Comb spectrum sweep frequency noise interference generation method and device

Abstract

The invention belongs to the technical field of radio electronic countermeasure, and provides a comb spectrum sweep frequency noise interference generation method and device, and the method comprises the steps: determining the center frequency of each sub-band, and obtaining the center frequency of a sweep frequency noise sub-band according to the center frequency of each sub-band and a sweep frequency rule; the sweep frequency noise sub-band center frequency is used for controlling the multi-phase DDS module to generate a noise local oscillator digital signal; performing frequency mixing on the noise local oscillator digital signal and the baseband noise signal to obtain a noise intermediate frequency digital signal; when a start command is obtained, generating a noise intermediate-frequency analog signal according to the noise intermediate-frequency digital signal; and obtaining a comb spectrum sweep frequency noise radio frequency signal according to the noise intermediate frequency analog signal. According to the method provided by the invention, discreteness of the comb spectrum can cover different radar working frequency points of a plurality of frequency bands at the same time, the method adapts to multi-frequency-band interference or effective interference of a plurality of radars, and in combination with different frequency sweeping laws, the radar anti-interference difficulty is increased, and the radar anti-interference difficulty is not easy to eliminate.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radio electronic countermeasures, and particularly relates to a comb spectrum sweep noise jamming method and device. BACKGROUND

[0002] The blocking jamming is a wideband jamming for jamming multiple channels in a frequency band, and is divided into continuous blocking jamming and comb blocking jamming according to the frequency spectrum. In the blocking bandwidth, the continuous blocking jamming transmits the jamming signal in the whole frequency band, and suppresses the communication signal in the frequency band at the same time, and the frequency spectrum is uniformly distributed. The comb blocking jamming is that the jamming frequency band is in the form of comb, and only the communication signal falling into the jamming frequency band is jammed, and the jamming frequency band can be fixed or mobile. When the comb blocking jamming is used, the "comb teeth" must be overlapped with the frequency spectrum of the target signal. Therefore, the channel interval of the jammed signal needs to be known in advance by reconnaissance. If the channel interval is inconsistent with the interval of the adjacent "comb teeth", or the signal frequency spectrum cannot be overlapped with the "comb teeth", the continuous jamming should be used.

[0003] The sweep noise jamming is a combination of the aiming jamming and the blocking jamming, and refers to the jamming formed by the continuous variation of the jamming transmitter carrier frequency in a wide frequency band according to a certain speed, a certain bandwidth and a certain sweep order.

[0004] The jamming device periodically scans each channel in a certain frequency band, and suppressively jams all local electromagnetic signals in the frequency band. If the sweep speed is moderate, multiple electronic devices in the sweep range can be periodically subjected to strong jamming within a certain time, which is the most commonly used and effective jamming mode.

[0005] However, the traditional comb spectrum noise belongs to the blocking jamming, and a large power is needed to effectively jam the radar. The sweep noise jamming can effectively jam the radar without a large power, but the sweep noise jamming cannot simultaneously jam the radars in multiple frequency bands, and the jamming effect will also decrease when the jamming bandwidth is wide. SUMMARY

[0006] In view of the defects in the prior art, the present application provides a comb spectrum sweep noise jamming method and device to solve the problem that the low jamming power and the multi-frequency band jamming cannot be simultaneously realized at present.

[0007] In a first aspect, the present application provides a comb spectrum sweep noise jamming method, comprising: Determine each sub-band center frequency, according to the sub-band center frequency and the sweep frequency rule, obtain the sweep frequency noise sub-band center frequency; the sweep frequency noise sub-band center frequency is used for controlling the multi-phase DDS module to generate a noise local oscillator digital signal, the dwell time t is according to the sweep frequency rule, the sweep frequency period T, the sweep frequency bandwidth And the sweep frequency step Determination is made. Mix the noise local oscillator digital signal with the baseband noise signal to obtain a noise intermediate frequency digital signal. When the start command is obtained, a noise intermediate frequency analog signal is generated according to the noise intermediate frequency digital signal. According to the noise intermediate frequency analog signal, a comb spectrum sweep frequency noise radio frequency signal is obtained.

