A method and device for resisting high repetition frequency interference of a laser guidance radar

Abstract

The application discloses a kind of laser guidance radar's anti high frequency interference method and device, method includes: receiving multiple echo signals and according to multiple echo signals real-time setting multiple self-adapting overlapping wave gates;Echo signal is the signal formed after reflection for the pulsed signal that laser target indicator emits in random frequency mode;According to multiple wave gates, obtain multiple candidate pulse echo combinations from multiple echo signals;According to each echo signal and the target distance of target to be hit, with the motion attribute of seeker for hitting target to be hit, obtain target pulse echo combination from multiple candidate pulse echo combinations;According to target pulse echo combination, determine the position of target to be hit.The application can improve the anti high frequency interference ability of laser guidance system, realize accurate laser guidance, and can be widely applied in laser guidance field.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of laser guidance, in particular to a method and device for resisting high-repetition-frequency interference of laser guidance radar. BACKGROUND

[0002] Laser semi-automatic guidance is a typical laser guidance system, whose basic principle is that a laser beam is emitted by a laser target designator located on an aircraft or the ground to irradiate a target, and a detector located in a seeker receives the laser signal diffused by the target. The detector realizes the capture of the target by processing multiple pulse echoes in the receiving gate. After realizing the capture of the target, the target is tracked by continuous confirmation. The laser guidance system has the characteristics of high precision, simple structure and low cost. In the actual application environment, the scattering signals of other laser target designators and the signals emitted by laser jamming machines may affect the performance of the detector. The former is non-malicious interference and has a low-repetition-frequency interference effect; the latter usually works in a high-repetition-frequency mode to ensure the interference effect. The high-repetition-frequency laser interference emitted by the latter jamming machine brings great interference to the current laser guidance radar due to the advantages that the guidance parameters such as the repetition frequency and code type of the opponent do not need to be known. Influenced by the motion of the laser target designator, the target and the detector, different pulse echoes usually have differences in time delay. When continuous pulses appear in a specific gate, the detector enters a pulse locking state, and realizes the capture of the target by the correlation of continuous detection of echoes in the locking gate. The jamming machine generates a large number of dense false target signals in the detector receiving gate by emitting high-repetition-frequency interference signals, so as to break the target capture and tracking link of the laser radar with a high probability, and seriously affect the guidance efficiency of the laser guidance system.

[0003] Figure 1 The principle diagram of high-repetition-frequency interference is shown. Figure 1 In the diagram, the horizontal axis is the time axis, and the rectangular frame is the time gate, wherein Figure 1 (a) of the diagram shows the case that the detector receives the target echo signal without interference, and at this time, the target echo signal is well received by the set gate; Figure 1 (b) of the diagram shows the characteristics of high-repetition-frequency interference signals, that is, the higher the repetition frequency, the more densely distributed on the time axis; Figure 1 (c) of the diagram shows that when the detector sets the gate to record the echo signal in the high-repetition-frequency interference scenario, part of the interference signals enter the receiving gate.

[0004] The current technical approach of laser guidance anti-jamming mainly includes two aspects: one is to encode the indicator transmission signal, to improve the information entropy of the target echo signal, and to reduce the similarity between the jamming signal and the target echo; the other is to fully exploit the characteristic information of the target echo signal in the target acquisition and tracking processing link, and to eliminate the jamming signal that does not meet the target characteristics. At present, the common method is to analyze the received signal, estimate the frequency of the high repetition frequency jamming signal, and filter out the jamming signal through the reverse repetition frequency pulse signal circuit. The current anti-jamming method has the following problems: in recent years, the research focus of researchers is more on laser coding, and the laser coding and the detector signal processing part are not well combined; the detector signal processing link mostly uses fixed width wave gate and conventional single pulse locking method to acquire and track the target, and there is a problem of easy loss of target echo signal; the motion characteristics of laser target indicator, target and detector are not fully utilized to distinguish the jamming signal; the random repetition frequency jamming adds random time jitter on the basis of fixed repetition frequency jamming, and the applicability of the anti-jamming algorithm in the random repetition frequency jamming scene is less considered, for example, the anti-jamming technology using the reverse repetition frequency pulse signal circuit as the interference elimination means can only eliminate the high repetition frequency jamming of a single frequency, and such means cannot adapt to the random repetition frequency jamming scene. SUMMARY

[0005] Therefore, the embodiment of the present application provides a laser guidance radar anti-high repetition frequency jamming method and device, which is used for improving the anti-high repetition frequency jamming capability of the laser guidance system and realizing precise laser guidance.

[0006] An aspect of the embodiment of the present application provides a laser guidance radar anti-high repetition frequency jamming method, which comprises the following steps.

[0007] receiving a plurality of echo signals and setting a plurality of self-adaptive overlapping wave gates in real time according to the plurality of echo signals; the echo signal is a signal formed after the pulse signal emitted by a laser target indicator in a random repetition frequency mode is reflected;

[0008] obtaining a plurality of candidate pulse echo combinations from the plurality of echo signals according to the plurality of wave gates;

[0009] obtaining a target pulse echo combination from the plurality of candidate pulse echo combinations according to the target distance of each echo signal and the target to be hit and the motion attribute of a seeker used to hit the target to be hit;

[0010] determining the position of the target to be hit according to the target pulse echo combination.

