obtain a modulation index;

[0068] The estimation module is used to calculate the estimated carrier frequency according to the instantaneous frequency and the compensation frequency during frequency offset compensation, and use the estimated carrier frequency, the precise estimated frequency and the modulation index as estimation parameters.

[0069] A terminal device comprises a memory and a processor. The memory stores a computer program that can be run on the processor. When the processor loads and executes the computer program, a parameter estimation method of a sinusoidal frequency modulation signal is adopted.

[0070] A computer-readable storage medium stores a computer program. When the computer program is loaded and executed by a processor, a parameter estimation method of a sinusoidal frequency modulation signal is adopted.

[0071] The beneficial effects of the present invention are:

[0072] The received sinusoidal FM signal is modulated by performing differential processing on the sinusoidal FM signal to obtain the instantaneous frequency, and then Fourier transform is performed to preliminarily estimate the frequency of the sinusoidal FM to obtain an accurate estimated frequency. Then, according to the sampling rate, sliding correlation is calculated for multiple sets of data within a sampling period to obtain a more accurate estimated frequency corresponding to the maximum value. Finally, the correlation length of the periodic signal is adjusted to obtain an accurate estimated frequency. Then, according to the calculated accurate estimated frequency, the data within the period is corrected to obtain the instantaneous frequency corresponding to the maximum parameter, and then the modulation index and estimated carrier frequency are calculated. The received signal is modulated by estimating the carrier frequency, modulation index and accurate estimated frequency to obtain a more accurate signal. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] Figure 1 The figure is a flow chart of a parameter estimation method of a sinusoidal frequency modulation signal according to the present invention. DETAILED DESCRIPTION

[0074] A parameter estimation method for a sinusoidal frequency modulated signal, such as Figure 1 As shown, the present invention includes:

[0075] S100: Acquire a received sinusoidal frequency modulation signal.

[0076] Specifically, the sinusoidal signal received by the radar system or jammer system may be affected by noise, interference or signal attenuation, resulting in inaccurate received signals. Therefore, the received sinusoidal frequency modulation needs to be FM-modulated. The received sinusoidal signal frequency modulation is expressed as:

[0077]

[0078] Among them, f 0 is the carrier frequency to be estimated, m f is the modulation index to be estimated, f m is the frequency of the sinusoidal signal in the sinusoidal FM signal to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal FM signal, j is the imaginary unit in the complex domain, A is the signal amplitude of the sinusoidal FM signal, and S(t) is the received sinusoidal FM signal.

[0079] S110, differentiating the sinusoidal frequency modulation signal to obtain a differential signal, and obtaining an instantaneous frequency according to the differential signal.

[0080] Differentiating the sinusoidal frequency modulated signal to obtain a differential signal, and obtaining the instantaneous frequency based on the differential signal includes:

[0081] Differentiate the sinusoidal frequency modulated signal to obtain a differential signal;

[0082] The differential signal is:

[0083]

[0084] Among them, s(t)s*(t-1) is the difference of the sinusoidal frequency modulated signal.

[0085] Obtain instantaneous frequency based on the differential signal;

[0086] The instantaneous frequency is:

[0087]

[0088] Among them, s(t)s*(t-1) is the difference, A is the signal amplitude of the sinusoidal FM signal, j is the imaginary unit in the complex domain, s(t) and s(t-1) are the sinusoidal FM signals received at two different times, and f m is the frequency of the sinusoidal signal in the sinusoidal frequency modulated signal to be estimated, m f is the modulation index to be estimated, f 0 is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, m f '=m f f m .

[0089] S120, performing Fourier transform on the instantaneous frequency to obtain an estimated frequency of the sinusoidal frequency modulation signal.

[0090] Specifically, the instantaneous frequency is downsampled, and the downsampled instantaneous frequency is subjected to Fourier transformation, the amplitude spectrum is calculated, and the position idx corresponding to the maximum amplitude in the spectrum is found. max , according to which the corresponding sinusoidal signal spectrum is calculated, the calculation formula is as follows:

[0091]

[0092] Among them, FFTLen is the Fourier transform length, |FFTLen / 2-idx max | is the position of the maximum value in the amplitude spectrum, K is the sampling multiple, F s is the sampling rate, f me is the estimated frequency of the sinusoidal signal. The estimated frequency of the sinusoidal signal is not accurate enough and needs further processing.

