A high-dynamic weak frequency hopping signal carrier frequency measurement system

Abstract

The application discloses a high-dynamic weak frequency hopping signal carrier frequency measurement system, and belongs to the wireless communication field.The system comprises a sampling buffer module, a double-block grouping module, a frequency hopping pattern module, a frequency unjumping module, a frequency deviation slotting module, a compensation correction module, a CIC decimation module, a zero-padding FFT module, an integral accumulation module and a detection and calculation module.The double-block grouping module groups the sampling data in double blocks.The frequency unjumping module unjumps the frequency of the data grouped in double blocks.The compensation correction module compensates and corrects the data after frequency unjumping.The zero-padding FFT module performs Fourier transform on the data after CIC decimation.The detection and calculation module obtains integral peak value information by processing all the integral accumulation data, and calculates the carrier Doppler frequency shift of the received signal by combining a quadratic function interpolation correction method.The application can quickly, effectively and accurately measure the carrier frequency of the frequency hopping signal, and provides a high-precision carrier Doppler frequency shift measurement value for subsequent signal processing.

Description

Technical Field

[0001] This invention relates to the field of wireless communication, and more specifically, to a high-dynamic weak frequency-hopping signal carrier frequency measurement system. Background Technology

[0002] Frequency hopping (FH) communication systems use a frequency hopping sequence to modulate baseband information at the transmitting end, and then use the same frequency hopping sequence to de-hop at the receiving end to recover the original baseband information. During transmission, the bandwidth occupied by the signal is much larger than the bandwidth required to transmit information. It can ensure reliable and stable communication in complex and harsh electromagnetic environments and has advantages such as anti-fading, anti-interference, and low interception. It has been continuously developed and widely used in aerospace telemetry and control, electronic countermeasures, radar detection, mobile communication and other fields.

[0003] In frequency-hopping communication systems, the detection carrier is often in a high-speed maneuvering state, with radial relative high-speed motion between the transmitting and receiving ends. The carrier frequency of the received signal changes drastically over time, resulting in a significant carrier Doppler shift. The received frequency-hopping signal is in a high-dynamic scenario, requiring the measurement system to have a wider frequency measurement range and better frequency measurement accuracy. Secondly, the transmission distance between the transmitting and receiving ends is very long, and considering complex factors such as obstruction, electromagnetic interference, and multipath effects, the received power of the frequency-hopping signal will be severely attenuated by various channel losses, generally being completely submerged in various strong noises and interferences. The measurement system must meet the low signal-to-noise ratio (SNR) requirement. Therefore, in complex scenarios with large frequency dynamics and low SNR, frequency-hopping communication systems face greater challenges. How to effectively, accurately, and quickly achieve the measurement synchronization of the frequency-hopping signal carrier frequency has become a key technical problem for frequency-hopping communication systems.

[0004] Currently, commonly used frequency measurement methods can be summarized into three main categories: First, methods based on modern spectrum estimation, which have the disadvantages of high complexity, large computational load, and long computation time; second, methods based on phase difference, which only utilize phase information and do not consider frequency domain information, and are only suitable for measuring single-frequency signals, requiring a high signal-to-noise ratio; and third, spectral line refinement methods based on interpolation fitting FFT transform, which have the disadvantages of frequency measurement accuracy being highly dependent on the approximation degree of the fitting function, complex equation solving calculations, being greatly affected by noise, and serious frequency mismeasurement phenomena in low signal-to-noise ratio scenarios.

[0005] Traditional measurement systems only perform coarse measurements of the carrier frequency, without considering the Doppler transitions added to the carrier caused by the different frequency points of adjacent frequency hopping. Furthermore, they only perform frequency measurements within a single frequency hopping interval, which cannot meet the detection requirements of weak frequency hopping signals. Therefore, traditional measurement systems cannot adapt to complex scenarios such as large frequency dynamics and low signal-to-noise ratios, nor can they meet the measurement performance requirements of actual frequency hopping communication systems. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a high dynamic weak frequency hopping signal carrier frequency measurement system. This system can overcome Doppler shift, has high frequency measurement accuracy, and good real-time processing performance. It can quickly, effectively, and accurately measure the carrier frequency of frequency hopping signals in complex scenarios such as high frequency dynamics and low signal-to-noise ratio, providing high-precision carrier Doppler frequency shift measurements for subsequent signal processing.

