Earth sound signal long-distance communication method and system based on chaos sequence

Abstract

The invention discloses an earth sound signal long-distance communication method based on a chaos sequence. The method comprises the following steps: performing chaos sequence coding to obtain a cyclic shift coding signal; decoding the cyclic shift coded signal to obtain an original information sequence; and completing the remote communication of the earth sound signals based on the obtained all original information sequences. The invention further discloses a corresponding system, electronic equipment and a computer readable storage medium, the chaos real value sequence is adopted as a spreading code, the anti-interference characteristic and the excellent autocorrelation are achieved, and the multi-access interference and the bit error rate in the multi-user environment are effectively reduced; the self-correlation characteristic of the chaos sequence is used for carrying out correlation detection to ensure accurate decoding of signals, and the integrity and accuracy of information can be ensured even in a severe communication environment; by using the cyclic shift spread spectrum coding technology, the amount of information carried by each sequence is increased without increasing extra bandwidth, more information can be transmitted in the same frequency band width, and the transmission efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of wireless communications and special communications technology, and in particular to a method and system for long-distance communication of geoacoustic signals based on chaotic sequences, which are used in shallow underground application scenarios. Background Art

[0002] Mineral resources are the cornerstone of national industrial development. With the continuous growth of demand, underground mines, as the main mining sites of mineral resources, have become increasingly problematic. The operating environment of underground mines is complex and changeable, the geological structure is unstable, and there are often geological hazards such as faults and subsidence. These factors lead to frequent mine accidents. These accidents not only bring huge economic losses, but also seriously threaten the lives of miners. When a mine disaster occurs, the existing communication channels are often destroyed, resulting in the inability of underground miners to understand the accident in time, and it is difficult to get in touch with the ground after being trapped. Therefore, ensuring the timely transmission of important information is crucial for mine rescue. The applicability of traditional electromagnetic wave transmission methods is limited due to the complexity of underground media, multipath effects, and electromagnetic interference. Geoacoustic signals are gradually introduced into the mine rescue process of geological disasters due to their slow attenuation, long propagation distance, and good transmittance.

[0003] Low bit error rate and low distortion transmission are crucial in mine rescue. However, the existing technologies have the following problems:

[0004] (1) High bit error rate. The complex underground geological structure and multipath propagation effects, as well as the presence of noise and interference, lead to high bit error rates in communications. After long-distance propagation, communication signals are severely attenuated, which in turn leads to an increase in the bit error rate and even failure of normal communication. Existing solutions usually use technologies such as error correction coding to add redundant data to detect and repair some errors, but this will significantly reduce transmission efficiency. Especially in a high bit error rate environment, the error correction capability is limited and it is difficult to ensure the reliability of communication.

[0005] (2) Low transmission rate. Limited by bandwidth, attenuation and interference of geoacoustic signals when propagating underground, and bottlenecks in modulation and demodulation technology, the transmission rate is low. To increase the transmission rate, more efficient modulation technologies are usually used, such as orthogonal amplitude modulation or MIMO technology, which increases the signal's anti-interference ability and improves channel capacity to achieve faster data transmission. However, its performance will degrade in low signal-to-noise ratio environments; MIMO technology requires complex signal processing and multiple antennas, which are difficult to implement in underground environments. Summary of the invention

[0006] The purpose of the present invention is to solve the problems of high bit error rate and low transmission rate in the mine rescue process in the prior art, and to propose a method and system for long-distance communication of geoacoustic signals based on chaotic sequences.

[0007] The first aspect of the present invention is to provide a method for long-distance communication of geoacoustic signals based on chaotic sequences, comprising:

[0008] S1, performing chaotic sequence coding to obtain a cyclic shift coding signal;

[0009] S2, decoding the cyclic shift coded signal to obtain an original information sequence;

[0010] S3, based on determining that all original information sequences are obtained, completing the long-distance communication of the geoacoustic signal.

