A method for predicting deception jamming against pulse system code phase modulation fuze

Abstract

The application provides a prediction type deception jamming method for a pulse system code phase modulation fuze; pseudo-random m sequence samples of a code fuze signal are obtained through reconnaissance, a pseudo-random m sequence model is predicted based on the samples, an interference m sequence with a phase ahead of a target echo is generated, a prediction type deception jamming signal is generated through time domain, frequency domain, modulation domain and power domain composite modulation, the jamming signal is coherent with the target echo and can enter a range gate of the code fuze, so that the code fuze is mistaken as detecting a real target and is started in advance. Meanwhile, the interference effect of the jamming signal is simulated, and the simulation result shows that the phase leading / lagging interference effect can be realized through fuze cross-correlation processing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic countermeasures, and particularly relates to a prediction type deception jamming method for counteracting pulse system pseudo code phase modulation fuze. BACKGROUND

[0002] The pulse system pseudo code phase modulation fuze (referred to as pseudo code fuze) is a radio fuze using narrow pulse amplitude modulation, inter-pulse pseudo random code 0 / π phase modulation, and Doppler principle. The fuze uses narrow pulse sampling, range gate gating and pseudo random code correlation detection technology, and the complex envelope modulation function of the modulation signal is approximately "nail" type, and the distance resolution is high. From the code element width to the end of the pulse period, the autocorrelation output amplitude is close to zero, and the distance characteristic has absolute cutoff. The pseudo code fuze interference includes suppression interference and deception interference. The suppression interference adopts noise jamming technology, measures the frequency of the pseudo code fuze signal, obtains the frequency of the pseudo code fuze signal, and then autonomously generates narrowband aiming jamming, wideband blocking jamming, sweep jamming and the like. The noise jamming cannot obtain the correlation processing gain of the pseudo code fuze, and the jamming effect is poor. The deception jamming obtains a pseudo random code sequence in a period through reconnaissance, sequentially delays the pseudo random code sequence by a period of time according to a certain rule, and then continuously sends the pseudo random code sequence for several periods to the modulation and transmission circuit. In this way, the deception jamming has a certain effect on the continuous wave pseudo code phase modulation fuze, but cannot counteract the pulse system pseudo code phase modulation fuze with good distance cutoff characteristics. Here, the pseudo code fuze and the pseudo random code sequence are different. The pseudo code fuze is a fuze system, and the pseudo random code sequence is a periodic binary code string used for modulation of the pseudo code fuze signal and having sharp cutoff characteristics. SUMMARY

[0003] The present application provides a prediction type deception jamming method for counteracting the pulse system pseudo code phase modulation fuze, and the method comprises the following steps:

[0004] To achieve the above object, the present application adopts the following technical scheme:

[0005] A prediction type deception jamming method for counteracting the pulse system pseudo code phase modulation fuze, comprising the following steps:

[0006] S1: The interference machine receiving antenna transmits the received pseudo code fuze signal to the receiving front end, and outputs the pseudo code fuze signal to the receiving channel through the coupler;

[0007] S2: obtaining an analog intermediate frequency signal after down-conversion, filtering and amplification of the pseudo-code fuze signal in the receiving channel;

[0008] S3: AD sampling of the analog intermediate frequency signal by the DRFM to obtain a pseudo-code modulation sequence sample, and then predicting a pseudo-code sequence model based on the sample to obtain a pseudo-code fuze modulation m sequence;

[0009] S4: in a pseudo-code fuze modulation m sequence period, the interference controller controls the DRFM to perform predictive deception jamming signal complex modulation to generate a deception jamming signal sample with a phase ahead of the pseudo-code fuze signal, and then the DRFM generates an analog intermediate frequency jamming signal after DA conversion of the generated deception jamming signal sample, and outputs the analog intermediate frequency jamming signal to the transmitting channel;

[0010] S5: obtaining a radio frequency jamming signal after up-conversion, filtering and amplification of the analog intermediate frequency jamming signal in the transmitting channel, and outputting the radio frequency jamming signal to the jammer transmitting antenna after power amplification by the power amplifier to interfere with the pseudo-code fuze.

