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

Abstract

The invention discloses a multi-carrier DCSK communication method, device and system based on matrix indexing.According to the scheme, an index selector is constructed at a transmitting end according to index bits and modulation bits, the index bits are used for constructing an index selector, the index selector is used for selecting a corresponding reconstruction matrix combination, and according to a preset reconstruction matrix set, the modulation bits are used for modulating the modulation bits; matrix reconstruction processing is carried out on a modulation symbol matrix after chaos signal modulation; the sending signal matrix frequency selective fading channel after the matrix reconstruction processing is sent to a receiving end, the scheme of the invention realizes the dual encryption of the multi-carrier DCSK communication information matrix based on the matrix index through the matrix index and the reconstruction of the signal matrix, thereby improving the safety performance of the DCSK system.

Description

Technical Field

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

[0002] As an effective strategy for saving bit energy and increasing data rate, multi-carrier DCSK has been widely studied. However, with the continuous development of wireless communication, more and more devices are accessing the network, such as Figure 1 For the transceiver structure of the carrier DCSK scheme shown, the traditional multi-carrier DCSK scheme can be regarded as a parallel extension of the DCSK system. This scheme uses sub-carriers of different frequencies to carry reference signals and information-bearing signals. Specifically, each frame of transmitted symbols consists of sub-carriers of different frequencies. After the chaos generator generates a chaotic signal with a length of the is carried by the sub-carrier with a frequency of and used as the reference signal of the transmission symbol. Then, the chaotic signal and the parallel bits obtained after serial-to-parallel conversion are input into the modulator, and the polarity of the chaotic signal is used to carry information bits. Finally, these information-bearing signals are transmitted by the remaining sub-carriers. After receiving the signal, the receiving end uses a matched filter to separate the signals of different carriers, and obtains the reference matrix and the information-bearing matrix respectively. Then, the matrices and are subjected to a correlation operation to obtain a decision variable matrix. For the traditional multi-carrier DCSK scheme, although it improves the transmission efficiency of the DCSK scheme to a certain extent, this scheme still has the technical problem of low security in a frequency-selective fading channel.

[0003] For the traditional multi-carrier DCSK scheme, although it improves the transmission efficiency of the DCSK scheme to a certain extent, this scheme still has the technical problem of low security in a frequency-selective fading channel. Summary of the Invention

[0004] The present application provides a multi-carrier DCSK communication method, apparatus, and system based on matrix indexing, which is used to solve the technical problem of low security existing in the existing multi-carrier DCSK scheme in a frequency-selective fading channel.

[0005] To solve the above technical problem, a first aspect of the present application provides a multi-carrier DCSK communication method based on matrix indexing, including:

[0006] The transmitting end obtains a chaotic signal, index bits, and modulation bits, where the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship;

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

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

[0009] The transmitting end performs matrix reconstruction processing on the transmitted signal matrix according to a preset reconstruction matrix set, where the reconstruction matrix set includes a plurality of reconstruction matrices, the number of reconstruction matrices is the same as the number of subcarriers of each frame of signal, and there is only one element equal to 1 in each row and each column of each reconstruction matrix;

[0010] The transmitting end sends the transmitted signal matrix after matrix reconstruction processing through a frequency-selective fading channel to the receiving end, so that the receiving end demodulates the received 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 transmitted signal.

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

[0015]

[0016] In the formula, is the transmitted signal after matrix reconstruction processing, is the transmitted signal before matrix reconstruction processing, is an N-dimensional all-ones matrix, , is the reconstruction matrix set, represents the Kronecker product, represents the Hadamard product.

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

[0018] According to the number of subcarriers of the transmitted signal, several N×N reconstruction matrices are constructed, where N represents the number of subcarriers;

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

[0020] Preferably, according to a preset set of reconstruction matrices, using the index bits to select the corresponding set of reconstruction matrices to perform matrix reconstruction processing on the transmission signal matrix specifically includes:

[0021] Select a set of reconstruction matrices from the generated sets of reconstruction matrices;

[0022] Perform matrix reconstruction processing on the transmission signal matrix through the selected set of reconstruction matrices.

