A multi-carrier DCSK communication method, device and system based on matrix index

Abstract

The application discloses a kind of multi-carrier DCSK communication methods, device and system based on matrix index, it is related to communication technical field, the scheme provided in the present application is according to index bit and modulation bit in transmitting end, index bit is used to construct index selector, index selector is used to select corresponding reconfiguration matrix combination, according to preset reconfiguration matrix set, matrix reconfiguration processing is carried out to the modulation symbol matrix after being modulated to chaotic signal;After matrix reconfiguration processing, the sending signal matrix frequency selective fading channel is sent to receiving end, the scheme of the present application is reconstructed by matrix index and signal matrix, the double encryption of multi-carrier DCSK communication information matrix based on matrix index is realized, to improve the security performance of DCSK system.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a multi-carrier DCSK communication method, apparatus and system based on matrix indexing. Background Technology

[0002] Multi-carrier DCSK, as an effective strategy for saving bit energy and increasing data rate, has been extensively studied. However, with the continuous development of wireless communication, more and more devices are connecting to the network, such as... Figure 1 The transceiver structure of the carrier DCSK scheme shown is illustrated. A traditional multi-carrier DCSK scheme can be viewed as a parallel extension of the DCSK system. This scheme utilizes subcarriers of different frequencies to carry reference signals and information-bearing signals. Specifically, each frame of transmitted symbols consists of... It consists of subcarriers of different frequencies. The chaos generator generates a length of... chaotic signals Afterwards, From frequency Subcarriers carry and serve as The reference signal for the transmission symbol. Then, the chaotic signal. The parallel bits obtained after serial-to-parallel conversion are input to the modulator, where the polarity of the chaotic signal carries the information bits. Finally, these information-carrying signals are processed by the remaining... Each subcarrier is used for transmission. After receiving the signal, the receiver uses a matched filter to separate the signals from the different carriers, obtaining reference matrices for each. and information carrying matrix Then the matrix and Perform relevant operations to obtain the decision variable matrix.

[0003] While traditional multi-carrier DCSK schemes have improved the transmission efficiency of DCSK to some extent, they still suffer from low security in frequency-selective fading channels. Summary of the Invention

[0004] This application provides a matrix index-based multi-carrier DCSK communication method, apparatus, and system to solve the technical problem of low security in existing multi-carrier DCSK schemes in frequency-selective fading channels.

[0005] To address the aforementioned technical problems, the first aspect of this application provides a multi-carrier DCSK communication method based on matrix indexing, comprising:

[0006] The transmitting end acquires a chaotic signal, an index bit, and a modulation bit, wherein the number of bits of the index bit and the modulation bit satisfies a preset logarithmic constraint relationship;

[0007] The transmitting end constructs an index selector according to the index bits and the modulation bits, the index selector being used to select a corresponding reconstruction matrix combination to perform a matrix reconstruction operation;

[0008] The transmitting end modulates the sending information bit matrix by the chaotic signal to obtain a sending signal matrix;

[0009] The transmitting end performs a matrix reconstruction processing on the sending signal matrix according to a preset reconstruction matrix set, wherein the reconstruction matrix set contains a plurality of reconstruction matrices, the number of reconstruction matrices being the same as the number of subcarriers of each frame of signal, and each row and each column of each reconstruction matrix having and only having one element being 1;

[0010] The transmitting end sends the sending signal matrix after the matrix reconstruction processing to a receiving end through a frequency selective fading channel, so that the receiving end performs a demodulation processing on a receiving signal matrix according to the reconstruction matrix set.

[0011] Preferably, the expression of the logarithmic constraint relationship is specifically:

[0012]

[0013] In the formula, is the number of bits of the index bits, is the number of bits of the modulation bits, and N is the number of subcarriers of each frame of transmission signal.

[0014] Preferably, the calculation formula of the matrix reconstruction processing is specifically:

[0015]

[0016] In the formula, is the sending signal after the matrix reconstruction processing, is the sending signal before the matrix reconstruction processing, is a full-matrix of dimension N, , is a reconstruction matrix set, represents a Kronecker product, represents a Hadamard product.