[0011] Further, in step S3, the specific content of predicting the pseudo-code sequence model based on the pseudo-code modulation sequence sample to obtain the pseudo-code fuze modulation m sequence is:

[0012] First, the concept of pseudo-random m sequence is introduced, which is a string of binary codes used for modulation of the pseudo-code fuze signal; the recursive equation of the complete pseudo-random m sequence corresponding to the pseudo-code fuze signal is written in the form of a matrix as follows:

[0013]

[0014] In the formula, the pseudo-random m sequence is generated by an n-stage feedback shift register, a i represents the state of each stage of the feedback shift register, and i = 1 ~ (2 n -2); c j represents the connection state of the feedback line, and j = 1 ~ n;

[0015] c j The solution of c j satisfies all equations at the same time, so there is a unique solution; since the pseudo-random m sequence has periodicity, AD sampling of the analog intermediate frequency signal by the DRFM obtains continuous (2n+1) code elements, i.e. the pseudo-code modulation sequence sample, and the entire code element sequence can be reconstructed through the sample; i.e. formula (1) is simplified as:

[0016]

[0017] Solving formula (2) can obtain parameters c1, c2……cn.n The value of is due to the fact that the pseudo-random m-sequence is generated by an n-stage feedback shift register, and the parameter c j The value of c1, c2...c determines the connection structure of the feedback shift register. Therefore, when c1, c2...c...c n After obtaining the value, the complete pseudo-random m-sequence can be reconstructed, thus obtaining the pseudo-code fuze modulation m-sequence.

[0018] Furthermore, in step S3, the reconstructed pseudo-code fuse modulation m-sequence is verified by using the pseudo-code modulation m-sequence obtained through reconnaissance.

[0019] Further, in step S4, the interference controller controls the DRFM to perform predictive deception interference signal composite modulation, generating a deception interference signal sample whose phase leads the pseudo-code fuze signal. The specific content of this sample is as follows:

[0020] Let the pseudo-code fuse modulation m-sequence in step S3 be x(t). Since the periodic pseudo-code fuse modulation m-sequence has a phase lead-lag relationship, and the time resolution of the lead or lag is a symbol width τ0, the interference controller can determine the number of symbol bits k that the pseudo-code fuse modulation m-sequence x(t) needs to be shifted according to the symbol width. i Then, based on the current symbol position, calculate the new shifted sequence x(t+k). i τ0), the new sequence is the deception interference signal sample.

[0021] Furthermore, the number of code bits k i The calculation is determined to be related to the target distance R and the miss distance ρ of the pseudo-code fuse, and the relationship between them is as follows:

[0022]

[0023] k can be calculated i :

[0024]

[0025] In the formula, c represents the speed of light.

[0026] Furthermore, in the time domain, in order for the jamming signal emitted by the jammer's transmitting antenna to enter the range gate of the pseudo-code fuze, the jamming signal needs to be continuously transmitted for a period of time T. r T r And the distance R between the projectile and the target, and the relative velocity v between the projectile and the target r Regarding this, let t be the time required for the pseudo-code fuse signal to reach the jammer. f , t f =R / v r Then T r =(1~2)tf .

[0027] Further, in frequency domain, the frequency measurement receiver detects the carrier frequency of the PN coded fuze signal, guides the frequency of the local oscillator signal, and makes the carrier frequency of the jamming signal align with the carrier frequency of the PN coded fuze signal through up-conversion and down-conversion.

[0028] Further, the output power P of the jamming signal emitted by the jamming machine is controlled j so that the power of the jamming signal received by the PN coded fuze is higher than the power of the target echo signal by (3-5) dB.

[0029] The present application has the following advantages:

[0030] 1. The model of the pseudo-random m sequence is predicted according to the PN coded modulation sequence sample obtained through detection, a deceptive false target jamming signal with a phase ahead of the real target is generated through modulation, the jamming signal is coherent with the PN coded fuze signal, and the correlation processing gain of the PN coded fuze can be obtained.