[0011] Preferably, the S1 comprises:

[0012] S11, locally generating a chaotic sequence with high complexity and randomness based on a logistic chaotic mapping equation and initial conditions and adjusting the mean of the chaotic sequence to 0 based on a probability density function;

[0013] S12, modulating the chaotic sequence based on phase modulation to generate a geoacoustic chaotic sequence with a significant autocorrelation peak and extremely sensitive to the initial value, so as to adapt to the propagation characteristics of the geoacoustic signal;

[0014] S13, binarizing the geoacoustic chaotic sequence;

[0015] S14, performing cyclic shift spread spectrum coding on the information code based on the cyclic shift characteristic of the digital binary chaotic sequence to obtain a cyclic shift coded signal; wherein the cyclic shift spread spectrum coding is a coding method that uses a pseudo-random sequence to perform cyclic shift mapping on the information code.

[0016] Preferably, the S11 includes:

[0017] (1) Generate the original chaotic sequence:

[0018] The one-dimensional Logistic chaos mapping equation is shown in formula (1):

[0019] x n+1 =μx n (1-x n )(1)

[0020] Among them, μ is the fractal parameter and μ∈[1,4]. With the change of μ, the dynamic behavior of the Logistic mapping shows obvious periodicity and chaos. According to the change law of the Lyapunov exponent of the sequence, it is known that when 3.5699456<μ≤4, it has chaotic characteristics.

[0021] Generate the original chaotic sequence {x(n)} according to formula (1), and set μ to 4 to ensure the chaotic characteristics;

[0022] (2) According to the probability density function of the original chaotic sequence, its mean is calculated to be 1 / 2. The sequence is adjusted so that its mean is 0, and the chaotic sequence {X(n)} is obtained.

[0023] Preferably, the S12 includes:

[0024] Assume that the chaotic sequence {X(n)} consists of n chips, and directly modulate the center frequency of each chip without quantizing the chaotic sequence. The center frequency of the i-th chip is expressed as formula (2):

[0025] f i =f0+BX i (2);

[0026] Where, f0 is the center frequency and B is the system bandwidth;

[0027] By modulating the chip frequency, the center frequency f of each code element is i All of them have chaotic characteristics; the chips are connected end to end to form a continuous chaotic signal, and the phase satisfies formula (3):

[0028]

[0029] Among them, 2≤i≤n, is the initial phase of the chip and τ is the pulse width of each chip;

[0030] The waveform of each chip is expressed as formula (4):

[0031]

[0032] Thus, n chip waveforms are connected end to end to form a modulated chaotic sequence as a geoacoustic chaotic sequence.

[0033] Preferably, the S13 includes:

[0034] The chaotic sequence {x k , k=0,1,…,N} takes the absolute value and then uses m-bit binary to represent it, as shown in formula (5):

[0035] x=0.b1(x)b2(x)b3(x)…b i (x)…b m (x)b i (x)∈(0,1)(5);

[0036] After all chaotic sequences are represented by m-bit binary, n bits of the m-bit binary are extracted to form a digital binary chaotic sequence.

[0037] Preferably, the S14 includes:

[0038] Using (n,k) encoding, a length of 2 k A chaotic sequence carries kbits of information; a Logistic sequence carries 2 k The transmitted information sequence a[n] is first converted from serial to parallel, and a Logistic sequence with 128 iterations is used to allow 128 cyclic shifts. The transmitted sequence a[n] is converted in groups of 7 bits. According to the completeness of the coding mapping, the binary data stream is converted into a decimal data stream N[n]. The chaotic sequence is controlled by the decimal data stream N[n] to perform cyclic shift coding. The transmitting end encodes the information into the cyclic shift version of the chaotic sequence. Each information bit corresponds to a specific cyclic shift version. The cyclic shift of the chaotic sequence is realized by the cyclic shift matrix P. The matrix P is multiplied by the chaotic sequence once, and the chaotic sequence is cyclically shifted once. The cyclic shift matrix P is shown in formula (6):

[0039]

[0040] Using P j C represents the result of cyclic shift of the chaotic sequence j times, where C is the chaotic sequence;

[0041] The chaotic sequence C is cyclically shifted N[n] times to obtain the coded spread spectrum sequence, which is expressed as formula (7):

[0042] C N[i] [n] = P N[i] C (7);

[0043] Among them, C N[i] It represents the spread spectrum sequence obtained after the chaotic sequence C is cyclically shifted N[i] times.