[0008] As can be seen from the above technical solution, the comb spectrum sweep frequency noise interference generation method provided by the application has the advantages that the interference energy is concentrated on discrete comb spectrum lines, the power consumption is lower than that of wideband noise interference, the radar interference efficiency is higher, the discreteness of the comb spectrum can cover different radar operating frequencies of multiple frequency bands at the same time, the effective interference of multiple radars or multiple radars is adapted, the radar anti-interference difficulty is increased by combining different sweep frequency rules, and the radar is not easy to eliminate.

[0009] Optionally, the sweep frequency rule includes sawtooth, triangle and sine.

[0010] Optionally, the minimum value of the sweep frequency noise sub-band center frequency , i represents the current count, i≤n, is the sub-band center frequency, is the sweep frequency bandwidth, is the minimum center frequency of the sweep frequency noise sub-band.

[0011] Optionally, when the sweep frequency rule is sawtooth or triangle, each sweep frequency noise sub-band center frequency , is the sweep frequency step, is the i-th sweep frequency noise sub-band center frequency; The sweep frequency number ; When the sweep frequency rule is sawtooth, the current count i starts from 0 and increases by 1 each time until it is equal to n, and then the count starts from 0 again, the dwell time ; When the sweep frequency rule is triangle, the current count i starts from 0 and increases by 1 each time until it is equal to n, and then starts to decrease by 1 each time until it is equal to 0, and then the count starts from 0 again and increases by 1, the dwell time .

[0012] Optionally, when the sweep frequency rule is sine, each sweep frequency noise sub-band center frequency , m is the number of r to meet the decimal of the sine law, T is the residence time, and T is the sweep cycle.

[0013] Optionally, for the equal-interval comb spectrum sweep noise, each of the sub-band center frequencies is determined according to a sub-band minimum center frequency; wherein the sub-band minimum center frequency is calculated by the following formula: , The sub-band minimum center frequency is fmin, The set center frequency is fset, The number of spectrum points is n≥2, The spectrum interval is f, and [·] represents the rounding operation; Then each sub-band center frequency is f , The sub-band center frequency is f, The current count is i≤n.

[0014] According to the above technical solution, the working frequency points of one radar or multiple radars within the time width can be covered, the spectrum interval is adjusted to ensure that the interference energy falls completely into the radar receiving channel, and energy waste is avoided.

[0015] Optionally, for the self-defined comb spectrum sweep noise, each sub-band center frequency is f , The set output radio frequency is fset, The local oscillator frequency is fLO.

[0016] According to the above technical solution, the self-defined comb spectrum sweep noise can be designed according to the frequency modulation mode or working frequency band of a specific radar, and the frequency domain anti-interference measures of the radar are destroyed.

[0017] In a second aspect, the application provides a comb spectrum sweep noise interference generation device for executing an embedded program to realize the method steps of any possible implementation manner of the first aspect.

[0018] By adopting the above technical solution, the present application has the following beneficial effects: The comb spectrum sweep noise interference generation method provided by the present application concentrates interference energy on discrete comb spectrum lines, has lower power consumption than wideband noise interference, and has higher radar interference efficiency; the discreteness of the comb spectrum can simultaneously cover different radar working frequency points of multiple frequency bands, adapt to effective interference of multiple radars or multiple frequency bands, increase the difficulty of radar anti-interference in combination with different sweep rules, and is not easy to be eliminated. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the drawings required to be used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual proportions.

[0020] Figure 1 A flow chart of a comb spectrum sweep noise interference generation method provided by an embodiment of the present application is shown; Figure 2 A time-frequency diagram of sweep noise with a sawtooth sweep rule provided by an embodiment of the present application is shown; Figure 3 A time-frequency diagram of sweep noise with a triangular sweep rule provided by an embodiment of the present application is shown; Figure 4 A time-frequency diagram of sweep noise with a sinusoidal sweep rule provided by an embodiment of the present application is shown; max is the highest frequency that can be covered by the sweep signal, min is the lowest frequency that can be covered by the sweep signal, and T is the sweep period. Figure 5 A structural block diagram of a comb spectrum sweep noise interference generation device provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0021] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0022] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present application should be understood as the usual meanings understood by the skilled person in the field to which the present application belongs.