[0031] 2. The jamming duration is adjusted according to the missile-target distance, the jamming signal is generated during the pulse duration of the detected signal, and the jamming signal enters the range gate of the PN coded fuze.

[0032] 3. After the jamming signal lasts for a period of time, the jamming machine opens the window for detection and updates the jamming signal sample in a predictive manner, and the real-time performance is good.

[0033] 4. The power of the jamming signal is controllable, and the jamming signal power with the target echo amplitude characteristics of the PN coded fuze can be generated. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a block diagram of the existing pulse system PN coded phase modulation fuze system.

[0035] Figure 2 is a block diagram of the pulse system PN coded phase modulation fuze predictive deception jamming system designed by the present application.

[0036] Figure 3 is a flowchart of the pulse system PN coded phase modulation fuze predictive deception jamming system of the present application.

[0037] Figure 4 is a schematic diagram of the principle of generating a pseudo-random m sequence by an n-stage feedback shift register.

[0038] Figure 5 is a schematic diagram of the modulation process of the jamming signal for deception.

[0039] Figure 6 is an experimental schematic diagram of the autocorrelation output result of the PN coded sequence in the embodiment of the present application.

[0040] Figure 7This is an experimental schematic diagram of the correlation output results of the phase-leading / lagging pseudo-random m-sequence in an embodiment of the present invention.

[0041] Figure 8 This is an experimental schematic diagram of the correlation output results of the interference sequence in an embodiment of the present invention. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0043] The overall technical solution of this application is as follows:

[0044] 1. Working principle of pulse-based pseudo-code phase modulation fuze

[0045] Note: This section introduces the working principle of the fuze. The interference modulation technology described later is designed based on this fuze working principle.

[0046] The basic block diagram of a pseudo-random code 0 / π phase modulation fuze is as follows: Figure 1 As shown, it consists of a timing circuit module, a transmitting circuit module, a receiving circuit module, a signal processing circuit module, a fuze execution stage circuit, and a power supply circuit. The timing circuit module comprises a clock generator, a modulation pulse A generator, a range gated pulse B generator, a pseudo-code pulse C generator, and a correlation reference code D pulse delay unit. The transmitting circuit module consists of an RF oscillator, a directional coupler, an 0 / π phase modulator, a pulse modulator, a power amplifier, and a transmitting antenna. The transmitting circuit module transmits an RF pulse signal, phase-modulated by pseudo-random code 0 / π and sampled by periodic pulses, into a predetermined space. The receiving circuit module consists of a receiving antenna, a range gated circuit, a mixer, and a video amplifier. After being gated by the range wave, the RF signal is output by a zero-IF mixer as a pseudo-code bipolar video pulse sequence modulated by the Doppler frequency. The signal processing circuit module consists of a pseudo-random code correlator and signal processing circuitry, performing time-frequency domain processing such as pseudo-code correlation demodulation and Doppler signal detection to obtain target characteristic information and outputting a fuze activation pulse during missile-target encounter.

[0047] Specifically: the radio frequency oscillator outputs a stable sinusoidal voltage U CW (t), output via a directional coupler to the 0 / π phase modulator. The 0 / π phase modulator, under the control of a pseudo-random code A pulse, performs 0 / π binary phase modulation on the radio frequency signal. The modulated signal is output to a pulse modulator, sampled by the A pulse, and then amplified by a microwave power amplifier before being radiated into the predetermined space by the transmitting antenna. The partial echo signal U reflected by the target... R(t) The signal received by the receiving antenna, which is gated by the range gate B, is output to the mixer to mix and output an intermediate frequency signal U C (t) The signal received by the receiving antenna, which is gated by the range gate B, is output to the mixer to mix and output an intermediate frequency signal U D (t) The signal received by the receiving antenna, which is gated by the range gate B, is output to the mixer to mix and output an intermediate frequency signal U

[0048] The mathematical model of the random phase code phase modulation fuze transmitting signal can be expressed as:

[0049]