[0007] The objective of this invention is achieved through the following solution:

[0008] A high-dynamic weak frequency-hopping signal carrier frequency measurement system includes:

[0009] The module includes a sampling buffer module, a dual-block grouping module, a frequency hopping pattern module, a frequency de-hopping module, a frequency offset slotting module, a compensation and correction module, a CIC downsampling module, a zero-padding FFT module, an integral accumulation module, and a detection and calculation module.

[0010] The sampling buffer module samples and buffers the received signal, controlling the read and write logic of the sampled data; the dual-block grouping module groups the sampled data output by the sampling buffer module into dual blocks; the frequency de-hopping module performs frequency de-hopping on the data after dual-block grouping according to the frequency hopping frequency point output by the frequency hopping pattern module; the frequency offset slotting module divides the carrier Doppler frequency shift into multiple frequency sub-slots according to the carrier Doppler frequency shift range; the compensation correction module compensates and corrects the data after frequency de-hopping according to the frequency hopping frequency point and the carrier Doppler frequency shift output by the frequency offset slotting module; the CIC downsampling module performs CIC downsampling processing on the compensated and corrected data; the zero-padding FFT module performs Fourier transform on the data after CIC downsampling using a zero-padding method; the integration accumulation module integrates and accumulates the Fourier transform data using an incoherent integration method to obtain integrated accumulated data; the detection and calculation module obtains the integrated peak information by using a comparison search method on all integrated accumulated data, and calculates the carrier Doppler frequency shift of the received signal according to the frequency hopping frequency point at the current time using a quadratic function interpolation correction method.

[0011] Furthermore, the sampling data buffer parameter of the sampling buffer module is N×(M+1), where N is the total number of received signal sampling data in each frequency hopping time, satisfying N=f s / R fh f s R is the sampling rate of the received signal. fh Where M is the frequency hopping rate, and M is the number of integral accumulation points.

[0012] Furthermore, the dual-block grouping module divides the N consecutive sampled data output by the sampling buffer module into one data block, and divides the N×(M+1) sampled data into data block 0, data block 1, ..., data block M-1, data block M. Using the dual-block grouping method, two consecutive data blocks are combined into one new data block, which is converted into 2N×M sampled data.

[0013] Furthermore, the frequency de-hopping module determines the frequency hopping frequency f output by the frequency hopping pattern module. hopp (m), where m is the integral accumulation exponent, satisfying m∈(0,1,…,M-1), and is calculated using the formula CW. h o pp =-f h o pp (m)×2 32 / f s Data conversion is performed to obtain the frequency hopping control word CW. hopp For frequency control word CW hopp The query address is obtained by accumulating the data, and the frequency hopping frequency f is generated through address mapping and table lookup. hopp (m) local carrier, frequency hopping frequency f hopp The local carrier (m) is multiplied by the m-th block of 2N sampled data output by the dual-block grouping module to perform frequency dehopping on the data after dual-block grouping.

[0014] Furthermore, the frequency offset slotting module is based on the carrier Doppler frequency shift range. The carrier Doppler frequency shift is divided into D+1 frequency sub-slots, where, This represents the minimum carrier Doppler frequency shift. The maximum value of the carrier Doppler frequency shift, and the carrier Doppler frequency shift search step. for Then the carrier Doppler frequency shift of the d-th frequency sub-slot for Where d is the frequency sub-slot search round, satisfying d∈(0,1,…,D).

[0015] Furthermore, the compensation correction module adjusts the frequency based on the frequency hopping frequency f. hopp (m) and the carrier Doppler frequency shift output by the frequency offset slotting module Using calculation formula Perform data transformation, where f RF Given the radio frequency, the carrier Doppler frequency shift frequency control word is obtained. Frequency control word The query address is obtained by accumulating the data, and the carrier Doppler frequency shift is generated through address mapping and table lookup. Local carrier, carrier Doppler frequency shift The local carrier and frequency de-hopping module outputs the m-th block of 2N sampled data, and performs complex multiplication operation to compensate and correct the carrier Doppler frequency shift of the frequency de-hopping data.