[0044] Preferably, S2 includes:

[0045] S21, after passing through the ground-acoustic channel, reconstructing a chaotic sequence that is synchronized with the chaotic sequence coding; wherein the synchronized chaotic sequence is generated by the same Logistic chaotic mapping and the same initial condition to ensure the accuracy of the decoding;

[0046] S22, receiving a signal, performing a series of cyclic shift operations on the signal and a locally generated chaotic sequence synchronized with the chaotic sequence coding, each shift operation corresponding to a potential signal state, and performing an autocorrelation operation comparison to measure the similarity between the chaotic sequence and the chaotic sequence synchronized with the chaotic sequence coding; based on the cyclic autocorrelation of the chaotic sequence, when the chaotic sequence after the cyclic shift operation is completely aligned with the chaotic sequence actually used by the chaotic sequence coding, the autocorrelation result will reach a maximum value;

[0047] S23, detecting the peak value of the autocorrelation to determine the cyclic shift amount used for the chaotic sequence coding, thereby decoding the original information sequence.

[0048] The second aspect of the present invention is to provide a geoacoustic signal long-distance communication system based on chaotic sequence, comprising:

[0049] A chaotic sequence coding module (101), used for performing chaotic sequence coding;

[0050] A chaotic sequence decoding module (102), used for decoding the cyclic shift coded signal to obtain an original information sequence;

[0051] The geoacoustic signal long-distance communication module (103) is used to complete the geoacoustic signal long-distance communication based on the determination of obtaining all original information sequences.

[0052] A third aspect of the present invention provides an electronic device, comprising a processor and a memory, wherein the memory stores a plurality of instructions, and the processor is configured to read the instructions and execute the method described in the first aspect.

[0053] A fourth aspect of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a plurality of instructions, and the plurality of instructions can be read by a processor and execute the method described in the first aspect.

[0054] Beneficial effects of the method and system of the present invention:

[0055] (1) The present invention uses a chaotic real-valued sequence as a spread spectrum code, which effectively reduces multiple access interference in a multi-user environment through its anti-interference characteristics and excellent autocorrelation. The randomness and unpredictability of the chaotic sequence further enhance the system's resistance to noise and interference, and significantly reduces the bit error rate compared to the prior art. At the receiving end, the autocorrelation characteristics of the chaotic sequence are used for correlation detection, ensuring accurate decoding of the signal, and ensuring the integrity and accuracy of the information even in harsh communication environments.

[0056] (2) The present invention uses cyclic shift spread spectrum coding technology. The cyclic shift of the chaotic sequence represents the information bit, which can increase the amount of information carried by each sequence without increasing the additional bandwidth. More information can be transmitted within the same bandwidth, thereby improving transmission efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the related technologies, the drawings required for use in the specific embodiments or the related technical descriptions will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 A flow chart of a method for long-distance communication of geoacoustic signals based on chaotic sequences according to an embodiment of the present invention;

[0059] Figure 2 A schematic diagram of the principle of a chaotic sequence coding module provided according to an embodiment of the present invention;

[0060] Figure 3 A schematic diagram of the principle of a chaotic sequence decoding module provided according to an embodiment of the present invention;

[0061] Figure 4 A schematic diagram of the principle of a geoacoustic signal long-distance communication system based on a chaotic sequence according to an embodiment of the present invention;

[0062] Figure 5 A structural diagram of an electronic device provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0063] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] Embodiment 1

[0067] like Figure 1 As shown, this embodiment provides a method for long-distance communication of geoacoustic signals based on chaotic sequences, comprising:

