Navigation jamming method and device for space-frequency adaptive anti-jamming unmanned aerial vehicle

Abstract

The present application belongs to the technical field of satellite navigation jamming, and relates to a navigation jamming method and device for space-frequency adaptive anti-jamming unmanned aerial vehicles. The method comprises the following steps: dividing the navigation signal spectrum into several equal parts; randomly generating a first random number; generating at least one second random number; assigning the frequency point values of the signals emitted by the first jammer and the second jammer according to the value of the first random number and the second random number to obtain a frequency point signal, until the corresponding frequency point signals for all navigation signal spectrums are generated; converting the time domain signals to obtain the first sequence signal and the second sequence signal; and emitting the signals by the first jammer and the second jammer. The present application utilizes the characteristics of space-frequency adaptive processing, and through the cooperation of the two stations, induces the severe nonlinear phase frequency response of the spatial filter generated by the anti-jamming system, actively disturbs the phase of the satellite navigation signal, solves the problems of low efficiency and easy exposure of the traditional jamming, and can realize customized jamming.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of satellite navigation jamming, and particularly relates to a navigation jamming method and device for a space-frequency adaptive anti-jamming unmanned aerial vehicle. BACKGROUND

[0002] The positioning accuracy of a satellite navigation system directly determines the combat effectiveness of equipment such as unmanned aerial vehicles, precision-guided weapons and ships, and therefore the navigation anti-jamming capability has become a core index for weapon system deployment, and various anti-jamming technologies (such as spatial filtering and frequency domain narrowband suppression) have been widely applied to combat platforms. However, there are still significant bottlenecks in current battlefield jamming methods: traditional navigation jamming schemes rely on increasing power suppression or increasing the number of jamming sources, which not only leads to a large size of jamming equipment, a sharp increase in energy consumption and high deployment cost, but also has a very low cost-effectiveness, and high-power jamming is easy to be located by enemy reconnaissance, and multiple jamming sources are difficult to adapt to small combat platforms such as unmanned aerial vehicles. More importantly, such jamming is easily suppressed by existing anti-jamming systems through filtering and signal reconstruction techniques, and cannot truly damage the decoding and positioning functions of satellite navigation signals.

[0003] For the anti-space filtering method, if the traditional method is used to reduce the output signal-to-interference-and-noise ratio, the jamming direction needs to be close to the desired signal direction, the jamming power needs to be increased, and the number of jamming sources needs to be increased, but these measures have too many constraints for the jamming opponent, and there are too many limitations in actual application. For radar detection, the higher the signal-to-interference-and-noise ratio after matched filtering, the higher the corresponding detection probability, but the higher the sampling signal input to the matched filter, the higher the signal-to-interference-and-noise ratio after matched filtering is not necessarily achieved, and the same is true for GPS signals, making it difficult to achieve a more efficient jamming method.

[0004] With the large-scale addition of high-performance anti-jamming systems to equipment such as unmanned aerial vehicles, the effectiveness of traditional jamming methods continues to decline, and there is an urgent need for a method that does not rely on high power or multiple jamming sources to bypass the suppression mechanism of the anti-jamming system and directly damage the effectiveness of the satellite navigation signal, so as to achieve the combat goal of completing positioning although the anti-jamming system can suppress the jamming, which has become a core research pain point in the field of satellite navigation jamming. SUMMARY

[0005] To solve the above technical problems, the application provides a navigation jamming method and device for a space-frequency adaptive anti-jamming unmanned aerial vehicle.

[0006] In a first aspect, the application provides a navigation jamming method for a space-frequency adaptive anti-jamming unmanned aerial vehicle, comprising:

[0007] dividing the navigation signal spectrum into several equal parts;

[0008] randomly generating a first random number for each equal part of the navigation signal spectrum;

[0009] generating at least one second random number in a set value range according to the value of the first random number;

[0010] assigning the frequency point values of the first jammer transmission signal and the frequency point values of the second jammer transmission signal according to the value of the first random number and the generated second random number to obtain a transmission signal corresponding to a frequency point of one equal part of the navigation signal spectrum, until transmission signals corresponding to frequency points of all equal parts of the navigation signal spectrum are generated;

[0011] converting the frequency point values of all first jammer transmission signals into time domain signals to obtain a first sequence signal of the first jammer transmission signal, and converting the frequency point values of all second jammer transmission signals into time domain signals to obtain a second sequence signal of the second jammer transmission signal;

[0012] the first jammer transmits the first sequence signal, and the second jammer transmits the second sequence signal.

