Frequency hopping anti-jamming communication system and method based on chaotic random number

Abstract

The application provides a frequency hopping anti-interference communication system and method based on chaotic random numbers, which comprises a transmitting end information modulation module, which modulates and processes an original baseband signal; a transmitting end frequency hopping module, which determines a frequency hopping channel frequency; a transmitting end frequency mixer module, which mixes and performs up-conversion processing; a transmitting end antenna module, which transmits and emits a radio frequency signal waveguide to free space; a receiving end antenna module, which receives a transmitting signal; a receiving end frequency mixer module, which transmits the signal after frequency conversion to a receiving end intermediate frequency filter module; a receiving end frequency hopping module, which determines a frequency hopping channel frequency; a receiving end intermediate frequency filter, which performs filtering processing on the signal after frequency conversion; and a receiving end baseband signal module, which obtains the original baseband signal transmitted by the transmitting end after filtering processing. The application combines random channel selection and chaotic channel selection in the frequency hopping module, realizes the transmission of information without pre-sharing of an initial seed, and improves the security of the communication system.

Description

Technical Field

[0001] This invention relates to the field of anti-interference communication technology, and more specifically, to a frequency hopping anti-interference communication system and method based on chaotic random numbers. Background Technology

[0002] Currently, the anti-jamming communication technology field mainly focuses on frequency hopping and spread spectrum, with frequency hopping being the most widely used and still the mainstream anti-jamming technology system, and its technology continues to evolve. In addition, it encompasses various anti-jamming methods in the time, space, frequency, and network domains, specifically including time hopping, bursting, smart antennas, and directional communication. The main principle of frequency hopping communication is that the transmission frequency discretely hops within a set of pre-specified frequencies according to a coded sequence, thereby expanding the transmission spectrum. Frequency hopping generally uses pseudo-random sequences to control the frequency synthesizer, constructing frequency hopping commands and frequency hopping patterns, and randomly selecting the transmission frequency according to the frequency hopping commands. At the receiving end, a local pseudo-random sequence generator, identical to that at the transmitting end, is needed to construct frequency hopping commands to control the local frequency synthesizer in order to recover the original signal. Therefore, the pseudo-random sequence generator plays a crucial role, and the performance of the frequency hopping pattern has a decisive impact on the anti-interception and anti-jamming performance of the frequency hopping communication system. Increasing the hopping rate and selecting a suitable frequency hopping pattern are important methods to improve frequency hopping capability; however, increasing the hopping rate is limited by the limitations of the equipment's electronic constraints, and its effectiveness is limited. Therefore, designing a well-designed pseudo-random sequence generator is crucial to ensuring that a frequency-hopping communication system has optimal anti-interference and anti-interception characteristics.

[0003] Pseudo-random number generators are indispensable tools in modern computing, primarily used to generate fast, periodic random numbers through algorithmic design and an initial seed value. However, current frequency-hopping anti-jamming communication based on pseudo-random number generators has some drawbacks. First, the initial seed value needs to be shared in advance; if the initial seed and algorithm are compromised, the seed or random sequence data may be copied or even predicted in advance. Second, the generated random sequence has a limited length and exhibits periodicity, which poses a vulnerability in scenarios requiring high confidentiality. With the continuous improvement of computing power, incidents of pseudo-random number-based frequency-hopping anti-jamming communication being compromised and intercepted are becoming increasingly common. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the purpose of this invention is to provide a frequency-hopping anti-interference communication system and method based on chaotic random numbers.

[0005] According to the present invention, a frequency-hopping anti-interference communication system based on chaotic random numbers includes:

[0006] The transmitter baseband signal module is used to provide the raw baseband signal for the communication system;

[0007] The transmitter information modulation module is used to modulate the original baseband signal;

[0008] The transmitter frequency hopping module is used to determine the frequency of the frequency hopping channel;

[0009] The transmitter mixer module is used to mix the modulated signal with the frequency hopping channel frequency for up-conversion processing.

[0010] The transmitting antenna module is used to transmit and transmit radio frequency signals into free space via waveguides.

[0011] The receiver antenna module is used to receive signals transmitted into free space by the transmitter antenna module;

[0012] The receiver mixer module is used to transmit the received signal to the receiver intermediate frequency filter after down-conversion by the receiver mixer.