[0068] S1, performing chaotic sequence coding to obtain a cyclic shift coding signal;

[0069] As a preferred embodiment, the S1 includes:

[0070] S11, locally generating a chaotic sequence with high complexity and randomness based on a logistic chaotic mapping equation and initial conditions and adjusting the mean of the chaotic sequence to 0 based on a probability density function;

[0071] In this embodiment, the S11 includes:

[0072] (1) Generate the original chaotic sequence:

[0073] One-dimensional Logistic mapping is the simplest nonlinear differential mapping equation and is widely used in the field of secure communications. Its mathematical expression is as follows:

[0074] x n+1 =μx n (1-x n )(1)

[0075] Among them, μ is the fractal parameter and μ∈[1,4]. With the change of μ, the dynamic behavior of the Logistic mapping shows obvious periodicity and chaos. According to the change law of the Lyapunov exponent of the sequence, it is known that when 3.5699456<μ≤4, it has chaotic characteristics.

[0076] The original chaotic sequence {x(n)} is generated according to formula (1), and μ is set to 4 to ensure the chaotic characteristics.

[0077] (2) According to the probability density function of the original chaotic sequence, its mean is calculated to be 1 / 2. The sequence is adjusted so that its mean is 0, and the chaotic sequence {X(n)} is obtained.

[0078] S12, modulating the chaotic sequence based on phase modulation to generate a geoacoustic chaotic sequence with a significant autocorrelation peak and extremely sensitive to the initial value, so as to adapt to the propagation characteristics of the geoacoustic signal;

[0079] In this embodiment, the S12 includes:

[0080] Assume that the chaotic sequence {X(n)} consists of n chips, and directly modulate the center frequency of each chip without quantizing the chaotic sequence. The center frequency of the i-th chip can be expressed as formula (2):

[0081] f i =f0+BX i (2)

[0082] Among them, f0 is the center frequency and B is the system bandwidth.

[0083] By modulating the chip frequency, the center frequency f of each code element is i All have chaotic characteristics. In order to ensure the phase continuity of the chip and reduce spectrum expansion, the chips are connected end to end to form a continuous chaotic signal, and the phase satisfies formula (3):

[0084]

[0085] Among them, 2≤i≤n, is the initial phase of the chip and τ is the pulse width of each chip.

[0086] The above transformation makes the phase of the chip have chaotic characteristics, so the waveform of each chip can be expressed as formula (4):

[0087]

[0088] Thus, n chip waveforms are connected end to end to form a modulated chaotic sequence as a geoacoustic chaotic sequence.

[0089] S13, binarizing the geoacoustic chaotic sequence;

[0090] In this embodiment, S13 includes:

[0091] The chaotic sequence {x k , k=0,1,…,N} takes the absolute value and then uses m-bit binary to represent it, as shown in formula (5):

[0092] x=0.b1(x)b2(x)b3(x)…b i (x)…b m (x)b i(x)∈(0,1)(5)

[0093] After all chaotic sequences are represented by m-bit binary, n bits of the m-bit binary are extracted to form a digital binary chaotic sequence;

[0094] S14, performing cyclic shift spread spectrum coding on the information code based on the cyclic shift characteristic of the digital binary chaotic sequence to obtain a cyclic shift coded signal; wherein the cyclic shift spread spectrum coding is a coding method that uses a pseudo-random sequence to perform cyclic shift mapping on the information code.

[0095] like Figure 2 As shown, the information source is cyclically shifted after serial-to-parallel conversion, wherein the chaotic sequence generator obtains the digital binary chaotic sequence.

[0096] In this embodiment, S14 includes:

[0097] Cyclic shift spread spectrum coding is a coding method that uses a pseudo-random sequence to perform cyclic shift mapping of information codes. Using the cyclic autocorrelation of chaotic sequences, a (n, k) coding method is used, that is, a length of 2 is used. k A chaotic sequence can carry kbits of information. k cyclic shift, where k is the order of the Logistic sequence. According to the completeness of the coding mapping, each logistic sequence can carry at most kbit of information after cyclic shift coding mapping.

