A method, system and terminal for single-bit radar dynamic range compensation based on generalized likelihood ratio test

Abstract

The present invention discloses a single-bit radar dynamic range compensation method, system and terminal based on generalized likelihood ratio test, the method comprising: obtaining an echo signal, and performing single-bit quantization processing to obtain a single-bit quantized signal; constructing a binary hypothesis model, and calculating the first source log-likelihood function and the second source log-likelihood function corresponding to the binary hypothesis model; using the zero-forcing method and the Newton method to compensate and update the first source log-likelihood function to obtain the first log-likelihood function; substituting the first interference echo into the second source log-likelihood function, and compensating and updating the second source log-likelihood function to obtain the second log-likelihood function; using the generalized likelihood ratio detection method to process the first log-likelihood function and the second log-likelihood function to obtain the generalized likelihood ratio target test statistic. The present invention can effectively filter out the first source, thereby improving the detection performance of weak sources and the single-bit dynamic detection range compensation.

Description

Technical Field

[0001] The present invention relates to the field of radar signal processing technology, and in particular to a single-bit radar dynamic range compensation method, system, terminal and computer-readable storage medium based on generalized likelihood ratio test. Background Art

[0002] Single-bit radar is a new radar system that uses single-bit ADC (Analog-to-Digital Converter) for data acquisition. It can achieve functions similar to traditional radars while reducing the size, cost and energy consumption of the radar system. It has unique advantages in breaking through system resource limitations. At present, research in the field of single-bit signal processing has covered many aspects, including arrival direction estimation, frequency estimation, and target tracking.

[0003] However, in the prior art, single-bit radars often lose signal amplitude, resulting in reduced ability to distinguish strong and weak signal sources, making it easier for weak targets to be masked by strong targets (such as interference sources), thereby reducing the dynamic detection range of the radar and causing inaccurate weak signal source detection results.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] The main purpose of the present invention is to provide a single-bit radar dynamic range compensation method, system, terminal and computer-readable storage medium based on generalized likelihood ratio test, aiming to solve the problem in the prior art that the single-bit radar often loses signal amplitude, resulting in reduced resolution of strong and weak signal sources, making it easier for weak targets to be masked by strong targets (such as interference sources), thereby reducing the dynamic detection range of the radar and inaccurate detection results of weak signal sources.

[0006] To achieve the above object, the present invention provides a single-bit radar dynamic range compensation method based on generalized likelihood ratio test, and the single-bit radar dynamic range compensation method based on generalized likelihood ratio test comprises the following steps:

[0007] Acquiring an echo signal, and performing single-bit quantization processing on the echo signal to obtain a single-bit quantized signal;

[0008] Constructing a binary hypothesis model according to the single-bit quantized signal, and calculating a log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function;

[0009] A first interference echo corresponding to a first information source is obtained by using a zero-forcing method and a Newton method, and a first log-likelihood function of the first information source is compensated and updated according to the first interference echo to obtain a first log-likelihood function;

[0010] Substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function;

[0011] The first log-likelihood function and the second log-likelihood function are processed using a generalized likelihood ratio detection method to obtain a generalized likelihood ratio target test statistic.

[0012] Optionally, the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, wherein the acquiring of the echo signal and performing single-bit quantization processing on the echo signal to obtain the single-bit quantized signal, specifically includes:

[0013] Determine the information source direction of the second information source, transmit a signal to the information source direction of the second information source according to a preset transmitting antenna, and receive an echo signal, wherein the expression of the echo signal is:

[0014] ;

[0015] in, To obtain the echo signal with the second source, for A complex matrix of dimension , is the number of receiving antennas, is the number of snapshots, is the second source echo, is the reflectivity of the second source, is the first source echo, is the reflectivity of the first source, is the array manifold of the second information source, is the array manifold of the first information source, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is a known transmission waveform, is additive white noise;

[0016] The echo signal is subjected to single-bit quantization processing to obtain a single-bit quantized signal, wherein the single-bit quantized signal is expressed as:

[0017] ;

[0018] in, is a single-bit quantized signal after single-bit quantization processing, is a single-bit quantization operation function, is the real part, is the imaginary part, is an imaginary unit, is a symbolic function.

[0019] Optionally, the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, wherein the step of constructing a binary hypothesis model according to the single-bit quantized signal and calculating a log-likelihood function corresponding to the binary hypothesis model specifically includes:

[0020] A second information source existence analysis is performed according to the single-bit quantized signal to obtain a binary hypothesis model, wherein the binary hypothesis model is expressed as:

[0021] ;

[0022] ;

[0023] in, is the assumption that there is no second information source in the single-bit quantized signal, It is the assumption that there is a second information source in the single-bit quantized signal;

[0024] Calculate the single-bit quantized signal at The log-likelihood function of the first source is obtained, and the single-bit quantized signal is calculated in The log-likelihood function of the case is used to obtain the log-likelihood function of the second source.