[0093] S130: Adjust the estimated frequency according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency.

[0094] The estimated frequency is adjusted according to the estimated frequency and sampling rate to obtain the accurate estimated frequency including:

[0095] Get the sampling rate of the sinusoidal frequency modulated signal.

[0096] Specifically, the sampling rate refers to the number of times a signal is sampled per unit time during digital signal processing or digitization.

[0097] Through the sampling rate, we can get the number of sampling points in a sine cycle, specifically:

[0098] N c =F s / f m .

[0099] The number of first sampling points in a sinusoidal period and the estimated value of the period are calculated according to the sampling rate and the estimated frequency.

[0100] Specifically, the first sampling point number is calculated by estimating the frequency, and the period estimation value is calculated by using the inverse of the estimated frequency.

[0101] The number of frequency modulation cycles M is obtained according to the total length of the number of sampling points in a single sampling, the first number of sampling points and the estimation accuracy, wherein the single sampling includes sampling of multiple sinusoidal cycles.

[0102] Specifically, the number of frequency modulation cycles M is the number of integer frequency modulation cycles existing in the total data length, specifically:

[0103]

[0104] Among them, N is the total length of the sampling points, N ce is the first sampling point number, which is estimated by f m Calculated, To round down.

[0105] A first sliding value is obtained according to the first number of sampling points and the estimation accuracy.

[0106] Specifically, the first sliding value is the maximum absolute value of the range selected when calculating the correlation value, and the first sliding value is calculated as follows:

[0107] The sliding range is:

[0108] According to the first sliding value, the frequency modulation cycle number M and the sliding correlation expression, the sliding correlation value of M-1 signal cycles when the first sliding value is slid left and right around the first sampling point number is obtained.

[0109] Specifically, since the estimated f m With the actual f m There is an error. In order to obtain a more accurate f m The estimated value of is obtained by using signals of multiple frequency modulation cycles to obtain the sliding correlation.

[0110] The sliding related expression is:

[0111]

[0112] Among them, D and f m The estimation accuracy of m The normalized estimation error is less than 5%, then the value of D can be 1 / 0.05=20, N ce is the first sampling point number, s(n+τ) is the time domain signal, To round down, n represents the subscript of the discrete sampling point, M is the number of integer cycles of the sinusoidal FM signal, and τ is the sliding amount.

[0113] The position of the maximum value of the sliding correlation expression is calculated to obtain the first estimated frequency and the estimated number of second sampling points within one cycle.

[0114] Specifically, by finding the position where the maximum value of the sliding correlation value r(τ) modulus is located, a more accurate f can be obtained. m The estimated value, denoted by f m1 And the estimated value N of the number of sampling points in one cycle ce1 (second sampling point number).

[0115] The first estimated frequency is f m1 , N ce1 To estimate the number of sampling points in a cycle more accurately, the first estimated frequency f m1 Compared to f m Closer to the actual value.

[0116] Reduce the sliding range to obtain sliding related values.

[0117] Specifically, since f m1 The estimation accuracy is already very high, so the sliding amount can be further reduced. In this embodiment, its range is -10≤τ≤10, that is, only the estimated value N ce1 Observe 10 sampling points on the left and right.

[0118] According to the second number of sampling points, the reduced sliding range and the sliding-related expression, an accurately estimated third number of sampling points is obtained.

[0119] Specifically, the position where the maximum value of the modulus of the sliding correlation value r(τ) is located is continued to be obtained to obtain the third sampling point number.

[0120] An accurate estimated frequency is obtained according to the third number of sampling points and the sampling rate.

[0121] Specifically, me2 =F s / Nce2 .

[0122] Among them, f me2 To accurately estimate the frequency, N ce2 is the third sampling point number.