[0098] At the transmitting end, the transmitted information sequence a[n] is first converted from serial to parallel. The embodiment of the present invention uses a Logistic sequence that iterates 128 times, allowing 128 cyclic shifts, so the transmitted sequence a[n] will be converted in groups of 7 bits.

[0099] According to the completeness of the coding mapping, the binary data stream is converted into a decimal data stream N[n]. The decimal data stream N[n] is used to control the chaotic sequence for cyclic shift coding. The transmitter encodes the information into the cyclic shift version of the chaotic sequence. Each information bit corresponds to a specific cyclic shift version.

[0100] The cyclic shift of the chaotic sequence is realized by the cyclic shift matrix P. The matrix P is multiplied by the chaotic sequence once, and the chaotic sequence is cyclically shifted once. The cyclic shift matrix P is shown in formula (6):

[0101]

[0102] Therefore, P j C represents the result of cyclic shift of the chaotic sequence j times, where C is the chaotic sequence;

[0103] The chaotic sequence C is cyclically shifted N[n] times to obtain the coded spread spectrum sequence, which is expressed as formula (7):

[0104] C N[i] [n] = P N[i] C (7);

[0105] Among them, C N[i] It represents the spread spectrum sequence obtained after the chaotic sequence C is cyclically shifted N[i] times.

[0106] At this point, it can be seen that the transmitted information sequence has been mapped into the spread spectrum sequence through cyclic shift coding.

[0107] S2, decoding the cyclic shift coded signal to obtain an original information sequence;

[0108] As a preferred embodiment, the S2 includes:

[0109] S21, after passing through the ground-acoustic channel, reconstructing a chaotic sequence that is synchronized with the chaotic sequence coding; wherein the synchronized chaotic sequence is generated by the same Logistic chaotic mapping and the same initial condition to ensure the accuracy of the decoding;

[0110] In this embodiment, see Figure 3 ,After passing through the ground acoustic channel, the receiving end first reconstructs the chaotic ,sequence synchronized with the transmitting end. This chaotic sequence is generated by the ,same Logistic chaotic mapping and the same initial conditions to ensure ,the accuracy of decoding.

[0111] S22, receiving a signal, performing a series of cyclic shift operations on the signal and a locally generated chaotic sequence synchronized with the chaotic sequence coding, each shift operation corresponding to a potential signal state, and performing an autocorrelation operation comparison to measure the similarity between the chaotic sequence and the chaotic sequence synchronized with the chaotic sequence coding; based on the cyclic autocorrelation of the chaotic sequence, when the chaotic sequence after the cyclic shift operation is completely aligned with the chaotic sequence actually used by the chaotic sequence coding, the autocorrelation result will reach a maximum value;

[0112] In this embodiment, the receiving end uses a cyclic shift matching filter to decode by detecting the energy result of the matching output of the local reference spread spectrum sequence and the received signal. The filter performs a series of cyclic shift operations on the reconstructed chaotic sequence C, and each shift operation corresponds to a potential signal state. The correlation value between the received signal and the local chaotic sequence under different cyclic shifts is calculated to measure the similarity of the two sequences.

[0113] The received signal y can be calculated by equation (8):

[0114]

[0115] From the cyclic shift characteristics of chaotic sequences, we can know formula (9):

[0116]

[0117] The chaotic sequence C has the characteristic of cyclic shift, that is, after M cyclic shifts, C will return to the original sequence P. M C = C. From formula (9), it can be seen that when mmodM = 0, the result reaches the maximum value M. Otherwise, the result is -1.

[0118] S23, detecting the peak value of the autocorrelation to determine the cyclic shift amount used for the chaotic sequence coding, thereby decoding the original information sequence.