[0017] Preferably, the construction manner of the reconstruction matrix set is specifically:

[0018] A plurality of reconstruction matrices of N×N are constructed according to the number of subcarriers of the transmission signal, wherein N represents the number of subcarriers;

[0019] Each reconstruction matrix is divided into a plurality of reconstruction matrix sets according to the index bits, and a mapping between each reconstruction matrix set and the index bits is established.

[0020] Preferably, the selecting corresponding reconstruction matrix set for the matrix reconstruction processing of the sending signal matrix by using the index bits according to the preset reconstruction matrix set specifically comprises:

[0021] Filtering one reconstruction matrix set from the generated reconstruction matrix set;

[0022] Performing the matrix reconstruction processing of the sending signal matrix by using the filtered reconstruction matrix set.

[0023] Preferably, the demodulation processing of the receiving signal matrix by the receiving end according to the reconstruction matrix set specifically comprises:

[0024] The receiving end performs the demodulation processing of the receiving signal matrix according to the corresponding reconstruction demodulation calculation formula according to the reconstruction matrix set, so as to obtain the information bit recovery matrix.

[0025] Preferably, the reconstruction demodulation calculation formula specifically is:

[0026]

[0027]

[0028]

[0029] In the formula, is the information bit recovery matrix obtained by the demodulation processing, is the receiving signal matrix, is a dimension full 1 matrix, is the reconstruction matrix set, represents the sum by column, represents an additive white Gaussian noise matrix, is a channel response matrix, is the sending signal matrix Preferably, after obtaining the information bit recovery matrix, the method further comprises:

[0030] Extracting the first subcarrier data in the information bit recovery matrix as a reference signal to obtain a first signal matrix, and extracting the remaining subcarrier data in the information bit recovery matrix to obtain a second signal matrix;

[0031] Performing the cross multiplication of the second signal matrix and the transpose matrix of the first signal matrix to obtain a comprehensive signal matrix;

[0032] Demodulating the maximum values in the comprehensive signal matrix to obtain the index bits, and demodulating the maximum value of to obtain the modulation bits.

[0033] Meanwhile, the second aspect of the present application provides a multi-carrier DCSK communication device based on matrix index, comprising:

[0034] a signal acquisition unit configured to acquire, by the transmitting end, a chaotic signal, index bits and modulation bits, wherein the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship;

[0035] a transmitting information bit matrix configured to construct, by the transmitting end, an index selector according to the index bits and the modulation bits, the index selector being configured to select a corresponding reconstructed matrix combination to perform a matrix reconstruction operation;

[0036] a transmitting signal matrix generation unit configured to convert, by the transmitting end, a serial transmitting information bit sequence into a parallel transmitting information bit matrix after digital modulation, and then modulate the chaotic signal on the transmitting information bit matrix to obtain a transmitting signal matrix;

[0037] a matrix reconstruction processing unit configured to perform, by the transmitting end, matrix reconstruction processing on the transmitting signal matrix according to a preset reconstructed matrix set, wherein the reconstructed matrix set contains a plurality of reconstructed matrices, the number of reconstructed matrices is the same as the number of subcarriers of each frame of signal, and each reconstructed matrix has only one element of 1 in each row and each column;

[0038] a signal transmitting unit configured to transmit, by the transmitting end, the transmitting signal matrix after the matrix reconstruction processing to the receiving end through a frequency selective fading channel, so that the receiving end performs demodulation processing on a received signal matrix according to the reconstructed matrix set.

[0039] The third aspect of the present application provides a multi-carrier DCSK communication system based on matrix index, comprising a transmitting end and a receiving end.

[0040] The transmitting end and the receiving end each comprise a memory and a processor.

[0041] The memory in the transmitting end stores a first program code, which is configured to be read and executed by the processor in the transmitting end to implement the multi-carrier DCSK communication method based on matrix index provided in the first aspect of the present application.

[0042] The memory in the transmitting end stores a second program code, which is configured to be read and executed by the processor in the receiving end to implement the demodulation processing on the received signal matrix according to the corresponding reconstructed demodulation calculation formula in the reconstructed matrix set to obtain an information bit recovery matrix.

