A sequence correlation-based radar wave cell extraction method and system

Abstract

The application relates to the technical field of wave form unit extraction, and discloses a radar wave form unit extraction method and system based on sequence correlation, which comprises the following steps: performing sequence correlation on a pulse sequence group based on pulse width extraction; and confirming the pulse sequence group with successful correlation as a radar wave form unit. The application solves the problems of the prior art, such as low wave form extraction accuracy and poor adaptability of the radar wave form extraction algorithm.

Description

Technical Field

[0001] This invention relates to the field of waveform unit extraction technology, specifically a radar waveform unit extraction method and system based on sequence correlation. Background Technology

[0002] With the development of radar technology, multi-functional radars, represented by active phased array radars, are increasingly deployed in the battlefield electromagnetic environment. Multi-functional radars have diverse functions and complex waveforms, posing a great challenge to electronic reconnaissance. Waveform units are a basic component of multi-functional radars, and the quality of their extraction has an important impact on radiation source type identification and radiation source working mode discrimination. Liu Haijun (Liu Haijun, Fan Yun, Li Yue, et al. Research on radar word extraction technology in multi-functional radar modeling [J]. Journal of National University of Defense Technology, 2010, 32(2)) proposed a radar word extraction algorithm based on three-level matching, but this method requires prior knowledge of the waveform library, which is often difficult to implement in electronic countermeasures application scenarios. Ma Shuang (Ma Shuang, Liu Zheng, Jiang Wenli. Analysis method of multi-functional radar pulse train based on amplitude change point detection [J]. Acta Electronica Sinica, 2013, 41(7)) used amplitude changes to detect radar waveforms, but due to clutter, noise and interference in actual scenarios, the amplitude will be greatly distorted, resulting in inaccurate radar waveform extraction. Fang Yi (Fang Yi, Chen Qiuju, Pan Jifei, et al. Bayesian-based detection of change points in multi-functional radar pulse trains [J]. Journal of Command and Control, 2019, 5(4)) used a sliding window to divide waveform units, but lacked a basis for dividing the sliding window length. Fu Yuxin (Fu Yuxin, Huang Jie, Jiang Neng, et al. A method and system for extracting multi-functional radar waveform units based on a dot matrix model, application number: CN202210585348.6) extracted radar waveform units based on a dot matrix model, but due to the time-consuming image processing, it was difficult to meet the needs of real-time processing.

[0003] Traditional waveform element extraction methods mostly require prior acquisition of the radar's waveform element set, which is often difficult to meet in non-cooperative scenarios such as electronic warfare. Furthermore, radar waveform element extraction based on amplitude variation suffers from low accuracy due to amplitude distortion. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a radar waveform unit extraction method and system based on sequence correlation, which solves the problems of low waveform extraction accuracy and poor adaptability of radar waveform extraction algorithms in existing technologies.

[0005] The technical solution adopted by the present invention to solve the above problems is:

[0006] A radar waveform unit extraction method based on sequence correlation is proposed, which performs sequence correlation on pulse sequence groups extracted based on pulse width, and identifies the successfully correlated pulse sequence groups as radar waveform units.

[0007] As a preferred technical solution, the steps include:

[0008] S1, Pulse Width Clustering: Clustering pulse widths; Let the pulse sequence be X={x1,x2,…,x…} i ,…,x M}, where M is the number of pulses in the pulse sequence X, x i Let x represent the i-th pulse in the pulse sequence. i Represented as Equation (1):

[0009] x i ={rf i ,toa i ,pw i ,pa i}; (1)

[0010] In equation (1), rf i toa i rtoa i ,pw i and pa i pulse x i Frequency, absolute arrival time, pulse width, amplitude;

[0011] S2, Pulse Sequence Group Extraction: Extract pulse sequence groups from pulses after pulse width clustering;

[0012] S3, Pulse Sequence Group Correlation: Perform sequence correlation processing on the pulse sequence group to match the input pulse sequence with the library pulse sequence;

[0013] S4, Matching Decision: Determines whether the pulse sequence group is successfully matched;

[0014] S5, Pulse Sequence Group Library Update: Update the library pulse sequence group UpdateLibSeqDat based on the number of shift pulses of the input pulse sequence and the library pulse sequence;

[0015] S6, Waveform Unit Extraction: Extract waveform units from the updated pulse sequence group library.

