In-pulse and inter-pulse combined anti-interference method based on clustering processing

Abstract

The embodiment of the invention relates to an intra-pulse and inter-pulse combined anti-interference method based on clustering processing, and the method comprises the steps: carrying out the intra-pulse interference judgment based on a first target clustering result and a first interference signal clustering result, which are obtained through the second-order clustering processing of a sum path orthogonal baseband signal, and carrying out the intra-pulse interference elimination processing; calculating a sum path noise mean value sequence and an auxiliary branch noise mean value sequence, and executing intra-pulse discontinuous interference judgment; utilizing the sidelobe cancellation sample data to calculate a sidelobe cancellation weight, and utilizing the sidelobe cancellation weight to perform sidelobe cancellation processing on the sum path orthogonal baseband signal after the intra-pulse interference elimination processing; and performing second-order clustering processing on the sum path orthogonal baseband signal after side lobe cancellation processing, performing inter-pulse interference judgment based on a second target clustering result and a second interference signal clustering result obtained by the second-order clustering processing, and performing inter-pulse interference elimination processing. According to the embodiment of the invention, the adaptive capacity to discontinuous noise interference is relatively high, and a relatively good anti-interference effect can be achieved.

Description

Technical Field

[0001] The present disclosure relates to the field of radar countermeasure technology, and in particular to an intra-pulse and inter-pulse joint anti-interference method based on clustering processing. Background Art

[0002] With the continuous development of jamming theory and jammer technology, the electromagnetic environment faced by radar has become more complex, and radar anti-jamming has become an important part of modern electronic warfare. Among them, in some typical combat environments such as missile-borne jamming, in order to achieve intra-pulse jamming of ground radars, intermittent noise jamming is widely used as a typical digital frequency storage and forwarding jammer in missile-borne active jammers. Strong jamming signals can suppress real target signals, making it impossible for ground radars to stably track targets and achieve the purpose of RF stealth, which brings certain difficulties to radar detection.

[0003] The existing methods for counteracting intermittent noise interference generally use waveform agility or frequency agility, but this method can neither counteract the main-sidelobe composite intermittent noise interference, nor has the ability to adapt to intermittent noise interference. It cannot achieve a good countermeasure effect when the interference intermittent period and duty cycle vary in a large range.

[0004] Therefore, it is necessary to provide a new technical solution to improve one or more problems existing in the above solutions.

[0005] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0006] The purpose of the embodiments of the present disclosure is to provide a joint intra-pulse and inter-pulse anti-interference method based on clustering processing, so as to enhance the adaptability to intermittent noise interference and achieve better countermeasure effect when the interference intermittent period and duty cycle vary in a relatively large range.

[0007] According to an embodiment of the present disclosure, a method for joint intra-pulse and inter-pulse anti-interference based on clustering processing is provided, comprising:

[0008] Acquire the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal, and perform second-order clustering processing on the sum-branch orthogonal baseband signal to obtain a first target clustering result and a first interference signal clustering result;

[0009] Performing intra-pulse interference judgment based on the first target clustering result and the first interference signal clustering result, and performing intra-pulse interference elimination processing on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference;

[0010] Based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, calculate the sum-path noise mean sequence and the auxiliary branch noise mean sequence, and perform intra-pulse intermittent interference judgment;

[0011] Comparing multiple noise means in the auxiliary branch noise mean sequence, obtaining cancellation sample position information, and obtaining sidelobe cancellation sample data according to the cancellation sample position information;

[0012] Calculating a sidelobe cancellation weight using the sidelobe cancellation sample data, and performing sidelobe cancellation processing on the sum-path orthogonal baseband signal after the intra-pulse interference elimination processing using the sidelobe cancellation weight;

[0013] Performing second-order clustering processing on the sum-path orthogonal baseband signal after the sidelobe cancellation processing to obtain a second target clustering result and a second interference signal clustering result;

[0014] An inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and an inter-pulse interference elimination process is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation process according to the inter-pulse interference judgment result.

[0015] In an exemplary embodiment of the present disclosure, the intra-pulse interference judgment is performed based on the first target clustering result and the first interference signal clustering result, and the intra-pulse interference elimination processing is performed on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference, including:

[0016] Extracting a first signal vector of the first target clustering result and a second signal vector of the first interference signal clustering result;

[0017] Performing mean processing on the first signal vector and the second signal vector to obtain a first mean and a second mean;

[0018] Performing ratio processing on the first mean value and the second mean value to obtain a first signal fluctuation factor;

[0019] Intra-pulse interference judgment is performed according to the first signal fluctuation factor, and intra-pulse interference is eliminated for the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference.

[0020] In an exemplary embodiment of the present disclosure, the intra-pulse interference judgment is performed according to the first signal fluctuation factor, and the intra-pulse interference is eliminated for the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference, including:

[0021] Comparing the first signal fluctuation factor with a first preset threshold;

[0022] If the first signal fluctuation factor is greater than the first preset threshold, there is intra-pulse interference between the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal;

[0023] In the presence of intra-pulse interference, the second mean value is used as the first interference removal threshold, and based on the first interference removal threshold, interference zeroing processing is performed on the sum-path orthogonal baseband signal using formula (1):

[0024]

[0025] Among them, A1 Σij A1 represents the sum of the orthogonal baseband signals after interference zeroing. ij Represents the pulses of the orthogonal baseband signal, avgidx2 i represents the first interference rejection threshold;

[0026] Based on the first interference rejection threshold, interference zeroing processing is performed on the auxiliary branch orthogonal baseband signal using formula (2):

[0027]

[0028] Among them, AF1 ij It represents the auxiliary branch orthogonal baseband signal after interference nulling processing, AF ij Represents the pulses of the auxiliary branch quadrature baseband signal, avgidx2 i Represents the first interference rejection threshold.

[0029] In an exemplary embodiment of the present disclosure, based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, the sum-path noise mean sequence and the auxiliary branch noise mean sequence are calculated, and the intra-pulse intermittent interference judgment is performed, including:

[0030] Performing pulse compression processing on the sum path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination processing to obtain sum path pulse compression data and auxiliary branch pulse compression data;

[0031] Calculating a summing path noise mean sequence and an auxiliary branch noise mean sequence using the summing path pulse compression data and the auxiliary branch pulse compression data;

[0032] The side lobe interference judgment is performed by formula (3):

[0033] (N Fi >ceoff2*N Σi )&&(N Fi >ceoff3*N FR )(3)

[0034] Among them, N Fi represents the noise mean of the ith pulse of the auxiliary branch, N Σi represents the noise mean of the ith pulse of the sum path, N FR represents the theoretical noise level of the auxiliary branch, ceoff2 represents the first noise level coefficient, and ceoff3 represents the second noise level coefficient;

[0035] When sidelobe interference exists, a low noise threshold and a high noise threshold of the auxiliary branch are calculated according to the auxiliary branch noise mean sequence, and intra-pulse intermittent interference judgment is performed based on the high noise threshold and the low noise threshold.