[0043] From the above technical solutions, the present application has the following advantages:

[0044] The scheme provided in the application is that, at the transmitting end, index bits and modulation bits are used to construct an index selector, the index selector is used to select a corresponding reconstruction matrix combination, a preset reconstruction matrix set is used to perform matrix reconstruction processing on a modulation symbol matrix modulated by a chaotic signal; and the transmitting signal matrix after the matrix reconstruction processing is sent to the receiving end through a frequency selective fading channel. The scheme provided in the application realizes the reconstruction of the signal matrix through the matrix index, realizes the double encryption of the multi-carrier DCSK communication information matrix based on the matrix index, and thus improves the security performance of the DCSK system. BRIEF DESCRIPTION OF DRAWINGS

[0045] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0046] Figure 1 A logic schematic diagram of a transmitter part of a multi-carrier DCSK communication system based on matrix index provided in the present application.

[0047] Figure 2 A logic schematic diagram of a receiver part of a multi-carrier DCSK communication system based on matrix index provided in the present application.

[0048] Figure 3 A flow schematic diagram of a multi-carrier DCSK communication method based on matrix index provided in the present application.

[0049] Figure 4 A matrix reconstruction logic schematic diagram in a multi-carrier DCSK communication method based on matrix index provided in the present application.

[0050] Figure 5 A BER performance comparison diagram of a multi-carrier DCSK communication system based on matrix reconstruction provided in the present application and a traditional multi-carrier DCSK system under an additive white Gaussian noise channel.

[0051] Figure 6 A BER performance comparison diagram of a multi-carrier DCSK communication system based on matrix reconstruction provided in the present application and a traditional multi-carrier DCSK system under a frequency selective fading channel.

[0052] Figure 7 A security performance comparison diagram of a multi-carrier DCSK communication system based on matrix reconstruction provided in the present application and a traditional multi-carrier DCSK system.

[0053] Figure 8A structure schematic diagram of a multi-carrier DCSK communication device based on matrix index is provided in the present application. DETAILED DESCRIPTION

[0054] The traditional multi-carrier DCSK scheme does improve the transmission efficiency of the DCSK scheme. However, the scheme can only obtain good bit error rate performance under the condition of flat fading channel, and the performance of the traditional multi-carrier DCSK scheme will be deteriorated under the condition of frequency selective fading channel. The specific reason is found through research: it is because the scheme uses different frequency subcarriers to carry reference signals and information carrying signals, and under the condition of frequency selective fading channel, the channel responses and delays of different frequency subcarriers are different, thereby causing the good autocorrelation between the reference signals and the information carrying signals to be destroyed. At the same time, since the reference signals are directly transmitted in the carrier, the signals are easy to be intercepted, and the security problem of the DCSK scheme is not well solved.

[0055] The embodiment of the present application provides a multi-carrier DCSK communication method, device and system based on matrix index, which is used for solving the technical problem of low security of the existing multi-carrier DCSK scheme under the condition of frequency selective fading channel.

[0056] In order to make the purposes, characteristics and advantages of the present application more obvious and easy to understand, the technical solutions in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the following described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0057] As shown in the figure, the embodiment of the present application provides a multi-carrier DCSK communication system based on matrix index, which comprises a transmitting end and a receiving end. Figure 2

[0058] The transmitting end and the receiving end both comprise a memory and a processor.

[0059] The memory in the transmitting end stores a first program code, and the first program code is used for being read and executed by the processor of the transmitting end, so as to realize a multi-carrier DCSK communication method based on matrix index provided by the present application.

[0060] The memory in the transmitting end stores a second program code, and the second program code is used for being read and executed by the processor of the receiving end, so as to realize the demodulation processing of the received signal matrix according to the corresponding reconstruction demodulation calculation formula according to the reconstruction matrix set, so as to obtain the information bit recovery matrix.

[0061] Please refer to​Figure 3 This application provides a multi-carrier DCSK communication method based on matrix indexing, comprising:

[0062] Step 101: The transmitting end acquires the chaotic signal, index bits, and modulation bits.

[0063] The number of index bits and modulation bits satisfies a preset logarithmic constraint relationship.

