A radar pulse signal adaptive detection method and system

Abstract

The invention relates to the field of radar pulse signal detection, and in particular to an adaptive detection method and system for radar pulse signals. The method divides raw data into two paths, processes pre-processed data therein to obtain IQ data, calculates amplitude mean data according to the IQ data, and then copies the amplitude mean data into A unit data and B unit data. The A unit data is calculated to obtain a rising edge amplitude comparison value, a falling edge amplitude comparison value and a moment when a pulse signal mark exists. Then, the B unit data is compared with the rising edge amplitude comparison value and the falling edge amplitude comparison value, so that the final radar signal parameter is calculated by the adaptively obtained rising edge amplitude comparison value and the falling edge amplitude comparison value, so that the final radar pulse signal obtained is more accurate. The method solves the problem in the prior art that the threshold is difficult to be adaptively changed according to different environments, thereby resulting in low detection accuracy of the pulse signal.

Description

Technical Field

[0001] The present invention relates to the field of radar pulse signal detection, and in particular to an adaptive detection method and system for radar pulse signals. Background Art

[0002] At present, the constant false alarm processing method is commonly used. The CFAR processing technology is a signal processing algorithm that provides a detection threshold for the detection strategy in the radar automatic detection system and minimizes the influence of clutter and interference on the false alarm probability of the system. According to the method of forming the detection threshold, it can be summarized as follows: 1) a fixed threshold; 2) a threshold formed according to the average amplitude of external interference; 3) a threshold formed on the basis of obtaining some prior information on the statistical distribution of interference; 4) a threshold formed for the statistical hypothesis test of distribution freedom when there is no prior information on the statistical distribution of interference.

[0003] The corresponding defects of the existing technology are mainly as follows: 1. When the fixed threshold is too low, false alarms are likely to occur when the clutter is too large; when the fixed threshold is too high, small signals are lost, resulting in missed alarms; 2. The real field environment is complex: electromagnetic clutter and active interference are innumerable, and using the average amplitude as the threshold will cause erroneous results; 3. In the real battlefield, due to the complex electromagnetic environment and unknown enemy equipment, it is impossible to accurately detect using prior statistical information as the threshold; 4. The threshold formed by the free statistical hypothesis test will cause false alarms and missed alarms. Therefore, the threshold in the existing technology is difficult to adaptively change according to different environments, resulting in low detection accuracy of pulse signals. Summary of the invention

[0004] In view of the deficiencies of the prior art, the present invention provides an adaptive detection method and system for radar pulse signals, which solves the problem in the prior art that the threshold is difficult to adaptively change according to different environments, resulting in low detection accuracy of pulse signals.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] An adaptive detection method for radar pulse signals, the detection method comprising the following steps:

[0007] S1. Obtain the original data containing the radar pulse signal through FPGA, and copy the original data into two paths, one path is backup data, and the other path is channelized to obtain pre-processed data;

[0008] S2. Starting from the first data in the preprocessed data, select a number of continuous real numbers in sequence, and set a number of corresponding angles to perform trigonometric function transformation on them to obtain IQ data;

[0009] S3, sequentially calculating the amplitude absolute value of each data in the IQ data to obtain amplitude absolute value data, and sequentially calculating the amplitude mean of each of several data in the amplitude absolute value data to obtain amplitude mean data, and copying the amplitude mean data into A unit data and B unit data;

[0010] S4, starting from the first data, sequentially calculating the data accumulation value of each m consecutive data in the A unit data to obtain data accumulation value data, and taking the data accumulation value data of the current clock as the dividend and dividing it with the data accumulation value at least m-1 clocks before in the FPGA to calculate the accumulation value ratio, to obtain accumulation value ratio data;

[0011] S5, performing multiple expansion, logarithm and subtraction operations on the accumulated value ratio data in sequence to obtain error reduction data;

[0012] S6, setting a fixed value, and calculating the difference between the error reduction data and the fixed value to mark the moment when the pulse signal exists, and judging the pulse signal moment including the rising edge, the falling edge, and the pulse mark without the rising edge and the falling edge according to the amplitude value of the B unit data and the rising edge amplitude comparison value and the falling edge amplitude comparison value;

[0013] S7. Calculate the pulse description word through FPGA according to the pulse mark of the B unit data, fuse and sort it with the backup data to obtain the radar signal parameters and output them.