[0036] In an exemplary embodiment of the present disclosure, the calculating of the low noise threshold and the high noise threshold of the auxiliary branch according to the auxiliary branch noise mean sequence, and performing intra-pulse intermittent interference judgment based on the high noise threshold and the low noise threshold, includes:

[0037] The auxiliary branch noise mean sequence is averaged to obtain a noise threshold;

[0038] Based on the noise threshold, the auxiliary branch noise mean value sequence is subjected to threshold processing to obtain a low noise level mean value sequence and a high noise level mean value sequence;

[0039] The low noise level average value sequence is averaged to obtain the low noise threshold, and the high noise level average value sequence is averaged to obtain the high noise threshold, wherein any noise level average value in the low noise level average value sequence is less than any noise level average value in the high noise level average value sequence;

[0040] The intermittent interference judgment within the pulse is performed by formula (4):

[0041]

[0042] in, Indicates the high noise threshold, represents the low noise threshold, ceoff4 represents the third noise level coefficient, and if formula (4) is satisfied, there is sidelobe intermittent noise interference.

[0043] In an exemplary embodiment of the present disclosure, the step of performing comparison processing on a plurality of noise means in the auxiliary branch noise mean sequence to obtain cancellation sample position information includes:

[0044] Comparing multiple noise mean values ​​in the auxiliary branch noise mean value sequence to determine the maximum noise level average value;

[0045] The position information of the maximum noise level average value is recorded and used as the cancellation sample position information.

[0046] In an exemplary embodiment of the present disclosure, the acquiring of sidelobe cancellation sample data according to the cancellation sample position information further includes:

[0047] Selecting the auxiliary branch pulse compression data and the sum branch pulse compression data according to the cancellation sample position information;

[0048] Screening the selected auxiliary branch pulse compression data to obtain sidelobe cancellation sample data of the auxiliary branch, and obtaining a position matrix of the sidelobe cancellation sample data of the auxiliary branch;

[0049] Constructing the delay node data of the auxiliary branch based on the auxiliary branch pulse compression data, and selecting the delay node data of the auxiliary branch according to the position matrix to obtain the sidelobe cancellation delay node sample data of the auxiliary branch;

[0050] The sidelobe cancellation sample data includes the sidelobe cancellation sample data of the auxiliary branch and the sidelobe cancellation delay section sample data of the auxiliary branch.

[0051] In an exemplary embodiment of the present disclosure, in the step of screening the selected auxiliary branch pulse compression data to obtain the sidelobe cancellation sample data of the auxiliary branch, the screening process is performed using formula (5):

[0052] B FPosl >Nos rec &&B FPosl >B ΣPosl (5)

[0053] Among them, B FPosl represents the auxiliary branch pulse compression data selected according to the cancellation sample position information, B ΣPosl Indicates the sum pulse compression data selected according to the cancellation sample position information, Nos rec Indicates the theoretical noise level of the receiver.

[0054] In an exemplary embodiment of the present disclosure, the sidelobe cancellation weights are calculated using the sidelobe cancellation sample data, and the sidelobe cancellation weights are used to perform sidelobe cancellation processing on the orthogonal baseband signal after the intra-pulse interference removal processing, including:

[0055] Calculating the autocorrelation function of the auxiliary branch based on the sidelobe cancellation sample data corresponding to the auxiliary branch and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch;

[0056] Calculate the cross-correlation function between the auxiliary branch and the sidelobe cancellation sample data corresponding to the auxiliary branch and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch;

[0057] Calculating a sidelobe cancellation weight based on the autocorrelation function and the cross-correlation function;

[0058] Constructing an auxiliary branch pulse compression domain sidelobe cancellation delay signal based on the auxiliary branch pulse compression data;

[0059] Based on the auxiliary branch pulse compression data and the auxiliary branch pulse pressure domain sidelobe cancellation delay node signal, the sidelobe cancellation weight is used to perform sidelobe cancellation processing on the auxiliary branch pulse compression data.

[0060] In an exemplary embodiment of the present disclosure, the inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and the inter-pulse interference elimination processing is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation processing according to the inter-pulse interference judgment result, including:

[0061] Extracting a third signal vector of the second target clustering result and a fourth signal vector of the second interference signal clustering result;

[0062] Performing mean processing on the third signal vector and the fourth signal vector to obtain a third mean and a fourth mean;

[0063] Performing ratio processing on the third mean value and the fourth mean value to obtain a second signal fluctuation factor;

[0064] comparing the second signal fluctuation factor with a second preset threshold;

[0065] If the second signal fluctuation factor is greater than the second preset threshold, then the sum of the orthogonal baseband signals after the sidelobe cancellation processing has inter-pulse interference;

[0066] In the presence of inter-pulse interference, the fourth mean value is used as a second interference removal threshold, and interference nulling processing is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation processing based on the second interference removal threshold.

[0067] The technical solution provided by the present disclosure may have the following beneficial effects:

[0068] In the embodiment of the present disclosure, the amplitude characteristics of the interference signal of the sum-path orthogonal baseband signal are first used to complete the separation of the interference signal and the target signal through second-order clustering processing, that is, the first target clustering result and the first interference signal clustering result are obtained, and the intra-pulse interference judgment is performed based on the first target clustering result and the first interference signal clustering result, and the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference are subjected to interference zeroing processing to achieve intra-pulse interference elimination; then, the intra-pulse intermittent interference judgment is performed based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal to obtain the result of the intra-pulse intermittent interference judgment, and in the case of the presence of intra-pulse intermittent interference, the cancellation sample position is further used to eliminate the intra-pulse interference. The sidelobe cancellation sample data is obtained by using the information of the position, and then the sidelobe cancellation sample data is used to calculate the sidelobe cancellation weights, and the sidelobe cancellation weights are used to further perform sidelobe cancellation on the sum-path pulse compression data after the intra-pulse interference elimination process, so as to eliminate the intermittent interference in the pulse; finally, by performing a second-order clustering process on the sum-path orthogonal baseband signal after the intra-pulse interference elimination process and the sidelobe cancellation process, the interference signal is further separated from the target signal, and the second target clustering result and the second interference signal clustering result are obtained. The inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and the interference zeroing process is performed on each pulse with inter-pulse interference, so as to achieve the countermeasure against the intermittent noise interference. This embodiment has a strong adaptability to intermittent noise interference, and can achieve a good countermeasure effect when the interference intermittent period and duty cycle change range are relatively large.