[0016] As a preferred technical solution, step S1 includes the following steps:

[0017] S11, input pulses one by one;

[0018] S12, determine whether the pulse traversal is complete: if yes, proceed to step S13; if no, end the clustering of pulse widths.

[0019] S13, Traverse the current pulse width groups;

[0020] S14. Determine if there is a successfully matched pulse width group: if yes, update the pulse width group center value and then end the pulse width clustering; if no, create a new pulse width group, assign the pulse width value to the pulse width group center value, and then end the pulse width clustering.

[0021] As a preferred technical solution, the specific method for determining whether a successfully matched pulse width group exists in step S14 is as follows:

[0022] pulse x i pw i With the center value pwgrpval of the j-th pulse width group j Comparing the results, if equation (2) is satisfied:

[0023] |pw i -pwgrpval j |≤Gate pwgrp (2);

[0024] Among them, Gate pwgrp This indicates the set comparison threshold;

[0025] Then it is assumed that pulse x i pw i Successfully matched with the j-th pulse width group.

[0026] As a preferred technical solution, step S2 includes the following steps:

[0027] S21, Determine whether the repetition frequency calculation is complete: if yes, end the pulse sequence group extraction; if no, proceed to step S22.

[0028] S22, Calculate the repetition frequency Pri of each pair of adjacent pulses k ;

[0029] S23, Determine Pri k Is it within the effective repetition frequency range [MinValidPRI, MaxValidPRI] and the number of pulses ≥ NumGateSeqGrp? If yes, proceed to step S24; otherwise, end the pulse sequence group extraction. Wherein, MinValidPRI represents the lower limit of the effective repetition frequency, MaxValidPRI represents the upper limit of the effective repetition frequency, and NumGateSeqGrp represents the threshold for the number of pulses in the pulse sequence group.

[0030] S24, create a new pulse width group, assign the pulse width value to the center value of the pulse width group, and then end the pulse sequence group extraction.

[0031] As a preferred technical solution, in step S23, MinValidPRI is set to 300us and MaxValidPRI is set to 7000us.

[0032] As a preferred technical solution, step S3 includes the following steps:

[0033] S31, Let the input pulse sequence group be...

[0034] InSeqDat0={SigSeq 0_1 ,SigSeq 0_2 ,…,SigSeq 0_M The pulse sequence group to be matched is:

[0035] LibSeqDat0={LibSeq 0_1 LibSeq 0_2 ,…,LibSeq 0_N},but:

[0036] SigSeq 0_1 ={rf sig0_1 toa sig0_1 ,rtoa sig0_1 ,pw sig0_1}; (3)

[0037] In equation (3), SigSeq 0_1 ,SigSeq 0_2 ,…,SigSeq 0_M These are the 1st, 2nd, ..., ...th elements in InSeqDat0. M 1 element, LibSeq 0_1 LibSeq 0_2 ,…,LibSeq 0_N These are the 1st, 2nd, ..., ...th elements in LibSeqDat0. N 1 element, rf sig0_1 ,pw sig0_1 toa sig0_1 rtoa sig0_1 These represent the input sequence frequency, pulse width, arrival time, and relative arrival time, respectively, and rtoa. sig0_M =toa sig0_M -toa sig0_1 ;

[0038] LibSeq 0_1 ={rf lib0_1 toa lib0_1 ,rtoa lib0_1 ,pw lib0_1}; (4)

[0039] In equation (4), rf lib0_1 ,pw lib0_1 toa lib0_1 rtoa lib0_1 These represent the library sequence frequency, pulse width, arrival time, and relative arrival time, respectively, rtoa lib0_N =toa lib0_N -toa lib0_1 ;