[0025] Optionally, the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, wherein the step of using the zero forcing method and the Newton method to obtain a first interference echo corresponding to a first information source, and compensating and updating the log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function, specifically includes:

[0026] Using a zero-forcing method to set the second information source in the single-bit quantized signal to zero, to obtain a simplified single-bit quantized signal, and to obtain a simplified log-likelihood function corresponding to the simplified single-bit quantized signal;

[0027] Using Newton's method to perform reflectivity estimation processing on the simplified log-likelihood function to obtain a first reflectivity corresponding to a first information source;

[0028] Performing maximum likelihood estimation iterative processing on the first reflectivity to obtain a first interference echo of the first information source;

[0029] The first information source log-likelihood function is compensated and updated according to the first interference echo to obtain a first log-likelihood function.

[0030] Optionally, in the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, the expression of the maximum likelihood estimation iterative processing is:

[0031] ;

[0032] in, is the first-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, is the second-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, For the The reflectivity corresponding to the sampling points is For the The reflectivity corresponding to the sampling points.

[0033] Optionally, the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, wherein the first interference echo is substituted into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and the second information source log-likelihood function is compensated and updated according to the second interference echo to obtain a second log-likelihood function, specifically includes:

[0034] Substituting the first interference echo into the second information source log-likelihood function to derive a second information source log-likelihood function;

[0035] Using the Newton method to perform reflectivity estimation processing on the derived second information source log-likelihood function to obtain a second reflectivity corresponding to the second information source;

[0036] Performing maximum likelihood estimation iterative processing on the second reflectivity to obtain a second interference echo of the second information source;

[0037] The second information source log-likelihood function is compensated and updated according to the second interference echo to obtain a second log-likelihood function.

[0038] Optionally, in the single-bit radar dynamic range compensation method based on generalized likelihood ratio test, the expression of the generalized likelihood ratio target test statistic is:

[0039] ;

[0040] in, is the generalized likelihood ratio target test statistic, is the first log-likelihood function, is the second log-likelihood function, for The column operation result is is the first interference echo, It is the second interference echo.

[0041] In addition, to achieve the above-mentioned purpose, the present invention further provides a single-bit radar dynamic range compensation system based on generalized likelihood ratio test, wherein the single-bit radar dynamic range compensation system based on generalized likelihood ratio test includes:

[0042] A single-bit quantization processing module, used to obtain an echo signal, and perform single-bit quantization processing on the echo signal to obtain a single-bit quantized signal;

[0043] A binary hypothesis model construction module, used to construct a binary hypothesis model according to the single-bit quantized signal, and calculate a log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function;

[0044] A first log-likelihood function generating module, used for acquiring a first interference echo corresponding to a first information source by using a zero-forcing method and a Newton method, and compensating and updating the log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function;

[0045] A second log-likelihood function generating module, used for substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function;

[0046] A generalized likelihood ratio detection module is used to process the first log-likelihood function and the second log-likelihood function using a generalized likelihood ratio detection method to obtain a generalized likelihood ratio target test statistic.

[0047] In addition, to achieve the above-mentioned purpose, the present invention also provides a terminal, wherein the terminal includes: a memory, a processor, and a single-bit radar dynamic range compensation program based on a generalized likelihood ratio test stored in the memory and executable on the processor, wherein the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test implements the steps of the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test as described above when the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test is executed by the processor.

[0048] In addition, to achieve the above-mentioned purpose, the present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a single-bit radar dynamic range compensation program based on a generalized likelihood ratio test, and when the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test is executed by a processor, the steps of the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test as described above are implemented.

[0049] In the present invention, an echo signal is obtained, and single-bit quantization processing is performed on the echo signal to obtain a single-bit quantized signal; a binary hypothesis model is constructed according to the single-bit quantized signal, and the log-likelihood function corresponding to the binary hypothesis model is calculated, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function; a first interference echo corresponding to a first information source is obtained by using a zero-forcing method and a Newton method, and the log-likelihood function of the first information source is compensated and updated according to the first interference echo to obtain a first log-likelihood function; the first interference echo is substituted into the log-likelihood function of the second information source to obtain a second interference echo corresponding to the second information source, and the log-likelihood function of the second information source is compensated and updated according to the second interference echo to obtain a second log-likelihood function; the first log-likelihood function and the second log-likelihood function are processed by a generalized likelihood ratio detection method to obtain a generalized likelihood ratio target test statistic. The present invention obtains a single-bit quantized signal by performing single-bit quantization processing on the received echo signal, and constructs a binary hypothesis model and a log-likelihood function according to the single-bit quantized signal. The strong signal source is estimated by adopting the zero-forcing method and the Newton method, and the interference of the strong signal source is effectively eliminated in the spatial spectrum, thereby reducing the sidelobe effect, which can effectively improve the accuracy of weak signal source detection, and further improve the dynamic detection range of the single-bit radar. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a flow chart of a preferred embodiment of a single-bit radar dynamic range compensation method based on generalized likelihood ratio test of the present invention;

[0051] Figure 2 It is a schematic diagram of spatial spectrograms of different detection statistics in a single-bit case of a preferred embodiment of a single-bit radar dynamic range compensation method based on a generalized likelihood ratio test of the present invention;