[0069] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0071] Figure 1 A flowchart showing the steps of the intra-pulse and inter-pulse joint anti-interference method based on clustering processing in an exemplary embodiment of the present disclosure is shown;

[0072] Figure 2 The sum-path orthogonal baseband signals collected in the main-sidelobe composite discontinuous noise interference mode in the exemplary embodiment of the present disclosure are shown;

[0073] Figure 3 A schematic diagram showing the results of the orthogonal baseband signal before and after the intra-pulse interference removal process in an exemplary embodiment of the present disclosure;

[0074] Figure 4 A schematic diagram showing the results of the orthogonal baseband signal before and after the intra-pulse interference removal process and the sidelobe cancellation process in the exemplary embodiment of the present disclosure;

[0075] Figure 5 A schematic diagram showing the results of the orthogonal baseband signal of the same path before and after the intra-pulse interference elimination processing, the sidelobe cancellation processing and the inter-pulse interference elimination processing in the exemplary embodiment of the present disclosure;

[0076] Figure 6 A schematic diagram of a time-domain distance dimension profile of a target before and after being processed by the method proposed in the present disclosure in an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0077] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the disclosure will be more comprehensive and complete and to fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0078] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0079] In this example implementation, a method for joint anti-interference between intra-pulse and inter-pulse based on clustering processing is first provided. Figure 1 As shown in , the method may include the following steps:

[0080] Step S101: acquiring a sum-branch orthogonal baseband signal and an auxiliary branch orthogonal baseband signal, and performing a second-order clustering process on the sum-branch orthogonal baseband signal to obtain a first target clustering result and a first interference signal clustering result;

[0081] Step S102: performing intra-pulse interference judgment based on the first target clustering result and the first interference signal clustering result, and performing intra-pulse interference elimination processing on the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference;

[0082] Step S103: based on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, calculating the sum-branch noise mean sequence and the auxiliary branch noise mean sequence, and performing intra-pulse intermittent interference judgment;

[0083] Step S104: performing comparison processing on a plurality of noise mean values ​​in the auxiliary branch noise mean value sequence to obtain cancellation sample position information, and obtaining sidelobe cancellation sample data according to the cancellation sample position information;

[0084] Step S105: calculating a sidelobe cancellation weight using the sidelobe cancellation sample data, and performing sidelobe cancellation processing on the sum-path orthogonal baseband signal after the intra-pulse interference elimination processing using the sidelobe cancellation weight;

[0085] Step S106: performing a second-order clustering process on the sum-path orthogonal baseband signal after the sidelobe cancellation process to obtain a second target clustering result and a second interference signal clustering result;

[0086] Step S107: performing inter-pulse interference judgment based on the second target clustering result and the second interference signal clustering result, and performing inter-pulse interference elimination processing on the sum-path orthogonal baseband signal after the sidelobe cancellation processing according to the inter-pulse interference judgment result.

[0087] In the embodiment of the present disclosure, the amplitude characteristics of the interference signal of the sum-path orthogonal baseband signal are first used to complete the separation of the interference signal and the target signal through second-order clustering processing, that is, the first target clustering result and the first interference signal clustering result are obtained, and the intra-pulse interference judgment is performed based on the first target clustering result and the first interference signal clustering result, and the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference are subjected to interference zeroing processing to achieve intra-pulse interference elimination; then, the intra-pulse intermittent interference judgment is performed based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal to obtain the result of the intra-pulse intermittent interference judgment, and in the case of the presence of intra-pulse intermittent interference, the cancellation sample position is further used to eliminate the intra-pulse interference. The sidelobe cancellation sample data is obtained by using the information of the position, and then the sidelobe cancellation sample data is used to calculate the sidelobe cancellation weights, and the sidelobe cancellation weights are used to further perform sidelobe cancellation on the sum-path pulse compression data after the intra-pulse interference elimination process, so as to eliminate the intermittent interference in the pulse; finally, by performing a second-order clustering process on the sum-path orthogonal baseband signal after the intra-pulse interference elimination process and the sidelobe cancellation process, the interference signal is further separated from the target signal, and the second target clustering result and the second interference signal clustering result are obtained. The inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and the interference zeroing process is performed on each pulse with inter-pulse interference, so as to achieve the countermeasure against the intermittent noise interference. This embodiment has a strong adaptability to intermittent noise interference, and can achieve a good countermeasure effect when the interference intermittent period and duty cycle change range are relatively large.

[0088] Below, each step of the above method in this example implementation will be described in more detail.

[0089] In step S101, obtaining the orthogonal baseband signal is achieved by the following method: Assume that a coherent processing cycle of the ground pulse radar is T CPI , the number of pulses in a coherent processing cycle is N, and the pulse repetition period is T r , the gate width is T bm , the sampling frequency is F s , then the length of the orthogonal baseband signal M = F s T bm , the sum of the orthogonal baseband signals within a coherent processing cycle can be expressed as:

[0090]

[0091] Among them, A Σ Represents the amplitude matrix of the orthogonal baseband signal, A ij represents the amplitude of the sum-path orthogonal baseband signal of the j-th distance unit in the i-th pulse repetition period within the coherent processing period, the value range of i is [1, N], and the value range of j is [1, M];

[0092] The auxiliary branch orthogonal baseband signals within a coherent processing cycle can be expressed as:

[0093]

[0094] Among them, A F A represents the amplitude matrix of the auxiliary branch orthogonal baseband signal, Fij It represents the amplitude of the auxiliary branch orthogonal baseband signal of the jth range unit in the i-th pulse repetition period within the coherent processing period. The value range of i is [1, N] and the value range of j is [1, M].

[0095] Furthermore, in step S101, performing second-order clustering processing on the sum-path orthogonal baseband signal to obtain a first target clustering result and a first interference signal clustering result may include the following steps:

[0096] The obtained sum-path orthogonal baseband signals are processed for modulus value to obtain the following formula (8):

[0097]

[0098] Among them, A1 Σ represents the module value matrix of the orthogonal baseband signal, |A ij| represents the modulus value of the sum-path orthogonal baseband signal of the jth distance unit in the i-th pulse repetition period within the coherent processing period, the value range of i is [1, N], and the value range of j is [1, M];

[0099] The obtained auxiliary branch orthogonal baseband signal is processed by modulus calculation to obtain the following formula (9):

[0100]

[0101] Among them, AF1 represents the module value matrix of the auxiliary branch orthogonal baseband signal, |AF ij | represents the modulus value of the auxiliary branch orthogonal baseband signal of the jth range unit in the i-th pulse repetition period within the coherent processing period, the value range of i is [1, N], and the value range of j is [1, M];

[0102] Performing second-order clustering processing on each pulse signal modulus in the modulus matrix of the orthogonal baseband signal, to obtain a first target clustering result and a first interference signal clustering result corresponding to each pulse signal modulus;

[0103] Among them, for each pulse signal modulus in the modulus matrix of the orthogonal baseband signal, the first target clustering result obtained by the second-order clustering processing includes the first position sequence data and the first signal vector, and the first interference signal clustering result obtained by the second-order clustering processing includes the second position sequence data and the second signal vector.

[0104] It should be noted that the multiple modulus values ​​included in each row of the modulus value matrix of the orthogonal baseband signal are regarded as a pulse signal modulus value. For example, the multiple modulus values ​​included in the i-th row of the modulus value matrix of the orthogonal baseband signal are regarded as the i-th pulse signal modulus value A1. Σi .