[0064] Step 102: The transmitter constructs an index selector based on the index bits and modulation bits. The index selector is used to select the corresponding reconstruction matrix combination to perform matrix reconstruction operation.

[0065] It should be noted that, as Figure 2 The system architecture shown is in which each frame of transmission symbols is composed of... It consists of several subcarriers. First, a chaotic signal is generated using a chaos generator. ,in , It is the length of the chaotic signal. satisfy The symbol "|" represents integer division. At the transmitting end, the total number of information bits transmitted in each frame depends on the number of index bits. and modulation bit number Total number of bits sent Being and satisfied , This indicates rounding down to the nearest integer, and C represents a combination operation. Therefore, the first... The frame transmission information matrix is ​​represented as follows ,in Then the serial information bit sequence After converting to a parallel sequence and mapping bits to symbols, the information symbol matrix is ​​obtained. ,in , This indicates a substitution operation.

[0066] Step 103: The transmitting end converts the serial transmission information bit sequence into a parallel transmission information bit matrix by digital modulation, and then the chaotic signal modulates the transmission information bit matrix to obtain the transmission signal matrix.

[0067] It should be noted that the transmitted information bit matrix obtained in the previous step... After being modulated by a chaotic signal, this matrix is ​​then combined with the reference signal matrix to form the initial transmitted signal matrix. ,in This indicates the transpose operation.

[0068] Step 104, the transmitting end performs matrix reconstruction processing on the sending signal matrix according to the preset reconstruction matrix set.

[0069] It should be noted that, in order to improve the security of the system, the initial sending information matrix is subjected to matrix reconstruction operation, and the matrix reconstruction operation logic mentioned in the embodiment can refer to Figure 4 :

[0070] The calculation formula of the matrix reconstruction processing mentioned in the embodiment is:

[0071]

[0072] In the formula, is the sending signal after matrix reconstruction processing, is the sending signal before matrix reconstruction processing, is a dimensional all-1 matrix, , is a reconstruction matrix set, denotes the Kronecker product, denotes the Hadamard product. Each subcarrier corresponds to a reconstruction matrix. Specifically, each matrix in the matrix set satisfies that there is and only one element of "1" in each row and each column, and all other elements are "0". In this way, a matrix satisfying the condition can be obtained.

[0073] More specifically, the construction method of the reconstruction matrix set mentioned in the embodiment is as follows:

[0074] According to the number of subcarriers of the transmission signal, a plurality of N×N reconstruction matrices are constructed, where N represents the number of subcarriers;

[0075] The reconstruction matrices are divided into a plurality of reconstruction matrix sets according to the number of subcarriers, and the number of reconstruction matrices included in each reconstruction matrix set corresponds to the number of subcarriers.

[0076] Further, the matrix reconstruction processing on the sending signal matrix according to the preset reconstruction matrix set specifically includes:

[0077] From the generated reconstruction matrix set, a reconstruction matrix set is selected;

[0078] The selected reconstruction matrix set is used to perform matrix reconstruction processing on the sending signal matrix.

[0079] As can be seen from Figure 4 , by matrix reconstruction, the signal of the first subcarrier is dispersed to different carriers and time, thereby effectively utilizing the diversity gain while improving the security, thereby improving the BER performance of the system in the frequency selective fading channel.

[0080] Step 105, the transmitting end sends the sending signal matrix after the matrix reconstruction processing to the receiving end through the frequency selective fading channel, so that the receiving end demodulates the received signal matrix according to the reconstruction matrix set.

[0081] It should be noted that the k-th transmission symbol is sent to the receiving end through the frequency selective multipath fading channel.

[0082] Further, the steps 101-105 described above are the implementation steps of the matrix reconstruction-based multicarrier DCSK communication method on the transmitting end side of the present application. Correspondingly, the matrix index-based multicarrier DCSK communication method provided by the present application further comprises:

[0083] Step 106, the receiving end demodulates the received signal matrix according to the corresponding reconstruction demodulation calculation formula according to the reconstruction matrix set, to obtain an information bit recovery matrix.