[0052] Figure 3 1 is a schematic diagram of the ROC of the detection statistic in the single-bit case of a preferred embodiment of the single-bit radar dynamic range compensation method based on the generalized likelihood ratio test of the present invention;

[0053] Figure 4 It is a structural diagram of a preferred embodiment of a single-bit radar dynamic range compensation system based on generalized likelihood ratio test of the present invention;

[0054] Figure 5 It is a structural diagram of a preferred embodiment of the terminal of the present invention. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0056] As radar systems gradually evolve towards small platforms, such as drones, small satellites, and smart cars, the constraints on system resources are becoming increasingly stringent. Single-bit compressed sampling simplifies analog-to-digital converters (ADCs) to the extreme, retaining only the symbol information for each measurement value. This not only relieves the burden on high-speed ADCs, but also reduces the total amount of data, thereby reducing the burden on data storage and processing. In terms of hardware, single-bit ADCs can be simplified to comparators, which have faster acquisition speeds and lower power consumption, and have outstanding advantages in simplifying systems, reducing costs, and improving efficiency. Single-bit radar is a new system radar that uses single-bit ADCs for data acquisition. It can achieve functions similar to traditional radars while reducing the size, cost, and energy consumption of radar systems, and has unique advantages in breaking through system resource constraints.

[0057] At present, single-bit signal processing technology has been widely used in many fields, such as arrival direction estimation, frequency estimation and target tracking. Studies have shown that through a properly designed signal processing algorithm, the degradation of system performance can still be controlled within a small range despite the existence of quantization effect. However, most existing radar target detection algorithms still do not fully consider the impact of single-bit quantization effect on system performance.

[0058] Although existing studies have preliminarily verified the detection performance of single-bit systems in simple scenarios such as a single signal source or white noise environment, and even under the same resource configuration, the detection effect of single-bit systems is better than that of high-bit systems in some scenarios. However, these methods are only applicable to relatively simple environments. Radar target detection usually involves more complex application scenarios, such as environments with multiple interference signals and non-uniform noise. Therefore, the applicability and performance of current single-bit radar detection technology in complex environments still need further research and improvement.

[0059] In summary, for the problem of dynamic range loss caused by the single-bit quantization effect in complex environments, proposing effective compensation and optimization strategies is the key to realizing the practical application of single-bit target detection technology. Therefore, designing a single-bit detection algorithm that can adapt to complex environments has important research value and practical significance.

[0060] The single-bit radar dynamic range compensation method based on generalized likelihood ratio test described in the preferred embodiment of the present invention is as follows: Figure 1 As shown, the single-bit radar dynamic range compensation method based on generalized likelihood ratio test includes the following steps:

[0061] Step S10: Acquire an echo signal, and perform single-bit quantization processing on the echo signal to obtain a single-bit quantized signal.

[0062] The present invention obtains a detection signal emitted by a transmitter of a radar system toward a target direction, and performs single-bit quantization processing on the received echo signal to obtain a corresponding single-bit quantized signal.

[0063] The first information source in the present invention is a strong target signal (or a strong interference source signal), and the second information source is a weak target signal.

[0064] Specifically, the information source direction of the second information source is determined, a signal is transmitted in the information source direction of the second information source according to a preset transmitting antenna, and an echo signal is received, wherein the expression of the echo signal is: ;in, To obtain the echo signal with the second source, for A complex matrix of dimension , is the number of receiving antennas, is the number of snapshots, is the second source echo, is the reflectivity of the second source, is the first source echo, is the reflectivity of the first source, is the array manifold of the second information source, is the array manifold of the first information source, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is a known transmission waveform, is additive white noise; performing single-bit quantization processing on the echo signal to obtain a single-bit quantized signal, wherein the single-bit quantized signal is expressed as: ;in, is a single-bit quantized signal after single-bit quantization processing, is a single-bit quantization operation function, is the real part, is the imaginary part, is an imaginary unit, is a symbolic function.

[0065] The radar system used in the present invention is a MIMO (Multiple Input Multiple Output) radar, and the transmitting antenna and transmitting antenna configured in the system transmit signals (transmit detection signals to the target angle) to a predetermined weak signal target (i.e., the second signal source in the present invention) to achieve effective target detection. For example, the MIMO radar system transmits a detection beam to the required angle through the transmitting antenna (at this time, it is assumed that there is a weak target in the environment of a strong signal source (i.e., the first signal source in the present invention)). For the transmitted detection beam, the present invention selects an orthogonal linear frequency modulation (LFM) signal as the transmission waveform S, which is expressed as ,in, It is sampling points, is the frequency modulation rate, is power, is a discrete time index, taking values =1, =1, = 1, noise is defined as having a mean of 0 and a variance of =2 Gaussian white noise, the detection echo signal received by the radar of the present invention is expressed as: in, is the acquired detection echo signal with the second information source (i.e., the echo signal in the present invention), for A complex matrix of dimension , is the number of receiving antennas, is the number of snapshots, is the second source echo, is the reflectivity of the second source, is the first source echo, is the reflectivity of the first source, is the array manifold of the second information source, is the array manifold of the first information source, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is a known transmission waveform, is additive white noise.