[0013] The receiver frequency hopping module is used to determine the frequency of the frequency hopping channel;

[0014] The receiving-end intermediate frequency filter is used to perform intermediate frequency filtering on the signal after downconversion by the receiving-end mixer;

[0015] The receiver baseband signal module is used to obtain the original baseband signal transmitted from the transmitter after intermediate frequency filtering by the receiver intermediate frequency filter.

[0016] Preferably, both the transmitter frequency hopping module and the receiver frequency hopping module include a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer.

[0017] Preferably, the transmitter frequency hopping module and the receiver frequency hopping module can exchange initial seed values ​​during the random channel selection phase and apply the initial seed values ​​to the chaotic mapping during the chaotic channel selection phase to determine the frequency hopping channel frequency.

[0018] Preferably, the frequency synthesizer is used to generate the required frequency hopping channel frequency to ensure synchronization between the transmitter and receiver.

[0019] Preferably, it also includes a channel table to guide the random channel selection process at the transmitter and receiver.

[0020] A frequency-hopping anti-interference communication method based on chaotic random numbers provided by the present invention includes:

[0021] Preparation steps: Connect all modules in the system sequentially and set up the channel table;

[0022] Frequency hopping steps: After the transmitter and receiver select a channel in the random channel selection phase, they use the same initial seed value in the chaotic channel selection phase to determine the frequency hopping channel frequency through chaotic mapping.

[0023] Signal transmission steps: The baseband signal is modulated by the baseband signal module at the transmitting end through the information modulation module at the transmitting end, and then up-converted and modulated by the frequency hopping frequency obtained by the frequency hopping module at the transmitting end through the mixer module at the transmitting end. Finally, it is transmitted into free space through the antenna module at the transmitting end.

[0024] Signal reception steps: The receiving antenna module transmits the received radio frequency signal to the receiving mixer module. The signal is down-converted and modulated by the frequency hopping frequency obtained by the receiving frequency hopping module. After intermediate frequency filtering signal processing by the receiving intermediate frequency filter, the original baseband signal is obtained in the receiving baseband signal module.

[0025] Preferably, the frequency hopping step includes synchronizing the transmitter and receiver by exchanging initial seed values ​​to maintain frequency consistency during communication.

[0026] Preferably, the signal transmission step includes encoding and modulating the baseband signal at the transmitting end.

[0027] Preferably, the random channel selection phase includes generating random numbers using the frequency hopping modules at the transmitting and receiving ends, with the center frequency of the random channel transmission being [missing information].

[0028] f c =(1402+f n )MHz;

[0029] Among them, f n This represents the channel frequency bandwidth corresponding to channel n;

[0030] The chaotic channel selection phase includes enabling the transmitter and receiver to send and receive information on randomly selected frequencies. When the frequencies of the transmitter and receiver coincide, the transmitter and receiver exchange the initial seed value of the chaotic signal.

[0031] Preferably, the chaotic channel selection stage further includes inputting the initial seed value of the exchanged chaotic signal into the Lang-Kobayashi chaotic map, and obtaining the chaotic index value through iteration and algorithm processing; after determining the channel and frequency hopping channel frequency based on the channel table, the value is input into the frequency synthesizer.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. This invention improves the security of the communication system by combining random channel selection and chaotic channel selection in the frequency hopping module, thereby enabling information transmission without pre-sharing of the initial seed.

[0034] 2. This invention employs the Lang-Kobayashi chaotic map based on semiconductor laser nonlinear dynamics as a chaotic generator. The chaotic generator based on semiconductor laser nonlinear dynamics is an ideal source of random bits. In addition, it can generate a large positive Lyapunov exponent, supporting high-rate random bit generation.

[0035] 3. The frequency hopping module generation method in this invention is simple. By generating rules, initial conditions and mapping functions, a pseudo-random sequence that is almost impossible to decipher can be determined. The generated random sequence has good correlation and balance, which provides a reference for the development of anti-interference communication technology.

[0036] Other beneficial effects of the present invention will be explained in detail through the introduction of specific technical features and technical solutions in specific embodiments. Those skilled in the art should be able to understand the beneficial technical effects brought about by these technical features and technical solutions through the introduction of these technical features and technical solutions. Attached Figure Description

[0037] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0038] Figure 1 This is a system block diagram of the present invention.

[0039] Figure 2 This is a schematic diagram of random channel selection in this invention.

[0040] Figure 3 This is a schematic diagram of chaotic channel selection in this invention.

[0041] Figure 4 This is a schematic diagram of the channel frequency table in this invention.

[0042] Figure 5 This is a flowchart of the method of the present invention.