[0011] Optionally, the step of receiving a plurality of echo signals and setting a plurality of self-adaptive overlapping wave gates in real time according to the plurality of echo signals comprises the following steps.

[0012] receiving four echo signals in time sequence;

[0013] The first gate, the second gate, the third gate and the fourth gate correspond to the first echo signal, the second echo signal, the third echo signal and the fourth echo signal respectively.

[0014] The opening time and the closing time of the second gate, the opening time and the closing time of the third gate and the opening time and the closing time of the fourth gate are determined according to the first signal time and the last signal time received in the corresponding previous gate.

[0015] Optionally, the opening time and the closing time of the second gate, the opening time and the closing time of the third gate and the opening time and the closing time of the fourth gate are determined according to the first signal time and the last signal time received in the corresponding previous gate, comprising:

[0016] The opening time and the closing time of the second gate, the opening time and the closing time of the third gate and the opening time and the closing time of the fourth gate are determined according to the gate setting expression, wherein the gate setting expression is:

[0017]

[0018] Wherein, T g1 and T g2 are the opening time and the closing time of the current gate respectively, Δt is the gate width, t start and t end are the first signal time and the last signal time received in the previous gate respectively, T l+1 and T l represent the transmission time of the pulse signal corresponding to the echo signal received by the current gate and the pulse period of the pulse signal corresponding to the echo signal received by the previous gate respectively.

[0019] Optionally, the multiple candidate pulse echo combinations are obtained from the multiple echo signals through the multiple gates, comprising:

[0020] An effective echo signal of the target to be hit is received through the first gate.

[0021] A plurality of echo signals are received through the second gate, a plurality of echo signals are received through the third gate, and a plurality of echo signals are received through the fourth gate.

[0022] An echo signal is selected from the first gate to the fourth gate in sequence each time to obtain multiple candidate pulse echo combinations.

[0023] Optionally, the obtaining the target pulse echo combination from the multiple candidate pulse echo combinations according to each of the echo signals and a target distance to a target to be hit, and a motion attribute of a seeker used to hit the target to be hit, comprises:

[0024] determining the target distance to the target to be hit according to a transmission time of a corresponding pulse signal of each of the pulse echo combinations and a delay relationship between the pulse signals;

[0025] obtaining multiple first motion attributes of the pulse signal corresponding to each of the echo signals according to each of the target distances and a pre-established motion model;

[0026] comparing each of the first motion attributes with a second motion attribute of the seeker;

[0027] if a difference obtained by the comparison is less than a preset threshold, determining the pulse echo combination corresponding to the first motion attribute as the target pulse signal combination.

[0028] Optionally, the method further comprises:

[0029] if there are three or more echo signals in the candidate pulse echo combination that are the same as echo signals in a real pulse echo combination, determining the candidate pulse echo combination as the target pulse echo combination; the real pulse echo combination is composed of pulse echoes corresponding to the target to be hit.

[0030] Another aspect of the embodiment of the application further provides another anti-high-repetition-frequency interference method for a laser guidance radar, comprising:

[0031] transmitting pulse signals in a random repetition frequency manner;

[0032] wherein, a period of the pulse signals is T=[T1, T2, T3…T K-1 ] T a superscript T represents vector transposition, T k is a repetition period of the k-1th and kth pulse signals, and T min <T k <T max , T min and T max are a minimum period and a maximum period of a laser target indicator transmission signal respectively, T life is an effective transmission time of the pulse signals.

[0033] Optionally, the transmitting pulse signals in a random repetition frequency manner comprises:

[0034] The pulse signal is transmitted in a random repetition frequency mode according to a waveform transmission expression;

[0035] The waveform transmission expression is:

[0036]

[0037] Wherein, t k represents a transmission delay time of the kth pulse signal relative to the 0th pulse signal, and the transmission time of the 0th pulse signal is taken as a starting time, T0=0, m represents the mth transmitted pulse signal, T m represents a repetition period of the m-1th pulse signal to the mth pulse signal.

[0038] Another aspect of the embodiment of the present application further provides an anti-high-repetition-frequency interference device of a laser guidance radar, comprising:

[0039] A first unit is configured to receive a plurality of echo signals and set a plurality of adaptive overlapping wave gates in real time according to the plurality of echo signals; the echo signal is a signal formed after a pulse signal transmitted by a laser target indicator in a random repetition frequency mode is reflected;

[0040] A second unit is configured to obtain a plurality of candidate pulse echo combinations from the plurality of echo signals according to the plurality of wave gates;

[0041] A third unit is configured to obtain a target pulse echo combination from the plurality of candidate pulse echo combinations according to a target distance of each echo signal to a target to be hit and a motion attribute of a seeker used to hit the target to be hit;

[0042] A fourth unit is configured to determine a position of the target to be hit according to the target pulse echo combination.