[0014] Preferably, in step S2, the following steps are specifically included:

[0015] S21, starting from the first real number in the preprocessed data, sequentially obtaining a number of consecutive real numbers;

[0016] S22, setting a number of conversion angles corresponding to the same number of consecutive real numbers;

[0017] S23. Calculate a number of continuous real numbers in sequence according to the conversion angle, and arrange them in order to obtain IQ data; the expression of any IQ data is: ,in , in the above formula, is the preprocessed data before transformation, To convert the angle.

[0018] Preferably, in step S3, the following steps are specifically included:

[0019] S31, calculating the absolute value of the amplitude of each data in the IQ data to obtain the absolute value of the amplitude data; the calculation formula of the absolute value of the amplitude is:

[0020] ;

[0021] in, Indicates the absolute value of the amplitude of a single IQ data. and Respectively represent the number with a larger absolute value and the number with a smaller absolute value of the real part and the imaginary part of a single IQ data;

[0022] S32, sequentially calculating the amplitude mean of each of the plurality of data in the amplitude absolute value data, and forming amplitude mean data in order; the calculation formula of the amplitude mean is:

[0023] ;

[0024] In the above formula, represents the mean amplitude, Indicates the number of selected continuous absolute value amplitude data. Represents the i-th data in the selected amplitude absolute value data;

[0025] S33. Copy the amplitude mean data into A unit data and B unit data.

[0026] Preferably, in step S4, the following steps are specifically included:

[0027] S41, starting from the first data, sequentially calculate the data accumulation value of each m consecutive data in the A unit data; the calculation formula of the data accumulation value is:

[0028] ;

[0029] In the above formula, Indicates the data accumulation value of every m consecutive data in the A unit data. It represents the i-th data selected from the A unit data, which is the amplitude mean. The number of selected continuous data is indivual;

[0030] S42, sequentially determine whether the current data accumulation value of the A unit data is the mth clock and later in the FPGA;

[0031] If yes, proceed to step S43;

[0032] If not, the current data accumulation value is discarded;

[0033] S43, taking the current data accumulated value as the dividend and dividing it with the data accumulated value at least m-1 clocks before the current one in the FPGA to calculate the accumulated value ratio, and arranging them in order to obtain accumulated value ratio data; the calculation formula of the accumulated value ratio is:

[0034] ;

[0035] In the above formula, Indicates the ratio of cumulative values, is the accumulated value of the current clock, Indicates the accumulated value in the FPGA before a certain clock.

[0036] Preferably, in step S5, the following steps are specifically included:

[0037] S51, sequentially enlarging any data in the accumulated value ratio data by A times;

[0038] S52, calculating the logarithm of the ratio of the accumulated values ​​after the expansion by A times; the calculation formula of the logarithm is:

[0039] ;

[0040] In the above formula, The logarithm of the ratio of the accumulated value after expanding by A times is calculated by taking the logarithm. is the expansion factor, is the i-th data in the cumulative value ratio data after being expanded A times;

[0041] S53. Subtract C from the obtained logarithm to eliminate the numerical increase when it is enlarged by A times, and obtain error reduction data.

[0042] Preferably, in step S6, the following steps are specifically included:

[0043] S61, setting a fixed value;

[0044] S62, determining in turn whether each error reduction data is greater than a fixed value;

[0045] If yes, the time corresponding to the error reduction data is marked as the presence of a pulse signal;

[0046] If not, the time corresponding to the error reduction data is marked as no pulse signal;

[0047] S63, calculating the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value according to the A unit data;

[0048] S64, sequentially comparing the amplitude value of the B unit data that does not contain the no-pulse signal mark with the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value;

[0049] If the amplitude value is greater than or equal to the pulse rising edge amplitude comparison value, then the moment is marked as the pulse mark of the rising edge;

[0050] If the amplitude value is less than or equal to the pulse falling edge amplitude comparison value, then the moment is marked as the pulse mark of the falling edge;

[0051] If the amplitude value is between the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value, it is marked as a pulse mark without rising edge and falling edge.