[0105] For example, the following is the modulus value A1 of the i-th pulse signal in the modulus value matrix of the orthogonal baseband signal Σi Take the above-mentioned second-order clustering processing of the modulus values ​​of each pulse signal in the modulus value matrix of the orthogonal baseband signal as an example to obtain the first target clustering result and the first interference signal clustering result corresponding to each pulse signal modulus value. Σi Perform second-order clustering processing to obtain the modulus value A1 of the i-th pulse signal Σi The corresponding first target clustering result and the first interference signal clustering result, the modulus value A1 of the i-th pulse signal Σi The corresponding first target clustering result includes the first position sequence data idx1 i and the first signal vector A1idx1 Σi , the modulus of the i-th pulse signal is A1 ΣiThe corresponding first interference signal clustering result includes the second position sequence data idx2 i and the second signal vector A1idx2 Σi .

[0106] Specifically, in step S102, based on the first target clustering result and the first interference signal clustering result, intra-pulse interference judgment is performed, and intra-pulse interference elimination processing is performed on the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference, including:

[0107] Step S1021: extract the first signal vector of the first target clustering result and the second signal vector of the first interference signal clustering result, wherein the modulus value A1 of the i-th pulse signal in the modulus value matrix of the orthogonal baseband signal is used. Σi For example, the first signal vector of the first target clustering result extracted can be expressed as A1idx1 Σi , the second signal vector of the extracted first interference signal clustering result can be expressed as A1idx2 Σi ;

[0108] Step S1022: Perform mean processing on the first signal vector and the second signal vector to obtain a first mean and a second mean, wherein the modulus value A1 of the i-th pulse signal in the modulus value matrix of the orthogonal baseband signal is taken as Σi For example, it can be realized by the following formula (10):

[0109]

[0110] Among them, avgidx1 i Represents the first mean, mean(A1idx1 Σi ) means to find the average of the first signal vector, avgidx2 i Represents the second mean, mean(A1idx2 Σi ) represents averaging the second signal vector;

[0111] Step S1023: The first mean value is ratioed with the second mean value to obtain the first signal fluctuation factor, wherein the modulus value A1 of the i-th pulse signal in the modulus value matrix of the orthogonal baseband signal is Σi For example, it can be realized by the following formula (11):

[0112]

[0113] Among them, ratio i represents the first signal fluctuation factor;

[0114] Step S1024: performing intra-pulse interference judgment according to the first signal fluctuation factor, and performing intra-pulse interference elimination on the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference.

[0115] Further, in step S1024, performing intra-pulse interference judgment according to the first signal fluctuation factor, and removing intra-pulse interference from the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference may include the following steps:

[0116] Step S10241: comparing the first signal fluctuation factor with a first preset threshold, wherein the first preset threshold coeff1 is determined according to the radar transmission waveform and the receiver;

[0117] Step S10242: If the first signal fluctuation factor is greater than the first preset threshold, there is intra-pulse interference between the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal;

[0118] Step S10243: In the presence of intra-pulse interference, the second mean value is used as a first interference rejection threshold, and based on the first interference rejection threshold, interference zeroing processing is performed on the sum-path orthogonal baseband signal using formula (1):

[0119]

[0120] Among them, A1 Σij A1 represents the sum of the orthogonal baseband signals after interference zeroing. ij Represents the pulses of the orthogonal baseband signal, avgidx2 i represents the first interference rejection threshold;

[0121] Based on the first interference rejection threshold, interference zeroing processing is performed on the auxiliary branch orthogonal baseband signal using formula (2):

[0122]

[0123] Among them, AF1 ij It represents the auxiliary branch orthogonal baseband signal after interference nulling processing, AF ij Represents the pulses of the auxiliary branch quadrature baseband signal, avgidx2 i Represents the first interference rejection threshold.

[0124] Through step S102, after the interference signal and the target signal are separated by the second-order clustering process, the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference are set to zero to eliminate the intra-pulse interference.

[0125] It should be noted that.

[0126] In one embodiment, in step S103, based on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, calculating the sum-branch noise mean sequence and the auxiliary branch noise mean sequence, and performing intra-pulse intermittent interference judgment, may include the following steps:

[0127] Step S1031: performing pulse compression processing on the sum path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination processing to obtain sum path pulse compression data and auxiliary branch pulse compression data, wherein the sum path pulse compression data can be expressed as:

[0128]

[0129] Among them, B Σ Indicates the pulse compression data, B Σil represents the amplitude of the sum pulse compression signal of the jth range unit in the i-th pulse repetition period within the coherent processing period, and the value range of l is [1, P]; P represents the length of each pulse signal intercepted after pulse compression, which is determined by the processing capability of the radar;

[0130] The auxiliary branch pulse compression data can be expressed as:

[0131]

[0132] Among them, B F Indicates the auxiliary branch pulse compression data, B Fil represents the amplitude of the auxiliary branch pulse compression signal of the jth range unit in the i-th pulse repetition period within the coherent processing period, and the value range of l is [1, P]; P represents the length of each pulse signal intercepted after pulse compression, which is determined by the processing capability of the radar;

[0133] Step S1032: Calculate the summing path noise mean sequence and the auxiliary branch noise mean sequence using the summing path pulse compression data and the auxiliary branch pulse compression data;

[0134] Step S1033: Execute sidelobe interference judgment using formula (3):

[0135] (N Fi >ceoff2*N Σi )&&(N Fi >ceoff3*N FR )(3)

[0136] Among them, N Fi represents the noise mean of the ith pulse of the auxiliary branch, N Σi represents the noise mean of the ith pulse of the sum path, N FRrepresents the theoretical noise level of the auxiliary branch, ceoff2 represents the first noise level coefficient, specifically the ratio of the noise level of the sum branch to the auxiliary branch; ceoff3 represents the second noise level coefficient, specifically the ratio of the auxiliary branch noise level to the theoretical noise level; && represents the "and" relationship;

[0137] Step S1034: When sidelobe interference exists in the orthogonal baseband signal after the intra-pulse interference elimination process, the low noise threshold and the high noise threshold of the auxiliary branch are calculated according to the auxiliary branch noise mean sequence, and the intra-pulse intermittent interference judgment is further performed based on the high noise threshold and the low noise threshold.