[0066] Furthermore, the present invention performs single-bit quantization processing on the echo signal to obtain a single-bit quantized signal , wherein the expression of the single-bit quantized signal is: ;in, is a single-bit quantized signal after single-bit quantization processing, is a single-bit quantization operation function, is the real part, is the imaginary part, is an imaginary unit, is a symbolic function.

[0067] The present invention uses the echo signal Single-bit quantization can simplify the analog-to-digital converter (ADC) to its extreme form, retaining only the sign information for each measured value. This not only eases the burden on the high-speed ADC, but also reduces the total amount of data, thereby reducing the burden on data storage and processing.

[0068] Step S20: construct a binary hypothesis model according to the single-bit quantized signal, and calculate the log-likelihood function corresponding to the binary hypothesis model.

[0069] The present invention is based on a single-bit quantized signal , establish a binary hypothesis model and , and calculate separately under each hypothesis ( : There is no assumption of a second source of information, : The corresponding log-likelihood function under the assumption that there is a second source. For example, based on a single-bit quantized signal, a binary hypothesis model is established and : ; After constructing the binary hypothesis model, the log-likelihood function can be solved according to the binary hypothesis model. After obtaining the log-likelihood function, the present invention can solve the maximum likelihood estimation of the unknown parameters according to the log-likelihood function.

[0070] Specifically, a second information source existence analysis is performed according to the single-bit quantized signal to obtain a binary hypothesis model, wherein the binary hypothesis model is expressed as: ; ;in, is the assumption that there is no second information source in the single-bit quantized signal, is the assumption that there is a second information source in the single-bit quantized signal; calculating the single-bit quantized signal in The log-likelihood function of the first source is obtained, and the single-bit quantized signal is calculated in The log-likelihood function of the case is used to obtain the log-likelihood function of the second source.

[0071] Among them, the first information source log-likelihood function is the log-likelihood function corresponding to the binary hypothesis model of the strong source signal (i.e., the first information source in the present invention), and the second information source log-likelihood function is the log-likelihood function corresponding to the binary hypothesis model of the weak source signal (i.e., the second information source in the present invention).

[0072] It is understandable that in Single-bit quantized signal The log-likelihood function can be expressed as: ,in, For the sampling points, is the number of samples of the received signal, is the log-likelihood function when there is a weak target (i.e., the second information source in the present invention), for The unknown parameters of the log-likelihood function in the case of is the real part of the variable, is the imaginary part of the variable, is the variance, where is the cumulative distribution function, is the detection threshold, is the integral variable; to simplify the expression, , , , , ,in is a columnar operator, and each variable is represented by a complex number. ;in ,and They are The real and imaginary parts of They are The real and imaginary parts of They are The real and imaginary parts of ,in .

[0073] The present invention can obtain The log-likelihood function of the single-bit quantized signal under the condition of quantization is obtained, and the log-likelihood function of the single-bit quantized signal is used in the generalized likelihood ratio test analysis.

[0074] Step S30: using the zero-forcing method and the Newton method to obtain a first interference echo corresponding to the first information source, and compensating and updating the log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function.

[0075] The present invention adopts the zero-forcing method and the Newton method to estimate the unknown parameters in the first information source and the second information source. The reflectivity of the first information source can be estimated by combining the zero-forcing method and the Newton method through the above-mentioned likelihood function. The estimated likelihood function (i.e., the first log-likelihood function in the present invention) can be expressed as , and through the estimated first source signal, combined with Newton's method, The lower likelihood function (i.e., the second log-likelihood function in the present invention) in the case of .

[0076] Specifically, the second information source in the single-bit quantized signal is set to zero using a zero-forcing method to obtain a simplified single-bit quantized signal, and a simplified log-likelihood function corresponding to the simplified single-bit quantized signal is obtained; the simplified log-likelihood function is processed for reflectivity estimation using the Newton method to obtain a first reflectivity corresponding to the first information source; the first reflectivity is iteratively processed using the maximum likelihood estimation to obtain a first interference echo of the first information source; the log-likelihood function of the first information source is compensated and updated according to the first interference echo to obtain a first log-likelihood function. The expression of the iterative processing of the maximum likelihood estimation is: ;in, is the first-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, is the second-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, For the The reflectivity corresponding to the sampling points is For the The reflectivity corresponding to the sampling points.

[0077] According to the zero-forcing concept, the present invention sets the second information source to zero when estimating the first information source echo. The binary hypothesis model can be simplified as follows: Since the first signal source will produce an obvious peak in the spatial spectrum, it can be considered that is known information, the likelihood function is: ,in , for The unknown parameters of the log-likelihood function in the case of For the updated A strong signal source. Among them, it can be seen that About is a convex function, therefore, Newton's method is used here to estimate the reflectivity of the first information source (that is, the first reflectivity corresponding to the first information source in the present invention) , according to Newton's method iteration formula, reflectivity The maximum likelihood estimation iterative formula can be expressed as: , represents the log-likelihood function (i.e., the first source log-likelihood function in the present invention) Relative to The first-order partial derivative of the unknown parameter, and represents the log-likelihood function Relative to unknown parameters The second-order partial derivative of . , the iteration ends, then the reflectivity The maximum likelihood estimate of is (i.e., the first interference echo in the present invention), the likelihood function Can be updated to (ie, the first source log-likelihood function is updated to the first log-likelihood function).