[0043] Figure Labels

[0044] Transmitter baseband signal module 1; Receiver antenna module 6

[0045] Transmitter modulation module 2; Receiver mixer module 7

[0046] Transmitter frequency hopping module 3; Receiver frequency hopping module 8

[0047] Transmitter mixer module 4; Receiver intermediate frequency filter 9

[0048] Transmitter antenna module 5; Receiver baseband signal module 10 Detailed Implementation

[0049] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0050] Reference Figure 1 As shown, a frequency-hopping anti-interference communication system based on chaotic random numbers includes:

[0051] Transmitter baseband signal module 1 is used to provide the original baseband signal of the communication system;

[0052] Transmitter information modulation module 2 is used to modulate the original baseband signal;

[0053] The transmitter frequency hopping module 3 includes a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer. The frequency hopping module determines the frequency of the frequency hopping channel. Specifically, in the random channel selection stage, initial seed values ​​are exchanged. In the chaotic channel selection stage, the initial seed values ​​are applied to the chaotic mapping to determine the frequency of the frequency hopping channel.

[0054] Transmitter mixer module 4 is used to mix the modulated signal with the frequency hopping channel frequency for upconversion processing;

[0055] The transmitting antenna module 5 is used to transmit and transmit radio frequency signals into free space via waveguides.

[0056] The receiving antenna module 6 is used to receive signals transmitted into free space by the transmitting antenna module 5.

[0057] The receiver mixer module 7 is used to transmit the received signal to the receiver intermediate frequency filter 9 after downconversion by the receiver mixer.

[0058] The receiver frequency hopping module 8 includes a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer. The frequency hopping module determines the frequency of the frequency hopping channel. Specifically, in the random channel selection stage, initial seed values ​​are exchanged, and in the chaotic channel selection stage, the initial seed values ​​are applied to the chaotic mapping to determine the frequency of the frequency hopping channel.

[0059] The intermediate frequency filter 9 at the receiving end performs intermediate frequency filtering on the signal after down-conversion by the mixer at the receiving end.

[0060] The baseband signal module 10 at the receiving end obtains the original baseband signal transmitted from the transmitting end after processing such as intermediate frequency filtering by the intermediate frequency filter 9 at the receiving end.

[0061] Reference Figure 5As shown, based on the above system, the present invention also provides a communication method for a frequency hopping anti-interference communication system based on chaotic random numbers, comprising the following steps:

[0062] Preparation steps: The operator connects the transmitter baseband signal module 1, transmitter information modulation module 2, transmitter frequency hopping module 3, transmitter mixer module 4, and transmitter antenna module 5; the operator connects the receiver antenna module 6, receiver mixer module 7, receiver frequency hopping module 8, receiver intermediate frequency filter 9, and receiver baseband signal module 10, and prepares the channel table.

[0063] Frequency hopping steps: The transmitter frequency hopping module 3 and receiver frequency hopping module 8 include a random channel selection stage and a chaotic channel selection stage. In the channel selection stage, the transmitter and receiver send and receive information on randomly selected frequencies. When the transmitter and receiver frequencies coincide, the transmitter and receiver exchange the initial seed value of the chaotic signal. In the chaotic channel selection stage, after chaotic mapping, the channel and frequency hopping channel frequency are determined and input to the frequency synthesizer.

[0064] Signal transmission steps: The baseband signal to be transmitted is encoded and modulated by the baseband signal module 1 at the transmitting end through the information modulation module 2 at the transmitting end, and then up-converted and modulated by the frequency hopping frequency obtained by the frequency hopping module 3 at the transmitting end through the mixer module 4 at the transmitting end. Finally, it is transmitted to free space through the antenna module 5 at the transmitting end.

[0065] Signal reception steps: The receiving antenna module 6 transmits the received radio frequency signal to the receiving mixer module 7, and performs down-conversion modulation on the receiving mixer module 7 with the frequency hopping frequency obtained by the receiving frequency hopping module 8. After signal processing such as intermediate frequency filtering by the receiving intermediate frequency filter 9, the original baseband signal is obtained in the receiving baseband signal module 10.

[0066] The above are basic embodiments of the present invention. The technical solution of the present invention will be further described below through a preferred embodiment.