[0119] In this embodiment, by searching for the position where y has the maximum value, the receiving end can determine the value of m. Therefore, when and only when m=N[i], the cyclic shift matched filter output signal y takes the maximum value. Therefore, by searching for the position where y has the maximum value, N[i] can be obtained, and then N[i] can be used to restore the original information sequence a[n].

[0120] S3, based on determining that all original information sequences are obtained, completing the long-distance communication of the geoacoustic signal.

[0121] Embodiment 2

[0122] like Figure 4 As shown, this embodiment provides a geoacoustic signal long-distance communication system based on chaotic sequence, comprising:

[0123] Chaotic sequence coding module 101, used for performing chaotic sequence coding;

[0124] A chaotic sequence decoding module 102, configured to decode the cyclic shift coded signal to obtain an original information sequence;

[0125] The geoacoustic signal long-distance communication module 103 is used to complete the geoacoustic signal long-distance communication based on the determination to obtain all the original information sequences.

[0126] The present invention also provides a memory storing a plurality of instructions, wherein the instructions are used to implement the method as in the first embodiment.

[0127] like Figure 5 As shown, the present invention also provides an electronic device, including a processor 301 and a memory 302 connected to the processor 301, the memory 302 stores a plurality of instructions, and the instructions can be loaded and executed by the processor so that the processor can execute the method as in the first embodiment.

[0128] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for long-distance communication of geoacoustic signals based on chaotic sequences, characterized in that: include: S1, performing chaotic sequence coding to obtain a cyclic shift coding signal; S2, decoding the cyclic shift coded signal to obtain an original information sequence; S3, based on determining that all original information sequences are obtained, completing the long-distance communication of the geoacoustic signal.

2. According to the method of long-distance communication of geoacoustic signals based on chaotic sequence in claim 1, it is characterized in that: The S1 includes: S11, locally generating a chaotic sequence with high complexity and randomness based on a logistic chaotic mapping equation and initial conditions and adjusting the mean of the chaotic sequence to 0 based on a probability density function; S12, modulating the chaotic sequence based on phase modulation to generate a geoacoustic chaotic sequence with a significant autocorrelation peak and extremely sensitive to the initial value, so as to adapt to the propagation characteristics of the geoacoustic signal; S13, binarizing the geoacoustic chaotic sequence; S14, performing cyclic shift spread spectrum coding on the information code based on the cyclic shift characteristic of the digital binary chaotic sequence to obtain a cyclic shift coded signal; wherein the cyclic shift spread spectrum coding is a coding method that uses a pseudo-random sequence to perform cyclic shift mapping on the information code.

3. The method for long-distance communication of geoacoustic signals based on chaotic sequences according to claim 2 is characterized in that: The S11 includes: (1) Generate the original chaotic sequence: The one-dimensional Logistic chaos mapping equation is shown in formula (1): x n+1 =μx n (1-x n ) (1) Among them, μ is the fractal parameter and μ∈[1,4]. With the change of μ, the dynamic behavior of the Logistic mapping shows obvious periodicity and chaos. According to the change law of the Lyapunov exponent of the sequence, it is known that when 3.5699456<μ≤4, it has chaotic characteristics. Generate the original chaotic sequence {x(n)} according to formula (1), and set μ to 4 to ensure the chaotic characteristics; (2) According to the probability density function of the original chaotic sequence, its mean is calculated to be 1 / 2. The sequence is adjusted so that its mean is 0, and the chaotic sequence {X(n)} is obtained.

4. The method for long-distance communication of geoacoustic signals based on chaotic sequences according to claim 3 is characterized in that: The S12 includes: Assume that the chaotic sequence {X(n)} consists of n chips, and directly modulate the center frequency of each chip without quantizing the chaotic sequence. The center frequency of the i-th chip is expressed as formula (2): f i =f0+BX i (2); Where, f0 is the center frequency and B is the system bandwidth; By modulating the chip frequency, the center frequency f of each code element is i All of them have chaotic characteristics; the chips are connected end to end to form a continuous chaotic signal, and the phase satisfies formula (3): Among them, 2≤i≤n, is the initial phase of the chip and τ is the pulse width of each chip; The waveform of each chip is expressed as formula (4): Thus, n chip waveforms are connected end to end to form a modulated chaotic sequence as a geoacoustic chaotic sequence.