[0050] In formula (1), A T is the amplitude of the transmitting signal; is the complex envelope thereof; is the phase modulation function; f0 is the carrier frequency; and a(t) is the amplitude modulation function. For binary phase coding, It can also be expressed as a binary sequence

[0051] In the formula, u(t) is a pseudo-random code sequence, and its expression is:

[0052]

[0053] In the formula, N is the length of the pseudo-code sequence; T c is the symbol width; c i is a binary sequence, c i = {-1, 1};

[0054]

[0055] A phase coded signal is generated by modulating the phase of a carrier signal with a certain code sequence. The modulation code sequence is generally a pseudo-random code, which is a binary sequence that can be determined in advance and has a periodicity, and has good autocorrelation properties close to a binary random sequence. The m sequence generation principle is simple and the sequence length is not limited, and has good autocorrelation characteristics, and is widely used in pseudo-code fuzes.

[0056] The echo signal is:

[0057]

[0058] In the formula, A R is the amplitude of the receiving signal; ω d is the Doppler frequency; and τd The delay time for the transmitted signal, τ d = 2(R-v r t) / c, where R is the distance between the fuze and the target, v r is the relative velocity between the fuze and the target, and c is the speed of light.

[0059] The output signal of the mixer:

[0060]

[0061] where A E is the amplitude of the mixed signal.

[0062] The output signal of the correlator:

[0063] U T (t) = R(τ-τ d )cosω d t (6)

[0064] where R(τ-τ d ) is the autocorrelation function of the pseudo-random code sequence; τ d is the pre-delay time of the local pseudo-random code sequence, and R(τ-τ d ) takes the maximum value when τ = τ d .

[0065] 2. A method for predicting and deceiving jamming of a pulse system pseudo-code phase modulation fuze

[0066] 2.1. Composition and principle of the predicting jamming system:

[0067] The composition block diagram of the predicting and deceiving jamming system of the pulse system pseudo-code phase modulation fuze designed in the application is shown in Figure 2 The system is composed of a pseudo-code fuze signal receiving channel, a jamming controller, a digital radio frequency memory (DRFM for short), and a jamming transmitting channel. The pseudo-code fuze signal receiving channel receives the pseudo-code fuze signal and performs down-conversion and amplification processing to obtain a pseudo-code modulated signal; the DRFM AD samples the analog intermediate frequency signal output by the receiving channel, detects the pseudo-code modulated signal, performs pseudo-code model prediction, and obtains a predicted pseudo-code signal; the jamming controller controls the DRFM to perform complex modulation of the predicted and deceiving jamming signal in a pseudo-code modulated signal sampling period according to the starting condition of the pseudo-code fuze, generates a deceiving jamming signal sample with a phase ahead of the pseudo-code fuze signal, and outputs the analog intermediate frequency signal through DA conversion; and the jamming transmitting channel outputs the analog intermediate frequency signal after up-conversion and power amplification.

[0068] The jamming controller controls the DRFM to complete the detection of the pseudo-code fuze signal and the jamming, and the work flow chart is as shown in Figure 3As shown, the jamming system first detects the pseudo-code fuse signal, obtains the pseudo-code sequence, predicts the complete pseudo-code fuse signal model based on this sequence, and then compares and verifies the predicted pseudo-code signal with the detected pseudo-code modulation signal. During a sampling period of the pseudo-code modulation signal, the predicted pseudo-code signal is subjected to interference composite modulation in the time domain, frequency domain, modulation domain, and power domain to generate a deceptive jamming signal. When the jamming time arrives, the deceptive jamming system performs windowed detection on the pseudo-code fuse signal and updates the deceptive jamming signal sample.