[0067] Example 1

[0068] like Figure 1 As shown, a frequency-hopping anti-interference communication system based on chaotic random numbers includes:

[0069] Transmitter baseband signal module 1, transmitter information modulation module 2, transmitter frequency hopping module 3, transmitter mixer module 4, transmitter antenna module 5, receiver antenna module 6, receiver mixer module 7, receiver frequency hopping module 8, receiver intermediate frequency filter 9, receiver baseband signal module 10;

[0070] The transmitting baseband signal module 1 is used to provide the original baseband signal of the communication system; specifically, it transmits the provided original baseband signal of the communication system to the transmitting information modulation module 2.

[0071] The transmitter information modulation module 2 encodes and modulates the baseband signal, and then transmits the signal to the transmitter mixer module 4;

[0072] The transmitter frequency hopping module 3 includes a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer to determine the frequency of the frequency hopping channel. Specifically, as shown... Figure 2 As shown, during the random channel selection phase, the transmitter and receiver do not rely on any encrypted channel, but instead transmit and receive on randomly selected frequencies. At a specific moment, the transmitter and receiver channel frequencies coincide, and during this period, as... Figure 3 As shown, the transmitter exchanges the initial seed value of the chaotic signal with the receiver, and then enters the chaos selection stage. The initial seed value obtained by the exchange is input into the Lang-Kobayashi chaotic map, as shown in formulas (1)-(3):

[0073]

[0074] Where E(t) is the electric field intensity, Φ(t) is the electric field phase, N(t) is the carrier density, G(N) is the gain coefficient, and τ p For photon lifetime, τ s For carrier lifetime, τ in ω0 is the round-trip time of the inner cavity, ω0 is the undisturbed angular frequency of the semiconductor laser, τ = 2L / c is the round-trip time of the outer cavity (L is the length of the outer cavity, c is the speed of light), e is the elementary charge, and V is the volume of the active region. The dynamic parameter values ​​of each semiconductor laser can be experimentally measured by the four-wave mixing method. Other values ​​are initial seed values, including the linewidth enhancement factor (α), the outer cavity length (L), the injection current density (J), and the feedback intensity (κ). For specific physical meanings, please refer to B. Nie, et al., IEEE J. Lightwave Technol., 38, (19), pp. 5423-5429, 2020 and B. Nie, et al., IEEE J. Lightwave Technol., 38, (19), pp. 5423-5429, 2020. Technol., 40, (20), pp. 6737-6744, 2022. By inputting the initial seed value, the fourth-order Runge-Kutta algorithm is used to solve formulas (1)-(3). Through multiple iterations of the chaotic equation, different discrete values ​​E(t) are obtained. After normalization, the obtained discrete E(t) is in the range of [-1, +1]. The following formula (4) is used:

[0075] E i =int[(E(t)] max ×10q )] Formula (4)

[0076] Where q is an integer, q≥3, and the maximum value of the obtained discrete chaotic value E(t) is E(t). max After the int operation, it is converted into a chaotic integer value E. i Then use formula (5):

[0077] I i =E i mod N f Formula (5)

[0078] Where, N f For the total number of frequency hopping channels, the chaotic integer value E i Perform a mod operation to obtain the chaos exponent value I. i This determines the channel number, and then... Figure 4 The channel frequency table shown is used to determine the frequency hopping channel frequency.

[0079] Transmitter mixer module 4 is used to mix the modulated signal with the carrier of transmitter frequency hopping module 3 and perform up-conversion processing.

[0080] The transmitting antenna module 5 is used to transmit and transmit radio frequency signals into free space via waveguides.

[0081] The receiving antenna module 6 is used to receive the signal transmitted into free space by the transmitting antenna module 5 and transmit it to the receiving mixer module 7.

[0082] The receiver mixer module 7 is used to transmit the received signal to the receiver intermediate frequency filter 9 after downconversion by the receiver mixer.

[0083] The receiver frequency hopping module 8 includes a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer to determine the frequency of the frequency hopping channel. Specifically, the implementation method is the same as the working principle of the transmitter frequency hopping module;

[0084] The baseband signal module 10 at the receiving end obtains the original baseband signal transmitted from the transmitting end after processing such as intermediate frequency filtering by the intermediate frequency filter 9 at the receiving end.

[0085] Reference Figure 5 As shown, a frequency hopping anti-interference communication method based on chaotic random numbers is described, and the actual operation steps are as follows.

[0086] Preparation Step A: Preparatory work; specifically as follows:

[0087] Step A1: The operator connects the transmitter baseband signal module 1, transmitter information modulation module 2, transmitter frequency hopping module 3, transmitter mixer module 4, and transmitter antenna module 5, and checks the transmitter. If any abnormality is found, it should be investigated in time.