[0043] Another aspect of the embodiment of the present application further provides another anti-high-repetition-frequency interference device of a laser guidance radar, comprising:

[0044] A fifth unit is configured to transmit a pulse signal in a random repetition frequency mode;

[0045] Wherein, a period of the pulse signal is T=[T1, T2, T3…T K-1 ] T The superscript T represents vector transposition, T k is a repetition period of the k-1th and kth pulse signals, and T min <T k <T max , T min and T max are minimum and maximum periods of a signal transmitted by a laser target indicator, respectively, T life is the effective transmission time of the pulse signal.

[0046] Another aspect of the embodiment of the present application further provides an electronic device, comprising a processor and a memory;

[0047] The memory is used for storing a program.

[0048] The processor executes the program to realize the method.

[0049] Another aspect of the embodiment of the present application further provides a computer readable storage medium, the storage medium stores a program, and the program is executed by a processor to realize the method.

[0050] The embodiment of the present application further discloses a computer program product or a computer program, which comprises computer instructions stored in a computer readable storage medium. A processor of a computer device can read the computer instructions from the computer readable storage medium, and the processor executes the computer instructions, so that the computer device executes the foregoing method.

[0051] In view of the defects of the prior art, the present application can randomly transmit a signal at a high frequency, and under the condition of quasi-synchronization of transmission and reception, a high-frequency interference discrimination and target detection method based on an adaptive overlapping gate is proposed in combination with the motion characteristics of a laser target indicator, a target to be hit and a detector. In view of the defects of the prior art, the present application at least has the following effects:

[0052] 1. The pulse coding technology is combined to transmit a pulse signal at a random high frequency, and the pulse transmission time is used as prior information to process the pulse signal in a seeker.

[0053] 2. An adaptive overlapping gate is proposed, and all pulses received in the gate are considered in combination compared to the prior art of capturing a guidance signal pulse by using a single pulse locking technology.

[0054] 3. In the discrimination of an interference signal, the target distance between an echo signal and a target to be hit and the motion attribute of the seeker are used to filter out the interference signal.

[0055] 4. The present application can effectively screen and remove an interference signal under a random high-frequency interference scene, and has strong anti-interference performance. BRIEF DESCRIPTION OF DRAWINGS

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly introduced. Obviously, the drawings in the following description only constitute some embodiments of the present application, and for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 A high-repetition-frequency interference principle diagram provided for the embodiments of the present application;

[0058] Figure 2 A target capture schematic diagram in a high-repetition-frequency interference scenario provided for the embodiments of the present application;

[0059] Figure 3 A parameter relationship schematic diagram of a transmitted signal provided for the embodiments of the present application;

[0060] Figure 4 A flowchart of an anti-high-repetition-frequency interference method of a laser guidance radar provided for the embodiments of the present application;

[0061] Figure 5 An adaptive overlapping wave gate diagram provided for the embodiments of the present application;

[0062] Figure 6 A signal judgment flowchart provided for the embodiments of the present application;

[0063] Figure 7 A structural block diagram of an anti-high-repetition-frequency interference device of a laser guidance radar provided for the embodiments of the present application. DETAILED DESCRIPTION

[0064] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0065] It should be noted that although the functional modules are divided in the device schematic diagram, and the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a manner different from the module division in the device or the order in the flowchart.

[0066] The terms "first", "second", and the like in the description and in the claims of the application and above-described drawings are used to distinguish similar objects and are not necessarily used to describe a particular sequential or chronological order. Also, the terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by an occurrence of "comprising" does not exclude the existence of additional identical elements in the process, method, article, or apparatus including the element.

[0067] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the specification is for the purpose of describing embodiments of the present application only and is not intended to be limiting of the present application.

[0068] Before further describing the embodiments of the present application, the terms and phrases involved in the embodiments of the present application are explained, and the terms and phrases involved in the embodiments of the present application are applicable to the following explanations:

[0069] Semi-active guidance: In the last stage of approaching the target, semi-active guidance is a terminal guidance mode of a missile system. Semi-active guidance is to radiate a laser signal to a region where one or more targets may exist using a laser target designator. The missile is equipped with a seeker receiver and a detector, which can guide the missile to the target by using the signal reflected by the target.

[0070] Time gate: Time gate technology is a technology commonly used by laser guidance seekers. The gate controls the reception of the indication signal, and the gate is opened only at the time when the indication signal reaches the seeker, and is closed after receiving the indication signal, and no signal is received during the gate closing period.

[0071] High repetition frequency interference: High repetition frequency laser is to emit high repetition frequency pulsed laser to a semi-active guidance missile, so that the guidance gate of the missile is interfered by the high repetition frequency signal at any time, thereby affecting the reception of the indication signal by the seeker, reducing the interception probability of the target information by the seeker, and causing the laser semi-active guidance missile to be deflected due to the extraction of interference information, so as to achieve the purpose of protecting the attacked target.

[0072] In order to facilitate the understanding of the working process of the present application, the application scenario of the present application is introduced first, please refer to Figure 2 , Figure 2 is a schematic diagram of target capture in the repetition frequency interference scenario.