[0052] Preferably, in step S61, the following steps are specifically included:

[0053] S611, placing the FPGA in a real environment to be used without radar pulse signals;

[0054] S612, connecting the FPGA to a regulated power supply and measuring the amplitude of the pulse signal at any time in the real environment;

[0055] S613, calculating the absolute values ​​of the maximum and minimum values ​​of the pulse signal amplitude to obtain the amplitude range;

[0056] S614, the amplitude range is equally divided into a number of range steps, and the amplitude density of any pulse signal amplitude within the range step is calculated; the calculation formula of the amplitude density is:

[0057] ;

[0058] in,

[0059] ;

[0060] In the above formula, It represents the amplitude density of the i-th pulse signal within the extreme difference step. is the symbolic function, and are the i-th and j-th pulse signal amplitudes respectively, k represents the number of pulse signal amplitudes, represents the equal division coefficient, is the range of the pulse signal amplitude, That is the extreme step distance;

[0061] S615, calculating the average value of the amplitudes of several pulse signals with the largest pulse density to obtain a fixed value.

[0062] Preferably, in step S63, the following steps are specifically included:

[0063] S631, obtaining the pulse amplitude high value and pulse amplitude low value of the A unit data;

[0064] S632, calculating the pulse amplitude middle value according to the pulse amplitude high value and the pulse amplitude low value; the calculation formula of the pulse amplitude middle value is:

[0065] ;

[0066] In the above formula, Indicates the middle value of the pulse amplitude, Indicates the high value of pulse amplitude, Indicates low value of pulse amplitude;

[0067] S633, calculate the pulse rising edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse rising edge amplitude comparison value is:

[0068] ;

[0069] In the above formula, Indicates the pulse rising edge amplitude comparison value, and They are high value coefficient and low value coefficient, and their values ​​are generally 0.75 and 0.25 respectively;

[0070] S634. Calculate the pulse falling edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse falling edge amplitude comparison value is:

[0071] ;

[0072] In the above formula, Indicates the pulse falling edge amplitude comparison value, is the falling edge coefficient, Generally it is 0.25.

[0073] Preferably, in step S2, the number of the continuous real numbers and the conversion angles are both 4, and the values ​​of the conversion angles corresponding to the 4 continuous real numbers are 0°, 90°, 180° and 270°.

[0074] The technical solution also provides a system for implementing an adaptive detection method for radar pulse signals, the system comprising: a processor and a memory, the memory being used to store a computer program, and the computer program implementing any one of the adaptive detection methods when executed by the processor.

[0075] Compared with the prior art, the present invention provides an adaptive detection method and system for radar pulse signals, which has the following beneficial effects:

[0076] 1. The present invention divides the original data into two paths, processes the pre-processed data therein to obtain IQ data, then calculates the amplitude mean data according to the IQ data, and then copies the amplitude mean data into A unit data and B unit data, and then calculates the A unit data to obtain the rising edge amplitude comparison value, the falling edge amplitude comparison value and the moment when the pulse signal mark exists, and then compares the B unit data with the rising edge amplitude comparison value and the falling edge amplitude comparison value, so as to obtain the final radar signal parameters through the adaptively obtained rising edge amplitude comparison value and the falling edge amplitude comparison value calculation, so that the final radar pulse signal obtained is more accurate.

[0077] 2. The present invention obtains 4 consecutive real numbers each time and converts them into IQ data, and sets the conversion angles to 0°, 90°, 180° and 270°. This ensures that the real and imaginary parts of the IQ data are integers while ensuring the maximum data processing volume, thereby ensuring the real-time calculation speed of the FPGA.

[0078] 3. The present invention first expands the accumulated value ratio by A times before and after calculating the logarithm of the accumulated value ratio, thereby ensuring the accuracy of the calculation result of the integer part according to the calculation characteristics of the FPGA, and then subtracts a certain value C to eliminate the data change generated when the accumulated value ratio is expanded by A times, thereby completing the logarithm of the accumulated value ratio.

[0079] 4. In order to distinguish whether any moment in the original data is a noise signal, a fixed value is set to compare with the error reduction data, so that any moment is marked as having a pulse signal or not, and the pulse signal data corresponding to the moment without a pulse signal is discarded to achieve noise signal filtering.