[0088] Step A2: The operator connects the receiving antenna module 6, the receiving mixer module 7, the receiving frequency hopping module 8, the receiving intermediate frequency filter 9, and the receiving baseband signal module 10, and checks the receiving end. If any abnormality is found, it should be investigated in time.

[0089] Step A3: The operator prepares the channel table, specifically, such as... Figure 4 The channel table shown uses a frequency band of 1.4 GHz and consists of 49 channels, each with a bandwidth of 1 MHz. The starting frequency is 1400 MHz, and the ending frequency is 1450.5 MHz. Let the symbol n represent a channel, and its range be n = {0, 1, 2, 3, ..., 48}.

[0090] Frequency hopping module step S: The frequency hopping module includes a random channel selection stage and a chaotic channel selection stage; specifically as follows:

[0091] Step S1: Random channel selection stage, specifically, the random number generation step of the frequency hopping modules at the transmitting and receiving ends, where the center frequency f of the random channel transmission is... c =(1402+f n )MHz, f n The channel frequency bandwidth corresponding to channel n, such as Figure 2 As shown, during the channel selection phase, the transmitter and receiver send and receive information on randomly selected frequencies. When the frequencies of the transmitter and receiver coincide, it is the time for the transmitter and receiver to exchange the initial seed value of the chaotic signal.

[0092] Step S2: Then proceed to the chaotic channel selection stage, specifically, as follows... Figure 3 As shown, the initial seed value of the chaotic signal obtained by the exchange is input into the Lang-Kobayashi chaotic map. After iteration and algorithm processing, the chaotic exponent value is obtained. Figure 4 The channel table shown is used to determine the channel and frequency hopping channel frequency, which is then input into the frequency synthesizer.

[0093] Signal transmission steps: The baseband signal to be transmitted is encoded and modulated by the baseband signal module 1 at the transmitting end through the information modulation module 2 at the transmitting end, and then up-converted and modulated by the frequency hopping frequency obtained by the frequency hopping module 3 at the transmitting end through the mixer module 4 at the transmitting end. Finally, it is transmitted to free space through the antenna module 5 at the transmitting end.

[0094] Signal reception steps: The receiving antenna module 6 transmits the received radio frequency signal to the receiving mixer module 7, and performs down-conversion modulation on the receiving mixer module 7 with the frequency hopping frequency obtained by the receiving frequency hopping module 8. After signal processing such as intermediate frequency filtering by the receiving intermediate frequency filter 9, the original baseband signal is obtained in the receiving baseband signal module 10.

[0095] Thus, the frequency hopping anti-interference communication system based on chaotic random numbers has completed frequency hopping communication.

[0096] This invention improves the security of the communication system by combining random channel selection and chaotic channel selection in the frequency hopping module, thereby enabling information transmission without pre-sharing of the initial seed.

[0097] Those skilled in the art will understand that, besides implementing the system and its various devices, modules, and units provided by this invention in the form of purely computer-readable program code, the same functions can be achieved entirely through logical programming of the method steps, making the system and its various devices, modules, and units of this invention function in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers. Therefore, the system and its various devices, modules, and units provided by this invention can be considered as a hardware component, and the devices, modules, and units included therein for implementing various functions can also be considered as structures within the hardware component; alternatively, the devices, modules, and units for implementing various functions can be considered as both software modules implementing the method and structures within the hardware component.