[0040] The condition for matching pulse sequence groups is relative arrival time matching, and the matching condition for relative arrival time is Equation (5);

[0041] |rtoa sig0_i -rtoa lib0_j |≤rtoa gate (5)

[0042] In equation (5), rtoa gate Matching thresholds to relative arrival times;

[0043] S32, shift the input pulse sequence group i pulses and the library pulse sequence group j pulses respectively to obtain the shifted input sequence InSeqDat i ={SigSeq i_1 ,SigSeq i_2 ,…,SigSeq i_M} and library sequence LibSeqDat j ={LibSeq j_1 LibSeq j_2 ,…,LibSeq j_N}, calculate the number of matching pulses that satisfy equation (5), if the number of successfully matched pulses is K ij ,but:

[0044] MatchNum = max(K) ij ); i=1,2,…,M, j=1,2,…,N (6);

[0045] In equation (5), SigSeq i_1 ,SigSeq i_2 ,…,SigSeq i_M They are InSeqDat i The 1st, 2nd, ..., M 1 element, LibSeq j_1 LibSeq j_2 ,…,LibSeq j_N They are LibSeqDat j The 1st, 2nd, ..., NThere are 1 element, MatchNum, which is the maximum number of matched pulses obtained after moving the input pulse sequence group and the library pulse sequence group.

[0046] As a preferred technical solution, step S4 includes the following steps:

[0047] S41, calculate the matching ratio between the input pulse sequence and the library pulse sequence according to equation (7);

[0048] SeqMatRatio=MatchNum / min(SigSeqNum,LibSeqNum); (7)

[0049] S42, according to equation (8), determine whether the sequence matching ratio SeqMatRatio meets the matching threshold Gate. SeqMatRatio If the conditions are met, the sequence is considered to be successfully matched, and the process proceeds to step S5; otherwise, the matching is considered to have failed.

[0050] SeqMatRatio≥Gate SeqMatRatio (8).

[0051] As a preferred technical solution, in step S6, the condition for the radar waveform unit is that the number of pulses in the pulse sequence group is ≥ NumGate. WaveUnit Among them, NumGate WaveUnit This is the threshold for the number of pulses in the waveform unit.

[0052] A radar waveform element extraction system based on sequence correlation, used to implement the radar waveform element extraction method based on sequence correlation, includes the following modules connected in sequence:

[0053] Pulse width clustering module: Used to cluster pulse widths; let the pulse sequence be X={x1,x2,…,x…} i ,…,x M}, where M is the number of pulses in the pulse sequence X, x i Let x represent the i-th pulse in the pulse sequence. i Represented as Equation (1):

[0054] x i ={rf i ,toa i ,pw i ,pa i}; (1)

[0055] In equation (1), rf i toa i rtoa i ,pw i and pa i pulse xi Frequency, absolute arrival time, pulse width, amplitude;

[0056] Pulse sequence group extraction module: Used to extract pulse sequence groups from pulses after pulse width clustering;

[0057] Pulse sequence group correlation module: used to perform sequence correlation processing on pulse sequence groups, matching the input pulse sequence with the library pulse sequences;

[0058] Matching and judging module: used to determine whether the pulse sequence group is successfully matched;

[0059] Pulse sequence group library update module: used to update the library pulse sequence group UpdateLibSeqDat according to the number of shift pulses of the input pulse sequence and the library pulse sequence;

[0060] Waveform unit extraction module: Used to extract waveform units from the updated pulse sequence group library.

[0061] Compared with the prior art, the present invention has the following advantages:

[0062] (1) Based on in-depth analysis of multi-functional radar objects, this invention first performs pulse width clustering, then extracts and correlates pulse sequence groups, and finally extracts waveform units from the successfully correlated pulse sequence groups.

[0063] (2) This invention can accurately extract the radar waveform unit without prior acquisition of the radar waveform unit, and the extraction effect is not affected by amplitude distortion. It can improve the adaptability of the radar waveform extraction algorithm, thereby enhancing the electronic warfare system's ability to identify and perceive multi-functional radar. Attached Figure Description

[0064] Figure 1 This is a flowchart of a radar waveform unit extraction method based on sequence correlation according to the present invention;

[0065] Figure 2 This is a flowchart of pulse width clustering.