[0073] The laser target designator randomly modulates the transmitting pulse, transmits a random repetition frequency laser signal beam to irradiate the target, and the detector of the seeker receives the target signal reflected by the target. The jammer transmits high repetition frequency jamming signals to interfere with the laser guided weapon, and the detector can also receive the jamming signals. The seeker receives the guidance signals reflected from the target and the jamming signals transmitted by the high repetition frequency jammer, and sends the superimposed echo signals to the information processing module. In the signal processing module, the interference is excluded and the echo is decoded by using the prior information of the transmitting signal, so that the target acquisition and reliable tracking are realized.

[0074] The differences between the present application and the prior art include: the laser target designator transmits a random repetition frequency laser waveform; and the process of the signal processing module processing the echo signal. The present application proposes an adaptive overlapping wave gate and successfully acquires the target in the superimposed echo signal by using motion prior information, which is described in detail as follows:

[0075] The embodiment of the present application provides an anti-high repetition frequency jamming method of a laser guided radar, which is applied to a laser target designator in Figure 2 , and specifically includes the following steps:

[0076] Transmit a pulse signal in a random repetition frequency mode.

[0077] The period of the pulse signal is T=[T1, T2, T3…T K-1 ] T The superscript T represents vector transposition, T k is the repetition period of the k-1th and kth pulse signals, and T min <T k <T max , T min and T max are the minimum period and the maximum period of the transmitting signal of the laser target designator, T life is the effective transmitting time of the pulse signal.

[0078] As a further optional implementation manner, the transmitting the pulse signal in the random repetition frequency mode comprises:

[0079] Transmit the pulse signal in the random repetition frequency mode according to a waveform transmitting expression;

[0080] The waveform transmitting expression is:

[0081]

[0082] Wherein, t krepresents the transmission delay time of the kth pulse signal relative to the 0th pulse signal, with the transmission time of the 0th pulse signal as the starting time, T0=0, m represents the mth transmitted pulse signal, T m represents the repetition period of the m-1th pulse signal to the mth pulse signal.

[0083] Exemplarily, the process of transmitting the pulse signal in the random repetition frequency mode by the embodiment of the application is described.

[0084] Specifically, the laser target indicator transmits the signal in the random repetition frequency mode, that is, the pulse period is T=[T1, T2, T3,..., Tn], where T1, T2, T3,..., Tn are random values. K-1 ] T , where the superscript T represents vector transposition, T k is the repetition period of the k-1th and kth pulses, and T min <T k <T max , T min and T max are the total working time of the laser target indicator, and T Due to the engineering limitations such as propagation loss, target scattering characteristics, transmission power, and detector sensitivity, the maximum time delay τ max =2R e / C=T minn , where C is the speed of light, and R e is the effective detection distance. The schematic diagram of the relationship between the transmission signal, the pulse repetition period, and the maximum detection distance is shown in FIG. 2. Figure 3 .

[0085] Suppose that the transmission pulse signal waveform is x(t), and the transmission waveform is:

[0086]

[0087] where t k represents the transmission delay of the kth pulse relative to the 0th pulse, with the transmission time of the 0th pulse as the starting time, T0=0.

[0088] Referring to FIG. 1, Figure 4 the embodiment of the application provides another anti-high-repetition-frequency interference method for the laser guidance radar, which is applied to the signal processing module in Figure 2 , and specifically includes the following steps:

[0089] S100: receiving a plurality of echo signals and setting a plurality of self-adaptive overlapping wave gates in real time according to the plurality of echo signals; the echo signal is a signal formed after a pulse signal transmitted by a laser target indicator in a random repetition frequency mode is reflected.

[0090] Specifically, the step S100 can include:

[0091] S1, receiving four echo signals in time sequence.

[0092] Wherein, the wave gate corresponding to receiving four echo signals are respectively the first wave gate, the second wave gate, the third wave gate and the fourth wave gate; the first signal time of the corresponding echo signal received by the first wave gate is taken as the opening time of the first wave gate, and the last signal time of the corresponding echo signal received by the first wave gate is taken as the closing time of the first wave gate.

[0093] S2, determining the opening time and closing time of the second wave gate, the opening time and closing time of the third wave gate and the opening time and closing time of the fourth wave gate according to the first signal time and the last signal time received in the corresponding previous wave gate.

[0094] Further, the above S2, determining the opening time and closing time of the second wave gate, the opening time and closing time of the third wave gate and the opening time and closing time of the fourth wave gate according to the first signal time and the last signal time received in the corresponding previous wave gate, can include:

[0095] Determining the opening time and closing time of the second wave gate, the opening time and closing time of the third wave gate and the opening time and closing time of the fourth wave gate according to the wave gate setting expression, the wave gate setting expression is:

[0096]

[0097] Wherein, T g1 and T g2 are the opening time and closing time of the current wave gate respectively, Δt is the wave gate width, t start and t end are the first signal time and the last signal time received by the previous wave gate respectively, T l+1 and T l represent the emission time of the pulse signal corresponding to the echo received by the current wave gate and the pulse period of the pulse signal corresponding to the echo received by the previous wave gate respectively.