[0013] In a second aspect, the present application provides a navigation jamming device for space-frequency adaptive anti-jamming unmanned aerial vehicles, comprising a spectrum division unit, a first random number generation unit, a second random number generation unit, a transmission signal generation unit, a conversion unit, a first jammer and a second jammer.

[0014] The spectrum division unit is used to divide the navigation signal spectrum into several equal parts.

[0015] The first random number generation unit is used to randomly generate a first random number for each equal part of the navigation signal spectrum.

[0016] The second random number generation unit is used to generate at least one second random number in a set value range according to the value of the first random number.

[0017] The transmission signal generation unit is used to assign the frequency point values of the first jammer transmission signal and the frequency point values of the second jammer transmission signal according to the value of the first random number and the generated second random number to obtain a transmission signal corresponding to a frequency point of one equal part of the navigation signal spectrum, until transmission signals corresponding to frequency points of all equal parts of the navigation signal spectrum are generated.

[0018] The conversion unit is used to convert the frequency point values of all first jammer transmission signals into time domain signals to obtain a first sequence signal of the first jammer transmission signal, and convert the frequency point values of all second jammer transmission signals into time domain signals to obtain a second sequence signal of the second jammer transmission signal.

[0019] The first jammer is used to transmit the first sequence signal.

[0020] The second jammer is configured to transmit a second sequence signal.

[0021] Based on the above technical solution, the application can be further improved as follows.

[0022] Further, the first random number is any one of a first preset value, a second preset value and a third preset value.

[0023] Further, the first preset value is 1, the second preset value is 2 and the third preset value is 3.

[0024] Further, according to the value of the first random number, at least one second random number in a set value range is generated, including: if the value of the first random number is in a first set range, one second random number in the set value range is generated, otherwise, if the value of the first random number is in a second set range, two second random numbers in the set value range are generated.

[0025] Further, the value range of the first random number is [1, 3], the first set range is [1, 2] and the first random number is a positive integer.

[0026] Further, the set value range is [0.8, 1].

[0027] Further, according to the value of the first random number and the generated second random number, the frequency point value of the signal transmitted by the first jammer and the frequency point value of the signal transmitted by the second jammer are assigned, including:

[0028] If the value of the first random number is the first preset value, after generating one second random number in the set value range, the frequency point value of the signal transmitted by the first jammer is the second random number and the frequency point value of the signal transmitted by the second jammer is a fourth set value.

[0029] If the value of the first random number is the second preset value, after generating one second random number in the set value range, the frequency point value of the signal transmitted by the first jammer is the fourth set value and the frequency point value of the signal transmitted by the second jammer is the second random number.

[0030] If the value of the first random number is the third preset value, after generating two second random numbers in the set value range, the frequency point value of the signal transmitted by the first jammer is the first second random number and the frequency point value of the signal transmitted by the second jammer is the second second random number.

[0031] Further, the fourth set value is 0.

[0032] Further, the frequency domain frequency point values of all the first jammer transmitted signals are inverse fast Fourier transformed to obtain first sequence signals of the first jammer transmitted signals, and the frequency domain frequency point values of all the second jammer transmitted signals are inverse fast Fourier transformed to obtain second sequence signals of the second jammer transmitted signals.

[0033] The present application has the following advantages:

[0034] (1) The present application utilizes the characteristics of space-frequency adaptive processing, induces the severe nonlinear phase-frequency response of the space filter generated by the anti-jamming system through the spectrum cooperation of the two stations, actively disturbs the phase of the satellite navigation signal, and even if the anti-jamming system suppresses the jamming signal, the distorted phase will still make the receiver unable to complete code synchronization and carrier tracking, and finally positioning fails.