[0138] Specifically, in step S1032, the summing path noise mean sequence and the auxiliary branch noise mean sequence are calculated using the summing path pulse compression data and the auxiliary branch pulse compression data, and the following steps are also included:

[0139] The mean value of the Helu pulse compression data is processed to obtain the Helu noise mean sequence:

[0140] N Σ =[N Σ1 N Σ2 LN Σi LN ΣN ](14)

[0141] Among them, N Σ represents the noise mean sequence of the sum path, specifically the noise mean of multiple pulses in the sum path, N Σi represents the noise mean of the ith pulse of the sum path in the coherent processing period, and the value range of i is [1, N];

[0142] The auxiliary branch pulse compression data is averaged to obtain the auxiliary branch noise mean sequence:

[0143] N F =[N F1 N F2 LN Fi LN FN ](15)

[0144] Among them, N F represents the auxiliary branch noise mean sequence, specifically the noise mean of multiple pulses in the auxiliary branch, N Fi It represents the noise mean of the i-th pulse of the auxiliary branch in the coherent processing period, and the value range of i is [1,N].

[0145] Specifically, when the sidelobe interference judgment is performed by the above formula (3), if the i-th pulse of the auxiliary branch satisfies the judgment condition in formula (3), the judgment is stopped and it is determined that there is sidelobe interference; if the judgment condition in formula (3) is still not satisfied until the last pulse of the auxiliary branch is traversed, it is determined that there is no sidelobe interference.

[0146] Further, in step S1034, calculating the low noise threshold and the high noise threshold of the auxiliary branch according to the auxiliary branch noise mean sequence, and performing intra-pulse intermittent interference judgment based on the high noise threshold and the low noise threshold, may include the following steps:

[0147] Step S10341: average the auxiliary branch noise level average value sequence to obtain a noise threshold, which can be expressed as:

[0148]

[0149] in, represents the noise threshold, mean(·) represents the mean value processing, N F represents the auxiliary branch noise mean sequence;

[0150] Step S10342: performing threshold processing on the auxiliary branch noise mean value sequence based on the noise threshold to obtain a low noise level mean value sequence and a high noise level mean value sequence;

[0151] Step S10343: averaging the low noise level average value sequence to obtain the low noise threshold, averaging the high noise level average value sequence to obtain the high noise threshold, and any noise level average value in the low noise level average value sequence is less than any noise level average value in the high noise level average value sequence;

[0152] Step S10344: Performing intra-pulse intermittent interference judgment according to the high noise threshold and the low noise threshold. The intra-pulse intermittent interference judgment can be performed by formula (4):

[0153]

[0154] in, Indicates the high noise threshold, represents the low noise threshold, ceoff4 represents the third noise level coefficient. If formula (4) is satisfied, there is sidelobe intermittent noise interference, otherwise it is sidelobe continuous wave interference.

[0155] Specifically, in step S10342, when the auxiliary branch noise mean sequence is subjected to threshold processing based on the above noise threshold, the noise mean sequence less than the noise threshold is The noise mean of is placed in the low noise level mean sequence and recorded as NFdown , will be greater than or equal to the noise threshold The noise mean of is placed in the high noise level mean sequence and is recorded as N Fup It should be noted that the low noise level average sequence N Fdown Any noise mean in the high noise level mean sequence is less than the above noise threshold, and any noise level mean in the high noise level mean sequence is greater than or equal to the above noise threshold. It should also be noted that after the above threshold processing, the low noise level mean sequence N Fdown and high noise level average sequence N Fup There are multiple corresponding noise means in them.

[0156] Specifically, in step S10343, the low noise level average sequence N Fdown The low noise threshold is obtained by averaging, which can be expressed as:

[0157]

[0158] in, represents the low noise threshold, mean(·) represents the mean value processing, N Fdown Represents a low-noise level average sequence;

[0159] The high noise level average sequence N Fup The high noise threshold is obtained by averaging, which can be expressed as:

[0160]

[0161] in, represents the high noise threshold, mean(·) represents the mean value processing, N Fup Represents a sequence of high-noise level averages.

[0162] Through steps S1031 to S1034, the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination processing are used to calculate the sum-branch noise mean sequence and the auxiliary branch noise mean sequence, and perform intra-pulse intermittent interference judgment to obtain the result of intra-pulse intermittent interference judgment.

[0163] After determining that the sum-path orthogonal baseband signal after the intra-pulse interference elimination process has sidelobe intermittent noise interference through the intra-pulse intermittent interference judgment in step 103, step S104 is executed to obtain sidelobe cancellation sample data.

[0164] In one embodiment, in step S104, multiple noise means in the auxiliary branch noise mean sequence are compared to obtain cancellation sample position information, including:

[0165] Step S1041: comparing multiple noise mean values ​​in the auxiliary branch noise mean value sequence to determine the maximum noise level average value;

[0166] Step S1042: Record the position information of the maximum noise level average value and use it as the cancellation sample position information.

[0167] Through the above step S1041, the maximum noise level average value N can be found from formula (15): FPos , where the maximum noise level average value N FPos is the noise mean of the Posth pulse in the auxiliary branch, that is, in step S1042, Pos can be regarded as the position information of the maximum noise level average value, and Pos is also used as the cancellation sample position information.

[0168] Furthermore, obtaining sidelobe cancellation sample data according to the cancellation sample position information in step S104 also includes:

[0169] Step S1043: selecting the auxiliary branch pulse compression data and the sum branch pulse compression data according to the cancellation sample position information;

[0170] Step S1044: screening the selected auxiliary branch pulse compression data to obtain sidelobe cancellation sample data of the auxiliary branch, and obtaining a position matrix of the sidelobe cancellation sample data of the auxiliary branch;

[0171] Step S1045: constructing the delay node data of the auxiliary branch based on the auxiliary branch pulse compression data, and selecting the delay node data of the auxiliary branch according to the position matrix to obtain the sidelobe cancellation delay node sample data of the auxiliary branch;

[0172] The sidelobe cancellation sample data includes the sidelobe cancellation sample data of the auxiliary branch and the sidelobe cancellation delay section sample data of the auxiliary branch.

[0173] Specifically, in step S1043, the auxiliary branch pulse compression data represented by formula (13) and the sum branch pulse compression data represented by formula (12) are selected according to the cancellation sample position information, specifically, the signal data of the Posth pulse in a coherent processing cycle is taken, wherein the selected auxiliary branch pulse compression data can be expressed as:

[0174] A FPos =[B FPos1 B FPos2 …B FPosl …B FPosP ](19)

[0175] Among them, B FPoslrepresents the amplitude of the auxiliary branch pulse compression signal of the jth distance unit in the Posth pulse repetition period within the coherent processing period, and the value range of l is [1, P]; P represents the length of each pulse signal intercepted after pulse compression;

[0176] The selected and-path pulse compression data can be expressed as:

[0177] A ΣPos =[B ΣPos1 B ΣPos2 …B ΣPosl …B ΣPosP ](20)

[0178] Among them, B ΣPosl It represents the amplitude of the signal after pulse compression of the j-th distance unit in the Pos-th pulse repetition period within the coherent processing period. The value range of l is [1, P]; P represents the length of each pulse signal intercepted after pulse compression.