[0023] Embodiment 1 As shown in Figure 1 , a comb spectrum sweep noise interference generation method is provided for generating equidistant comb spectrum sweep noise interference, comprising: S1. Determine the center frequency of each subband, and obtain the sweep noise subband center frequency according to the subband center frequency and the sweep rule. The sweep noise subband center frequency is used to control the multi-phase DDS module to generate a noise local oscillator digital signal, and the dwell time t is determined according to the sweep rule, the sweep period T, the sweep bandwidth and the sweep step .

[0024] First, the minimum center frequency of the sub-band is calculated according to the center frequency, the number of spectral points and the spectral interval. For the equal-interval comb spectrum sweep noise, the center frequency of each sub-band is determined according to the minimum center frequency of the sub-band; wherein the minimum center frequency of the sub-band is calculated by the following formula: (1) is the minimum center frequency of the sub-band, is the set center frequency, is the number of spectral points, n≥2, is the spectral interval, [·] represents the rounding operation; then the center frequency of each sub-band is (2) wherein, is the center frequency of the sub-band, is the current count, i≤n.

[0025] The generation of each sub-band signal of the comb spectrum sweep noise interference signal uses the generation mode of the sweep noise, mainly adopts the mode of combining various regular frequency modulation signals with narrowband noise, and the main parameters of the sweep noise include the center frequency, the sweep bandwidth, the sweep law, the sweep step and the sweep period.

[0026] The main generation process is: the center frequency of the sweep noise sub-band is calculated according to the center frequency, the sweep bandwidth, the sweep law and the sweep step, the dwell time of the sweep noise sub-band center frequency is determined by the sweep law, the sweep period, the sweep bandwidth and the sweep step, the sweep noise sub-band center frequency is used to control the multi-phase DDS module to generate the local oscillator digital signal, and then the local oscillator digital signal is mixed with the baseband noise signal to obtain the noise intermediate frequency signal. When receiving the start command of the main control module, the noise intermediate frequency digital signal is sent to the DAC driving module to realize digital-to-analog conversion and generate an analog intermediate frequency signal. The parameter solving method of each sweep law is as follows: As shown in Figure 2 , the time-frequency diagram of the sweep noise with sawtooth sweep law; for the sweep law of sawtooth, the specific calculation method of the sweep noise sub-band center frequency and the dwell time is as follows: Calculation of the minimum value of the sweep noise sub-band center frequency: (3) wherein, i represents the current count, i≤n, is the center frequency of the sub-band, is the sweep bandwidth, is the minimum center frequency of the sweep noise sub-band.

[0027] The i-th sweep noise sub-band center frequency (4) Sweeping frequency times (5) For the sweep step, For the i-th sweep noise sub-band center frequency.

[0028] For the sweep rule is sawtooth, the current count i starts from 0 and increases by 1 each time until it is equal to n, then it starts from 0 again, and the above process is repeated; the dwell time is (6) As shown in Figure 3 , the sweep noise time-frequency diagram of the sweep rule is triangular; the calculation method of the sweep noise sub-band center frequency is the same as formula (3) - formula (5).

[0029] For the sweep rule is triangular, unlike the sweep noise of the sweep rule is sawtooth, the current count i starts from 0 and increases by 1 each time until it is equal to n, then it starts to decrease by 1 each time until it is equal to 0, and then it starts from 0 again and increases by 1, and the above process is repeated; for the sweep rule is triangular, the dwell time is (7) As shown in Figure 4 , the sweep noise time-frequency diagram of the sweep rule is sinusoidal; for the sweep rule is sinusoidal, the specific calculation method of the sweep noise sub-band center frequency and the dwell time is as follows: Each sweep noise sub-band center frequency calculation: (8) In the formula, is a decimal that satisfies the sinusoidal rule, m is the number of r, t=T / m is the dwell time, and T is the sweep period. In practical applications, all values of r can be pre-stored in ROM, and then read out from the ROM every dwell time t.