[0035] (2) The present application does not rely on high-power suppression, directly destroys the signal effectiveness through phase distortion, and has smaller size and lower energy consumption, which can be adapted to small platforms such as unmanned aerial vehicles and individual equipment, and solves the problems of low efficiency-cost ratio and easy exposure of traditional jamming.

[0036] (3) The interference logic of the present application is aimed at the signal structure itself, even if the anti-jamming system successfully suppresses the jamming signal, the distorted phase will still lead to acquisition and decoding failure, and this interference effect does not depend on the anti-jamming algorithm, but destroys the signal availability from the bottom, which is more difficult to defend.

[0037] (4) The present application can accurately aim at the space-frequency response characteristics of the anti-jamming system through the spectrum cooperation of the two stations and the subband design, and can adjust the phase distortion strategy to induce the nonlinear phase-frequency response of the filter for different frequency bands and different anti-jamming algorithm platforms, realize customized interference, and is more widely applicable. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The principle diagram of the navigation jamming method for the space-frequency adaptive anti-jamming unmanned aerial vehicle provided for the embodiment 1 of the present application is shown in the figure.

[0039] Figure 2 The principle diagram of the subband space filter for the space-frequency processing is shown in the figure.

[0040] Figure 3 The principle diagram of the non-steady-state jamming influence mode is shown in the figure.

[0041] Figure 4 The principle diagram of the input signal-to-interference-and-noise ratio small leading to poor satellite acquisition performance is shown in the figure.

[0042] Figure 5 The diagram showing the influence of the input signal amplitude / signal-to-interference-and-noise ratio on the output signal-to-interference-and-noise ratio is shown in the figure.

[0043] Figure 6A schematic diagram for input signal amplitude / SINR unchanged and output SINR / capture performance reduced reduction;

[0044] Figure 7 A schematic diagram for two-dimensional filter characteristic representation;

[0045] Figure 8 A flowchart for the specific embodiment of the navigation jamming method for the space-frequency adaptive anti-jamming unmanned aerial vehicle;

[0046] Figure 9 A simulation diagram for the phase disturbance condition near 46.52MHz;

[0047] Figure 10 A principle block diagram of the navigation jamming device for the space-frequency adaptive anti-jamming unmanned aerial vehicle. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0049] Embodiment 1

[0050] As an embodiment, as shown in the accompanying drawings, Figure 1 To solve the above technical problems, the embodiment provides a navigation jamming method for a space-frequency adaptive anti-jamming unmanned aerial vehicle, which comprises:

[0051] Divide the navigation signal spectrum into several equal parts;

[0052] Randomly generate a first random number for each equal part of the navigation signal spectrum;

[0053] According to the value of the first random number, generate at least one second random number in a set value range;

[0054] According to the value of the first random number and the generated second random number, assign values to the frequency domain frequency point values of the first jammer transmission signal and the frequency domain frequency point values of the second jammer transmission signal, to obtain a transmission signal corresponding to a frequency point of an equal part of the navigation signal spectrum, until transmission signals corresponding to frequency points are generated for all equal parts of the navigation signal spectrum;

[0055] Convert the frequency domain frequency point values of all the first jammer transmission signals into time domain signals to obtain a first sequence signal of the first jammer transmission signal, and convert the frequency domain frequency point values of all the second jammer transmission signals into time domain signals to obtain a second sequence signal of the second jammer transmission signal;

[0056] The first jammer transmits a first sequence of signals, and the second jammer transmits a second sequence of signals.

[0057] In traditional bi-station scintillation jamming techniques, the alternating transmission of two jamming stations prevents the anti-jamming weights from converging effectively. The core idea of ​​traditional bi-station scintillation jamming is to disrupt the weight convergence process of the anti-jamming system through the alternation of signal transmission timing. The two jamming stations do not collaboratively plan the spectrum; instead, they adopt an alternating transmission mode—one jamming station transmits while the other remains silent. By periodically switching transmission states, the jamming signal received by the anti-jamming system appears as pulse-like scintillation in the time domain. This design utilizes the agility of the interference spatial domain, causing the spatial filtering weights of the space-frequency adaptive system to fail to converge effectively, never reaching a stable optimal weight, thus maintaining a certain level of interference residue and achieving the jamming effect.