[0016] Furthermore, the CIC downsampling module adjusts the downsampling frequency f. B The calculation formula CW is used. B =f B / f s ×2 32 Data conversion is performed by generating a clearing pulse using a direct digital frequency synthesizer (DDS). An accumulator is used to continuously accumulate the compensated and corrected data. When the clearing pulse is valid, the accumulated value is output, and the data input to the accumulator is integrated and cleared. This process is repeated to complete the CIC downsampling processing of the m-th block of 2N sampled data output by the compensation and correction module.

[0017] Furthermore, the zero-padding FFT module pads the downsampled data output by the CIC downsampled module with zeros to K, and performs a K-point fast Fourier transform on the K zero-padding data to obtain K fast Fourier transform data.

[0018] Furthermore, the integration accumulation module employs an incoherent integration method to perform M integration accumulations on K×M Fast Fourier Transform data to obtain K integrated and accumulated data.

[0019] Furthermore, the detection and calculation module uses a comparison search method to obtain the sub-slot cycle d where the maximum peak value is located by integrating and accumulating the data of all frequency sub-slots. vpp The index position k where the maximum peak value is located vpp Maximum peak integral accumulation data y vpp The two integral accumulation data points adjacent to the maximum peak value are y and y, respectively. - y + The exponential position k of the maximum peak value after correction is obtained by using a quadratic function interpolation correction method. max for Combined with the current frequency hopping frequency f hopp Calculate the carrier Doppler frequency shift f of the received signal. dopl for

[0020] The beneficial effects of this invention include:

[0021] (1) Adaptable to high dynamic scenarios. In this invention, the dual-block grouping module eliminates the related cumulative energy loss caused by the uncertainty of the initial phase of the frequency hopping carrier, and the frequency offset slotting module divides the carrier Doppler frequency shift into multiple frequency sub-slots according to the carrier Doppler frequency shift range. Compared with traditional measurement methods, it has a very large carrier frequency measurement range and can adapt to the measurement needs of high dynamic scenarios.

[0022] (2) Overcoming Doppler jump. In this invention, the compensation and correction module compensates and corrects the data after frequency de-hopping based on the carrier Doppler frequency shift output by the frequency hopping frequency point and the frequency offset slot module. Compared with the traditional measurement method, this overcomes the Doppler jump added to the carrier caused by the difference between adjacent frequency hopping points.

[0023] (3) High frequency measurement accuracy. In this invention, the zero-padding FFT module uses the data zero-padding method to perform a fast Fourier transform with a large number of points, and the detection and calculation module uses a comparison search combined with a quadratic function interpolation correction method to calculate the carrier Doppler frequency shift of the received signal based on the frequency hopping point at the current time. Compared with traditional measurement methods, it can provide high-precision carrier Doppler frequency shift measurement values.

[0024] (4) Good real-time performance. In this invention, a high-frequency clock is used to quickly process the sampled data output by the sampling buffer module, which reduces the amount of related calculations. Multiple data processing branches are used for parallel search, which greatly shortens the data processing time. Compared with traditional measurement systems, the acquisition speed is significantly improved, and it has good real-time performance. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram illustrating the structural principle of the high dynamic weak frequency hopping signal carrier frequency measurement system according to an embodiment of the present invention.

[0027] Figure 2 for Figure 1 A schematic diagram of the structural principle of the dual-block grouping module in the diagram;

[0028] Figure 3 for Figure 1 A schematic diagram of the structural principle of the frequency de-hopping module in the middle;

[0029] Figure 4 for Figure 1 A schematic diagram of the structural principle of the compensation and correction module in the diagram;

[0030] Figure 5 for Figure 1 A schematic diagram of the structural principle of the CIC downsampling module. Detailed Implementation

[0031] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.