[0023] Preferably, the receiving end performing demodulation processing on the received signal matrix according to the set of reconstruction matrices specifically includes:

[0024] The receiving end performs demodulation processing on the received signal matrix according to the set of reconstruction matrices according to the corresponding reconstruction demodulation calculation formula to obtain an information bit recovery matrix.

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

[0026]

[0027]

[0028]

[0029] 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 set of reconstruction matrices, represents summing by column, represents an additive white Gaussian noise matrix, is the channel response matrix, is the transmission signal matrix. Preferably, after obtaining the information bit recovery matrix, it further includes:

[0030] Extract the data of the first sub - carrier in the information bit recovery matrix as a reference signal to obtain a first signal matrix, and extract the data of the remaining sub - carriers in the information bit recovery matrix to obtain a second signal matrix;

[0031] Perform a cross - multiplication of the second signal matrix and the transposed matrix of the first signal matrix to obtain a comprehensive signal matrix;

[0032] Demodulate the values with the largest absolute values in the comprehensive signal matrix to obtain index bits, and perform a decision on the sign of the maximum value of to obtain modulation bits.

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

[0034] A signal acquisition unit, configured to acquire a chaotic signal, index bits, and modulation bits from a transmitting end, 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 an index selector from the transmitting end according to the index bits and modulation bits, and the index selector is used to select a corresponding reconstructed matrix combination to perform matrix reconstruction operations;

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

[0037] A matrix reconstruction processing unit, configured to perform matrix reconstruction processing on the transmitted signal matrix by the transmitting end according to a preset set of reconstruction matrices, wherein the set of reconstruction matrices includes a plurality of reconstruction matrices, the number of reconstruction matrices is the same as the number of sub-carriers of each frame of signal, and there is exactly one element equal to 1 in each row and each column of each reconstruction matrix;

[0038] A signal transmission unit, configured to transmit the transmitted signal matrix after matrix reconstruction processing through a frequency-selective fading channel from the transmitting end to the receiving end, so that the receiving end demodulates the received signal matrix according to the set of reconstruction matrices.

[0039] A third aspect of the present application provides a multi-carrier DCSK communication system based on matrix indexing, including: a transmitting end and a receiving end;

[0040] Both the transmitting end and the receiving end include: a memory and a processor;

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

[0042] The memory in the transmitting end stores second program code, and the second program code is used to be read and executed by the processor of the receiving end to demodulate the received signal matrix according to the set of reconstruction matrices according to the corresponding reconstruction demodulation calculation formula to obtain an information bit recovery matrix.

[0043] It can be seen from the above technical solutions that the present application has the following advantages:

[0044] The solution provided by this application constructs an index selector at the transmitter end according to index bits and modulation bits. The index selector is used to select a corresponding reconstructed matrix combination. According to a preset set of reconstructed matrices, matrix reconstruction processing is performed on the modulated symbol matrix after being modulated by a chaotic signal; the transmitted signal matrix after matrix reconstruction processing is sent to the receiver through a frequency-selective fading channel. The solution of this application realizes the reconstruction of the signal matrix through matrix indexing, and realizes double encryption of the multi-carrier DCSK communication information matrix based on matrix indexing, thereby improving the security performance of the DCSK system. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0046] Figure 1 It is a logic schematic diagram of the transmitter end part in a multi-carrier DCSK communication system based on matrix indexing provided by this application.

[0047] Figure 2 It is a logic schematic diagram of the receiver part in a multi-carrier DCSK communication system based on matrix indexing provided by this application.

[0048] Figure 3 It is a flowchart of a multi-carrier DCSK communication method based on matrix indexing provided by this application.

[0049] Figure 4 It is a logic schematic diagram of matrix reconstruction in a multi-carrier DCSK communication method based on matrix indexing provided by this application.

[0050] Figure 5 It is a comparison chart of the BER performance between the multi-carrier DCSK communication system based on matrix reconstruction provided by this application and the traditional multi-carrier DCSK system in an additive white Gaussian noise channel.

[0051] Figure 6 It is a comparison chart of the BER performance between the multi-carrier DCSK communication system based on matrix reconstruction provided by this application and the traditional multi-carrier DCSK system in a frequency-selective fading channel.