[0080] 5. The present invention obtains the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value by calculating according to the A unit, and compares them with the B unit data, thereby completing the acquisition of the pulse mark of the radar pulse signal, and finally obtaining the pulse description word according to the pulse mark calculation, and finally obtaining the radar signal parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0082] Figure 1 It is a flow chart of the adaptive detection method of radar pulse signal of the present invention;

[0083] Figure 2 A waveform diagram of the original data of the radar pulse signal of the present invention;

[0084] Figure 3 A waveform diagram of the error reduction data of the present invention;

[0085] Figure 4 It is a waveform diagram of the A unit data and the B unit data of the present invention;

[0086] Figure 5 It is a graphical display of the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value source in vivado. DETAILED DESCRIPTION

[0087] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0088] Those skilled in the art can understand that all or part of the steps in the following embodiments can be completed by instructing the relevant hardware through a program, so the present application can be in the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application can be in the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0089] In order to solve the problem in the prior art that the threshold is difficult to be adaptively changed according to different environments, resulting in low detection accuracy of pulse signals, the present invention provides an adaptive detection method for radar pulse signals, such as Figure 1 As shown, the acquired radar pulse signal is processed in real time. The detection method includes the following steps:

[0090] S1. The original data containing the radar pulse signal is obtained through FPGA, and the original data is copied into two paths, one for backup data and the other for channelization processing to obtain pre-processed data. The waveform of the original data of the radar pulse signal is as follows: Figure 2 As shown;

[0091] S2, starting from the first data in the preprocessed data, select several continuous real numbers in turn, and set several corresponding angles to perform trigonometric function transformation on them to obtain IQ data; in order to improve the operation speed of the FPGA system when calculating the IQ data, in step S2, the following steps are specifically included:

[0092] S21, starting from the first real number in the preprocessed data, sequentially obtain a number of consecutive real numbers; the number of consecutive real numbers can be named in sequence: data0, data1, data2 and data3;

[0093] S22, setting a number of conversion angles corresponding to the same number of consecutive real numbers;

[0094] S23. Calculate a number of continuous real numbers in sequence according to the conversion angle, and arrange them in order to obtain IQ data; the expression of any IQ data is: ,in , in the above formula, are the pre-processed data before conversion, which are data0, data1, data2 and data3. For the conversion angle, the number of continuous real numbers and conversion angles are both 4, and the values ​​of the conversion angles corresponding to the 4 continuous real numbers are 0°, 90°, 180° and 270° respectively. For example, the 4 angles correspond to data0, data1, data2 and data3 respectively. The purpose of selecting this angle is to make and The result of the calculation is an integer, so that the result of the calculation and is an integer to facilitate the calculation of the FPGA system and improve the calculation speed. Within 0~360°, and There are only four integer values, so four consecutive real numbers are selected for processing and calculation each time. and are the real and imaginary parts of the IQ data respectively;

[0095] S3, sequentially calculating the amplitude absolute value of each data in the IQ data to obtain amplitude absolute value data, and sequentially calculating the amplitude mean of each of several data in the amplitude absolute value data to obtain amplitude mean data, and copying the amplitude mean data into A unit data and B unit data; in order to describe the calculation process of the amplitude mean data in detail, in step S3, the following steps are specifically included:

[0096] S31. Calculate the absolute value of the amplitude of each data in the IQ data to obtain the absolute value of the amplitude data. The original data of the radar pulse signal is acquired sequentially over time, so the absolute value of the amplitude data is also arranged sequentially in accordance with the inherent data rule form over time. The calculation formula of the absolute value of the amplitude is:

[0097] ;

[0098] in, Indicates the absolute value of the amplitude of a single IQ data. and Respectively represent the number with a larger absolute value and the number with a smaller absolute value of the real part and the imaginary part of a single IQ data;

[0099] S32, sequentially calculating the amplitude mean of each of the plurality of data in the amplitude absolute value data, and forming amplitude mean data in order; the calculation formula of the amplitude mean is:

[0100] ;

[0101] In the above formula, represents the mean amplitude, Indicates the number of selected continuous absolute value amplitude data. Represents the i-th data in the selected amplitude absolute value data, The best value is 32. After experimental verification, if If the value is 16, the collected data is too small, which sometimes causes a large error in the amplitude mean. If the value is 64, the FPGA's computing speed is relatively slow, resulting in a large computing load on the FPGA.

[0102] S33, the amplitude mean data is copied into A unit data and B unit data, and the waveform diagrams of A unit data and B unit data are as follows: Figure 4 shown.