[0066] Figure 3 Flowchart for extracting pulse sequence groups;

[0067] Figure 4 To update the pulse sequence group flowchart;

[0068] Figure 5 The result image is extracted from the radar waveform unit. Detailed Implementation

[0069] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0070] Example 1

[0071] like Figures 1 to 5 As shown, based on an in-depth analysis of the multifunctional radar object, the present invention first performs pulse width clustering, then extracts and correlates pulse sequence groups, and finally extracts waveform units from the successfully correlated pulse sequence groups.

[0072] This invention can accurately extract radar waveform units without prior acquisition of radar waveform units, and the extraction effect is not affected by amplitude distortion. It can improve the adaptability of radar waveform extraction algorithms, thereby enhancing the electronic warfare system's ability to identify and perceive multi-functional radars.

[0073] This invention proposes a multifunctional radar waveform extraction method based on sequence correlation.

[0074] Because the repetition frequency sequence changes of the same radar waveform unit have good repeatability, and the pulse width value of a waveform unit generally does not change, this invention first clusters the pulse widths and extracts pulse sequence groups based on the effective waveform unit repetition frequency range. Then, it performs sequence correlation processing on the pulse sequence groups and finally confirms the successfully correlated pulse sequence groups as radar waveform units.

[0075] The processing flow of the radar waveform element extraction method based on sequence correlation is shown in the figure, and its detailed implementation steps are as follows:

[0076] Step 1: Pulse width clustering:

[0077] Let the pulse sequence be X = {x1, x2, ..., x...} M}, where M is the number of pulses in the pulse sequence X, and x is the number of pulses in the sequence. i It can be expressed as equation (1).

[0078] x i ={rf i ,toa i ,pw i ,pa i}; (1)

[0079] In equation (1), rf i toa i rtoa i ,pw i and pa i pulse x i The frequency, absolute arrival time, pulse width, and amplitude are used to extract the pulse width value pw for each pulse. i The detailed implementation steps of pulse width clustering are as follows:

[0080] 1) Obtain the current pulse width value, and set the i-th pulse width value pwi With the center value pwgrpval of the j-th pulse width group j Compare the current pulse width value with the pulse width group center value to determine whether they satisfy equation (2).

[0081] |pw i -pwgrpval j |≤Gate pwgrp (2)

[0082] If the condition is met, the i-th pulse width value is considered to be successfully matched with the j-th pulse width group, and the pulse width center value is updated; otherwise, proceed to step 2.

[0083] 2) Create a new pulse width group and assign the pulse width value to the center value of the pulse width group.

[0084] Step 2: Pulse sequence group extraction:

[0085] The repetition rate value for each pulse width group is calculated. If Pri k exist

[0086] Within the range of [MinValidPRI, MaxValidPRI], and with a pulse count greater than or equal to NumGate. SeqGrp If the result is positive, it is considered to be within a pulse sequence group; otherwise, a new pulse sequence group is created. Based on the working principle of multi-function radar, MinValidPRI is typically set to 300µs, and MaxValidPRI is typically set to 7000µs.

[0087] Step 3: Pulse sequence group correlation:

[0088] 1) Let the input pulse sequence be...

[0089] InSeqDat0={SigSeq 0_1 ,SigSeq 0_2 ,…,SigSeq 0_M The pulse sequence group to be matched is:

[0090] LibSeqDat0={LibSeq 0_1 LibSeq 0_2 ,…,LibSeq 0_N}

[0091] SigSeq 0_1 ={rf sig0_1 toa sig0_1 ,rtoa sig0_1 ,…,pw sig0_1}; (3)

[0092] In equation (3), rf sig0_1,pw sig0_1 toa sig0_1 rtoa sig0_1 These represent the input sequence frequency, pulse width, arrival time, and relative arrival time, respectively, and rtoa sig0_M =toa sig0_M -toa sig0_1 .