[0084] The demodulation calculation formula of the method is specifically:

[0085]

[0086]

[0087]

[0088] In the formula, is the information bit recovery matrix obtained by demodulation processing, is the received signal matrix, is a dimensional all-1 matrix, is the reconstruction matrix set, denotes column-wise summation, represents an additive white Gaussian noise matrix, is a channel response matrix, is a sending signal matrix.

[0089] Further, after obtaining the information bit recovery matrix, it further comprises:

[0090] extracting the first subcarrier data in the information bit recovery matrix as a reference signal to obtain a first signal matrix, and extracting the remaining subcarrier data in the information bit recovery matrix to obtain a second signal matrix;

[0091] cross-multiplying the second signal matrix and the transpose matrix of the first signal matrix to obtain a comprehensive signal matrix;

[0092] demodulating the largest value in the comprehensive signal matrix to obtain index bits, and The maximum value of the symbol is used to determine the modulated bit.

[0093] It should be noted that the channel response is assumed to remain constant over one symbol period. Therefore, the channel response can be modeled as a matrix.

[0094]

[0095] in, It is the first under multipath fading channel -The number of paths for the th subcarriers. It is the Draco function. and They represent The fading coefficient and delay of the -th path. Therefore, after the received signal passes through the matched filter, the received signal matrix can be obtained. for:

[0096]

[0097] in Represents the convolution symbol. This represents the additive white Gaussian noise matrix. The recovered signal can be obtained through matrix operations after deconstruction and reconstruction. The specific calculation process can be represented as follows:

[0098]

[0099] The above formulas show that for the receiver to recover the information bits, it needs to know the reconstruction matrix used by the transmitter, the selection method of the matrix set, and the order of the reconstruction matrices in order to complete the demodulation process. Unauthorized users cannot accurately obtain this information, which greatly improves the security of the DCSK system.

[0100] Then, The first data, which is the reference signal, is saved to the first signal matrix. The others are stored in the second signal matrix. Then and Perform the relevant calculations, the specific formulas are as follows: The comprehensive signal matrix is ​​obtained through calculation. Calculate the matrix The largest absolute value First, demodulate the values ​​to obtain the index bits, then... The maximum value of the sign is used to determine the modulation bit, and the decision rule is as follows:

[0101]

[0102] Compared with the existing multi-carrier DCSK technology, the application considers the characteristics of the frequency selective fading channel, provides a high-reliability multi-carrier DCSK communication scheme assisted by a matrix index index method, realizes double encryption through the combination of matrix reconstruction and index, and effectively improves the security performance of the DCSK system. The scheme designed in the application has performance advantages compared with the traditional multi-carrier DCSK scheme under the additive white Gaussian noise channel and the frequency selective fading channel, such as Figures 5 to 7 As shown in the above table, it is shown that the scheme designed in the application is more universal.

[0103] The above is a detailed description of an embodiment of the multi-carrier DCSK communication method based on matrix index provided by the application, and the following is a detailed description of a multi-carrier DCSK communication device based on matrix index provided by the application.

[0104] Please refer to Figure 8 The multi-carrier DCSK communication device based on matrix index provided by the application comprises:

[0105] The signal acquisition unit 201 is configured to acquire a chaotic signal, index bits and modulation bits by the transmitting end, wherein the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship;

[0106] The transmitting information bit matrix 202 is configured to construct an index selector by the transmitting end according to the index bits and the modulation bits, and the index selector is configured to select a corresponding reconstructed matrix combination to perform a matrix reconstruction operation;

[0107] The transmitting signal matrix generation unit 203 is configured to convert a serial transmitting information bit sequence into a parallel transmitting information bit matrix by digital modulation by the transmitting end, and then modulate the transmitting information bit matrix by the chaotic signal to obtain a transmitting signal matrix;

[0108] The matrix reconstruction processing unit 204 is configured to perform matrix reconstruction processing on the transmitting signal matrix according to a preset reconstruction matrix set by the transmitting end, wherein the reconstruction matrix set comprises a plurality of reconstruction matrices, the number of the reconstruction matrices is the same as the number of subcarriers of each frame of signal, and each row and each column of each reconstruction matrix has and only has one element of 1;

[0109] The signal sending unit 205 is configured to send the transmitting signal matrix subjected to the matrix reconstruction processing to the receiving end by the transmitting end through a frequency selective fading channel, so that the receiving end performs demodulation processing on a received signal matrix according to the reconstruction matrix set.