[0098] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A frequency-hopping anti-interference communication system based on chaotic random numbers, characterized in that, include: Transmitter baseband signal module (1), used to provide the original baseband signal of the communication system; Transmitter information modulation module (2) is used to modulate the original baseband signal; Transmitter frequency hopping module (3) is used to determine the frequency of the frequency hopping channel; The transmitter mixer module (4) is used to mix the modulated signal with the frequency hopping channel frequency and perform upconversion processing. The transmitting antenna module (5) is used to transmit and transmit radio frequency signals to free space via waveguides; The receiving antenna module (6) is used to receive signals transmitted into free space by the transmitting antenna module (5); The receiver mixer module (7) is used to transmit the received signal to the receiver intermediate frequency filter (9) after downconversion by the receiver mixer. The receiver frequency hopping module (8) is used to determine the frequency of the frequency hopping channel; The receiving end intermediate frequency filter (9) is used to perform intermediate frequency filtering on the signal after downconversion by the receiving end mixer; The receiver baseband signal module (10) is used to obtain the original baseband signal transmitted from the transmitter after intermediate frequency filtering by the receiver intermediate frequency filter (9); Both the transmitter frequency hopping module (3) and the receiver frequency hopping module (8) include a random channel selection stage, a chaotic channel selection stage, and a frequency synthesizer. The transmitting end frequency hopping module (3) and the receiving end frequency hopping module (8) can exchange initial seed values ​​during the random channel selection phase and apply the initial seed value to the chaotic mapping during the chaotic channel selection phase to determine the frequency hopping channel frequency. The chaotic channel selection stage further includes inputting the initial seed value of the exchanged chaotic signal into the Lang-Kobayashi chaotic map to obtain different discrete chaotic values ​​E(t), which are then converted into chaotic integer values ​​E using the following formula. i : E i =int[(E(t) max ×10 q )] Where q is an integer, q≥3; The chaos exponent value I is obtained using the following formula. i This allows us to determine the channel number: I i =E i modN f Where, N f The modulo expression represents the total number of frequency hopping channels, where mod represents the chaotic integer value E. i Perform mod operations; After determining the channel and frequency hopping channel based on the channel table, the information is input into the frequency synthesizer.

2. The frequency hopping anti-interference communication system based on chaotic random numbers according to claim 1, characterized in that, The frequency synthesizer is used to generate the required frequency hopping channel frequency to ensure synchronization between the transmitter and receiver.

3. The frequency hopping anti-interference communication system based on chaotic random numbers according to claim 1, characterized in that, It also includes a channel table to guide the random channel selection process at the transmitter and receiver.

4. A frequency-hopping anti-interference communication method based on chaotic random numbers, based on the frequency-hopping anti-interference communication system based on chaotic random numbers as described in any one of claims 1-3, characterized in that, Includes the following steps: Preparation steps: Connect all modules in the system sequentially and set up the channel table; Frequency hopping steps: During the random channel selection phase, the transmitter and receiver select the initial seed value of the chaotic signal for channel exchange. During the chaotic channel selection phase, the same initial seed value is used to determine the frequency hopping channel frequency through chaotic mapping. The chaotic channel selection stage further includes inputting the initial seed value of the exchanged chaotic signal into the Lang-Kobayashi chaotic map to obtain different discrete chaotic values ​​E(t), which are then converted into chaotic integer values ​​E using the following formula. i : E i =int[(E(t) max ×10 q )] Where q is an integer, q≥3; The chaos exponent value I is obtained using the following formula. i This allows us to determine the channel number: I i =E i modN f Where, N f The modulo expression represents the total number of frequency hopping channels, where mod represents the chaotic integer value E. i Perform mod operations; After determining the channel and frequency hopping channel frequency based on the channel table, input the frequency synthesizer. Signal transmission steps: The baseband signal is modulated by the baseband signal module (1) at the transmitting end through the information modulation module (2) at the transmitting end, and then up-converted and modulated by the frequency hopping frequency obtained by the frequency hopping module (3) at the transmitting end through the mixer module (4) at the transmitting end, and then transmitted to free space through the antenna module (5) at the transmitting end; Signal receiving steps: The receiving antenna module (6) transmits the received radio frequency signal to the receiving mixer module (7), and the frequency hopping frequency obtained by the receiving frequency hopping module (8) is down-converted and modulated in the receiving mixer module (7). After the receiving intermediate frequency filter (9) filters the signal, the original baseband signal is obtained in the receiving baseband signal module (10).

5. The frequency hopping anti-interference communication method based on chaotic random numbers according to claim 4, characterized in that, The frequency hopping step includes synchronizing the transmitter and receiver by exchanging initial seed values ​​to maintain frequency consistency during communication.

6. The frequency hopping anti-interference communication method based on chaotic random numbers according to claim 4, characterized in that, The signal transmission step includes encoding and modulating the baseband signal at the transmitting end.

7. The frequency hopping anti-interference communication method based on chaotic random numbers according to claim 4, characterized in that, The random channel selection phase includes generating random numbers using frequency hopping modules at both the transmitter and receiver, with the center frequency of the random channel transmission being f. c =(1402+f n )MHz; Among them, f n This represents the channel frequency bandwidth corresponding to channel n; The chaotic channel selection phase includes enabling the transmitter and receiver to send and receive information on randomly selected frequencies. When the frequencies of the transmitter and receiver coincide, the transmitter and receiver exchange the initial seed value of the chaotic signal.

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