[0032] like Figure 1 As shown, according to the present invention, a high-dynamic weak frequency-hopping signal carrier frequency measurement system includes: a sampling buffer module, a dual-block grouping module, a frequency hopping pattern module, a frequency de-hopping module, a frequency offset slotting module, a compensation and correction module, a CIC downsampling module, a zero-padding FFT module, an integration and accumulation module, and a detection and calculation module; the sampling buffer module samples and buffers the received signal and controls the read and write logic of the sampled data; the dual-block grouping module performs dual-block grouping on the sampled data output by the sampling buffer module; the frequency de-hopping module performs frequency de-hopping on the data after dual-block grouping according to the frequency hopping frequency point output by the frequency hopping pattern module; the frequency offset slotting module divides the carrier Doppler frequency shift into multiple frequency ranges according to the carrier Doppler frequency shift range. The frequency hopping slot and frequency offset slot module compensate and correct the carrier Doppler frequency shift output by the frequency hopping slot and frequency offset slot module. The CIC downsampling module performs CIC downsampling on the compensated and corrected data. The zero-padding FFT module performs a large-point fast Fourier transform on the CIC downsampling data by zero-padding. The integration and accumulation module integrates and accumulates the fast Fourier transform data by non-coherent integration to obtain integrated and accumulated data. The detection and calculation module obtains the integrated peak information by comparing and searching all integrated and accumulated data, and calculates the carrier Doppler frequency shift of the received signal based on the current frequency hopping slot by combining the quadratic function interpolation correction method.

[0033] In an optional implementation, the sampling buffer module samples and buffers the received signal, controlling the read and write logic of the sampled data. The sampled data buffer parameter is N×(M+1), where N is the total number of received signal sampled data in each frequency hopping time, satisfying N=f s / R fh f s R is the sampling rate of the received signal. fh Where M is the frequency hopping rate, and M is the number of integral accumulation points.

[0034] Optional implementation schemes, such as Figure 2 As shown, the dual-block grouping module divides the N consecutive sampled data output by the sampling buffer module into one data block, and divides the N×(M+1) sampled data into data block 0, data block 1, ..., data block M-1, data block M. Using the dual-block grouping method, two consecutive data blocks are combined into one new data block, which is converted into 2N×M sampled data.

[0035] Optional implementation schemes, such as Figure 3As shown, the frequency de-hopping module determines the frequency hopping frequency point f output by the frequency hopping pattern module. hopp (m), where m is the integral accumulation exponent, satisfying m∈(0,1,…,M-1), and is calculated using the formula CW. hopp =-f hopp (m)×2 32 / f s Data conversion is performed to obtain the frequency hopping control word CW. hopp For frequency control word CW hopp The query address is obtained by accumulating the data, and the frequency hopping frequency f is generated through address mapping and table lookup. hopp (m) local carrier, frequency hopping point f hopp The local carrier (m) is multiplied by the m-th block of 2N sampled data output by the dual-block grouping module to perform frequency dehopping on the data after dual-block grouping.

[0036] In an optional implementation, the frequency offset slotting module is based on the carrier Doppler frequency shift range. The carrier Doppler frequency shift is divided into D+1 frequency sub-slots, where, This represents the minimum carrier Doppler frequency shift. The maximum value of the carrier Doppler frequency shift, and the carrier Doppler frequency shift search step. for Then the carrier Doppler frequency shift of the d-th frequency sub-slot for Where d is the frequency sub-slot search round, satisfying d∈(0,1,…,D).

[0037] Optional implementation schemes, such as Figure 4 As shown, the compensation and correction module adjusts according to the frequency hopping point f. hopp (m) and the carrier Doppler frequency shift output by the frequency offset slotting module Using calculation formula Perform data transformation, where f RF Given the radio frequency, the carrier Doppler frequency shift frequency control word is obtained. Frequency control word The query address is obtained by accumulating the data, and the carrier Doppler frequency shift is generated through address mapping and table lookup. Local carrier, carrier Doppler frequency shift The local carrier and frequency de-hopping module outputs the m-th block of 2N sampled data, and performs complex multiplication operation to compensate and correct the carrier Doppler frequency shift of the frequency de-hopping data.