[0179] Specifically, in step S1044, the selected auxiliary branch pulse compression data is screened to obtain the sidelobe cancellation sample data of the auxiliary branch, and the screening process is performed using formula (5):

[0180] B FPosl >Nos rec &&B FPosl >B ΣPosl (5)

[0181] Among them, B FPosl represents the auxiliary branch pulse compression data selected according to the cancellation sample position information, B ΣPosl Indicates the sum pulse compression data selected according to the cancellation sample position information, Nos rec Indicates the theoretical noise level of the receiver.

[0182] Through the above step S1044, B satisfying formula (5) FPosl is regarded as a sidelobe cancellation sample point of the auxiliary branch, and the position information of the sample point is recorded to obtain a position matrix of the sidelobe cancellation sample data of the auxiliary branch. The position matrix can be expressed as:

[0183] V=[V1 V2…V q …V Q ](twenty one)

[0184] Among them, the value range of q is [1,Q], and the value range of Q is [1,P].

[0185] It should be noted that the selected and path pulse compression data A in step S1043 need to be processed according to the position matrix V. ΣPosThen select and get the road sample data A SΣPos , for use in calculating the sidelobe cancellation weights in step S105.

[0186] Specifically, in step S1045, the delay node data of the auxiliary branch is constructed based on the auxiliary branch pulse compression data. The delay node data of the auxiliary branch can be expressed as:

[0187] A FPosD =[B FPosP B FPos2 …B FPosl …B FPos1 ](twenty two)

[0188] Among them, B FPosl represents the amplitude of the auxiliary branch pulse compressed signal of the jth distance unit in the Posth pulse repetition period within the coherent processing period, and the value range of l is [1, P];

[0189] According to the position matrix V, the delay data A of the auxiliary branch FPosD Select and obtain the sidelobe cancellation delay section sample data A of the auxiliary branch SFPosD .

[0190] In one embodiment, in step S105, the sidelobe cancellation weights are calculated using the sidelobe cancellation sample data, and the sidelobe cancellation weights are used to perform sidelobe cancellation processing on the sum-path orthogonal baseband signal after the intra-pulse interference removal processing, including:

[0191] Step S1051: calculating the autocorrelation function of the auxiliary branch based on the sidelobe cancellation sample data corresponding to the sum path, the sidelobe cancellation sample data corresponding to the auxiliary branch, and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch;

[0192] Step S1052: Calculate the cross-correlation function between the sum branch and the auxiliary branch based on the sidelobe cancellation sample data corresponding to the auxiliary branch and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch;

[0193] Step S1053: calculating a sidelobe cancellation weight based on the autocorrelation function and the cross-correlation function;

[0194] Step S1054: constructing an auxiliary branch pulse compression domain sidelobe cancellation delay node signal based on the auxiliary branch pulse compression data;

[0195] Step S1055: Based on the auxiliary branch pulse compression data and the auxiliary branch pulse pressure domain sidelobe cancellation delay node signal, use the sidelobe cancellation weight to perform sidelobe cancellation processing on the auxiliary branch pulse compression data.

[0196] It should be noted that, in combination with the aforementioned step S1031, the sum path pulse compression data used in step S1055 is obtained by performing pulse compression processing on the sum path orthogonal baseband signal after the intra-pulse interference elimination processing. Therefore, the sidelobe cancellation processing in step S1055 can be understood as: performing sidelobe cancellation processing on the sum path orthogonal baseband signal after the intra-pulse interference elimination processing.

[0197] Specifically, in step S1051, based on the sidelobe cancellation sample data A corresponding to the auxiliary branch SFPos The side lobe cancellation delay section sample data A corresponding to the auxiliary branch SFPosD Calculate the autocorrelation function of the auxiliary branch, which can be expressed as:

[0198]

[0199] Among them, R xx represents the autocorrelation function, A SFPos A represents the sidelobe cancellation sample data of the auxiliary branch, SFPosD A′ represents the sample data of the auxiliary branch sidelobe cancellation delay period. SFPos Indicates A SFPos The conjugate transpose of SFPosD Indicates A SFPosD The conjugate transpose of .

[0200] Specifically, in step S1052, based on the sidelobe cancellation sample data A of the auxiliary branch SFPos , auxiliary branch side lobe cancellation delay section sample data A SFPosD And the sample data A SΣPos , calculate the cross-correlation function between the sum path and the auxiliary branch, which can be expressed as:

[0201]

[0202] Among them, R xd represents the cross-correlation function, A SFPos A represents the sidelobe cancellation sample data of the auxiliary branch, SFPosD A′ represents the sample data of the auxiliary branch sidelobe cancellation delay period. SΣPos Indicates A SΣPos The conjugate transpose of .

[0203] Specifically, in step S1053, based on the autocorrelation function R xx and the cross-correlation function R xd Calculate the sidelobe cancellation weight, which can be expressed as:

[0204] ω opt =inv(R xx )*R xd (25)

[0205] Among them, ω opt represents the sidelobe cancellation weight, R xx represents the autocorrelation function, R xd represents the cross-correlation function and inv(g) is used to solve the inverse matrix of the matrix.

[0206] Specifically, the auxiliary branch pulse pressure domain sidelobe cancellation delay signal in step S1054 can be expressed as:

[0207]

[0208] Among them, B DF It represents the auxiliary branch pulse pressure domain sidelobe cancellation delay signal, and P represents the length of each pulse signal intercepted after pulse compression.

[0209] Specifically, in step S1055, the sidelobe cancellation processing is performed on the pulse compression data using the sidelobe cancellation weights, and the sidelobe cancellation processing is performed using formula (21):

[0210]

[0211] Among them, B Σ Indicates the pulse compression data, B F Indicates the auxiliary branch pulse compression data, B DF represents the auxiliary branch pulse pressure domain side lobe cancellation delay signal, w′ opt Represents ω opt The conjugate transpose of Σslc Represents the sum-path pulse compression data after sidelobe cancellation processing.

[0212] After obtaining the summed orthogonal baseband signal after the intra-pulse interference elimination and sidelobe cancellation processing by using steps S1051 to S1055, further perform steps S106 and S107 to further eliminate the inter-pulse interference of the summed orthogonal baseband signal after the intra-pulse interference elimination and sidelobe cancellation processing. It should be noted that the following adopts B Σslc It represents the orthogonal baseband signal after the intra-pulse interference removal and sidelobe cancellation processing.

[0213] In one embodiment, in step S106, the sum of the orthogonal baseband signals B after the intra-pulse interference removal and sidelobe cancellation processing is performed. Σslc Performing a second-order clustering process to obtain a second target clustering result and a second interference signal clustering result includes the following steps:

[0214] To B Σslc The pulse signals in are averaged to obtain j average sequences PRT_Am, where 1<j<M;

[0215] Perform a second-order clustering process on each mean sequence PRT_Am to obtain the corresponding second target clustering result and second interference signal clustering result;

[0216] Among them, the second target clustering result obtained by performing second-order clustering on each mean sequence PRT_Am includes the third position sequence data and the fourth position sequence data, and the second interference signal clustering result obtained includes the fourth position sequence data and the fourth signal vector.