[0058] This invention also adopts a dual-station mode, but unlike the above methods, this invention uses the spectrum coordination of the dual stations to form completely different spatial filters for adjacent sub-bands of the navigation anti-interference system, thereby causing the phase frequency response characteristics of the space-frequency adaptive system to exhibit severe nonlinear characteristics, destroying the phase of the satellite navigation signal, and thus disrupting the decoding of the satellite navigation signal.

[0059] For space-frequency filters, the interference signal is divided into sub-bands. When the number of sub-bands is sufficient, each sub-band can be considered a narrowband or even a single-frequency filter. Therefore, using spatial adaptive weights for each sub-band can effectively suppress interference, as shown in the attached figure. Figure 2 The diagram shows the principle of subband spatial filtering in spatial frequency processing.

[0060] Commonly used non-steady-state interference methods, such as time-domain, spatial-domain, and frequency-domain non-steady-state interference, all utilize the time-varying statistical characteristics of interference. For example, in spatial non-steady-state interference, the direction of the incoming interference wave flickers, causing a difference between the notch direction formed by the current weights and the current interference direction. This mismatch between the notch direction and the interference direction reduces interference suppression capability, thus increasing interference residue and overall interference effectiveness. Similarly, time-domain and frequency-domain non-steady-state interference also achieve time-varying interference statistical characteristics in the spatial-frequency domain. This prevents the converged weights from effectively matching the current transient interference, reducing anti-interference effectiveness and enhancing overall interference effectiveness. All these methods increase interference residue, meaning the interference cannot be completely suppressed. This manifests as an increase in the amplitude of the output signal after interference suppression, a decrease in the signal-to-interference-plus-noise ratio (SNR), and consequently, a decrease in anti-interference effectiveness. For the interfering party, however, the interference effectiveness is enhanced. The effects are illustrated in the appendix. Figure 3 The diagram shows the principle of the non-steady-state disturbance effect.

[0061] However, when using space-frequency filters, the broadband interference suppression problem is transformed into a set of spatial filters. For each set of spatial filters, the number of filter weights is extremely limited. For example, with a 4-channel receiving antenna, each set of adaptive weights has only 3, and even with a 7-channel receiving antenna, each set of adaptive weights has only 6. The reduction in the number of weights greatly increases the convergence speed of the adaptive weights, while also significantly reducing the number of snapshots in the interference statistics. Therefore, the effectiveness of space-frequency interference suppression algorithms is reduced when using space-time adaptive processing to effectively handle time-varying interference. The fast convergence performance of space-frequency adaptive processing allows non-steady-state interference to be considered as stationary interference even in extremely short time intervals. Each set of space-frequency filters can form a null notch aligned with the direction of interference in a very short time, resulting in a small output signal amplitude or a high signal-to-interference-plus-noise ratio.

[0062] Based on the above analysis, if traditional approaches are used to reduce the output signal-to-interference-plus-noise ratio (SNR) in counter-spatial filtering methods, it is necessary to move the interference direction closer to the desired signal direction, increase the interference power, and increase the number of interference sources. However, these measures impose too many constraints on the counter-interference party and have significant limitations in practical applications. GPS (Global Positioning System) uses QPSK (Quadrature Phase-Shift Keying) to encode signals. After space-frequency adaptive processing, a filtered output signal is obtained, which is also the decoded input signal. At this point, the filtered output SNR is the same as the decoded input SNR. For radar detection, a higher SNR after matched filtering corresponds to a higher detection probability. However, a higher sampling signal at the input of the matched filter does not necessarily guarantee a higher SNR after matched filtering. The same applies to GPS signals. The purpose of this invention is to disrupt the phase of GPS signals to achieve a more efficient jamming method.

[0063] If the goal is to maximize residual interference, the aim is to reduce the signal-to-interference-plus-noise ratio (SNR) of the filtered output, which in turn reduces the SNR of the decoding input, thereby lowering GPS satellite acquisition performance. However, the inability to reduce the decoding input SNR does not necessarily mean that GPS satellite acquisition performance cannot be reduced. (See attached image) Figure 4 The diagram shows the principle behind poor satellite acquisition performance caused by a low input signal-to-interference-plus-noise ratio.