[0098] For the convenience of understanding the determination process of the adaptive overlapping wave gate in the embodiment of the application, the embodiment of the application will illustrate the process with specific examples.

[0099] Specifically, for the transmission laser sequence with the pulse repetition period T = [T1, T2, L, T K-1 ] T , assuming that the first signal time received in the receiving wave gate of the lth pulse is t start, the time of the last signal is t end , the wave gate of the (l+1)th pulse can be set in real time as follows:

[0100]

[0101] wherein, T g1 and T g2 are the opening time and the closing time of the real-time wave gate of the (l+1)th pulse, and Δt is the wave gate width. An example diagram of the adaptive overlapping wave gate is shown in Figure 5 .

[0102] S210: obtaining a plurality of candidate pulse echo combinations from a plurality of echo signals according to a plurality of wave gates.

[0103] Specifically, it can include:

[0104] S1, receiving an effective echo signal of the to-be-hit target through the first wave gate.

[0105] S2, receiving a plurality of echo signals through the second wave gate, receiving a plurality of echo signals through the third wave gate, and receiving a plurality of echo signals through the fourth wave gate.

[0106] S3, selecting one echo signal from the first wave gate to the fourth wave gate in order each time to obtain a plurality of candidate pulse echo combinations.

[0107] Specifically, still taking the example shown in Figure 5 , it is assumed that after the lth pulse is transmitted, the 1st echo is received within the effective detection range of the lth pulse. Taking the 1st echo as the reference time, the receiving wave gate of the (l+1)th pulse is set in real time, and the 2nd and 3rd echoes are received within this wave gate. Taking the 2nd and 3rd echoes as the reference to determine the opening time and the closing time of the receiving wave gate of the (l+2)th pulse, and the 4th, 5th and 6th echoes are received within this wave gate. In this way, the recursion is carried out, and after the (l+3)th pulse is transmitted, the 7th, 8th, 9th and 10th echoes can be received by the detector. Therefore, after the 1st echo is considered as a suspected target echo, there are 4! = 24 kinds of pulse combinations obtained by the adaptive overlapping wave gate. The receiver takes the echoes of the four transmitted pulses as the necessary condition for target capture, and after the four pulses are transmitted, a plurality of pulse combinations are collected within the wave gate corresponding to the transmitted pulses to enter the signal judgment link.

[0108] S220: obtaining a target pulse echo combination from a plurality of candidate pulse echo combinations according to the target distance of each echo signal to the to-be-hit target and the motion attribute of the seeker used to hit the to-be-hit target.

[0109] Specifically, it can include:

[0110] S1, determine a target distance of each of the echo signals to the target to be hit according to a transmission time of a corresponding pulse signal of each of the pulse echo combinations and a delay relationship between the pulse signals.

[0111] S2, obtain a plurality of first motion attributes of the pulse signal corresponding to each of the echo signals according to each of the target distances and a pre-established motion model.

[0112] S3, compare each of the first motion attributes with a second motion attribute of the seeker.

[0113] S4, if a difference obtained by the comparison is less than a preset threshold, determine the pulse echo combination corresponding to the first motion attribute as the target pulse signal combination.

[0114] To facilitate the description of the process of obtaining the target pulse echo combination in the embodiments of the present application, further description will be made.

[0115] Referring to Figure 6 , the embodiments of the present application provide a signal decision flowchart.

[0116] Specifically, after determining the adaptive overlapping wave gate, a plurality of echo combinations containing the target, the interference and the noise can be obtained. In the signal processing module, the processor needs to analyze the received signals in the continuous four pulse receiving wave gates. Since the fixed frequency interference signals and the random frequency interference signals in the continuous four pulse receiving wave gates can continuously satisfy the echo rule of the real target, the signal decision algorithm based on the prior information can preferably extract the real target. The transmission pulse timing T = [T1, T2, L, T K-1 ] T It is known that the fixed frequency interference signals and the random frequency interference signals can be effectively excluded by encoding the prior information and the motion characteristics of the detector.

[0117] In an alternative embodiment, the process of obtaining the target pulse echo combination can further include:

[0118] If there are three or more echo signals in the candidate pulse echo combination that are the same as the echo signals in the real pulse echo combination, the candidate pulse echo combination is determined as the target pulse echo combination; the real pulse echo combination is composed of the pulse echoes corresponding to the target to be hit.

[0119] Without loss of generality, it is assumed that the laser target indicator and the target to be hit are stationary, and the detector flies to the target to be hit at a speed of 2 Mach. As shown in the case of Figure 5 , of the 24 combination modes at this time, [1, 3, 5, 8] TThe combination is a combination of real target echoes, which meets the characteristics of the Mach target moving at a uniform speed to the detector 2, and obviously[1,3,6,9] T The combination does not meet the motion characteristics, and can be directly marked as an interference combination.