[0030] The dwell time of each sweep noise sub-band center frequency is (9) S2. Mix the noise local oscillator digital signal and the baseband noise signal to obtain a noise intermediate frequency digital signal.

[0031] S3. When the start command is obtained, generate a noise intermediate frequency analog signal according to the noise intermediate frequency digital signal; S4. Obtain a comb spectrum sweep noise radio frequency signal according to the noise intermediate frequency analog signal.

[0032] The S1 acquires the frequency center of the frequency-sweeping noise subband, and the frequency center of the frequency-sweeping noise subband is used to control the multi-phase DDS module to generate the local oscillator digital signal, and then the local oscillator digital signal is mixed with the baseband noise signal to obtain the noise intermediate frequency signal. After receiving the start command of the main control module, the noise intermediate frequency digital signal is sent to the DAC driving module, and the DAC driving module drives the DAC chip to realize digital-to-analog conversion to generate an analog intermediate frequency signal.

[0033] Based on the comb spectrum frequency-sweeping noise interference generation method provided in the embodiment, the interference energy is concentrated on discrete comb spectrum lines, the power consumption is lower than that of wideband noise interference, and the radar interference efficiency is higher; the discreteness of the comb spectrum can cover different radar operating frequencies of multiple frequency bands at the same time, adapt to effective interference of multiple radar or multiple radars, increase the difficulty of radar anti-interference in combination with different frequency-sweeping rules, and is not easy to be eliminated.

[0034] Embodiment 2 A comb spectrum frequency-sweeping noise interference generation method is provided for generating a custom comb spectrum frequency-sweeping noise interference, comprising: S1. Determine the center frequency of each subband, and acquire the frequency center of the frequency-sweeping noise subband according to the center frequency of the subband and the frequency-sweeping rule; the frequency center of the frequency-sweeping noise subband is used to control the multi-phase DDS module to generate the noise local oscillator digital signal, the dwell time t is determined according to the frequency-sweeping rule, the frequency-sweeping period T, the frequency-sweeping bandwidth and the frequency-sweeping step .

[0035] The custom comb spectrum frequency-sweeping noise interference includes parameters such as center frequency 1, center frequency 2, …, center frequency n (≥16), the number of spectrum points, the frequency-sweeping period, the frequency-sweeping rule, the frequency-sweeping bandwidth, and the frequency-sweeping step.

[0036] According to the corresponding relationship between the microwave up-conversion intermediate frequency and the radio frequency, the center frequency 1, the center frequency 2, …, and the center frequency n (≥16) are converted into the intermediate frequency 1, the intermediate frequency 2, …, and the intermediate frequency n (≥16), and these intermediate frequencies are used as the center frequency of each subband, and the center frequency of each subband is used in turn from small to large, and the dwell time of the center frequency of each subband is the frequency-sweeping period, and the subband bandwidth is the frequency-sweeping bandwidth.

[0037] First, the center frequency of each subband is calculated, and for the custom comb spectrum frequency-sweeping noise, the center frequency of each subband is , is the set output radio frequency, is the local oscillator frequency.

[0038] The frequency-sweeping noise subband center frequency for generating each subband wide noise signal is calculated in combination with the frequency-sweeping rule. The generation method of the subband frequency-sweeping noise is the same as that of the equally spaced comb spectrum frequency-sweeping noise, and the As the center frequency of each sub-band, the sub-band sweep signal generates the remaining parameters required.

[0039] S2. Mix the noise local oscillator digital signal with the baseband noise signal to obtain a noise intermediate frequency digital signal.

[0040] S3. When the start command is obtained, generate a noise intermediate frequency analog signal according to the noise intermediate frequency digital signal.

[0041] S4. Obtain a comb spectrum sweep noise radio frequency signal according to the noise intermediate frequency analog signal.

[0042] When generating each sub-band sweep noise, the local oscillator control code for microwave up-conversion needs to be selected according to the corresponding center frequency, so as to generate noise signals in different frequency bands.