[0038] Optional implementation schemes, such as Figure 5 As shown, the CIC downsampling module adjusts the downsampling frequency f. B The calculation formula CW is used. B =fB / f s ×2 32 Data conversion is performed by generating a clearing pulse using a direct digital frequency synthesizer (DDS). An accumulator is used to continuously accumulate the compensated and corrected data. When the clearing pulse is valid, the accumulated value is output, and the data input to the accumulator is integrated and cleared. This process is repeated to complete the CIC downsampling processing of the m-th block of 2N sampled data output by the compensation and correction module.

[0039] In an optional implementation, the zero-padding FFT module pads the downsampled data output by the CIC downsampled module with zeros to K, and performs a K-point Fast Fourier Transform on the K zero-padding data to obtain K Fast Fourier Transform data; the integration and accumulation module uses an incoherent integration method to perform M integrations and accumulations on the K×M Fast Fourier Transform data to obtain K integrated and accumulated data.

[0040] In an optional implementation, the detection and calculation module uses a comparison search method to obtain the sub-slot cycle d where the maximum peak value is located by integrating and accumulating the data of all frequency sub-slots. vpp The index position k where the maximum peak value is located vpp Maximum peak integral accumulation data y vpp The two integral accumulation data points adjacent to the maximum peak value are y and y, respectively. - y + The exponential position k of the maximum peak value after correction is obtained by using a quadratic function interpolation correction method. max for Combined with the current frequency hopping point f hopp Calculate the carrier Doppler frequency shift f of the received signal. dopl for

[0041] The following are further examples:

[0042] Taking a frequency-hopping signal transmitted by a satellite as an example, the operating frequency f RF The frequency is 22.0 GHz, and the received signal sampling rate is f. s The frequency hopping rate is 180.0MHz, and the frequency hopping rate R is... fh 20 kHop / s, frequency hopping interval The frequency hopping bandwidth is 40kHz, the frequency hopping bandwidth is [-81.92MHz, +81.92MHz], and the carrier Doppler frequency shift range is... [-900.0kHz, +900.0kHz].

[0043] The sampling buffer module samples and buffers the received signal, controlling the read and write logic of the sampled data. The sampled data buffer parameter N×(M+1) is 9000×(64+1). The dual-block grouping module converts the sampled data output from the sampling buffer module into 18000×64 sampled data using a dual-block grouping method. The frequency de-hopping module determines the frequency point f output by the frequency hopping pattern module. hopp (m) Generate frequency hopping point f hopp The local carrier (m) is used to perform frequency dehopping on the 18000th sampled data of the m-th block after double-block grouping; the frequency offset slotting module is based on the carrier Doppler frequency shift range. The carrier Doppler frequency shift is divided into (18+1) frequency sub-slots, and the carrier Doppler frequency shift search step is... The carrier Doppler frequency shift of the d-th frequency sub-slot is 100.0 kHz. for The compensation and correction module is based on the frequency hopping point f. hopp (m) and the carrier Doppler frequency shift output by the frequency offset slotting module Generate carrier Doppler frequency shift The local carrier performs carrier Doppler frequency shift compensation and correction on the m-th block of 18000 sampled data after frequency de-hopping; the CIC downsampling module's downsampling frequency f B For a frequency of 200.0kHz, the 18000th sampled data of the m-th block after compensation and correction is subjected to CIC downsampling processing to obtain 20 downsampled data. The zero-padding FFT module zero-padding the 20 downsampled data output by the CIC downsampling module to 64, and then performing a 64-point Fast Fourier Transform to obtain 64 Fast Fourier Transform data. The integration and accumulation module uses an incoherent integration method to perform 32 integrations and accumulations on the 64×32 Fast Fourier Transform data to obtain 64 integrated and accumulated data. The detection and calculation module uses a comparison search method on the integrated and accumulated data of all frequency sub-slots to obtain the sub-slot cycle d where the maximum peak value is located. vpp The index position k where the maximum peak value is located vpp Maximum peak integral accumulation data y vpp The two integral accumulation data points adjacent to the maximum peak value are y and y, respectively. - y + The exponential position k of the maximum peak value after correction is obtained by using a quadratic function interpolation correction method. max for Combined with the current frequency hopping point f hopp Calculate the carrier Doppler frequency shift f of the received signal. dopl for