[0123] S140. Perform fractional frequency offset compensation on a time domain signal of the sinusoidal frequency modulation signal according to the precise estimated frequency to obtain a modulation index.

[0124] According to the accurate estimated frequency and the time domain signal of the sinusoidal signal, the frequency deviation compensation is performed on the accurate estimated frequency of multiple cycles, and the modulation index is obtained including:

[0125] After finding the accurate estimated frequency, the differential signal of the sinusoidal signal is obtained, and the following formula is obtained:

[0126]

[0127] From the properties of the sine function, we know that

[0128]

[0129] Then there is

[0130]

[0131] Where Bw is the signal bandwidth, m f is the modulation index.

[0132] According to the accurate estimation frequency, an accurate estimation period is obtained.

[0133] Specifically, since the sinusoidal signal frequency f is estimated m2 So the cycle

[0134] However, when the signal-to-noise ratio is low, the error of the instantaneous phase obtained is large, and phase flipping may occur, thereby increasing the estimation error.

[0135] When there is no frequency offset, the sampled signal value within an accurate estimation period exists:

[0136] s(n)=s(n+iN c ),0≤n<N c .

[0137] Where s(n) is the signal value at the nth sampling point; i represents the i-th cycle, N c is the number of sampling points.

[0138] The signals in multiple cycles are added to obtain an added signal.

[0139]

[0140] Specifically, 1 (n) is the added signal.

[0141] According to the added signal, the instantaneous frequency is obtained, and the instantaneous frequency is integrated and accumulated within one cycle to obtain the modulation index;

[0142] When there is a frequency deviation:

[0143] Get the correction formula.

[0144] Specifically, the correction formula is:

[0145]

[0146] where s k is the kth group of data after fractional frequency offset correction, F s is the signal sampling rate, n is the subscript of the corresponding signal, f k is the spectrum compensation value of the kth group of signals,

[0147] According to the correction formula, a set of correction data is obtained.

[0148] Specifically, it is divided into multiple groups of data according to the gradient, and is divided into 20 groups of data in this embodiment.

[0149] A preset gradient is obtained, and a replenishment quantity is obtained according to the preset gradient.

[0150] A set of correction data is added up within the estimation period to obtain a set of accumulated data, and there are a total of supplementary number sets of accumulated data.

[0151] The modulation index is calculated based on the accumulated data of the supplementary quantity groups.

[0152] Specifically, when there is a frequency offset, the above accumulation will have reverse accumulation, so it is necessary to normalize the fractional multiple spectrum in the signal s(n). Through simulation analysis, it can be seen that when the normalized fractional frequency offset is less than 5%, it has little effect on the accumulation performance. Therefore, it can be used in the range of 0 to the estimated f me2 Within the range, the signal is corrected for decimal frequency offset according to the gradient. me2 / 20 is the gradient for frequency offset compensation calculation.

[0153] The modulation index calculated based on the accumulated data of the supplementary quantity group includes:

[0154] Specifically, the 20 groups of time domain signals are periodically accumulated in the time domain to obtain 20 groups of accumulated data. The accumulated data are then used to obtain the instantaneous frequency And calculate y according to the following formula k value:

[0155]

[0156] Where t is time, and its discretization expression is

[0157]

[0158] According to the required y k The modulation index and signal bandwidth can be obtained, where f m Using the estimated value f me2 Substitute into the calculation.

[0159] S150, calculating an estimated carrier frequency according to the instantaneous frequency and the supplementary frequency during frequency offset compensation, and taking the estimated carrier frequency, the precise estimated frequency and the modulation index as estimated parameters.

[0160] According to the instantaneous frequency and the supplementary frequency during frequency offset compensation, the estimated carrier frequency is calculated as follows:

[0161] According to the instantaneous frequency corresponding to the maximum parameter value, the corresponding instantaneous phase sequence and parameter group are obtained;

[0162] Calculating a first carrier frequency according to the instantaneous frequency of the sinusoidal frequency modulation signal;

[0163] Based on the parameter groups and the accurate estimated frequencies, the supplementary frequencies are obtained;

[0164] The compensation frequency is added to the first carrier frequency to obtain an estimated carrier frequency.