[0064] Based on the diagram of the coded signal, it can be represented as shown in the attached figure. Figure 5 The diagram illustrates the impact of input signal-to-interference-plus-noise ratio (SNR) on output SNR. A high SNR does not necessarily mean a high acquisition capability of the navigation receiver. Conversely, a low residual interference and a high input SNR do not necessarily result in a high output SNR. (See attached diagram.)Figure 6 The schematic diagram of the input signal-to-interference-and-noise ratio being constant and the output signal-to-interference-and-noise ratio being reduced is shown.

[0065] The Figure 6 A special example is given because the matching filter output signal-to-interference-and-noise ratio and the acquisition performance are reduced due to the signal position moving or position exchange. The satellite navigation signal relies on the consistency of the coded phase to complete acquisition and decoding, as shown in the accompanying Figure 6 As shown, the signal phase distortion will cause the matching filter output signal-to-interference-and-noise ratio to drop sharply. The present application uses the characteristics of space-frequency adaptive processing to induce the space filter generated by the anti-jamming system to produce a dramatic nonlinear phase response, so that the satellite navigation signal phase is actively disturbed. Even if the anti-jamming system suppresses the interference signal, the distorted phase will still make the receiver unable to complete code synchronization and carrier tracking, and finally positioning fails.

[0066] Generally, due to the distortion of the coded signal phase, even in the case of constant input signal-to-interference-and-noise ratio, the signal decoding performance will be reduced, and this is an important way for interference countermeasures space-frequency adaptive processing, that is, how to make the coded signal transmission phase distortion.

[0067] As shown in the schematic diagram of the two-dimensional filter characteristic representation, for space-frequency adaptive processing, that is, a two-dimensional filter, the filter theory and method can be used for targeted analysis. The design purpose of the present application is to make the space-time two-dimensional filter frequency phase response calculated by the weight value of the space-frequency adaptive processing present dramatic fluctuations and nonlinearity. When the inverse Fourier transform is transformed to the time domain after the space-frequency adaptive processing, the phase is disturbed. Figure 7

[0068] Optionally, the first random number is any one of a first preset value, a second preset value, and a third preset value.

[0069] Optionally, the first preset value is 1, the second preset value is 2, and the third preset value is 3.

[0070] Optionally, according to the value of the first random number, at least one second random number in a set value range is generated, including: if the value of the first random number is in a first set range, a second random number in the set value range is generated, otherwise, if the value of the first random number is in a second set range, two second random numbers in the set value range are generated.

[0071] Optionally, the value range of the first random number is [1, 3], the first set range is [1, 2], and the first random number is a positive integer.

[0072] Optionally, the set value range is [0.8, 1].

[0073] ​The exemplary interference signal frequency band is divided into N points, N is 1024 or 2048, and the same idea is also used when other values are taken.

[0074] In the generation of the amplitude values of different interference signal frequency points, a random number between 0.8 and 1 is taken as an example, which is to consider that the interference signal power cannot be too small, and the same principle is also used when other similar values are taken.

[0075] Optionally, according to the value of the first random number and the generated second random number, the frequency point value of the first jammer transmitting signal and the frequency point value of the second jammer transmitting signal are assigned, including:

[0076] If the value of the first random number is a first preset value, after generating a second random number in a set value range, the frequency point value of the first jammer transmitting signal is the second random number, and the frequency point value of the second jammer transmitting signal is a fourth set value;

[0077] If the value of the first random number is a second preset value, after generating a second random number in a set value range, the frequency point value of the first jammer transmitting signal is a fourth set value, and the frequency point value of the second jammer transmitting signal is the second random number;

[0078] If the value of the first random number is a third preset value, after generating two second random numbers in a set value range, the frequency point value of the first jammer transmitting signal is the first second random number, and the frequency point value of the second jammer transmitting signal is the second second random number.

[0079] Optionally, the fourth set value is 0.