[0093] LibSeq 0_1 ={rf lib0_1 toa lib0_1 ,rtoa lib0_1 ,…,pw lib0_1}; (4)

[0094] In equation (4), rf lib0_1 ,pw lib0_1 toa lib0_1 rtoa lib0_1 These represent the library sequence frequency, pulse width, arrival time, and relative arrival time, respectively, rtoa lib0_N =toa lib0_N -toa lib0_1 The condition for matching pulse sequence groups is relative arrival time matching, and the matching condition for relative arrival time is Equation (5).

[0095] |rtoa sig0_i -rtoa lib0_j |≤rtoa gate (5)

[0096] In equation (5), rtoa gate A threshold is set for relative arrival time.

[0097] 2) Shift the input pulse sequence group i pulses and the library pulse sequence group j pulses respectively to obtain the shifted input sequence.

[0098] InSeqDat i ={SigSeq i_1 ,SigSeq i_2 ,…,SigSeq i_M}

[0099] and library sequence LibSeqDat j ={LibSeq j_ 1,LibSeq j_ 2,…,LibSeq j_N}, calculate the number of matching pulses that satisfy equation (5), if the number of successfully matched pulses is K ij The diagram shown is a schematic of sequence shifting.

[0100] MatchNum = max(K)ij ); i=1,2,…,M, j=1,2,…,N (6)

[0101] Step 4: Determine if the pulse sequence group matches successfully:

[0102] The matching ratio between the input pulse sequence and the library pulse sequence is calculated according to equation (7).

[0103] SeqMatRatio=MatchNum / min(SigSeqNum,LibSeqNum); (7)

[0104] Based on equation (8), determine whether the sequence matching ratio SeqMatRatio meets the sequence matching ratio threshold Gate. SeqMatRatio If the conditions are met, the sequence is considered to be successfully matched, and the process proceeds to step five; otherwise, the matching is considered to have failed.

[0105] SeqMatRatio≥Gate SeqMatRatio (8)

[0106] Step 5: Pulse sequence library update:

[0107] The library pulse sequence group UpdateLibSeqDat is updated based on the number of shift pulses in both the input pulse sequence and the library pulse sequence. (See diagram below.) Figure 4 .

[0108] Step 6: Waveform Unit Extraction

[0109] Waveform units are extracted from the updated pulse sequence group library. The condition for extracting radar waveform units is that the number of pulses in the pulse sequence group is greater than or equal to the waveform unit pulse number threshold NumGate. WaveUnit .

[0110] The present invention has the following effects:

[0111] The proposed radar waveform element extraction method based on sequence correlation first clusters the pulse widths of identical radar waveform elements, assuming that the pulse widths remain essentially constant. Then, it extracts pulse sequence groups based on pulse repetition frequency and pulse count. Next, it correlates these pulse sequence groups and finally extracts the waveform elements from the successfully correlated pulse sequence groups. Simulation data shows that this method can accurately extract waveform elements from multi-functional radars.

[0112] Example 2

[0113] like Figures 1 to 5 As shown, as a further optimization of Embodiment 1, this embodiment also includes the following technical features based on Embodiment 1:

[0114] To verify the effectiveness of this method, a multi-functional radar simulation signal was used for validation. The simulation parameters are shown in Table 1. Figure 5 As shown, four waveform parameters were extracted, with the waveform pulses identified by four different colors. The black box indicates the frequency, repetition rate, and pulse width of waveform units 1 to 4, and these parameters are consistent with the simulated signal parameters. This demonstrates that this method can accurately extract radar waveform units.

[0115] Table 1 Simulation Parameters

[0116]

[0117] As described above, the present invention can be implemented well.

[0118] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.