[0165] Specifically, the instantaneous frequency of the sinusoidal FM signal is:

[0166]

[0167] In a period T,

[0168]

[0169] So we can get the carrier frequency f 01 Estimated value of

[0170]

[0171] Where A is the amplitude, f 0 is the first carrier frequency, T is the period, f 0 is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, is the instantaneous frequency (instantaneous phase sequence), m f is the modulation index to be estimated, f m is the frequency of the sinusoidal signal in the sinusoidal FM signal to be estimated.

[0172] The accuracy of instantaneous frequency calculation can be improved by removing the decimal frequency deviation from the original data of multiple cycles and then accumulating them, thereby improving the accuracy of carrier frequency estimation. max , take the corresponding instantaneous phase sequence

[0173] According to k max It can be seen that the compensation frequency is The estimated signal carrier frequency can be obtained Among them, f 01 is the carrier frequency calculated through multiple cycles, f 0 is the final estimated carrier frequency.

[0174] Through the above processing, the modulation index in the FM signal, the frequency of the sinusoidal signal and the carrier frequency are estimated to obtain a more accurate signal, which plays an important role in the fields of radar, communication and sonar, such as ranging, calculating target distance and speed, etc.

[0175] A parameter estimation system for sinusoidal frequency modulation, comprising:

[0176] An acquisition module, used for acquiring a received sinusoidal signal;

[0177] A first calculation module, configured to obtain a differential signal by differentiating the sinusoidal signal, and obtain an instantaneous frequency according to the differential signal;

[0178] A transformation module, used for performing Fourier transformation on the instantaneous frequency to obtain an estimated frequency of the sinusoidal signal;

[0179] An adjustment module, used to adjust the estimated frequency according to the estimated frequency and the sampling rate to obtain an accurate estimated frequency;

[0180] A compensation module, used for performing fractional frequency offset compensation on a time domain signal of the sinusoidal signal according to the precise estimated frequency to obtain a modulation index;

[0181] The estimation module is used to calculate the estimated carrier frequency according to the instantaneous frequency and the compensation frequency during frequency offset compensation, and use the estimated carrier frequency, the precise estimated frequency and the modulation index as estimation parameters.

[0182] The embodiment of the present application also discloses a terminal device, including a memory and a processor. The memory stores a computer program that can be run on the processor. When the processor loads and executes the computer program, a parameter estimation method of a sinusoidal frequency modulation signal is adopted.

[0183] The terminal device may be a computer device such as a desktop computer, a laptop computer or a cloud server, and the terminal device includes but is not limited to a processor and a memory. For example, the terminal device may also include input and output devices, a network access device and a bus.

[0184] Among them, the processor can adopt a central processing unit (CPU). Of course, according to actual usage, other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. can also be adopted. The general-purpose processor can adopt a microprocessor or any conventional processor, etc., and this application does not impose any restrictions on this.

[0185] Among them, the memory can be an internal storage unit of the terminal device, such as a hard disk or memory of the terminal device, or it can be an external storage device of the terminal device, such as a plug-in hard disk, a smart memory card (SMC), a secure digital card (SD) or a flash memory card (FC) equipped on the terminal device, etc., and the memory can also be a combination of an internal storage unit and an external storage device of the terminal device. The memory is used to store computer programs and other programs and data required by the terminal device. The memory can also be used to temporarily store data that has been output or is to be output, and this application does not impose any restrictions on this.

[0186] Among them, through this terminal device, a parameter estimation method of a sinusoidal frequency modulation signal in the above embodiment is stored in the memory of the terminal device, and is loaded and executed on the processor of the terminal device for easy use.

[0187] The embodiment of the present application further discloses a computer-readable storage medium, and the computer-readable storage medium stores a computer program, wherein when the computer program is executed by a processor, a parameter estimation method for a sinusoidal frequency modulation signal in the above embodiment is adopted.