[0080] Optionally, the frequency point values of all first jammer transmitting signals are subjected to inverse fast Fourier transform to obtain first sequence signals of the first jammer transmitting signals, and the frequency point values of all second jammer transmitting signals are subjected to inverse fast Fourier transform to obtain second sequence signals of the second jammer transmitting signals.

[0081] As shown in the flowchart of the specific embodiment of the navigation interference method of the space-frequency adaptive anti-interference unmanned aerial vehicle. Figure 8

[0082] Step 1: divide the transmitting signal spectrum into N equal parts; for example, N can be 1024 or 2048;

[0083] For each n with a value of 1 to N, the following loop is performed to complete the design of the transmitting signal for each specific frequency point;

[0084] ​This step involves three cases. If k=1, a random number 'a' is generated, with a value within the range of [0.8, 1]. A[n] = a, B[n] = 0, where A[n] is the frequency point value of the signal transmitted by jammer 1, and B[n] is the frequency point value of the signal transmitted by jammer 1. The value range of [0.8, 1] indicates that the amplitude is too small, affecting the interference power, while also giving the interference strength a certain degree of randomness, forming an unstable state of interference between different frequency points. If k=2, a random number 'b' is generated, with a value within the range of [0.8, 1]. A[n] = 0, B[n] = b. If k=3, two random numbers 'a' and 'b' are generated, both with values ​​within the range of [0.8, 1]. A[n] = a, B[n] = b.

[0085] Determine if n has completed the cycle from 1 to N. If not, then n = n + 1 and proceed to the second step. If n has reached the maximum value N, then proceed to the next step.

[0086] The sequence of signals transmitted by jammer 1 is S1=IFFT(A), and the sequence of signals transmitted by jammer 2 is S2=IFFT(B).

[0087] Jammer 1 transmits signal S1; Jammer 2 transmits signal S2.

[0088] As attached Figure 9 The simulation diagram shows the phase disturbance around 46.52MHz. Jammer 1 is located at 20° and jammer 2 is located at 30°, with a signal carrier frequency of 46.52MHz. It can be seen that the phase changes between different frequency points are significant, with a difference of approximately 100°. This indicates that the interference scheme designed in this way can effectively increase the difference in weights between adjacent frequency points, thereby increasing the phase difference between frequency points.

[0089] This approach focuses on disrupting signal effectiveness. Even if the anti-jamming system successfully filters out the interference signal, demodulation and positioning cannot be completed due to the phase distortion of the target satellite signal, forming a unique technical path that leads to the failure of the anti-jamming system. This approach breaks through the limitations of traditional jamming techniques, providing a new research direction for the field of satellite navigation jamming. It can promote the development of subsequent jamming technologies towards precisely disrupting signal structure and countering high-performance anti-jamming systems at low cost, and has significant technological leading value.

[0090] The invention proposes a dual-band interference spectrum coordination method, and through design, multiple states can be set for each frequency point. If we only divide it according to whether there is interference, there are three cases: interference comes from direction one, interference comes from direction two, and interference exists in both direction one and direction two. Through this design, the weights formed by each frequency point are significantly different from the adaptive weights of adjacent frequency points.

[0091] The purpose of the present application is not to increase interference residues, but to distort the expected satellite navigation signal phase, and this purpose is achieved through the way of double interference spectrum cooperation.

[0092] Traditional interference needs to continuously increase power or increase interference sources to counter anti-interference systems, but the present application does not rely on high-power suppression, directly destroys the effectiveness of the signal through phase distortion, and the interference device is smaller in size and lower in energy consumption, which can be adapted to small platforms such as unmanned aerial vehicles and individual equipment, solving the problems of low efficiency and easy exposure of traditional interference.

[0093] Conventional interference is easily counteracted by anti-interference algorithms, but the interference logic of the present application is directed to the signal structure itself, and even if the anti-interference system successfully suppresses the interference signal, the distorted phase will still cause acquisition and decoding failure. This interference effect does not depend on anti-interference algorithms, but rather destroys the availability of the signal from the bottom up, making it more difficult to defend.