[0120] [1,3,5,7] T The combination meets the characteristics of three guide echoes received by four pulses, and at this time it is considered that[1,3,5,7] T The combination is also a sequence of captured target echoes, and[1,3,5,8] T The combination is[1,3,5,7] T The combination is sent to the next level as a possible target echo sequence, and if it fails to capture, the starting analysis pulse is adjusted to the l+1th pulse, and the next round of target capture is continued.

[0121] S130: Determine the position of the target to be hit according to the target pulse echo combination.

[0122] Specifically, the target pulse echo combination contains the real echo signal of the target to be hit, and the embodiments of the present application can accurately determine the position of the target to be hit according to the target pulse echo combination.

[0123] The present application realizes the following processes: ①a random repetition frequency waveform is proposed, ②an adaptive overlapping gate is proposed, ③a target capture and tracking method is designed using the prior motion information of the laser target indicator, the target and the detector, which can effectively investigate fixed / random high repetition frequency interference, and ④an end-to-end anti-repetition frequency interference solution is formed.

[0124] The specific descriptions are as follows:

[0125] 1. The pulse signal emitted by the laser target indicator to the target to be hit is a random repetition frequency signal, and after emission, the emission time is synchronized to the information processing module of the detector to assist the generation of the adaptive overlapping gate.

[0126] 2. Adaptive overlapping gate generation method: after obtaining the accurate time of the transmitted signal, all received signals within the previous gate are obtained in real time, and the received overlapping gate for the next pulse echo signal is generated based on this. The upper bound of the next pulse receiving gate is determined by the first pulse appearing in the gate, and the lower bound of the next pulse receiving gate is determined by the last pulse. Signals within the possible range of guide signals are considered.

[0127] 3. Signal decision based on prior information: the motion properties of the detector are calculated in real time through the pulse echo delay through the motion model, and the calculation results are compared with the real motion properties, which effectively filters out interference signals that cannot provide reasonable motion properties and improves the anti-high repetition frequency interference performance of the algorithm.

[0128] 4. The existing anti-interference method is mainly for fixed frequency interference signals, and cannot adapt to random frequency interference signals.

[0129] Compared with the prior art, the beneficial effects of the embodiments of the present application at least include the following:

[0130] 1. According to the coding rule of the transmitted pulse, the embodiments of the present application design an adaptive overlapping wave gate of the received pulse, comprehensively consider all pulses, and use the prior information of the detector motion to make a reasonable decision on the received signal of the adaptive overlapping wave gate. The conventional single pulse locking technology in the existing anti-interference technology only takes one pulse as the guidance signal echo in each wave gate, which is easy to cause locking error and loss of the real guidance signal. The embodiments of the present application generate overlapping wave gates, and consider all possible pulses, without simply discarding any echo pulse signal.

[0131] 2. High utilization rate of prior information: the prior information of the seeker motion is not used in the prior art, and the embodiments of the present application consider the prior information and filter out the pulse combination extracted in the previous step.

[0132] 3. The embodiments of the present application combine the advantages of the current mainstream anti-high frequency interference method, and add anti-interference operations in the laser target indicator part and the seeker signal processing part, as auxiliary to the coding of the transmitted laser pulse, and set overlapping wave gates and interference signal filtering algorithms in the signal processing part of the laser seeker, which has good application effect in the high frequency interference scene.

[0133] 4. The existing anti-interference method is mainly for fixed frequency interference signals, and cannot adapt to random frequency interference signals. The embodiments of the present application have excellent performance in both fixed frequency interference environment and random frequency interference environment.

[0134] Next, the application process of the present application will be described with specific examples, please continue to refer to Figure 6 .

[0135] 1. Determine the starting analysis time, after receiving the echo signal, the embodiments of the present application determine to start analysis from the first pulse according to the time synchronization relationship between the laser detector and the laser target indicator.

[0136] 2. According to the transmitted pulse prior information and the received echo signal, the overlapping wave gates of the first pulse to the l+3th pulse are adaptively generated, and the echo combination of the received signal pulses in the four overlapping wave gates is obtained.

[0137] 3. Based on prior information, the pulse combination is judged, each pulse combination can calculate the target distance corresponding to each pulse echo through the corresponding transmitting pulse transmitting time and the pulse interval relationship, the motion attribute corresponding to the pulse sequence is calculated through the distance and the established motion model, the calculated motion attribute is compared with the motion attribute of the real seeker, if the difference is less than the threshold value, it is considered that the pulse is a reasonable combination.

[0138] 4. Capture target: the laser target indicator has a certain missing rate, the detector has a certain detection rate, and the existence of high repetition frequency interference causes the probability of simultaneously obtaining multiple echo combinations.

[0139] Reference Figure 7 The embodiment of the application provides a high repetition frequency interference resisting device of a laser guidance radar, which comprises:

[0140] A first unit is configured to receive a plurality of echo signals and set a plurality of self-adaptive overlapping gates in real time according to the plurality of echo signals; the echo signal is a signal formed after a pulse signal transmitted by a laser target indicator in a random repetition frequency mode is reflected;

[0141] A second unit is configured to obtain a plurality of candidate pulse echo combinations from the plurality of echo signals according to the plurality of gates;

[0142] A third unit is configured to obtain a target pulse echo combination from the plurality of candidate pulse echo combinations according to the target distance of each echo signal and a target to be hit and the motion attribute of a seeker for hitting the target to be hit;

[0143] A fourth unit is configured to determine the position of the target to be hit according to the target pulse echo combination.