[0078] Step S40: Substitute the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensate and update the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function.

[0079] Specifically, the first interference echo is substituted into the second information source log-likelihood function to obtain a derived second information source log-likelihood function; the derived second information source log-likelihood function is processed for reflectivity estimation using the Newton method to obtain a second reflectivity corresponding to the second information source; the second reflectivity is iteratively processed by maximum likelihood estimation to obtain a second interference echo of the second information source; the second information source log-likelihood function is compensated and updated according to the second interference echo to obtain a second log-likelihood function.

[0080] The present invention brings the estimated first source echo into In the likelihood function of the case, the detector is re-derived, and now The likelihood function of the received signal in the case (i.e., the derived second source log-likelihood function in the present invention) is: ,in, , ,in, is a columnar operator, and each variable is represented by a complex number. For the updated , For the updated , Then it can be seen that About is a convex function, so Newton's method is used here to estimate the reflectivity of the first source (i.e., the second reflectivity corresponding to the second information source in the present invention), according to the Newton method iteration formula, the parameter estimation can be expressed as: ,in, Represents the log-likelihood function Relative to The first-order partial derivatives of the unknown parameters, The expression is: ,in, The specific representation is as follows:

[0081] ; ,and represents the log-likelihood function Relative to unknown parameters The second-order partial derivative of The expression is: ,in , , The specific expression is as follows:

[0082] ;

[0083] ;

[0084] ;in, , , , ,in, , , as well as It is only used to abbreviate formulas and refer to combinations of formulas.

[0085] when , then the iteration ends, then the reflectivity The maximum likelihood estimate of (i.e., the second reflectivity in the present invention) is (i.e., the second interference echo in the present invention), the likelihood function Can be updated to (That is, the second information source log-likelihood function is updated to the second log-likelihood function.) In the present invention, both step S30 and step S40 are used for estimating unknown parameters and for calculating the generalized likelihood ratio test statistic.

[0086] Step S50: Use a generalized likelihood ratio detection method to process the first log-likelihood function and the second log-likelihood function to obtain a generalized likelihood ratio target test statistic.

[0087] The present invention reconstructs the unknown parameters according to the estimation. and The log-likelihood function under is reconstructed (the first log-likelihood function and the second log-likelihood function are reconstructed), and these reconstructed log-likelihood functions are used to calculate the asymptotically optimal generalized likelihood ratio test statistic. Further, according to the estimated and The log-likelihood function and the asymptotically optimal detection method under the condition of , we obtain the asymptotically optimal generalized likelihood ratio target test statistic (also called the generalized likelihood ratio weak target test statistic or the generalized likelihood ratio second source test statistic).

[0088] Among them, the present invention can obtain the generalized likelihood ratio target test statistic through the generalized likelihood ratio method, which can be expressed as: At this time, the detection statistic obtained by the present invention is the statistic with the best performance.

[0089] Specifically, the expression of the generalized likelihood ratio target test statistic is:

[0090] ;in, is the generalized likelihood ratio target test statistic, is the first log-likelihood function, is the second log-likelihood function, for The column operation result is is the first interference echo, It is the second interference echo.

[0091] The present invention is based on the estimated and The log-likelihood function and the definition of the generalized likelihood ratio test under , where the generalized likelihood ratio target test statistic can be expressed as: Furthermore, after obtaining the generalized likelihood ratio small target test statistic, the present invention performs spatial spectrum drawing and ROC graph drawing to obtain the detection result of the generalized likelihood ratio small target test statistic.

[0092] The effect of the present invention can be further illustrated by simulation experiments. Experiment 1 and Experiment 2 are set in the present invention.

[0093] Among them, Experiment 1 correctly shows the spatial spectrum of different detection statistics: In this simulation experiment, the number of antennas is set to 256, the number of samples is set to 1024, the angles of the first source and the second source are set to 60° and 45° respectively, and the angle of drawing the spatial spectrum is set to 0~90°. And the detection statistic in the existing comparison method is known to be ,like Figure 2 As shown, the detection statistic derived in the present invention can eliminate the first information source, reduce the side lobe of the second information source and enhance the detection effect of the second information source.

[0094] Among them, Experiment 2 correctly displays the ROC graph of different detection statistics: In this simulation, considering the detection threshold range is 0~1, and the detection interval is 0.00001, the Monte Carlo number is 105, the number of antennas is 256, and the number of samples is 1024, as shown in Figure 3 As shown, it can be seen that the detection performance derived by the present invention is better.

[0095] In summary, the present invention combines the zero forcing method and the Newton method to estimate the unknown parameters in the first information source and the second information source, and reconstructs and and The log-likelihood functions of the cases are reconstructed, and the asymptotically optimal generalized likelihood ratio test statistics are calculated using these reconstructed log-likelihood functions. Compared with similar detectors, the present invention can effectively filter out the first information source in the spatial domain, thereby improving the detection performance of the second information source and thus compensating for the single-bit dynamic detection range.