[0217] In one embodiment, in step S107, inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and inter-pulse interference elimination processing is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation processing according to the inter-pulse interference judgment result, including:

[0218] Step S1071: extracting a third signal vector of the second target clustering result and a fourth signal vector of the second interference signal clustering result;

[0219] Step S1072: Perform mean processing on the third signal vector and the fourth signal vector to obtain a third mean and a fourth mean, wherein the third signal vector PRT_Amidx11 corresponding to the second target clustering result obtained by performing second-order clustering processing on the j-th mean sequence PRT_Am(j) is j The fourth signal vector PRT_Amidx12 of the clustering result of the second interference signal j For example, the calculation of the third mean and the fourth mean can be specifically implemented by the following formula (28):

[0220]

[0221] Among them, avgidx11 i Represents the third mean, mean(PRT_Amidx11 j ) represents the averaging of the third signal vector, PRT_Amidx11 j Represents the third signal vector, avgidx12 i Indicates the fourth mean, mean(PRT_Amidx12 j ) represents the averaging of the fourth signal vector, PRT_Amidx12 j represents a fourth signal vector;

[0222] Step S1073: performing ratio processing on the third mean and the fourth mean to obtain the second signal fluctuation factor, which can be specifically implemented by the following formula (29):

[0223]

[0224] Among them, ratioN i represents the second signal fluctuation factor;

[0225] Step S1074: comparing the second signal fluctuation factor with a second preset threshold coeff5, wherein the second preset threshold coeff5 is determined according to the radar transmission waveform and the receiver;

[0226] Step S1075: If the second signal fluctuation factor is greater than the second preset threshold, the orthogonal baseband signal B after the intra-pulse interference removal and sidelobe cancellation processing is Σslc There is inter-pulse interference;

[0227] Step S1076: In the presence of inter-pulse interference, the fourth average avgidx12 i as the second interference rejection threshold, and based on the second interference rejection threshold, the sum of the orthogonal baseband signals B after the intra-pulse interference rejection processing and the sidelobe cancellation processing is processed. Σslc Perform interference zeroing processing.

[0228] Specifically, in step S1076, the interference nulling process is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation process based on the second interference rejection threshold as follows:

[0229] B Σslc Compare each pulse signal in B with the second interference rejection threshold; Σslc The pulse signals in B that are greater than the second interference rejection threshold are reset to zero. Σslc The pulse signals that are less than or equal to the second interference rejection threshold are retained.

[0230] Through steps S1071 to S1076, after the intra-pulse interference elimination processing in step S102 and the sidelobe cancellation processing in step S105, the orthogonal baseband signal with inter-pulse interference is further eliminated to eliminate the inter-pulse interference signal, so that the target signal can be detected normally.

[0231] In the embodiment of the present application, in order to further verify the effect of the method for counteracting the sidelobe intermittent noise interference of the ground radar proposed in the present application on the sidelobe intermittent noise interference, a simulation experiment was carried out, and the coherent processing cycle of the pulse radar was set to 11.2ms. CPI The number of transmitted pulses is N = 10, the pulse width tau = 153 μs, and the gate width is T bm =165μs, sampling frequency F s =20MHz. Then the length of the baseband signal sampling points in one pulse repetition period is M=3300.

[0232] The simulation data and simulation results in this simulation experiment are referenced Figures 2 to 6 As shown:

[0233] Specifically, Figure 2 The figure shows the orthogonal baseband signals collected in the main-sidelobe composite intermittent noise interference mode. Figure 3 The figure shows the result of the orthogonal baseband signal before and after the intra-pulse interference removal process. Figure 4 The figure shows the result of the orthogonal baseband signal before and after the intra-pulse interference removal and sidelobe cancellation processing. Figure 5 The figure shows the result of the orthogonal baseband signal before and after the intra-pulse interference removal, sidelobe cancellation and inter-pulse interference removal. Figure 6 FIG. 2 shows a schematic diagram of a target time domain distance dimension profile before and after being processed using the method proposed in the present disclosure. Figure 6 It can be seen that before being processed using the method proposed in the present disclosure, the target envelope is submerged in the main sidelobe intermittent noise interference, and the target cannot be detected. After being processed using the method proposed in the present disclosure, the intermittent noise interference is effectively suppressed and the target signal can be detected normally.

[0234] Regarding the system in the above embodiment, the specific manner in which each unit performs operations has been described in detail in the embodiment of the method, and will not be elaborated here.

[0235] It should be noted that although several units of the system for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiment of the present disclosure, the features and functions of two or more units described above can be concretized in one unit. Conversely, the features and functions of a unit described above can be further divided into multiple units for concretization. Some or all of the units can be selected according to actual needs to achieve the purpose of the disclosed solution. Those of ordinary skill in the art can understand and implement it without paying creative work.

[0236] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A method for joint anti-interference between intra-pulse and inter-pulse based on clustering processing, characterized in that: include: Acquire the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal, and perform second-order clustering processing on the sum-branch orthogonal baseband signal to obtain a first target clustering result and a first interference signal clustering result; Performing intra-pulse interference judgment based on the first target clustering result and the first interference signal clustering result, and performing intra-pulse interference elimination processing on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference; Based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, calculate the sum-path noise mean sequence and the auxiliary branch noise mean sequence, and perform intra-pulse intermittent interference judgment; Comparing multiple noise means in the auxiliary branch noise mean sequence, obtaining cancellation sample position information, and obtaining sidelobe cancellation sample data according to the cancellation sample position information; Calculating a sidelobe cancellation weight using the sidelobe cancellation sample data, and performing sidelobe cancellation processing on the sum-path orthogonal baseband signal after the intra-pulse interference elimination processing using the sidelobe cancellation weight; Performing second-order clustering processing on the sum-path orthogonal baseband signal after the sidelobe cancellation processing to obtain a second target clustering result and a second interference signal clustering result; An inter-pulse interference judgment is performed based on the second target clustering result and the second interference signal clustering result, and an inter-pulse interference elimination process is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation process according to the inter-pulse interference judgment result.

2. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 1 is characterized in that: The performing of intra-pulse interference judgment based on the first target clustering result and the first interference signal clustering result, and performing intra-pulse interference elimination processing on the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference, comprises: Extracting a first signal vector of the first target clustering result and a second signal vector of the first interference signal clustering result; Performing mean processing on the first signal vector and the second signal vector to obtain a first mean and a second mean; Performing ratio processing on the first mean value and the second mean value to obtain a first signal fluctuation factor; Intra-pulse interference judgment is performed according to the first signal fluctuation factor, and intra-pulse interference is eliminated for the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal with intra-pulse interference.

3. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 2 is characterized in that: The performing of intra-pulse interference judgment according to the first signal fluctuation factor and performing intra-pulse interference elimination on the sum branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal having intra-pulse interference comprises: Comparing the first signal fluctuation factor with a first preset threshold; If the first signal fluctuation factor is greater than the first preset threshold, there is intra-pulse interference between the sum-branch orthogonal baseband signal and the auxiliary branch orthogonal baseband signal; In the presence of intra-pulse interference, the second mean value is used as the first interference removal threshold, and based on the first interference removal threshold, interference zeroing processing is performed on the sum-path orthogonal baseband signal using formula (1): Among them, A1 Σij A1 represents the sum of the orthogonal baseband signals after interference zeroing. ij Represents the pulses of the orthogonal baseband signal, avgidx2 i represents the first interference rejection threshold; Based on the first interference rejection threshold, interference zeroing processing is performed on the auxiliary branch orthogonal baseband signal using formula (2): Among them, AF1 ij It represents the auxiliary branch orthogonal baseband signal after interference nulling processing, AF ij Represents the pulses of the auxiliary branch quadrature baseband signal, avgidx2 i Represents the first interference rejection threshold.

4. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 1 is characterized in that: Based on the sum-path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination process, a sum-path noise mean sequence and an auxiliary branch noise mean sequence are calculated, and intra-pulse intermittent interference judgment is performed, including: Performing pulse compression processing on the sum path orthogonal baseband signal and the auxiliary branch orthogonal baseband signal after the intra-pulse interference elimination processing to obtain sum path pulse compression data and auxiliary branch pulse compression data; Calculating a summing path noise mean sequence and an auxiliary branch noise mean sequence using the summing path pulse compression data and the auxiliary branch pulse compression data; The side lobe interference judgment is performed by formula (3): (N Fi >ceoff2*N Σi )&&(N Fi >ceoff3*N FR )(3) Among them, N Fi represents the noise mean of the ith pulse of the auxiliary branch, N Σi represents the noise mean of the ith pulse of the sum path, N FR represents the theoretical noise level of the auxiliary branch, ceoff2 represents the first noise level coefficient, and ceoff3 represents the second noise level coefficient; When sidelobe interference exists, a low noise threshold and a high noise threshold of the auxiliary branch are calculated according to the auxiliary branch noise mean sequence, and intra-pulse intermittent interference judgment is performed based on the high noise threshold and the low noise threshold.

5. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 4 is characterized in that: The step of calculating the low noise threshold and the high noise threshold of the auxiliary branch according to the auxiliary branch noise mean sequence, and performing intra-pulse intermittent interference judgment based on the high noise threshold and the low noise threshold, comprises: The auxiliary branch noise mean sequence is averaged to obtain a noise threshold; Based on the noise threshold, the auxiliary branch noise mean value sequence is subjected to threshold processing to obtain a low noise level mean value sequence and a high noise level mean value sequence; The low noise level average value sequence is averaged to obtain the low noise threshold, and the high noise level average value sequence is averaged to obtain the high noise threshold, wherein any noise level average value in the low noise level average value sequence is less than any noise level average value in the high noise level average value sequence; The intermittent interference judgment within the pulse is performed by formula (4): in, Indicates the high noise threshold, represents the low noise threshold, ceoff4 represents the third noise level coefficient, and if formula (4) is satisfied, there is sidelobe intermittent noise interference.

6. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 4 is characterized in that: The comparing and processing multiple noise means in the auxiliary branch noise mean sequence to obtain cancellation sample position information includes: Comparing multiple noise mean values ​​in the auxiliary branch noise mean value sequence to determine the maximum noise level average value; The position information of the maximum noise level average value is recorded and used as the cancellation sample position information.

7. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 6 is characterized in that: The acquiring of sidelobe cancellation sample data according to the cancellation sample position information further includes: Selecting the auxiliary branch pulse compression data and the sum branch pulse compression data according to the cancellation sample position information; Screening the selected auxiliary branch pulse compression data to obtain sidelobe cancellation sample data of the auxiliary branch, and obtaining a position matrix of the sidelobe cancellation sample data of the auxiliary branch; Constructing the delay node data of the auxiliary branch based on the auxiliary branch pulse compression data, and selecting the delay node data of the auxiliary branch according to the position matrix to obtain the sidelobe cancellation delay node sample data of the auxiliary branch; The sidelobe cancellation sample data includes the sidelobe cancellation sample data of the auxiliary branch and the sidelobe cancellation delay section sample data of the auxiliary branch.

8. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 7 is characterized in that: In the step of screening the selected auxiliary branch pulse compression data to obtain the sidelobe cancellation sample data of the auxiliary branch, the screening process is performed using formula (5): B FPosl >Nos rec &&B FPosl >B ΣPosl (5) Among them, B FPosl represents the auxiliary branch pulse compression data selected according to the cancellation sample position information, B ΣPosl Indicates the sum pulse compression data selected according to the cancellation sample position information, Nos rec Indicates the theoretical noise level of the receiver.

9. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 7, characterized in that: The method of calculating a sidelobe cancellation weight using the sidelobe cancellation sample data, and performing sidelobe cancellation processing on the sum-path orthogonal baseband signal after the intra-pulse interference elimination processing using the sidelobe cancellation weight, comprises: Calculating the autocorrelation function of the auxiliary branch based on the sidelobe cancellation sample data corresponding to the auxiliary branch and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch; Calculate the cross-correlation function between the auxiliary branch and the sidelobe cancellation sample data corresponding to the auxiliary branch and the sidelobe cancellation delay node sample data corresponding to the auxiliary branch; Calculating a sidelobe cancellation weight based on the autocorrelation function and the cross-correlation function; Constructing an auxiliary branch pulse compression domain sidelobe cancellation delay signal based on the auxiliary branch pulse compression data; Based on the auxiliary branch pulse compression data and the auxiliary branch pulse pressure domain sidelobe cancellation delay node signal, the auxiliary branch pulse compression data is subjected to sidelobe cancellation processing using the sidelobe cancellation weight.

10. The intra-pulse and inter-pulse joint anti-interference method based on clustering processing according to claim 1, characterized in that: The performing of inter-pulse interference judgment based on the second target clustering result and the second interference signal clustering result, and performing inter-pulse interference elimination processing on the sum-path orthogonal baseband signal after the sidelobe cancellation processing according to the inter-pulse interference judgment result, includes: Extracting a third signal vector of the second target clustering result and a fourth signal vector of the second interference signal clustering result; Performing mean processing on the third signal vector and the fourth signal vector to obtain a third mean and a fourth mean; Performing ratio processing on the third mean value and the fourth mean value to obtain a second signal fluctuation factor; comparing the second signal fluctuation factor with a second preset threshold; If the second signal fluctuation factor is greater than the second preset threshold, then the sum of the orthogonal baseband signals after the sidelobe cancellation processing has inter-pulse interference; In the presence of inter-pulse interference, the fourth mean value is used as a second interference removal threshold, and interference nulling processing is performed on the sum-path orthogonal baseband signal after the sidelobe cancellation processing based on the second interference removal threshold.

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