[0052] Figure 7 It is a comparison chart of the security performance between the multi-carrier DCSK communication system based on matrix reconstruction provided by this application and the traditional multi-carrier DCSK system.

[0053] Figure 8Schematic diagram of a multi - carrier DCSK communication device based on matrix indexing provided by this application. Detailed implementation manners

[0054] Traditional multi - carrier DCSK schemes do improve the transmission efficiency of the DCSK scheme. However, this scheme can only achieve good bit - error rate performance under flat - fading channel conditions, while the performance of the traditional multi - carrier DCSK scheme will deteriorate under frequency - selective fading channels. After research, the specific reason is found that: since this scheme uses sub - carriers with different frequencies to carry reference signals and information - bearing signals, under the conditions of a frequency - selective fading channel, due to the different channel responses and delays of sub - carriers with different frequencies, the good autocorrelation between the reference signal and the information - bearing signal is destroyed. At the same time, since the reference signal is directly transmitted in the carrier, the signal is easily intercepted, and the security problem of the DCSK scheme is not well solved.

[0055] The embodiments of this application provide a multi - carrier DCSK communication method, device, and system based on matrix indexing, which are used to solve the technical problem of low security existing in the existing multi - carrier DCSK scheme in a frequency - selective fading channel.

[0056] To make the invention purpose, features, and advantages of this application more obvious and understandable, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the embodiments described below are only a part of the embodiments of this application, rather than all the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.

[0057] As Figure 2 shown, a multi - carrier DCSK communication system based on matrix indexing provided in this embodiment includes: a transmitting end and a receiving end;

[0058] Both the transmitting end and the receiving end include: a memory and a processor;

[0059] The memory in the transmitting end stores first program code, and the first program code is used to be read and executed by the processor of the transmitting end to implement a multi - carrier DCSK communication method as provided by this application;

[0060] The memory in the transmitting end stores second program code, and the second program code is used to be read and executed by the processor of the receiving end to demodulate the received signal matrix according to the corresponding reconstruction demodulation calculation formula based on the reconstruction matrix set to obtain an information bit recovery matrix.

[0061] Please refer toFigure 3 , a multi - carrier DCSK communication method based on matrix indexing provided by this application includes:

[0062] Step 101, the transmitter obtains a chaotic signal, index bits, and modulation bits.

[0063] Among them, the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship.

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

[0065] It should be noted that, as Figure 2 shown in the system architecture, in this system, each frame of transmitted symbols is composed of sub - carriers. First, a chaotic signal is generated by a chaotic generator , where , is the length of the chaotic signal, satisfies , "|" represents the integer division symbol. At the transmitter, the total number of information bits sent in each frame depends on the number of index bits and the number of modulation bits . The total number of transmitted bits is and satisfies , represents rounding down, and C is the combination operation. Therefore, the information matrix sent in the th frame is represented as , where . Then the serial information bit sequence is converted into a parallel sequence, and after bit - to - symbol mapping, the information symbol matrix is obtained, where , represents the permutation operation.

[0066] Step 103, the transmitter converts the serial transmitted information bit sequence into a parallel transmitted information bit matrix through digital modulation, and then modulates the transmitted information bit matrix with the chaotic signal to obtain a transmitted signal matrix.

[0067] It should be noted that, based on the transmitted information bit matrix obtained in the previous step, after this matrix is modulated by the chaotic signal, it forms an initial transmitted signal matrix with the reference signal matrix, where represents the transpose operation.

[0068] Step 104: The transmitting end performs matrix reconstruction processing on the transmitted signal matrix according to a preset set of reconstruction matrices.

[0069] It should be noted that in order to improve the security of the system, matrix reconstruction operation is performed on the initial transmitted information matrix. The matrix reconstruction operation logic mentioned in this embodiment can be referred to Figure 4 :

[0070] The matrix reconstruction processing mentioned in this embodiment, its calculation formula is specifically:

[0071]

[0072] In the formula, is the transmitted signal after matrix reconstruction processing, is the transmitted signal before matrix reconstruction processing, is a dimensional all - 1 matrix, , is the set of reconstruction matrices, represents the Kronecker product, represents the Hadamard product. Among them, each sub - carrier corresponds to a reconstruction matrix. Specifically, each matrix in this matrix set satisfies that there is exactly one element that is "1" in each row and each column, and all other elements are "0". By analogy, matrices that meet this condition can be obtained.