[0069] 2.2 Analysis and Recognition of Pseudo-random Code m-Sequence Model:

[0070] Note: This section introduces the pseudo-random code m-sequence model, and the prediction of the pseudo-code fuze signal is based on this pseudo-code m-sequence model;

[0071] Pseudo-random codes typically use pseudo-random m-sequences, whose sequence structure exhibits random characteristics but can be predetermined and repeatedly generated and replicated, possessing excellent autocorrelation functions. They are generated by linear shift registers with feedback; linear feedback shift registers of the same order can generate m-sequences with the longest period, P = 2. r -1 (r is the number of stages in the feedback shift register);

[0072] An m-sequence composed of n-stage feedback shift registers is produced by the generator, such as... Figure 4 As shown, in Figure 4 a i Indicates the state of each feedback shift register, c j This indicates the connection status of the feedback line. An n-stage feedback shift register can generate a maximum period length of (2... n A sequence of m (-1). For any a i The recurrence relation for the m-sequence is as follows:

[0073]

[0074] In the formula, a i ∈{1,-1}, c j ∈{0,1}; in equation (7), the summation is performed modulo 2, c j The value of c determines the connection structure of the feedback shift register, according to the parameter c. j Reconstruct the entire m sequence;

[0075] The recurrence relation for the m-sequence can be written in matrix form as follows:

[0076]

[0077] c j Solving this problem is an overdetermined system of equations, due to the parameter c jIt satisfies all equations simultaneously, thus having a unique solution. Due to the continuity and periodicity of sampling, only (2n+1) consecutive code elements need to be sampled to reconstruct the entire code element sequence, and equation (8) can be expressed as:

[0078]

[0079] Solving this equation yields the structural parameters c1, c2, ..., c of the n-stage feedback shift register. n Thus reconstructing all (2 n -1) code elements.

[0080] 2.3 Predictive deception jamming composite modulation technology:

[0081] Suppose that an n-stage feedback shift register forms an m-sequence x(t), and the period of this m-sequence is N chips, then N = 2. n -1; and:

[0082] x(t)=x(t+NT c (10)

[0083] Periodic m-sequences exhibit a phase lead / lag relationship, with the time resolution of the lead / lag being one symbol width τ0. Let the reference m-sequence be x(t), and the lead and lag amounts be k1 and k2, respectively. Then the lead m-sequence x... p (t)=x(t+k1τ0), lagged m-sequence x l (t)=x(t-k2τ0).

[0084] Based on relative position t i Calculate the number of code bits k that need to be shifted for sequence m. i (k i ≠0), that is, from the current m-sequence x(t), calculate the new sequence x(t+k) after shifting. i τ0). When k i When >0, the kth symbol after the current symbol i The sequence starting with k symbols is used as the forwarding sequence (interference sequence); when k i <0, the kth symbol preceding the current symbol i The sequence starting with a symbol is used as the forwarding sequence (interference sequence).

[0085] Predicted sequence parameter k i The distance R between the jammer and the fuze, and the miss distance ρ of the fuze, are related, and the relationship is as follows:

[0086]

[0087] Calculation yields:

[0088]

[0089] In the formula, k i With a period of N, it can be represented as k i =lN+k' i ,in,

[0090] In summary, the predictive spoofing jamming sequence modulation process is as follows: Figure 5 As shown. The jammer detects and acquires the sampling sequence within the sampling time τ, predicts the pseudo-random code based on the m-sequence model, and generates an interference sequence (deceiving interference signal samples) 1 to n. The jamming continues for a period T. r Afterwards, the pseudocode sequence is resampled and predicted to update the interference signal samples.

[0091] The jamming controller performs composite jamming modulation on the detected signal in the time, frequency, modulation, and power domains. In the frequency domain, the carrier frequency of the detected pseudo-code fuze signal is aligned with that of the deception jamming signal. In the modulation domain, the carrier frequency of the predicted pseudo-code signal is subjected to 0 / π binary phase modulation to obtain an jamming sequence whose phase leads the pseudo-code fuze signal. In the time domain, the jamming signal is continuously transmitted for a period of time T to allow it to enter the range gate of the fuze. r T r It is related to the target distance R, T r And the distance R between the projectile and the target, and the relative velocity v between the projectile and the target r Regarding this, let t be the time required for the pseudo-code fuse signal to reach the jammer. f , t f =R / v r Then T r =(1~2)t f After a period of interference, the prediction is resampled and the deception interference signal sample is updated; in the power domain, the output power of the interference signal is controlled so that the power of the interference signal received by the fuze is (3~5) dB higher than that of the target echo signal.