[0188] Among them, the computer program can be stored in a computer-readable medium, the computer program includes computer program code, the computer program code can be in the form of source code, object code, executable file or certain middleware, etc. The computer-readable medium includes any entity or device that can carry the computer program code, recording medium, USB flash drive, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium, etc. It should be noted that the computer-readable medium includes but is not limited to the above-mentioned components.

[0189] Among them, through the computer-readable storage medium, a parameter estimation method of a sinusoidal frequency modulation signal in the above embodiment is stored in a computer-readable storage medium, and is loaded and executed on a processor to facilitate the storage and application of the above method.

[0190] A person skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of protection of the present application is limited to these examples. In line with the concept of the present application, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present application as above, which are not provided in detail for the sake of simplicity.

[0191] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of one or more embodiments of the present application should be included in the protection scope of the present application.

Claims

1. A method for estimating parameters of a sinusoidal frequency modulated signal, characterized in that: include: Obtaining the received sinusoidal frequency modulation signal; Differentiating the sinusoidal frequency modulation signal to obtain a differential signal, and obtaining an instantaneous frequency according to the differential signal; Performing Fourier transform on the instantaneous frequency to obtain an estimated frequency of the sinusoidal frequency modulation signal; The estimated frequency is adjusted according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency; Performing frequency offset compensation on the time domain signal of the sinusoidal frequency modulation signal according to the accurate estimated frequency to obtain a modulation index; An estimated carrier frequency is calculated based on the instantaneous frequency and the compensation frequency during frequency offset compensation, and the estimated carrier frequency, the precise estimated frequency and the modulation index are used as estimated parameters.

2. The method for estimating parameters of a sinusoidal frequency modulated signal as claimed in claim 1, wherein: The step of differentiating the sinusoidal frequency modulation signal to obtain a differential signal, and obtaining the instantaneous frequency according to the differential signal comprises: Differentiating the sinusoidal frequency modulation signal to obtain a differential signal; The differential signal is: Obtaining an instantaneous frequency according to the differential signal; The instantaneous frequency is: Among them, s(t)s*(t-1) is the difference, A is the signal amplitude of the sinusoidal FM signal, j is the imaginary unit in the complex domain, s(t) and s(t-1) are the sinusoidal FM signals received at two different times, and f m is the frequency of the sinusoidal signal in the sinusoidal frequency modulated signal to be estimated, m f is the modulation index to be estimated, f0 is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, m f '=m f f m .

3. The method for estimating parameters of a sinusoidal frequency modulated signal as claimed in claim 1, wherein: The step of adjusting the estimated frequency according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency includes: Get the sampling rate of the sinusoidal FM signal; Calculating the number of first sampling points in a sinusoidal period according to the sampling rate and the estimated frequency; Obtaining the number of frequency modulation cycles M according to the total length of the number of sampling points in a single sampling, the number of first sampling points, and the estimation accuracy, wherein the single sampling includes sampling of multiple sinusoidal cycles; Obtaining a first sliding value according to the first number of sampling points and the estimation accuracy; According to the first sliding value, the number of frequency modulation cycles M and the sliding correlation expression, a sliding correlation value of M-1 signal cycles when the first sliding value is slid left and right around the first sampling point number as the center is obtained; The sliding related expression is: Among them, D and f m The estimation accuracy of N ce is the number of sampling points in a sinusoidal cycle, τ is the sliding amount, s(n+τ) is the time domain signal, To round down, n represents the discrete sampling point subscript, and M is the number of integer cycles of the sinusoidal frequency modulation signal; Calculate the position of the maximum value of the sliding correlation expression to obtain a first estimated frequency and an estimated number of second sampling points within a period; Reduce the sliding range to obtain sliding related values; Obtaining an accurately estimated third number of sampling points according to the second number of sampling points, the reduced sliding range, and a sliding-related expression; An accurate estimated frequency is obtained according to the third number of sampling points and the sampling rate.