5. The method for long-distance communication of geoacoustic signals based on chaotic sequences according to claim 4 is characterized in that: The S13 includes: The chaotic sequence {x k , k=0,1,…,N} takes the absolute value and then uses m-bit binary to represent it, as shown in formula (5): |x|=0.b1(x)b2(x)b3(x)…b i (x)…b m (x) b i (x)∈(0,1) (5); After all chaotic sequences are represented by m-bit binary, n bits of the m-bit binary are extracted to form a digital binary chaotic sequence.

6. The method for long-distance communication of geoacoustic signals based on chaotic sequences according to claim 5, characterized in that: The S14 includes: Using (n,k) encoding, a length of 2 k A chaotic sequence carries kbits of information; a Logistic sequence carries 2 k The transmitted information sequence a[n] is first converted from serial to parallel, and a Logistic sequence with 128 iterations is used to allow 128 cyclic shifts. The transmitted sequence a[n] is converted in groups of 7 bits. According to the completeness of the coding mapping, the binary data stream is converted into a decimal data stream N[n]. The chaotic sequence is controlled by the decimal data stream N[n] to perform cyclic shift coding. The transmitting end encodes the information into the cyclic shift version of the chaotic sequence. Each information bit corresponds to a specific cyclic shift version. The cyclic shift of the chaotic sequence is realized by the cyclic shift matrix P. The matrix P is multiplied by the chaotic sequence once, and the chaotic sequence is cyclically shifted once. The cyclic shift matrix P is shown in formula (6): Using P j C represents the result of cyclic shift of the chaotic sequence j times, where C is the chaotic sequence; The chaotic sequence C is cyclically shifted N[n] times to obtain the coded spread spectrum sequence, which is expressed as formula (7): C N[i] [n]=P N[i] C (7); Among them, C N[i] It represents the spread spectrum sequence obtained after the chaotic sequence C is cyclically shifted N[i] times.

7. The method for long-distance communication of geoacoustic signals based on chaotic sequences according to claim 6, characterized in that: The S2 includes: S21, after passing through the ground-acoustic channel, reconstructing a chaotic sequence that is synchronized with the chaotic sequence coding; wherein the synchronized chaotic sequence is generated by the same Logistic chaotic mapping and the same initial condition to ensure the accuracy of the decoding; S22, receiving a signal, performing a series of cyclic shift operations on the signal and a locally generated chaotic sequence synchronized with the chaotic sequence coding, each shift operation corresponding to a potential signal state, and performing an autocorrelation operation comparison to measure the similarity between the chaotic sequence and the chaotic sequence synchronized with the chaotic sequence coding; based on the cyclic autocorrelation of the chaotic sequence, when the chaotic sequence after the cyclic shift operation is completely aligned with the chaotic sequence actually used by the chaotic sequence coding, the autocorrelation result will reach a maximum value; S23, detecting the peak value of the autocorrelation to determine the cyclic shift amount used for the chaotic sequence coding, thereby decoding the original information sequence.

8. A geoacoustic signal long-distance communication system based on chaotic sequence, used to implement the method described in any one of claims 1 to 7, characterized in that: include: A chaotic sequence coding module (101), used for performing chaotic sequence coding; A chaotic sequence decoding module (102), used for decoding the cyclic shift coded signal to obtain an original information sequence; The geoacoustic signal long-distance communication module (103) is used to complete the geoacoustic signal long-distance communication based on the determination of obtaining all original information sequences.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a plurality of instructions, and the processor is used to read the instructions and execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a plurality of instructions, and the plurality of instructions can be read by a processor to execute the method according to any one of claims 1 to 7.

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