[0092] 3. Interference simulation results and analysis

[0093] Taking a 31-bit pseudo-random m-sequence 0 / π phase-modulated fuze as an example, a simulation study of predictive deception jamming modulation technology is conducted.

[0094] Let m sequence C k =[1 -1 1 1 -1 1 -1 1 -1 -1 1 1 1 1 -1 -1 -1 1 1 -1 -1 -1 -1 -1 1 -1 -1 -1 1 -1 1 1], when the phase of the m-sequence received by the fuze is consistent with the phase delay sequence of the fuze pseudo-random code, the m-sequence outputs its maximum value, such as Figure 6 As shown.

[0095] The time resolution of phase lead / lag is one symbol width τ0, and there are two false targets, one false target leading the real target by 10τ0, and the other false target lagging the real target by 5τ0, and the output results of the pseudo-code fuze correlation processing are as shown in the figure. Figure 7 As shown in the figure, the interference sequence leads / lags the target echo, and the cross-correlation output peak value and the autocorrelation output peak value are different by 10τ0 and 5τ0, respectively.

[0096] Supposing τ0=100 ns, the projectile-target distance R=500 m, and the fuze miss distance ρ=10 m, the predicted sequence parameter k can be calculated by formula (12) as follows: i k = 33.The pseudo-code sequence period N=31, k' i = mod(k i ,N) = 2, the interference sequence needs to lead the real target by 2τ0, and the output results of the pseudo-code fuze autocorrelation processing are as shown in the figure. Figure 8 As shown in the figure, after the correlation processing, the interference sequence leads the target echo by 2τ0 in the time domain, so that the fuze cannot identify the false target. Figure 8

[0097] 4. Conclusion

[0098] The pulse system pseudo-code phase modulation fuze adopts the narrow pulse sampling, the distance gate gating and the pseudo-random code correlation detection technology, has a sharp distance cutoff characteristic, greatly improves the distance ambiguity, and has strong anti-interference ability. The application proposes a predicted deception jamming technology against the pulse system pseudo-code fuze, obtains the pseudo-random m sequence of the pseudo-code fuze through reconnaissance, predicts the pseudo-random code m sequence model, generates an interference m sequence leading the target echo in phase, and generates an interference signal through the interference composite modulation in the time domain, the frequency domain, the modulation domain and the power domain. The interference signal is coherent with the target echo, can enter the distance wave gate of the fuze, and makes the fuze mistakenly think that the real target is detected and starts early. The interference effect of the predicted pseudo-random m sequence is simulated, and the simulation results show that the phase lead / lag interference effect can be realized through the fuze cross-correlation processing.

[0099] The above are only preferred embodiments of the application, and the protection scope of the application is not limited to the above-mentioned embodiments. Any technical solution falling within the idea of the application belongs to the protection scope of the application. It should be noted that some improvements and decorations without departing from the principle of the application are considered as the protection scope of the application.