4. The method for estimating parameters of a sinusoidal frequency modulated signal as claimed in claim 1, wherein: The step of performing fractional frequency offset compensation on the time domain signal of the sinusoidal signal according to the precise estimated frequency to obtain a modulation index comprises: According to the accurate estimated frequency, obtaining an accurate estimated period; When there is no frequency offset, the sampled signal value within an accurate estimation period exists: s(n)=s(n+iN c ),0≤n<N c ; Where s(n) is the signal value at the nth sampling point; i represents the i-th cycle, N c is the number of sampling points; Adding signals in multiple cycles to obtain an added signal; According to the added signal, the instantaneous frequency is obtained, and the instantaneous frequency is integrated and accumulated within one cycle to obtain the modulation index; When there is a frequency deviation: Obtain correction formula; According to the correction formula, a set of correction data is obtained; Obtaining a preset gradient, and obtaining a replenishment amount according to the preset gradient; Adding a set of the correction data within the estimation period to obtain a set of accumulated data, with a total of a supplementary number of sets of accumulated data; The modulation index is calculated based on the accumulated data of the supplementary quantity group.

5. The method for estimating parameters of a sinusoidal frequency modulation signal as claimed in claim 4, characterized in that: The calculating the modulation index according to the accumulated data of the supplementary quantity group comprises: Calculating instantaneous frequencies for the accumulated data of the supplementary quantity groups respectively, and obtaining a number of instantaneous frequencies; According to the instantaneous frequency and parameter calculation formulas, several parameter values ​​are obtained; Get the instantaneous frequency corresponding to the maximum parameter value; The modulation index is calculated according to the instantaneous frequency corresponding to the maximum parameter value.

6. The method for estimating parameters of a sinusoidal frequency modulated signal as claimed in claim 5, wherein: The calculating the estimated carrier frequency according to the instantaneous frequency and the supplementary frequency during frequency offset compensation includes: According to the instantaneous frequency corresponding to the maximum parameter value, a corresponding instantaneous phase sequence and parameter group are obtained; Calculating a first carrier frequency according to the instantaneous frequency of the sinusoidal frequency modulation signal; According to the parameter group and the accurate estimated frequency, a supplementary frequency is obtained; The compensation frequency is added to the first carrier frequency to obtain the estimated carrier frequency.

7. The method for estimating parameters of a sinusoidal frequency modulation signal as claimed in claim 6, wherein: The step of calculating the first carrier frequency according to the instantaneous frequency of the sinusoidal frequency modulation signal comprises: The instantaneous frequency of the sinusoidal frequency modulation signal is expressed as: In one cycle, Where A is the amplitude, f0 is the first carrier frequency, T is the period, f0 is the carrier frequency to be estimated, θ is the initial phase of the sinusoidal signal in the sinusoidal frequency modulated signal, is the instantaneous frequency, m f is the modulation index to be estimated, f m is the frequency of the sinusoidal signal in the sinusoidal FM signal to be estimated.

8. A parameter estimation system for a sinusoidal frequency modulated signal, characterized in that: include: An acquisition module, used for acquiring a received sinusoidal frequency modulation signal; A first calculation module, configured to obtain a differential signal by differentiating the sinusoidal frequency modulation signal, and obtain an instantaneous frequency according to the differential signal; A transformation module, used for performing Fourier transformation on the instantaneous frequency to obtain an estimated frequency of the sinusoidal frequency modulation signal; An adjustment module, used for adjusting the estimated frequency according to the sampling rate of the sinusoidal frequency modulation signal to obtain an accurate estimated frequency; A compensation module, configured to perform fractional frequency offset compensation on a time domain signal of the sinusoidal frequency modulation signal according to the precise estimated frequency to obtain a modulation index; The estimation module is used to calculate the estimated carrier frequency according to the instantaneous frequency and the compensation frequency during frequency offset compensation, and use the estimated carrier frequency, the precise estimated frequency and the modulation index as estimation parameters.

9. A terminal device, comprising a memory and a processor, characterized in that: The memory stores a computer program that can be run on the processor, and when the processor loads and executes the computer program, the method according to any one of claims 1 to 7 is adopted.

10. A computer-readable storage medium having a computer program stored therein, characterized in that: When the computer program is loaded and executed by a processor, the method according to any one of claims 1 to 7 is adopted.

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