[0103] S4, starting from the first data, the data cumulative value of each m consecutive data in the A unit data is calculated in sequence to obtain the data cumulative value data, and the data cumulative value data of the current clock is used as the dividend and divided by the data cumulative value at least m-1 clocks before in the FPGA to calculate the cumulative value ratio to obtain the cumulative value ratio data; the data cumulative value data and the cumulative value ratio data are respectively the data strings obtained in time sequence by the data cumulative value and the cumulative value ratio. In order to further illustrate the calculation method of the data cumulative value data and the cumulative value ratio data, in step S4, the following steps are specifically included:

[0104] S41, starting from the first data, sequentially calculate the data accumulation value of each m consecutive data in the A unit data; the calculation formula of the data accumulation value is:

[0105] ;

[0106] In the above formula, Indicates the data accumulation value of every m consecutive data in the A unit data. It represents the i-th data selected from the A unit data, which is the amplitude mean. The number of selected continuous data is indivual; The best value is 16. Experimental verification shows that calculating the accumulated value of every 16 consecutive data in the A unit data starting from the first data can ensure the operation speed of FPGA.

[0107] S42, sequentially determine whether the current data accumulation value of the A unit data is the mth clock and later in the FPGA;

[0108] If yes, proceed to step S43;

[0109] If not, the current data accumulation value is discarded;

[0110] S43, taking the current data accumulated value as the dividend and dividing it with the data accumulated value at least m-1 clocks before the current one in the FPGA to calculate the accumulated value ratio, and arranging them in order to obtain accumulated value ratio data; the calculation formula of the accumulated value ratio is:

[0111] ;

[0112] In the above formula, Indicates the ratio of cumulative values, is the accumulated value of the current clock, Indicates the accumulated value before a certain clock in the FPGA. The purpose of selecting the accumulated value of data at least m-1 clocks before the current as the divisor is to prevent the original data of the radar pulse signal from overlapping. When the overlapping range is larger, the value of the accumulated value ratio is closer to 1. Therefore, this method can make the change characteristics of the accumulated value ratio more significant.

[0113] S5, the accumulated value ratio data is sequentially multiplied, logarithmized, and subtracted to obtain error reduction data; if the accumulated value ratio data is directly logarithmized, the accumulated value ratio may be a decimal, which causes poor accuracy and speed of FPGA calculation, so it needs to be integerized first. In step S5, the following steps are specifically included:

[0114] S51, sequentially enlarging any data in the cumulative value ratio data by A times; the best value of A is 100, which can just convert the cumulative value ratio into an integer with the least amount of calculation;

[0115] S52, calculating the logarithm of the ratio of the accumulated values ​​after the expansion by A times; the calculation formula of the logarithm is:

[0116] ;

[0117] In the above formula, The logarithm of the ratio of the accumulated value after expanding by A times is calculated by taking the logarithm. is the expansion factor, The i-th data in the cumulative value ratio data after expanding by A times; the best value of B is 200, which is used to expand the decimals to facilitate calculation and ensure the calculation accuracy of the integer part;

[0118] S53, subtract C from the obtained logarithm to eliminate the value growth when expanding A times, and obtain the error reduction data; the value C needs to be calculated first, and its value is the difference between the result of calculating the logarithm of the cumulative value ratio after expanding A times and the result of directly calculating the logarithm of the cumulative value ratio. The waveform of the error reduction data is as follows: Figure 3 shown.

[0119] S6, set a fixed value, and calculate the difference between the error reduction data and the fixed value to mark the moment when the pulse signal exists, and determine the pulse mark containing the rising edge, the falling edge, and the pulse mark without the rising edge and the falling edge at the moment when the pulse signal exists according to the amplitude value of the B unit data and the rising edge amplitude comparison value and the falling edge amplitude comparison value; at this time, it is necessary to calculate the threshold value according to the data of the A unit data in the calculation process, that is, the rising edge amplitude comparison value and the falling edge amplitude, so as to compare the amplitude value of the B unit data with the threshold value to obtain the pulse mark containing the rising edge, the falling edge, and the pulse mark without the rising edge and the falling edge. In step S6, the following steps are specifically included:

[0120] S61, setting a fixed value; the fixed value is related to the application environment of the FPGA and its own circuit process and material parameters, etc., and needs to be measured first to remove the pulse signal of the environment and the product itself, so as to set the fixed value according to the pulse signal. In step S61, the following steps are specifically included:

[0121] S611, placing the FPGA in a real environment to be used without radar pulse signals;

[0122] S612, connecting the FPGA to a regulated power supply and measuring the amplitude of the pulse signal at any time in the real environment;

[0123] S613, calculating the absolute values ​​of the maximum and minimum values ​​of the pulse signal amplitude to obtain the amplitude range;

[0124] S614, the amplitude range is equally divided into a number of range steps, and the amplitude density of any pulse signal amplitude within the range step is calculated; the calculation formula of the amplitude density is:

[0125] ;

[0126] in,

[0127] ;

[0128] In the above formula, It represents the amplitude density of the i-th pulse signal within the extreme difference step. is the symbolic function, and are the i-th and j-th pulse signal amplitudes respectively, k represents the number of pulse signal amplitudes, represents the equal division coefficient, is the range of the pulse signal amplitude, That is the extreme step distance;

[0129] S615. Calculate the average value of the amplitudes of several pulse signals with the largest pulse density to obtain a fixed value. In this way, the amplitudes of some pulse signals with smaller pulse density can be filtered out, thereby filtering out the amplitudes of some pulse signals with abnormal values.

[0130] S62, determining in turn whether each error reduction data is greater than a fixed value;

[0131] If yes, the time corresponding to the error reduction data is marked as the presence of a pulse signal;

[0132] If not, the moment corresponding to the error reduction data is marked as no pulse signal, which means there is no pulse signal at this moment, and the pulse signal at this moment in the original signal is an environmental noise signal, which is filtered;

[0133] S63, calculating the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value according to the A unit data; in order to further illustrate the calculation method of the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value, and to improve the calculation accuracy of the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value, in step S63, the following steps are specifically included:

[0134] S631, obtaining the pulse amplitude high value and pulse amplitude low value of the A unit data;

[0135] S632, calculating the pulse amplitude middle value according to the pulse amplitude high value and the pulse amplitude low value; the calculation formula of the pulse amplitude middle value is:

[0136] ;

[0137] In the above formula, Indicates the middle value of the pulse amplitude, Indicates the high value of pulse amplitude, Indicates low value of pulse amplitude;

[0138] S633, calculate the pulse rising edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse rising edge amplitude comparison value is:

[0139] ;

[0140] In the above formula, Indicates the pulse rising edge amplitude comparison value, and They are high value coefficient and low value coefficient, and their values ​​are generally 0.75 and 0.25 respectively;

[0141] S634. Calculate the pulse falling edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse falling edge amplitude comparison value is:

[0142] ;

[0143] In the above formula, Indicates the pulse falling edge amplitude comparison value, is the falling edge coefficient, Generally it is 0.25.

[0144] S64, sequentially comparing the amplitude value of the B unit data that does not contain the no-pulse signal mark with the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value;

[0145] If the amplitude value is greater than or equal to the pulse rising edge amplitude comparison value, then the moment is marked as the pulse mark of the rising edge;

[0146] If the amplitude value is less than or equal to the pulse falling edge amplitude comparison value, then the moment is marked as the pulse mark of the falling edge;

[0147] If the amplitude value is between the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value, it is marked as a pulse mark without rising edge and falling edge, such as Figure 5 As shown, it is a graphical display of the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value source in vivado.

[0148] S7. The pulse descriptor is calculated through FPGA according to the pulse mark of the B unit data, and is fused and sorted with the backup data to obtain the radar signal parameters and output. The radar signal parameters mainly include pulse-to-pulse (five pulse descriptors: pulse width, arrival time, arrival angle, amplitude frequency) and intra-pulse (modulation type, frequency modulation bandwidth, etc.) parameters. The fusion and sorting method is implemented through FPGA. There are a large number of methods, which will not be repeated here. The measured radar signal parameters can be the parameters of one's own radar signal and the enemy radar signal, which is convenient for speed measurement, distance measurement, etc., and interference can be carried out in the confrontation direction, etc.

[0149] When the present invention is implemented, the original data is first divided into two paths, the pre-processed data therein is processed to obtain IQ data, and then the amplitude mean data is calculated according to the IQ data, and then the amplitude mean data is copied into A unit data and B unit data, and then the A unit data is calculated to obtain the rising edge amplitude comparison value, the falling edge amplitude comparison value and the moment when the pulse signal mark exists, and then the B unit data is compared with the rising edge amplitude comparison value and the falling edge amplitude comparison value to obtain the pulse mark, and the pulse description word is calculated according to the pulse mark, and finally it is fused and sorted with the backup data to obtain the radar signal parameters and output.