[0119] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Based on the technical essence of the present invention, any simple modifications, equivalent substitutions, and improvements made to the above embodiments within the spirit and principles of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for extracting radar waveform elements based on sequence correlation, characterized in that, Sequence correlation is performed on pulse sequence groups based on pulse width extraction, and the successfully correlated pulse sequence groups are identified as radar waveform units. This includes the following steps: S1, Pulse Width Clustering: Clustering pulse widths; Let the pulse sequence be... X ={ x 1, x 2,…, x i ,…, x M }, M pulse sequence X The number of pulses, x i Represents the first pulse in the pulse sequence i One pulse, x i Represented as Equation (1): x i ={ rf i , toa i , pw i, pa i}；(1) In formula (1) rf i , toa i , pw i and pa i pulses x i Frequency, absolute arrival time, pulse width, amplitude; S2, Pulse Sequence Group Extraction: Extract pulse sequence groups from pulses after pulse width clustering; S3, Pulse Sequence Group Correlation: Perform sequence correlation processing on the pulse sequence group to match the input pulse sequence with the library pulse sequence; S4, Matching Decision: Determines whether the pulse sequence group is successfully matched; S5, Pulse Sequence Group Library Update: Update the library pulse sequence group UpdateLibSeqDat based on the number of shift pulses of the input pulse sequence and the library pulse sequence; S6, Waveform Unit Extraction: Extract waveform units from the updated pulse sequence group library; Step S3 includes the following steps: S31, Let the input pulse sequence group be... InSeqDat 0={ SigSeq 0_1 , SigSeq 0_2 ,…, SigSeq 0_M The pulse sequence group to be matched is: LibSeqDat 0={ LibSeq 0_1 , LibSeq 0_2 ,…, LibSeq 0_N },but: SigSeq 0_1 ={ rf sig0_1 ， toa sig0_1 , rtoa sig0_1 , pw sig0_1}；(3) In equation (3), SigSeq 0_1 , SigSeq 0_2 ,…, SigSeq 0_M They are respectively InSeqDat The 1st, 2nd, ..., in 0 M One element, LibSeq 0_1 , LibSeq 0_2 ,…, LibSeq 0_N They are respectively LibSeqDat The 1st, 2nd, ..., in 0 N One element, rf sig0_1 , pw sig0_1 , toa sig0_1 , rtoa sig0_1 These are the input sequence frequency, pulse width, arrival time, and relative arrival time, respectively. rtoa sig0_M = toa sig0_M - toa sig0_1 ; LibSeq 0_1={ rf lib0_1 ， toa lib0_1 , rtoa lib0_1 , pw lib0_1}；(4) In equation (4), rf lib0_1 , pw lib0_1 , toa lib0_1 , rtoa lib0_1 These are the library sequence frequency, pulse width, arrival time, and relative arrival time, respectively. rtoa lib0_N = toa lib0_N - toa lib0_1 ; The condition for matching pulse sequence groups is relative arrival time matching, and the matching condition for relative arrival time is Equation (5); | rtoa sig0_i - rtoa lib0_j |≤ rtoa gate (5) In equation (5), rtoa gate Matching thresholds to relative arrival times; S32, move the input pulse sequence groups respectively i pulse and reservoir pulse sequence groups j A shift input sequence is obtained from one pulse. InSeqDat i ={ SigSeq i_1 , SigSeq i_2 ,…, SigSeq i_M } and library sequence LibSeqDat j ={ LibSeq j_1 , LibSeq j_2 ,…, LibSeq j_N }, calculate the number of matching pulses that satisfy equation (5), if the number of successfully matched pulses is K ij ,but: MatchNum= max ( K ij ); i =1,2,…, M , j =1,2,…, N (6); In equation (5), SigSeq i_1 , SigSeq i_2 ,…, SigSeq i_M They are respectively InSeqDat i The 1st, 2nd, ..., M One element, LibSeq j_1 , LibSeq j_2 ,…, LibSeq j_N They are respectively LibSeqDat j The 1st, 2nd, ..., N There are 1 element, MatchNum, which is the maximum number of matched pulses obtained after moving the input pulse sequence group and the library pulse sequence group.