[0043] Embodiment 3 Figure 5 A comb spectrum sweep noise jamming device is shown, and the specific implementation process of the comb spectrum sweep noise jamming is as follows: a signal generation module receives control messages required for comb spectrum sweep noise jamming signal generation in real time; after receiving the control messages, the control messages are parsed to obtain parameters required for comb spectrum sweep noise jamming signal generation, then various parameters are related to the solution, and the frequency control word, the baseband noise parameter, and the local oscillator control code for controlling the microwave frequency conversion module required for signal generation are obtained.

[0044] The frequency control word controls the multi-phase DDS (Direct Digital Synthesis) module to generate a digital local oscillator signal as the local oscillator signal required for digital mixing, and then the baseband noise signal is superimposed on the local oscillator signal through digital mixing to obtain a noise intermediate frequency digital signal. According to the control command of the control module, if output is required, the noise intermediate frequency digital signal is sent to the DAC driving module (DAC, Digital-to-Analog Converter), the DAC chip converts the digital signal into an analog signal to obtain a noise intermediate frequency analog signal, and finally the intermediate frequency signal is sent to the microwave frequency conversion module to obtain the final comb spectrum sweep noise radio frequency signal.

[0045] The device provided in the embodiment has simple system design, small development difficulty, less hardware components, and low equipment cost.

[0046] The above embodiments are only used to introduce the technical solutions of the present application in detail, but the above embodiment descriptions are only used to help understand the method of the present embodiment, and should not be understood as a limitation of the present embodiment. Changes or replacements that can be easily thought of by those skilled in the art should be covered within the protection scope of the present embodiment.

Claims

1. A method for generating comb spectrum sweep noise interference, characterized in that: include: Determine the center frequency of each sub-band, and obtain the center frequency of the swept noise sub-band according to the sub-band center frequency and the sweep frequency rule; The center frequency of the swept noise sub-band is used to control the multi-phase DDS module to generate a noise local oscillator digital signal. The dwell time t is determined by the sweep rule, sweep period T, and sweep bandwidth. and frequency sweep step Sure; Mixing the noise local oscillator digital signal with the baseband noise signal to obtain a noise intermediate frequency digital signal; When a start command is obtained, a noise intermediate frequency analog signal is generated according to the noise intermediate frequency digital signal; A comb spectrum swept noise radio frequency signal is obtained according to the noise intermediate frequency analog signal.

2. The method according to claim 1, characterized in that The frequency sweeping patterns include sawtooth, triangle and sine.

3. The method according to claim 2, characterized in that Minimum center frequency of the swept noise subband , i represents the current count, i≤n, is the sub-band center frequency, is the sweep bandwidth, is the minimum center frequency of the swept noise subband.

4. The method according to claim 3, characterized in that When the frequency sweeping rule is sawtooth or triangle, the center frequency of each frequency sweeping noise subband is , For frequency sweep step, is the center frequency of the i-th swept noise subband; Frequency sweeps ; When the sweep frequency pattern is sawtooth, the current count i starts to increase from 0, and increases by 1 each time until it equals n, and then starts to count from 0 again. The dwell time ; When the frequency sweep pattern is triangular, the current count i starts to increase from 0, and increases by 1 each time until it equals n, then starts to decrease, and decreases by 1 each time until it equals 0, and then starts to count and increase from 0 again. The dwell time .

5. The method according to claim 3, characterized in that When the frequency sweeping rule is sinusoidal, the center frequency of each frequency sweeping noise sub-band is , is a decimal that satisfies the sine law, m is the number of r, is the dwell time, and T is the sweep period.

6. The method according to claim 3, characterized in that For equally spaced comb spectrum swept noise, the center frequency of each sub-band is determined according to the minimum center frequency of the sub-band; wherein the minimum center frequency of the sub-band is calculated by the following formula: ， is the minimum center frequency of the sub-band, is the center frequency to be set, is the number of spectral points, n≥2, is the spectrum interval, [·] represents the rounding operation; Then the center frequency of each subband is , is the sub-band center frequency, is the current count, i≤n.

7. The method according to claim 3, characterized in that For the custom comb spectrum swept noise, the center frequency of each subband is , To set the output RF frequency, is the local oscillator frequency.

8. A comb spectrum sweep noise interference generating device, characterized in that: Used to execute the embedded program to implement the method steps described in any one of claims 1-7.

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