[0150] Corresponding to the adaptive detection method provided in the above-mentioned embodiment, the present embodiment also provides a system for implementing the adaptive detection method. Since the adaptive detection system provided in the present embodiment corresponds to the adaptive detection method provided in the above-mentioned embodiment, the implementation method of the aforementioned adaptive detection method is also applicable to the adaptive detection system provided in the present embodiment and will not be described in detail in the present embodiment.

[0151] The system comprises a processor and a memory, wherein the memory is used to store a computer program, and the computer program implements an adaptive detection method when executed by the processor.

[0152] The above implementation methods have been described in detail. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. An adaptive detection method for radar pulse signals, characterized in that: The detection method comprises the following steps: S1. Obtain the original data containing the radar pulse signal through FPGA, and copy the original data into two paths, one path is backup data, and the other path is channelized to obtain pre-processed data; S2. Starting from the first data in the preprocessed data, select a number of continuous real numbers in sequence, and set a number of corresponding angles to perform trigonometric function transformation on them to obtain IQ data; S3, calculating the absolute value of the amplitude of each data in the IQ data in turn, and calculating the amplitude mean of each number of data in the absolute value of the amplitude data in turn, and copying them into A unit data and B unit data; S4, starting from the first data, sequentially calculate the data accumulation value of each m consecutive data in the A unit data, and calculate the accumulation value ratio by dividing the data accumulation value of the current clock by the data accumulation value of at least m-1 clocks before in the FPGA; S5, performing multiple expansion, logarithm and subtraction operations on the accumulated value ratio data in sequence to obtain error reduction data; S6, setting a fixed value, and calculating the difference between the error reduction data and the fixed value to mark the moment when the pulse signal exists, and calculating the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value according to the A unit data, and determining the pulse mark at the moment when the pulse signal exists according to the amplitude value of the B unit data and the rising edge amplitude comparison value and the falling edge amplitude comparison value; S7. Calculate the pulse description word through FPGA according to the pulse mark of the B unit data, fuse and sort it with the backup data to obtain the radar signal parameters and output them.

2. The adaptive detection method according to claim 1, characterized in that: In step S2, the following steps are specifically included: S21, starting from the first real number in the preprocessed data, sequentially obtaining a number of consecutive real numbers; S22, setting a number of conversion angles corresponding to the same number of consecutive real numbers; S23. Calculate a number of continuous real numbers in sequence according to the conversion angle, and arrange them in order to obtain IQ data; the expression of any IQ data is: ,in , in the above formula, is the preprocessed data before transformation, To convert the angle.

3. The adaptive detection method according to claim 1, characterized in that: In step S3, the following steps are specifically included: S31, calculating the absolute value of the amplitude of each data in the IQ data to obtain the absolute value of the amplitude data; the calculation formula of the absolute value of the amplitude is: ； in, Indicates the absolute value of the amplitude of a single IQ data. and Respectively represent the numbers with larger absolute values ​​and smaller absolute values ​​of the real part and imaginary part of a single IQ data; S32, sequentially calculating the amplitude mean of each of the plurality of data in the amplitude absolute value data, and forming amplitude mean data in order; the calculation formula of the amplitude mean is: ； In the above formula, represents the mean amplitude, Indicates the number of selected continuous absolute value amplitude data. Represents the i-th data in the selected amplitude absolute value data; S33. Copy the amplitude mean data into A unit data and B unit data.

4. The adaptive detection method according to claim 1, characterized in that: In step S4, the following steps are specifically included: S41, starting from the first data, sequentially calculate the data accumulation value of each m consecutive data in the A unit data; the calculation formula of the data accumulation value is: ； In the above formula, Indicates the data accumulation value of every m consecutive data in the A unit data. It represents the i-th data selected from the A unit data, which is the amplitude mean. The number of selected continuous data is indivual; S42, sequentially determine whether the current data accumulation value of the A unit data is the mth clock and later in the FPGA; If yes, proceed to step S43; If not, the current data accumulation value is discarded; S43, taking the current data accumulated value as the dividend and dividing it with the data accumulated value at least m-1 clocks before the current one in the FPGA to calculate the accumulated value ratio, and arranging them in order to obtain accumulated value ratio data; the calculation formula of the accumulated value ratio is: ； In the above formula, Indicates the ratio of accumulated values, is the accumulated value of the current clock, Indicates the accumulated value in the FPGA before a certain clock.