[0144] The embodiment of the application provides another high repetition frequency interference resisting device of a laser guidance radar, which comprises:

[0145] A fifth unit is configured to transmit a pulse signal in a random repetition frequency mode;

[0146] The period of the pulse signal is T=[T1, T2, T3...T K-1 ] T The superscript T represents vector transposition, T k is the repetition period of the k-1th and kth pulse signals, and T min <T k <T max , T min and T max are the minimum period and the maximum period of the signal transmitted by the laser target indicator, T lifeeffective transmission time of the pulse signal.

[0147] Embodiments of the present application also disclose a computer program product or computer program, which comprises computer instructions stored in a computer readable storage medium. A processor of a computer device can read the computer instructions from the computer readable storage medium, and the processor executes the computer instructions to enable the computer device to perform the method as shown in the embodiments. Figure 4 the method as shown in the embodiments.

[0148] In some alternative embodiments, the functions / operations mentioned in the block diagrams can not occur in the order mentioned in the operation diagrams. For example, two blocks shown in succession can actually be executed substantially concurrently or the blocks can sometimes be executed in reverse order, depending on the functionality / operations involved. Also, the embodiments presented and described in the flow diagrams are only examples. The flow diagrams are provided to offer an overall understanding of the method disclosed. The disclosed method is not limited to the operations and logical sequences presented in the flow diagrams. Alternative embodiments are contemplated, in which the order of various operations is changed and in which sub-operations described as part of a larger operation are independently executed.

[0149] Furthermore, although the present application is described in the context of functional modules, it is to be understood that one or more of the functions and / or features described can be integrated in a single physical device and / or software module, or one or more functions and / or features can be implemented in separate physical devices or software modules. It is also to be understood that detailed discussion of the actual implementation of each module is unnecessary to an understanding of the present application. Rather, the actual implementation is within the routine of an engineer's knowledge given the property, functionality and internal relationships of the various functional modules disclosed in the devices herein. Therefore, the present application is not limited to the specific details of the embodiments described herein, but is encompassed by the appended claims as well as their equivalents. In particular, it is contemplated that in light of the disclosure herein, those skilled in the art will be able to implement the present application without undue experimentation.

[0150] If the functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application or the parts of the technical solutions that essentially contribute to the prior art or the parts of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in the various embodiments of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0151] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered a list of executable instructions for implementing logic functions, and can be specifically embodied in any computer-readable medium for use by an instruction execution system, apparatus, or device, such as a computer-based system, a system including a processor, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or in conjunction with these instructions execution systems, apparatuses, or devices. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport programs for use by an instruction execution system, apparatus, or device, or in conjunction with these instruction execution systems, apparatuses, or devices.

[0152] More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection having one or more wires (electrical devices), a portable computer diskette (magnetic devices), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). In addition, the computer-readable medium can even be paper or other suitable medium on which the program can be printed, as the program can be electronically obtained, for example, by optical scanning of the paper or other medium, followed by editing, interpreting, or otherwise processing, if necessary, in other suitable ways to be electronically obtained, and then stored in the computer memory.

[0153] It should be understood that aspects of the application can be implemented in hardware, software, firmware or a combination thereof. In the above embodiments, various steps or methods can be implemented in software or firmware which is stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, and in another embodiment, any of the following technologies, known in the art, can be used: a combination of discrete logic circuits having logic gates for implementing logic functions upon an application of data signals, application specific integrated circuits having logic gates, field programmable gate arrays (FPGA), or other components, in combination or as the case can be.

[0154] In the description of the present specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0155] Although embodiments of the present application have been shown and described, it would be appreciated by those skilled in the art that changes, modifications, alternatives and variations to these embodiments could be made without departing from the principles and spirit of the application, the scope of which is defined by the claims and their equivalents.

[0156] The above is a specific description of the preferred embodiments of the present application, but the present application is not limited to the described embodiments, and those skilled in the art can make various equivalent modifications or replacements without departing from the spirit of the present application, and these equivalent modifications or replacements are included in the scope defined by the claims of the present application.