Claims

1. A predictive deception jamming method against pulse-based pseudo-code phase modulation fuses, characterized in that, Includes the following steps: S1: The jammer's receiving antenna transmits the received pseudo-code fuse signal to the receiving front end, and outputs it to the receiving channel via a coupler; S2: In the receiving channel, the pseudo-code fuze signal is down-converted and filtered and amplified to obtain an analog intermediate frequency signal; S3: DRFM performs AD sampling on the analog intermediate frequency signal to obtain pseudocode modulation sequence samples, and then predicts the pseudocode sequence model based on the samples to obtain the pseudocode fuze modulation m sequence. S4: Within one pseudo-code fuze modulation m-sequence period, the interference controller controls the DRFM to perform predictive deception interference signal composite modulation, generating a deception interference signal sample whose phase leads the pseudo-code fuze signal. Then, the DRFM converts the generated deception interference signal sample through a DA converter to generate an analog intermediate frequency interference signal, which is output to the transmission channel. The specific content of the interference controller controlling the DRFM to perform predictive deception interference signal composite modulation to generate a deception interference signal sample whose phase leads the pseudo-code fuze signal is as follows: Let the pseudocode fuze modulation sequence m in step S3 be... Because the periodic pseudocode fuze modulation m-sequence has a phase lead-lag relationship, and the time resolution of the lead or lag is one symbol width. Therefore, for the current pseudocode fuze modulation m-sequence The interference controller can determine the pseudo-code fuze modulation m-sequence based on the symbol width. Number of symbol bits to be moved Then, the new sequence after shifting is calculated based on the current symbol position. The new sequence is the deception interference signal sample; number of code bits The calculation determines the distance between the target and the target. Off-target magnitude of pseudo-code fuse The relationship between them is as follows: （3） Calculation yields : （4） In the formula, The meaning is the speed of light; S5: In the transmission channel, the analog intermediate frequency interference signal is up-converted and filtered and amplified to obtain the radio frequency interference signal. The power amplifier amplifies the radio frequency interference signal and outputs it to the jammer's transmitting antenna to interfere with the pseudo-code fuse.

2. The predictive deception jamming method against pulse-based pseudo-code phase modulation fuses according to claim 1, characterized in that, In step S3, the specific content of the pseudocode sequence model predicted based on the sample to obtain the pseudocode fuze modulation m sequence is as follows: First, we need to introduce the concept of a pseudo-random m-sequence, which is a string of binary codes used for modulation of the pseudo-code fuse signal. The recursive equation for the complete pseudo-random m-sequence corresponding to the pseudo-code fuse signal can be written as a matrix as follows: （1） In the formula, the pseudo-random m-sequence is composed of Generation of a multi-stage feedback shift register, This indicates the state of each feedback shift register, and ; This indicates the connection status of the feedback line, and ; Solving this problem is an overdetermined system of equations, due to the parameters It satisfies all equations simultaneously, therefore having a unique solution; since the pseudo-random m-sequence is periodic, continuous signals are obtained by performing AD sampling on the analog intermediate frequency signal using DRFM. Each symbol is obtained, that is, a sample of the pseudocode modulation sequence is obtained, and the entire symbol sequence can be reconstructed from this sample; that is, equation (1) is simplified to: （2） Solving formula (2) will yield the parameters. , ... The value, since the pseudo-random m-sequence is composed of Generated by a stage feedback shift register, and the parameters The value of determines The connection structure of the multi-stage feedback shift register, therefore, when obtaining , ... After obtaining the value, the complete pseudo-random m-sequence can be reconstructed, thus obtaining the pseudo-code fuze modulation m-sequence.

3. The predictive deception interference method for countering pulse-based pseudo-code phase modulation fuses according to claim 1, characterized in that, In step S3, the reconstructed pseudo-code fuse modulation m-sequence is verified by using the pseudo-code modulation m-sequence obtained through reconnaissance.

4. The predictive deception interference method for countering pulse-based pseudo-code phase modulation fuses according to claim 1, characterized in that, In the time domain, in order for the jamming signal emitted by the jammer's transmitting antenna to enter the range gate of the pseudo-code fuze, the jamming signal needs to be continuously transmitted for a period of time. , and the distance between the target and the target Relative velocity of projectile and target Regarding this, let the time required for the pseudo-code fuse signal to reach the jammer be... , ,but Equal to 1 to 2 times .

5. The predictive deception interference method for countering pulse-based pseudo-code phase modulation fuses according to claim 1, characterized in that, In the frequency domain, the frequency measurement receiver detects and obtains the carrier frequency of the pseudo-code fuze signal, guides the local oscillator signal frequency, and aligns the carrier frequency of the interference signal with the carrier frequency of the pseudo-code fuze signal through up-conversion and down-conversion.

6. The predictive deception jamming method against pulse-based pseudo-code phase-modulation fuses according to claim 1, characterized in that, Control the output power of the jamming signal emitted by the jammer's transmitting antenna. This makes the power of the interference signal received by the pseudo-code fuze 3 dB to 5 dB higher than the power of the target echo signal.

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