2. The radar waveform unit extraction method based on sequence correlation according to claim 1, characterized in that, Step S1 includes the following steps: S11, input pulses one by one; S12, determine whether the pulse traversal is complete: if yes, proceed to step S13; if no, end the clustering of pulse widths. S13, Traverse the current pulse width groups; S14. Determine if there is a successfully matched pulse width group: if yes, update the pulse width group center value and then end the pulse width clustering; if no, create a new pulse width group, assign the pulse width value to the pulse width group center value, and then end the pulse width clustering.

3. The radar waveform unit extraction method based on sequence correlation according to claim 2, characterized in that, In step S14, the specific method for determining whether a successfully matched pulse width group exists is as follows: pulse x i of pw i With the j Central value of pulse width group pwgrpval j Comparing the results, if equation (2) is satisfied: (2)； in, This indicates the set comparison threshold; Then it is considered a pulse x i of pw i With the j Pulse width grouping and matching successful.

4. The radar waveform unit extraction method based on sequence correlation according to claim 1, characterized in that, Step S2 includes the following steps: S21, Determine whether the repetition frequency calculation is complete: if yes, end the pulse sequence group extraction; if no, proceed to step S22. S22, Calculate the repetition rate of each pair of adjacent pulses. Pri k ; S23, Judgment Pri k Is it within the effective repetition frequency range [MinValidPRI, MaxValidPRI] and the number of pulses ≥ NumGateSeqGrp? If yes, proceed to step S24; otherwise, end the pulse sequence group extraction. Wherein, MinValidPRI represents the lower limit of the effective repetition frequency, MaxValidPRI represents the upper limit of the effective repetition frequency, and NumGateSeqGrp represents the threshold for the number of pulses in the pulse sequence group. S24, create a new pulse width group, assign the pulse width value to the center value of the pulse width group, and then end the pulse sequence group extraction.

5. The radar waveform unit extraction method based on sequence correlation according to claim 4, characterized in that, In step S23, MinValidPRI is set to 300us and MaxValidPRI is set to 7000us.

6. The radar waveform unit extraction method based on sequence correlation according to claim 1, characterized in that, Step S4 includes the following steps: S41, calculate the matching ratio between the input pulse sequence and the library pulse sequence according to equation (7); SeqMatRatio=MatchNum / min(SigSeqNum,LibSeqNum); (7) S42, according to equation (8), determine whether the sequence matching ratio SeqMatRatio meets the matching threshold Gate. SeqMatRatio If the conditions are met, the sequence is considered to be successfully matched, and the process proceeds to step S5; otherwise, the matching is considered to have failed. SeqMatRatio≥Gate SeqMatRatio (8)。 7. A radar waveform unit extraction method based on sequence correlation according to any one of claims 1 to 6, characterized in that, In step S6, the condition for the radar waveform unit is that the number of pulses in the pulse sequence group is ≥ NumGate. WaveUnit Among them, NumGate WaveUnit This is the threshold for the number of pulses in the waveform unit.

8. A radar waveform unit extraction system based on sequence correlation, characterized in that, A radar waveform element extraction method based on sequence correlation as described in any one of claims 1 to 7 comprises the following modules connected in sequence: Pulse width clustering module: used to cluster pulse widths; assuming the pulse sequence is... X ={ x 1, x 2,…, x i ,…, x M }, M pulse sequence X The number of pulses, x i Represents the first pulse in the pulse sequence i One pulse, x i Represented as Equation (1): x i ={ rf i , toa i , pw i, pa i}； (1) In formula (1) rf i , toa i , pw i and pa i pulses x i Frequency, absolute arrival time, pulse width, amplitude; Pulse sequence group extraction module: Used to extract pulse sequence groups from pulses after pulse width clustering; Pulse sequence group correlation module: used to perform sequence correlation processing on pulse sequence groups, matching the input pulse sequence with the library pulse sequences; Matching and judging module: used to determine whether the pulse sequence group is successfully matched; Pulse sequence group library update module: used to update the library pulse sequence group UpdateLibSeqDat according to the number of shift pulses of the input pulse sequence and the library pulse sequence; Waveform unit extraction module: Used to extract waveform units from the updated pulse sequence group library.

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