[0096] Furthermore, if Figure 4 As shown, based on the above-mentioned single-bit radar dynamic range compensation method based on generalized likelihood ratio test, the present invention also provides a single-bit radar dynamic range compensation system based on generalized likelihood ratio test, wherein the single-bit radar dynamic range compensation system based on generalized likelihood ratio test includes:

[0097] The single-bit quantization processing module 51 is used to obtain an echo signal and perform single-bit quantization processing on the echo signal to obtain a single-bit quantized signal;

[0098] A binary hypothesis model construction module 52, configured to construct a binary hypothesis model according to the single-bit quantized signal, and calculate a log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function;

[0099] A first log-likelihood function generating module 53 is used to obtain a first interference echo corresponding to a first information source by using a zero-forcing method and a Newton method, and to compensate and update the first information source log-likelihood function according to the first interference echo to obtain a first log-likelihood function;

[0100] A second log-likelihood function generating module 54 is used to substitute the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensate and update the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function;

[0101] The generalized likelihood ratio detection module 55 is used to process the first log-likelihood function and the second log-likelihood function using a generalized likelihood ratio detection method to obtain a generalized likelihood ratio target test statistic.

[0102] Furthermore, if Figure 5 As shown, based on the above-mentioned single-bit radar dynamic range compensation method and system based on generalized likelihood ratio test, the present invention also provides a terminal accordingly, and the terminal includes a processor 10, a memory 20 and a display 30. Figure 5Only some components of the terminal are shown, but it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0103] In some embodiments, the memory 20 may be an internal storage unit of the terminal, such as a hard disk or memory of the terminal. In other embodiments, the memory 20 may also be an external storage device of the terminal, such as a plug-in hard disk, a smart memory card (Smart Media Card, SMC), a secure digital (SecureDigital, SD) card, a flash card (Flash Card), etc. equipped on the terminal. Further, the memory 20 may also include both an internal storage unit of the terminal and an external storage device. The memory 20 is used to store application software and various types of data installed on the terminal, such as the program code of the installation terminal. The memory 20 may also be used to temporarily store data that has been output or is to be output. In one embodiment, a single-bit radar dynamic range compensation program 40 based on a generalized likelihood ratio test is stored on the memory 20, and the single-bit radar dynamic range compensation program 40 based on a generalized likelihood ratio test can be executed by the processor 10, thereby realizing the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test in the present application.

[0104] In some embodiments, the processor 10 may be a central processing unit (CPU), a microprocessor or other data processing chip, used to run the program code or process data stored in the memory 20, such as executing the single-bit radar dynamic range compensation method based on generalized likelihood ratio test.

[0105] In some embodiments, the display 30 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 30 is used to display information on the terminal and to display a visual user interface. The terminals communicate with each other via a system bus.

[0106] In one embodiment, when the processor 10 executes the single-bit radar dynamic range compensation program 40 based on generalized likelihood ratio test in the memory 20, the steps of the single-bit radar dynamic range compensation method based on generalized likelihood ratio test as described above are implemented.

[0107] The present invention also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a single-bit radar dynamic range compensation program based on a generalized likelihood ratio test, and when the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test is executed by a processor, the steps of the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test as described above are implemented.

[0108] In summary, the present invention provides a single-bit radar dynamic range compensation method, system and terminal based on generalized likelihood ratio test, the method comprising: obtaining an echo signal, and performing single-bit quantization processing on the echo signal to obtain a single-bit quantized signal; constructing a binary hypothesis model according to the single-bit quantized signal, and calculating the log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function comprises a first information source log-likelihood function and a second information source log-likelihood function; using a zero-forcing method and a Newton method to obtain a first interference echo corresponding to a first information source, and compensating and updating the first information source log-likelihood function according to the first interference echo to obtain a first log-likelihood function; substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function; using a generalized likelihood ratio detection method to process the first log-likelihood function and the second log-likelihood function to obtain a generalized likelihood ratio target test statistic. The present invention obtains a single-bit quantized signal by performing single-bit quantization processing on the received echo signal, and constructs a binary hypothesis model and a log-likelihood function according to the single-bit quantized signal. The first information source is estimated by adopting the zero-forcing method and the Newton method, and the interference of the first information source is effectively eliminated in the spatial spectrum, thereby reducing the sidelobe effect, and can effectively improve the accuracy of the second information source signal detection, thereby also improving the dynamic detection range of the single-bit radar.

[0109] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or terminal including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or terminal including the element.

[0110] Of course, those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the program can be stored in a computer-readable storage medium that can be read by a computer, and the program can include the processes of the above-mentioned method embodiments when executed. The computer-readable storage medium can be a memory, a disk, an optical disk, etc.