Claims

1. A method for resisting high repetition rate interference in laser-guided radar, characterized in that, include: The system receives multiple echo signals and sets multiple adaptive overlapping gates in real time based on the multiple echo signals; the echo signals are signals formed after reflection of pulse signals emitted by a laser target designator in a random repetition frequency manner. Multiple candidate pulse-echo combinations are obtained from multiple echo signals based on multiple gates; Based on the target distance between each echo signal and the target to be hit, and the motion properties of the seeker head used to hit the target to be hit, a target pulse echo combination is obtained from a plurality of candidate pulse echo combinations. The location of the target to be hit is determined based on the target pulse echo combination; The process of receiving multiple echo signals and setting multiple adaptive overlapping gates in real time based on the multiple echo signals includes: The four echo signals are received sequentially in chronological order. The gates that receive the four echo signals are respectively the first gate, the second gate, the third gate, and the fourth gate; the time when the first gate receives the first signal of the corresponding echo signal is taken as the opening time of the first gate, and the time when the first gate receives the last signal of the corresponding echo signal is taken as the closing time of the first gate. The opening and closing times of the second gate, the third gate, and the fourth gate are determined based on the first and last signal times received in the corresponding preceding gate. The step of determining the opening and closing times of the second gate, the third gate, and the fourth gate based on the first and last signal times received in the corresponding preceding gate includes: The opening and closing times of the second gate, the third gate, and the fourth gate are determined according to the gate setting expression. The gate setting expression is as follows: in, and These are the current opening and closing times of the gate, respectively. It is the gate width. and These are the times of the first and last signals received by the previous gate, respectively. and These represent the transmission time of the pulse signal corresponding to the echo received by the current gate and the pulse period of the pulse signal corresponding to the echo received by the previous gate, respectively. The step of obtaining multiple candidate pulse-echo combinations from multiple echo signals based on multiple gates includes: A valid echo signal from the target to be hit is received through the first gate; Several echo signals are received through the second gate, several echo signals are received through the third gate, and several echo signals are received through the fourth gate. Each time, an echo signal is selected from the first gate to the fourth gate in sequence to obtain multiple candidate pulse echo combinations. The step of obtaining a target pulse echo combination from multiple candidate pulse echo combinations based on the target distance between each echo signal and the target to be hit, and the motion properties of the seeker head used to hit the target to be hit, includes: Based on the transmission time of the pulse signal corresponding to each pulse echo combination and the delay relationship between the pulse signals, the target distance between each echo signal and the target to be hit is determined; Based on each target distance and a pre-established motion model, multiple first motion attributes of the pulse signal corresponding to the echo signal are obtained; Compare each of the first motion attributes with the second motion attributes of the seeker head; If the difference obtained from the comparison is less than a preset threshold, then the pulse echo combination corresponding to the first motion attribute is determined as the target pulse signal combination.

2. The method for resisting high repetition rate interference of laser-guided radar according to claim 1, characterized in that, The method further includes: If three or more echo signals in the candidate pulse echo combination are the same as the echo signals in the real pulse echo combination, then the candidate pulse echo combination is determined as the target pulse echo combination; the real pulse echo combination is composed of the pulse echoes corresponding to the target to be targeted.

3. A method for resisting high repetition rate interference in laser-guided radar, characterized in that, The method for resisting high repetition rate interference in a laser-guided radar as described in claim 1 includes: Transmit pulse signals in a random repetition mode; Wherein, the period of the pulse signal is T =[ T 1, T 2, T 3… T K-1 ] T superscript This represents the transpose of a vector. For the first and the The repetition period of each pulse signal, and , and These are the minimum and maximum periods of the signal emitted by the laser target designator, respectively. , The effective transmission time of the pulse signal is denoted as .

4. The method for resisting high repetition rate interference of a laser-guided radar according to claim 3, characterized in that, The method of transmitting pulse signals in a random repetition frequency manner includes: Pulse signals are transmitted in a random repetition manner according to the waveform transmission expression; The waveform transmission expression is: in, , This is indicated as set to the first The transmission delay time of each pulse signal relative to the 0th pulse signal, with the transmission time of the 0th pulse signal as the starting time. , m indicates that the pulse signal is the m-th transmitted pulse signal. This represents the repetition period from the (m-1)th pulse signal to the mth pulse signal; This is the waveform of the transmitted pulse signal.

5. A high repetition rate interference resistance device for laser-guided radar, characterized in that, The method for resisting high repetition rate interference in a laser-guided radar as described in claim 1 includes: The first unit is used to receive multiple echo signals and set multiple adaptive overlapping gates in real time according to the multiple echo signals; the echo signals are signals formed after reflection of pulse signals emitted by the laser target designator in a random repetition frequency manner; The second unit is used to obtain multiple candidate pulse echo combinations from multiple echo signals based on multiple gates; The third unit is used to obtain a target pulse echo combination from a plurality of candidate pulse echo combinations based on the target distance between each echo signal and the target to be hit, and the motion properties of the seeker head used to hit the target to be hit. The fourth unit is used to determine the position of the target to be hit based on the target pulse echo combination.

6. A high repetition rate interference resistance device for laser-guided radar, characterized in that, An anti-high repetition rate interference device for a laser-guided radar as described in claim 5, comprising: The fifth unit is used to transmit pulse signals in a random repetition frequency manner; Wherein, the period of the pulse signal is T =[ T 1, T 2, T 3… T K-1 ] T superscript This represents the transpose of a vector. For the first and the The repetition period of each pulse signal, and , and These are the minimum and maximum periods of the signal emitted by the laser target designator, respectively. , The effective transmission time of the pulse signal is denoted as .

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