[0094] Through double-station spectrum cooperation and sub-band design, the present application can accurately aim at the space-frequency response characteristics of anti-interference systems, and for platforms with different frequency bands and different anti-interference algorithms, it can induce nonlinear phase-frequency response of filters by adjusting phase distortion strategy, realize customized interference, and be more widely applicable.

[0095] Embodiment 2

[0096] Based on the same principle as the method shown in Embodiment 1 of the present application, as shown in the accompanying drawings Figure 10 The present application also provides a navigation interference device for a space-frequency adaptive anti-interference unmanned aerial vehicle in an embodiment of the present application, which includes a spectrum division unit, a first random number generation unit, a second random number generation unit, a transmitted signal generation unit, a conversion unit, a first jammer and a second jammer.

[0097] The spectrum division unit is used to divide the navigation signal spectrum into several equal parts.

[0098] The first random number generation unit is used to randomly generate a first random number for each equal part of the navigation signal spectrum.

[0099] The second random number generation unit is used to generate at least one second random number within a set value range according to the value of the first random number.

[0100] The transmitted signal generation unit is used to assign values to the frequency point values of the first jammer transmitted signal and the frequency point values of the second jammer transmitted signal according to the value of the first random number and the generated second random number, to obtain a transmitted signal corresponding to a frequency point for each equal part of the navigation signal spectrum, until transmitted signals corresponding to frequency points for all equal parts of the navigation signal spectrum are generated.

[0101] a conversion unit, configured to convert frequency point values of all first jammer transmission signals into time domain signals to obtain first sequence signals of the first jammer transmission signals, and convert frequency point values of all second jammer transmission signals into time domain signals to obtain second sequence signals of the second jammer transmission signals;

[0102] a first jammer, configured to transmit the first sequence signals;

[0103] a second jammer, configured to transmit the second sequence signals.

[0104] Optionally, the first random number is any one of a first preset value, a second preset value and a third preset value.

[0105] Optionally, the first preset value is 1, the second preset value is 2, and the third preset value is 3.

[0106] Optionally, according to the value of the first random number, at least one second random number in a set value range is generated, including: if the value of the first random number is in a first set range, one second random number in the set value range is generated, otherwise, if the value of the first random number is in a second set range, two second random numbers in the set value range are generated.

[0107] Optionally, the value range of the first random number is [1, 3], the first set range is [1, 2], and the first random number is a positive integer.

[0108] Optionally, the set value range is [0.8, 1].

[0109] Optionally, according to the value of the first random number and the generated second random number, the frequency point values of the first jammer transmission signals and the frequency point values of the second jammer transmission signals are assigned values, including:

[0110] If the value of the first random number is the first preset value, after generating one second random number in the set value range, the frequency point value of the first jammer transmission signal is the second random number, and the frequency point value of the second jammer transmission signal is a fourth set value.

[0111] If the value of the first random number is the second preset value, after generating one second random number in the set value range, the frequency point value of the first jammer transmission signal is the fourth set value, and the frequency point value of the second jammer transmission signal is the second random number.

[0112] If the value of the first random number is the third preset value, after generating two second random numbers in the set value range, the frequency point value of the first jammer transmission signal is the first second random number, and the frequency point value of the second jammer transmission signal is the second second random number.

[0113] Optionally, the fourth set value is 0.

[0114] Optionally, the frequency domain frequency point values of all the first jammer transmitting signals are inverse fast Fourier transformed to obtain first sequence signals of the first jammer transmitting signals, and the frequency domain frequency point values of all the second jammer transmitting signals are inverse fast Fourier transformed to obtain second sequence signals of the second jammer transmitting signals.