[0110] Further, it further comprises:

[0111] The signal receiving and demodulating unit 206 is configured to demodulate the received signal matrix according to the corresponding reconstruction and demodulation calculation formula based on the reconstruction matrix set, so as to obtain the information bit recovery matrix.

[0112] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the terminal, the device and the unit described above can refer to the corresponding processes in the foregoing method embodiments, which will not be repeated here.

[0113] In several embodiments provided in the present application, it should be understood that the disclosed terminal, device and method can be implemented by other manners. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units or components shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0114] The terms "first", "second", "third", "fourth" and the like (if any) in the description and the above drawings of the present application are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily limit to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0115] It should be understood that in the present application, "at least one" means one or more, and "multiple" means two or more. "And / or" is used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, "A and / or B" can represent three cases of only A, only B and A and B existing at the same time, wherein A and B can be singular or plural. The character " / " generally represents that the front and rear associated objects are in an "or" relationship. "At least one of the following" or similar expressions means any combination of these items, including single item or any combination of multiple items. For example, at least one of a, b or c can represent a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b and c can be single or multiple.

[0116] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, i.e., may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0117] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0118] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the present application essentially or the part that contributes to the prior art or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present application. The foregoing storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk, and various program code storage media.

[0119] The above-described embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A matrix index based multicarrier DCSK communication method, characterized in that, The method comprises the following steps: The transmitting end acquires a chaotic signal, index bits and modulation bits, wherein the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship, and an expression of the logarithmic constraint relationship is specifically as follows: ； wherein is the number of bits of the index bits, is the number of bits of the modulation bits, N is the number of subcarriers of the transmitted signal per frame, and C is a combinatorial operator. The transmitting end constructs an index selector according to the index bits and the modulation bits, and the index selector is used for selecting a corresponding reconstructed matrix combination to perform a matrix reconstruction operation, wherein the reconstructed matrix combination is constructed in a specific manner as follows: A plurality of N×N reconstructed matrices are constructed according to the number of subcarriers of a transmission signal, wherein N represents the number of subcarriers; Each reconstructed matrix is divided into a plurality of reconstructed matrix combinations, and a mapping between each reconstructed matrix combination and the index bits is established; The transmitting end converts a serial transmission information bit sequence into a parallel transmission information bit matrix after performing digital modulation on the serial transmission information bit sequence, and then modulates the transmission information bit matrix by using the chaotic signal to obtain a transmission signal matrix; The transmitting end performs a matrix reconstruction processing on the transmission signal matrix according to the reconstructed matrix combination selected by the index selector, wherein the reconstructed matrix combination contains a plurality of reconstructed matrices, the number of the reconstructed matrices is one more than the number of the modulation bits, and each row and each column of each reconstructed matrix has only one element being 1; The transmitting end sends the transmission signal matrix subjected to the matrix reconstruction processing to the receiving end through a frequency selective fading channel, so that the receiving end performs a demodulation processing on a received signal matrix according to the reconstructed matrix combination.

2. The matrix index based multicarrier DCSK communication method according to claim 1, characterized in that, The calculation formula of the matrix reconstruction processing is specifically as follows: ； wherein is the transmitted signal after matrix reconstruction processing, is the transmitted signal before matrix reconstruction processing, is a chaotic signal, is a is an all-one matrix of dimension , is the length of the chaotic signal, is the combination of reconstruction matrices, denotes the Kronecker product, denotes the Hadamard product.

3. The matrix index based multicarrier DCSK communication method according to claim 1, characterized in that, The matrix reconstruction processing on the transmission signal matrix according to the corresponding reconstructed matrix combination selected by the index bits according to the preset reconstructed matrix combination specifically comprises the following steps: One reconstructed matrix combination is selected from the generated reconstructed matrix combinations; The transmission signal matrix is subjected to the matrix reconstruction processing by using the selected reconstructed matrix combination.