[0111] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A single-bit radar dynamic range compensation method based on generalized likelihood ratio test, characterized in that: The single-bit radar dynamic range compensation method based on generalized likelihood ratio test includes: Acquiring an echo signal, and performing single-bit quantization processing on the echo signal to obtain a single-bit quantized signal; Constructing a binary hypothesis model according to the single-bit quantized signal, and calculating a log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function; A first interference echo corresponding to a first information source is obtained by using a zero-forcing method and a Newton method, and a first log-likelihood function of the first information source is compensated and updated according to the first interference echo to obtain a first log-likelihood function; The method of acquiring a first interference echo corresponding to a first information source by using a zero-forcing method and a Newton method, and compensating and updating a log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function specifically includes: Using a zero-forcing method to set the second information source in the single-bit quantized signal to zero, to obtain a simplified single-bit quantized signal, and to obtain a simplified log-likelihood function corresponding to the simplified single-bit quantized signal; Using Newton's method to perform reflectivity estimation processing on the simplified log-likelihood function to obtain a first reflectivity corresponding to a first information source; Performing maximum likelihood estimation iterative processing on the first reflectivity to obtain a first interference echo of the first information source; Compensating and updating the first information source log-likelihood function according to the first interference echo to obtain a first log-likelihood function; The expression of the maximum likelihood estimation iterative process is: ； in, is the first-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, is the second-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, For the The reflectivity corresponding to the sampling points is For the The reflectivity corresponding to the sampling points; Substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function; Substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function specifically includes: Substituting the first interference echo into the second information source log-likelihood function to derive a second information source log-likelihood function; Using the Newton method to perform reflectivity estimation processing on the derived second information source log-likelihood function to obtain a second reflectivity corresponding to the second information source; Performing maximum likelihood estimation iterative processing on the second reflectivity to obtain a second interference echo of the second information source; Compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function; The unknown parameters of the first information source and the second information source are estimated by using the zero forcing method and the Newton method; According to the estimated unknown parameters, the first log-likelihood function and the second log-likelihood function are reconstructed, and the asymptotically optimal generalized likelihood ratio test statistic is calculated using these reconstructed log-likelihood functions; According to Newton's method iteration formula, parameter estimation is expressed as: ,in, For the The second reflectivity corresponding to the sampling points is For the The second reflectivity corresponding to the sampling points is represents the first-order partial derivative of the second source log-likelihood function with respect to the second reflectivity, The expression is: ,in, The specific representation is as follows: ; ,in, For the sampling points, is the number of samples of the received signal, for The unknown parameters of the log-likelihood function in the case of is the assumption that there is a second information source in the single-bit quantized signal, is the real part of the variable, is the imaginary part of the variable, is the variance, is the matrix transpose, is the transmit beam azimuth, is the cumulative distribution function, is the detection threshold, is the integral variable; among them, take , , , , is the reflectivity of the first source, ,in, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is the array manifold of the second information source, is the array manifold of the first information source, is a known transmission waveform, is a columnar operator, and each variable is represented by a complex number. ,in ,and They are The real and imaginary parts of They are The real and imaginary parts of They are The real and imaginary parts of For the updated , For the updated ,and ,in ,and represents the second-order partial derivative of the second source log-likelihood function with respect to the second reflectivity, The expression is: ,in , , The specific expression is as follows: ； ； ;in, , , , ; Using a generalized likelihood ratio detection method to process the first log-likelihood function and the second log-likelihood function to obtain a generalized likelihood ratio target test statistic; The expression of the generalized likelihood ratio target test statistic is: ； in, is the generalized likelihood ratio target test statistic, is the first log-likelihood function, is the second log-likelihood function, for The column operation result is is a single-bit quantized signal after single-bit quantization processing, is the first interference echo, It is the second interference echo.

2. The single-bit radar dynamic range compensation method based on generalized likelihood ratio test according to claim 1, characterized in that: The acquiring of the echo signal and performing single-bit quantization processing on the echo signal to obtain a single-bit quantized signal specifically includes: Determine the information source direction of the second information source, transmit a signal to the information source direction of the second information source according to a preset transmitting antenna, and receive an echo signal, wherein the expression of the echo signal is: ； in, To obtain the echo signal with the second information source, for A complex matrix of dimension , is the number of receiving antennas, is the number of snapshots, is the second source echo, is the reflectivity of the second source, is the first source echo, is the reflectivity of the first source, is the array manifold of the second information source, is the array manifold of the first information source, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is a known transmission waveform, is additive white noise; The echo signal is subjected to single-bit quantization processing to obtain a single-bit quantized signal, wherein the single-bit quantized signal is expressed as: ； in, is a single-bit quantized signal after single-bit quantization processing, is a single-bit quantization operation function, is the real part, is the imaginary part, is an imaginary unit, is a symbolic function.

3. The single-bit radar dynamic range compensation method based on generalized likelihood ratio test according to claim 2, characterized in that: The step of constructing a binary hypothesis model according to the single-bit quantized signal and calculating a log-likelihood function corresponding to the binary hypothesis model specifically includes: A second information source existence analysis is performed according to the single-bit quantized signal to obtain a binary hypothesis model, wherein the binary hypothesis model is expressed as: ； ； in, is the assumption that there is no second information source in the single-bit quantized signal, It is the assumption that there is a second information source in the single-bit quantized signal; Calculate the single-bit quantized signal at The log-likelihood function of the first source is obtained, and the single-bit quantized signal is calculated in The log-likelihood function of the case is used to obtain the log-likelihood function of the second source.