[0044] It should be noted that, within the scope of protection defined in the claims of this invention, the following embodiments can be combined and / or extended or replaced in any logical manner from the above specific embodiments, such as the disclosed technical principles, disclosed technical features or implicitly disclosed technical features.

[0045] Example 1

[0046] A high-dynamic weak frequency-hopping signal carrier frequency measurement system includes:

[0047] The module includes a sampling buffer module, a dual-block grouping module, a frequency hopping pattern module, a frequency de-hopping module, a frequency offset slotting module, a compensation and correction module, a CIC downsampling module, a zero-padding FFT module, an integral accumulation module, and a detection and calculation module.

[0048] The sampling buffer module samples and buffers the received signal, controlling the read and write logic of the sampled data; the dual-block grouping module groups the sampled data output by the sampling buffer module into dual blocks; the frequency de-hopping module performs frequency de-hopping on the data after dual-block grouping according to the frequency hopping frequency point output by the frequency hopping pattern module; the frequency offset slotting module divides the carrier Doppler frequency shift into multiple frequency sub-slots according to the carrier Doppler frequency shift range; the compensation correction module compensates and corrects the data after frequency de-hopping according to the frequency hopping frequency point and the carrier Doppler frequency shift output by the frequency offset slotting module; the CIC downsampling module performs CIC downsampling processing on the compensated and corrected data; the zero-padding FFT module performs Fourier transform on the data after CIC downsampling using a zero-padding method; the integration accumulation module integrates and accumulates the Fourier transform data using an incoherent integration method to obtain integrated accumulated data; the detection and calculation module obtains the integrated peak information by using a comparison search method on all integrated accumulated data, and calculates the carrier Doppler frequency shift of the received signal according to the frequency hopping frequency point at the current time using a quadratic function interpolation correction method.

[0049] Example 2

[0050] Based on Example 1, the sampling data buffer parameter of the sampling buffer module is N×(M+1), where N is the total number of received signal sampling data in each frequency hopping time, satisfying N=f s / R fh f s R is the sampling rate of the received signal. fh Where M is the frequency hopping rate, and M is the number of integral accumulation points.

[0051] Example 3

[0052] Based on Example 2, the dual-block grouping module divides the N consecutive sampled data output by the sampling buffer module into one data block, and divides the N×(M+1) sampled data into data block 0, data block 1, ..., data block M-1, data block M. Using the dual-block grouping method, two consecutive data blocks are combined into one new data block, which is converted into 2N×M sampled data.

[0053] Example 4

[0054] Based on Example 1, the frequency de-hopping module uses the frequency hopping frequency f output by the frequency hopping pattern module. hopp (m), where m is the integral accumulation exponent, satisfying m∈(0,1,…,M-1), and is calculated using the formula CW. h o pp =-f h o pp (m)×2 32 / f s Data conversion is performed to obtain the frequency hopping control word CW. hopp For frequency control word CW hopp The query address is obtained by accumulating the data, and the frequency hopping frequency f is generated through address mapping and table lookup. hopp (m) local carrier, frequency hopping frequency f hopp The local carrier (m) is multiplied by the m-th block of 2N sampled data output by the dual-block grouping module to perform frequency dehopping on the data after dual-block grouping.

[0055] Example 5

[0056] Based on Example 1, the frequency offset slotting module is based on the carrier Doppler frequency shift range. The carrier Doppler frequency shift is divided into D+1 frequency sub-slots, where, This represents the minimum carrier Doppler frequency shift. The maximum value of the carrier Doppler frequency shift, and the carrier Doppler frequency shift search step. for Then the carrier Doppler frequency shift of the d-th frequency sub-slot for Where d is the frequency sub-slot search round, satisfying d∈(0,1,…,D).