4. The matrix index based multicarrier DCSK communication method according to claim 1, characterized in that, The demodulation processing of the received signal matrix according to the reconstructed matrix combination specifically comprises the following steps: The receiving end performs a demodulation processing on the received signal matrix according to the corresponding reconstructed demodulation calculation formula of the reconstructed matrix combination, so as to obtain an information bit recovery matrix.

5. The matrix index based multicarrier DCSK communication method according to claim 4, characterized in that, The reconstructed demodulation calculation formula is specifically as follows: ； ； ； wherein is a demodulation processing obtained information bit recovery matrix, is a received signal matrix, is a is a full 1 matrix of dimension is a reconstruction matrix combination, denotes a column-wise summation, denotes an additive white Gaussian noise matrix, is a channel response matrix, is the transmitted signal matrix, is the number of paths of the -th subcarrier in a multipath fading channel, is the Dirac function, and denote the -th path's fading coefficient and delay, respectively.

6. The matrix index based multicarrier DCSK communication method according to claim 4, characterized in that, After obtaining the information bit recovery matrix, the following steps are further included: The first subcarrier data in the information bit recovery matrix is extracted as a reference signal to obtain a first signal matrix, and the remaining subcarrier data in the information bit recovery matrix is extracted to obtain a second signal matrix; The second signal matrix and the transpose matrix of the first signal matrix are cross-multiplied to obtain a comprehensive signal matrix. The one with the largest absolute value in the composite signal matrix Demodulate the values ​​to obtain the index bits, and then... The maximum value of the symbol is used to determine the modulated bit.

7. A matrix index based multicarrier DCSK communication device, characterized in that, The method comprises the following steps: A signal acquisition unit is configured to acquire, by a transmitting end, a chaotic signal, index bits and modulation bits, wherein the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship, and an expression of the logarithmic constraint relationship is specifically as follows: ； wherein is the number of bits of the index bits, is the number of bits of the modulation bits, N is the number of subcarriers of the transmitted signal per frame, and C is a combinatorial operator. The transmitting information bit matrix is used for constructing an index selector by the transmitting end according to the index bit and the modulation bit, the index selector is used for selecting a corresponding reconstruction matrix combination to perform a matrix reconstruction operation, and the reconstruction matrix combination is constructed in the following manner: a plurality of N×N reconstruction matrices are constructed according to the number of subcarriers of a transmission signal, wherein N represents the number of subcarriers; and each reconstruction matrix is divided into a plurality of reconstruction matrix combinations according to the index bit, and a mapping between each reconstruction matrix combination and the index bit is established; The transmitting signal matrix generating unit is used for converting a serial transmitting information bit sequence into a parallel transmitting information bit matrix after digital modulation by the transmitting end, and then modulating the transmitting information bit matrix by the chaotic signal to obtain a transmitting signal matrix; The matrix reconstruction processing unit is used for performing a matrix reconstruction processing on the transmitting signal matrix according to a preset reconstruction matrix combination by the transmitting end, wherein the reconstruction matrix combination contains a plurality of reconstruction matrices, the number of reconstruction matrices is the same as the number of subcarriers of each frame signal, and each row and each column of each reconstruction matrix has only one element of 1; The signal transmitting unit is used for transmitting the transmitting signal matrix after the matrix reconstruction processing to the receiving end through a frequency selective fading channel by the transmitting end, so that the receiving end performs a demodulation processing on a receiving signal matrix according to the reconstruction matrix combination.

8. A matrix index based multicarrier DCSK communication system, characterized in that, Comprise: A transmitting end and a receiving end; Both the transmitting end and the receiving end comprise a memory and a processor; The memory in the transmitting end stores a first program code, the first program code is used for being read and executed by the processor in the transmitting end, and the first program code is used for implementing the matrix index-based multicarrier DCSK communication method in claim 1; The memory in the receiving end stores a second program code, the second program code is used for being read and executed by the processor in the receiving end, and the second program code is used for implementing the demodulation processing on the receiving signal matrix according to the corresponding reconstruction demodulation calculation formula according to the reconstruction matrix combination, so as to obtain an information bit recovery matrix.

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