5. The adaptive detection method according to claim 1, characterized in that: In step S5, the following steps are specifically included: S51, sequentially enlarging any data in the accumulated value ratio data by A times; S52, calculating the logarithm of the ratio of the accumulated values ​​after the expansion by A times; the calculation formula of the logarithm is: ； In the above formula, The logarithm of the ratio of the accumulated value after expanding by A times is calculated by taking the logarithm. is the expansion factor, is the i-th data in the cumulative value ratio data after being expanded A times; S53. Subtract C from the obtained logarithm to eliminate the numerical increase when it is enlarged by A times, and obtain error reduction data.

6. The adaptive detection method according to claim 1, characterized in that: In step S6, the following steps are specifically included: S61, setting a fixed value; S62, determining in turn whether each error reduction data is greater than a fixed value; If yes, the time corresponding to the error reduction data is marked as the presence of a pulse signal; If not, the time corresponding to the error reduction data is marked as no pulse signal; S63, calculating the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value according to the A unit data; S64, sequentially comparing the amplitude value of the B unit data that does not contain the no-pulse signal mark with the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value; If the amplitude value is greater than or equal to the pulse rising edge amplitude comparison value, then the moment is marked as the pulse mark of the rising edge; If the amplitude value is less than or equal to the pulse falling edge amplitude comparison value, then the moment is marked as the pulse mark of the falling edge; If the amplitude value is between the pulse rising edge amplitude comparison value and the pulse falling edge amplitude comparison value, it is marked as a pulse mark without rising edge and falling edge.

7. The adaptive detection method according to claim 6, characterized in that: In step S61, the following steps are specifically included: S611, placing the FPGA in a real environment to be used without radar pulse signals; S612, connecting the FPGA to a regulated power supply and measuring the amplitude of the pulse signal at any time in the real environment; S613, calculating the absolute values ​​of the maximum and minimum values ​​of the pulse signal amplitude to obtain the amplitude range; S614, the amplitude range is equally divided into a number of range steps, and the amplitude density of any pulse signal amplitude within the range step is calculated; the calculation formula of the amplitude density is: ； in, ； In the above formula, It represents the amplitude density of the i-th pulse signal within the extreme difference step. is the symbolic function, and are the i-th and j-th pulse signal amplitudes respectively, k represents the number of pulse signal amplitudes, represents the equal division coefficient, is the range of the pulse signal amplitude, That is the extreme step distance; S615, calculating the average value of the amplitudes of several pulse signals with the largest pulse density to obtain a fixed value.

8. The adaptive detection method according to claim 6, characterized in that: In step S63, the following steps are specifically included: S631, obtaining the pulse amplitude high value and pulse amplitude low value of the A unit data; S632, calculating the pulse amplitude middle value according to the pulse amplitude high value and the pulse amplitude low value; the calculation formula of the pulse amplitude middle value is: ； In the above formula, Indicates the middle value of the pulse amplitude, Indicates the high value of pulse amplitude, Indicates low value of pulse amplitude; S633, calculate the pulse rising edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse rising edge amplitude comparison value is: ； In the above formula, Indicates the pulse rising edge amplitude comparison value, and They are high value coefficient and low value coefficient respectively; S634. Calculate the pulse falling edge amplitude comparison value according to the pulse amplitude high value, the pulse amplitude low value and the pulse amplitude middle value; the calculation formula of the pulse falling edge amplitude comparison value is: ； In the above formula, Indicates the pulse falling edge amplitude comparison value, is the falling edge coefficient.

9. The adaptive detection method according to claim 2, characterized in that: In step S2, the number of the continuous real numbers and the conversion angles are both 4, and the values ​​of the conversion angles corresponding to the 4 continuous real numbers are 0°, 90°, 180° and 270° respectively.

10. A system for implementing the adaptive detection method according to any one of claims 1 to 9, characterized in that: The method comprises a processor and a memory, wherein the memory is used to store a computer program, and when the computer program is executed by the processor, the adaptive detection method according to any one of claims 1 to 9 is implemented.

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