4. A single-bit radar dynamic range compensation system based on generalized likelihood ratio test, characterized in that: The single-bit radar dynamic range compensation system based on generalized likelihood ratio test includes: A single-bit quantization processing module, used to obtain an echo signal, and perform single-bit quantization processing on the echo signal to obtain a single-bit quantized signal; A binary hypothesis model construction module, used to construct a binary hypothesis model according to the single-bit quantized signal, and calculate a log-likelihood function corresponding to the binary hypothesis model, wherein the log-likelihood function includes a first information source log-likelihood function and a second information source log-likelihood function; A first log-likelihood function generating module, used for acquiring a first interference echo corresponding to a first information source by using a zero-forcing method and a Newton method, and compensating and updating the log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function; The method of acquiring a first interference echo corresponding to a first information source by using a zero-forcing method and a Newton method, and compensating and updating a log-likelihood function of the first information source according to the first interference echo to obtain a first log-likelihood function specifically includes: Using a zero-forcing method to set the second information source in the single-bit quantized signal to zero, to obtain a simplified single-bit quantized signal, and to obtain a simplified log-likelihood function corresponding to the simplified single-bit quantized signal; Using Newton's method to perform reflectivity estimation processing on the simplified log-likelihood function to obtain a first reflectivity corresponding to a first information source; Performing maximum likelihood estimation iterative processing on the first reflectivity to obtain a first interference echo of the first information source; Compensating and updating the first information source log-likelihood function according to the first interference echo to obtain a first log-likelihood function; The expression of the maximum likelihood estimation iterative process is: ； in, is the first-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, is the second-order partial derivative of the log-likelihood function of the first source with respect to the first reflectivity, For the The reflectivity corresponding to the sampling points is For the The reflectivity corresponding to the sampling points; A second log-likelihood function generating module, used for substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function; Substituting the first interference echo into the second information source log-likelihood function to obtain a second interference echo corresponding to the second information source, and compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function specifically includes: Substituting the first interference echo into the second information source log-likelihood function to derive a second information source log-likelihood function; Using the Newton method to perform reflectivity estimation processing on the derived second information source log-likelihood function to obtain a second reflectivity corresponding to the second information source; Performing maximum likelihood estimation iterative processing on the second reflectivity to obtain a second interference echo of the second information source; Compensating and updating the second information source log-likelihood function according to the second interference echo to obtain a second log-likelihood function; The unknown parameters of the first information source and the second information source are estimated by using the zero forcing method and the Newton method; According to the estimated unknown parameters, the first log-likelihood function and the second log-likelihood function are reconstructed, and the asymptotically optimal generalized likelihood ratio test statistic is calculated using these reconstructed log-likelihood functions; According to Newton's method iteration formula, parameter estimation is expressed as: ,in, For the The second reflectivity corresponding to the sampling points is For the The second reflectivity corresponding to the sampling points is represents the first-order partial derivative of the second source log-likelihood function with respect to the second reflectivity, The expression is: ,in, The specific representation is as follows: ; ,in, For the sampling points, is the number of samples of the received signal, for The unknown parameters of the log-likelihood function in the case of is the assumption that there is a second information source in the single-bit quantized signal, is the real part of the variable, is the imaginary part of the variable, is the variance, is the matrix transpose, is the transmit beam azimuth, is the cumulative distribution function, is the detection threshold, is the integral variable; among them, take , , , , is the reflectivity of the first source, ,in, is the transmit beam azimuth of the second information source, is the transmit beam azimuth of the first information source, is the array manifold of the second information source, is the array manifold of the first information source, is a known transmission waveform, is a columnar operator, and each variable is represented by a complex number. ,in ,and They are The real and imaginary parts of They are The real and imaginary parts of They are The real and imaginary parts of For the updated , For the updated ,and ,in ,and represents the second-order partial derivative of the second source log-likelihood function with respect to the second reflectivity, The expression is: ,in , , The specific expression is as follows: ； ； ;in, , , , ; A generalized likelihood ratio detection module, configured to process the first log-likelihood function and the second log-likelihood function using a generalized likelihood ratio detection method to obtain a generalized likelihood ratio target test statistic; The expression of the generalized likelihood ratio target test statistic is: ； in, is the generalized likelihood ratio target test statistic, is the first log-likelihood function, is the second log-likelihood function, for The column operation result is is a single-bit quantized signal after single-bit quantization processing, is the first interference echo, It is the second interference echo.

5. A terminal, characterized in that: The terminal includes: a memory, a processor, and a single-bit radar dynamic range compensation program based on a generalized likelihood ratio test stored in the memory and executable on the processor. When the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test is executed by the processor, the steps of the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test as described in any one of claims 1 to 3 are implemented.

6. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a single-bit radar dynamic range compensation program based on a generalized likelihood ratio test. When the single-bit radar dynamic range compensation program based on a generalized likelihood ratio test is executed by a processor, the steps of the single-bit radar dynamic range compensation method based on a generalized likelihood ratio test as described in any one of claims 1 to 3 are implemented.

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