[0057] Example 6

[0058] Based on Example 1, the compensation correction module adjusts the frequency based on the frequency hopping frequency f. hopp (m) and the carrier Doppler frequency shift output by the frequency offset slotting module Using calculation formula Perform data transformation, where f RF Given the radio frequency, the carrier Doppler frequency shift frequency control word is obtained. Frequency control word The query address is obtained by accumulating the data, and the carrier Doppler frequency shift is generated through address mapping and table lookup. Local carrier, carrier Doppler frequency shift The local carrier and frequency de-hopping module outputs the m-th block of 2N sampled data, and performs complex multiplication operation to compensate and correct the carrier Doppler frequency shift of the frequency de-hopping data.

[0059] Example 7

[0060] Based on Example 1, the CIC downsampling module adjusts the downsampling frequency f. B The calculation formula CW is used. B =f B / f s ×2 32 Data conversion is performed by generating a clearing pulse using a direct digital frequency synthesizer (DDS). An accumulator is used to continuously accumulate the compensated and corrected data. When the clearing pulse is valid, the accumulated value is output, and the data input to the accumulator is integrated and cleared. This process is repeated to complete the CIC downsampling processing of the m-th block of 2N sampled data output by the compensation and correction module.

[0061] Example 8

[0062] Based on Example 1, the zero-padding FFT module pads the downsampled data output by the CIC downsampled module with zeros to K, and performs a K-point fast Fourier transform on the K zero-padding data to obtain K fast Fourier transform data.

[0063] Example 9

[0064] Based on Example 1, the integration accumulation module uses an incoherent integration method to perform M integration accumulations on K×M fast Fourier transform data to obtain K integrated accumulation data.

[0065] Example 10

[0066] Based on Example 1, the detection and calculation module uses a comparison search method to obtain the sub-slot cycle d where the maximum peak value is located by integrating and accumulating the data of all frequency sub-slots. vpp The index position k where the maximum peak value is located vpp Maximum peak integral accumulation data y vpp The two integral accumulation data points adjacent to the maximum peak value are y and y, respectively. - y + The exponential position k of the maximum peak value after correction is obtained by using a quadratic function interpolation correction method. max for Combined with the current frequency hopping frequency f hoppCalculate the carrier Doppler frequency shift f of the received signal. dopl for

[0067] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0068] According to one aspect of the present invention, a computer program product or computer program is 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 the various optional implementations described above.

[0069] In another aspect, embodiments of the present invention also provide a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

[0070] All parts not covered in this invention are the same as or can be implemented using existing technologies.

[0071] The above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the application methods and principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the methods described in the above specific embodiments of the present invention. Therefore, the methods described above are only preferred and are not restrictive.

[0072] In addition to the examples above, other embodiments may be obtained by those skilled in the art based on the above disclosure or by making modifications using knowledge or technology in related fields. The features of each embodiment may be interchanged or replaced. Modifications and changes made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A high-dynamic weak frequency-hopping signal carrier frequency measurement system, characterized in that, include: The module includes a sampling buffer module, a dual-block grouping module, a frequency hopping pattern module, a frequency de-hopping module, a frequency offset slotting module, a compensation and correction module, a CIC downsampling module, a zero-padding FFT module, an integral accumulation module, and a detection and calculation module. The sampling buffer module samples and buffers the received signal, controlling the read and write logic of the sampled data; the dual-block grouping module groups the sampled data output by the sampling buffer module into dual blocks; the frequency de-hopping module de-hops the data after dual-block grouping according to the frequency hopping frequency point output by the frequency hopping pattern module; the frequency offset slotting module divides the carrier Doppler frequency shift into multiple frequency sub-slots according to the carrier Doppler frequency shift range; the compensation and correction module compensates and corrects the data after frequency de-hopping according to the frequency hopping frequency point and the carrier Doppler frequency shift output by the frequency offset slotting module; the CIC downsampling module performs CIC downsampling processing on the compensated and corrected data; the zero-padding FFT module performs Fourier transform on the data after CIC downsampling using a zero-padding method; the integration and accumulation module integrates and accumulates the Fourier transform data using an incoherent integration method to obtain integrated and accumulated data. The detection and calculation module uses a comparison search method to obtain the integral peak information of all integrated accumulated data, and uses a quadratic function interpolation correction method to calculate the carrier Doppler frequency shift of the received signal based on the frequency hopping point at the current time. The sampling data caching parameters of the sampling caching module are as follows: ,in, The total number of received signal sample data in each frequency hopping time, satisfying , The sampling rate of the received signal. For frequency hopping rate, To accumulate points; The dual-block grouping module will continuously output the sampling buffer module. Each sampled data point is divided into one data block. Each sampled data point is divided into data block 0, data block 1, ..., data block ... Data blocks The method of double-block grouping is used to combine two consecutive data blocks into a new data block, which is then converted into... One sampled data.

2. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The frequency de-hopping module determines the frequency hopping frequency output by the frequency hopping pattern module. ,in, The exponent for the accumulation of integrals satisfies Using the calculation formula Perform data conversion to obtain the frequency hopping control word. For frequency control words The query address is obtained by accumulating the values, and the frequency hopping frequency is generated through address mapping and table lookup. Local carrier, frequency hopping frequency The local carrier and the output of the dual-block packet module are the first piece The sampled data are subjected to complex multiplication, and the data after being divided into two blocks is subjected to frequency de-hopping.

3. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The frequency offset slotting module is based on the carrier Doppler frequency shift range. Divide the carrier Doppler frequency shift into There are frequency sub-slots, among which... This is the minimum value of the carrier Doppler frequency shift. The maximum value of the carrier Doppler frequency shift, and the carrier Doppler frequency shift search step. for Then the first Carrier Doppler shift of each frequency sub-slot for ,in, For the frequency sub-slot search round, satisfying .

4. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The compensation and correction module is based on the frequency hopping frequency. The carrier Doppler frequency shift output by the frequency offset slotting module Using the calculation formula Data transformation is performed, among which, Given the radio frequency, the carrier Doppler frequency shift frequency control word is obtained. For frequency control words The query address is obtained by accumulating the data, and the carrier Doppler frequency shift is generated through address mapping and table lookup. Local carrier, carrier Doppler frequency shift The output of the local carrier and frequency de-hopping module is the first piece The sampled data are multiplied by a complex multiplication operation, and the carrier Doppler frequency shift is compensated and corrected after frequency de-hopping.

5. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The CIC reduction module is based on the reduction frequency. Using the calculation formula Data conversion is performed, and a clearing pulse is generated using a direct digital frequency synthesizer (DDS). An accumulator continuously accumulates the compensated and corrected data. When the clearing pulse is valid, the accumulated value is output, and the data input to the accumulator is integrated and cleared. This process is repeated until the first data output from the compensation and correction module is cleared. piece Each sampled data point completes the CIC downsampling process.

6. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The zero-padding FFT module pads the reduced-data output from the CIC reduction module with zeros. One, to Each zero-padding data is used Point Fast Fourier Transform, to obtain Data from Fast Fourier Transform.

7. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The integration accumulation module employs an incoherent integration method for... Fast Fourier Transform data are processed By accumulating the integrals, we obtain The data is accumulated from each integral.

8. The high dynamic weak frequency hopping signal carrier frequency measurement system according to claim 1, characterized in that, The detection and calculation module uses a comparison search method to obtain the sub-slot cycle where the maximum peak value is located by integrating and accumulating the data of all frequency sub-slots. The index position where the maximum peak is located Maximum peak integral accumulation data The two integral accumulation data adjacent to the maximum peak are respectively , The exponential position of the maximum peak value after correction is obtained by using a quadratic function interpolation correction method. for Combined with the current frequency hopping frequency Calculate the carrier Doppler frequency shift of the received signal. for , This represents the minimum carrier Doppler frequency shift. Indicates the carrier Doppler frequency shift search step, This indicates a reduction in sampling frequency. Indicates radio frequency.

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