[0115] The preferred embodiments of the present application have been described above with the preferred embodiments, but the present application is not limited to the above examples and can be variously changed and modified by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A navigation jamming method for a space-frequency adaptive anti-jamming unmanned aerial vehicle, characterized in that, The method comprises the following steps: dividing the navigation signal spectrum into several equal parts; generating a first random number for each part of the navigation signal spectrum; generating at least one second random number in a set value range according to the value of the first random number; assigning the frequency domain frequency point value of the first jammer transmission signal and the frequency domain frequency point value of the second jammer transmission signal according to the value of the first random number and the generated second random number, to obtain a transmission signal corresponding to a frequency point of one part of the navigation signal spectrum; if the value of the first random number is a first preset value, after generating a second random number in a set value range, the frequency domain frequency point value of the first jammer transmission signal is the second random number, and the frequency domain frequency point value of the second jammer transmission signal is a fourth set value; if the value of the first random number is a second preset value, after generating a second random number in a set value range, the frequency domain frequency point value of the first jammer transmission signal is a fourth set value, and the frequency domain frequency point value of the second jammer transmission signal is the second random number; if the value of the first random number is a third preset value, after generating two second random numbers in a set value range, the frequency domain frequency point value of the first jammer transmission signal is the first second random number, and the frequency domain frequency point value of the second jammer transmission signal is the second second random number; until the transmission signal corresponding to the frequency point of all parts of the navigation signal spectrum is generated; converting the frequency domain frequency point values of all first jammer transmission signals into time domain signals to obtain a first sequence signal of the first jammer transmission signal, and converting the frequency domain frequency point values of all second jammer transmission signals into time domain signals to obtain a second sequence signal of the second jammer transmission signal; the first jammer transmits the first sequence signal, and the second jammer transmits the second sequence signal.

2. The method of claim 1, wherein, The value of the first random number is any one of the first preset value, the second preset value and the third preset value.

3. The method of claim 2, wherein, The first preset value is 1, the second preset value is 2, and the third preset value is 3.

4. The method of claim 1, wherein, Generating at least one second random number in a set value range according to the value of the first random number comprises: if the value of the first random number is in a first set range, generating a second random number in a set value range; otherwise, if the value of the first random number is in a second set range, generating two second random numbers in a set value range.

5. The method of claim 4, wherein, The value range of the first random number is [1, 3], the first set range is [1, 2], and the first random number is a positive integer.

6. The method of claim 1 or 4, wherein, The set value range is [0.8, 1].

7. The method of claim 1, wherein, The fourth set value is 0.

8. The method of claim 1, wherein, Converting the frequency domain frequency point values of all first jammer transmission signals into time domain signals to obtain a first sequence signal of the first jammer transmission signal, and converting the frequency domain frequency point values of all second jammer transmission signals into time domain signals to obtain a second sequence signal of the second jammer transmission signal.

9. The navigation jamming device for the space-frequency adaptive anti-jamming UAV, characterized in that, The method comprises the following steps: a spectrum division unit, a first random number generation unit, a second random number generation unit, a transmission signal generation unit, a conversion unit, a first jammer and a second jammer; the spectrum division unit is used for dividing the navigation signal spectrum into several equal parts; The first random number generating unit is configured to randomly generate a first random number for each equal part of the navigation signal spectrum; The second random number generating unit is configured to generate at least one second random number within a set value range according to the value of the first random number; The transmitting signal generating unit is configured to assign the frequency point value of the first jammer transmitting signal and the frequency point value of the second jammer transmitting signal according to the value of the first random number and the generated second random number, so as to obtain a transmitting signal corresponding to a frequency point of each equal part of the navigation signal spectrum; If the value of the first random number is a first preset value, after the second random number within a set value range is generated, the frequency point value of the first jammer transmitting signal is the second random number, and the frequency point value of the second jammer transmitting signal is a fourth set value; If the value of the first random number is a second preset value, after the second random number within a set value range is generated, the frequency point value of the first jammer transmitting signal is the fourth set value, and the frequency point value of the second jammer transmitting signal is the second random number; If the value of the first random number is a third preset value, after the second random numbers within two set value ranges are generated, the frequency point value of the first jammer transmitting signal is the first second random number, and the frequency point value of the second jammer transmitting signal is the second second random number; Until the transmitting signal corresponding to the frequency point of all equal parts of the navigation signal spectrum is generated; The converting unit is configured to convert the frequency point values of all first jammer transmitting signals into time domain signals to obtain a first sequence signal of the first jammer transmitting signal, and convert the frequency point values of all second jammer transmitting signals into time domain signals to obtain a second sequence signal of the second jammer transmitting signal; The first jammer is configured to transmit the first sequence signal; The second jammer is configured to transmit the second sequence signal.

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