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

[0074] According to the number of sub - carriers of the transmission signal, several N×N reconstruction matrices are constructed, where N represents the number of sub - carriers;

[0075] The respective reconstruction matrices are divided into several sets of reconstruction matrices according to the number of sub - carriers. The number of reconstruction matrices included in each set of reconstruction matrices corresponds to the number of sub - carriers.

[0076] Furthermore, performing matrix reconstruction processing on the transmitted signal matrix according to a preset set of reconstruction matrices specifically includes:

[0077] Select a set of reconstruction matrices from the generated sets of reconstruction matrices;

[0078] Perform matrix reconstruction processing on the transmitted signal matrix through the selected set of reconstruction matrices.

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

[0080] Step 105: The transmitting end sends the transmitted signal matrix after matrix reconstruction processing through the frequency-selective fading channel to the receiving end, 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 above steps 101 to 105 are the implementation steps of the multi-carrier DCSK communication method based on matrix reconstruction on the transmitting end side of this application. Correspondingly, the multi-carrier DCSK communication method based on matrix indexing provided by this application further includes:

[0083] Step 106: The receiving end demodulates the received signal matrix according to the reconstruction matrix set according to the corresponding reconstruction demodulation calculation formula to obtain the 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-ones matrix, is the reconstruction matrix set, represents summing by column, represents the additive white Gaussian noise matrix, is the channel response matrix, is the transmitted signal matrix.

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

[0090] Extract the data of the first subcarrier in the information bit recovery matrix as the reference signal to obtain the first signal matrix, and extract the data of the remaining subcarriers in the information bit recovery matrix to obtain the second signal matrix;

[0091] Perform a cross product of the second signal matrix and the transposed matrix of the first signal matrix to obtain the combined signal matrix;

[0092] Demodulate the values with the largest absolute values in the combined signal matrix to obtain the index bits. The symbol of the maximum value is judged to obtain the modulated bit.

[0093] It should be noted that it is assumed that the channel response remains unchanged within one symbol period. Thus, the channel response can be modeled in a matrix form

[0094]

[0095] where is the number of paths of the -th subcarrier in the multipath fading channel, is the Dirac function, and represent the fading coefficient and delay of the -th path respectively. Therefore, after the received signal passes through the matched filter, the received signal matrix is:

[0096]

[0097] where represents the convolutional symbol, represents the additive Gaussian white noise matrix. The restored signal can be obtained through the operation of solving the reconstruction matrix, and the specific operation process can be expressed as

[0098]

[0099] It can be found from the above formula that for the receiving end to restore the information bit, it is necessary to know the reconstruction matrix used at the transmitting end, the selection method of the matrix set, and the order of the reconstruction matrix to complete the demodulation process at the receiving end, while illegal users cannot accurately obtain this information, which greatly improves the security of the DCSK system.

[0100] Then, the first data of , that is, the reference signal, is saved to the first signal matrix , and the others are saved to the second signal matrix . Then, and are subjected to a correlation operation, and the operation formula is specifically as follows: . Through the operation, the comprehensive signal matrix is obtained. Calculate the absolute value largest values in the matrix to first demodulate the index bits, and then judge the symbol of the maximum value of to obtain the modulated bits. The judgment rule is as follows:

[0101]

[0102] Compared with the existing multi - carrier DCSK technology, considering the characteristics of the frequency - selective fading channel, this application provides a high - reliability multi - carrier DCSK communication scheme assisted by a matrix index method, which realizes double encryption through the combination of matrix reconstruction and indexing, thus effectively improving the security performance of the DCSK system. The scheme designed in this application has performance advantages compared with the traditional multi - carrier DCSK scheme in both additive white Gaussian noise channels and frequency - selective fading channels, as Figures 5 to 7 shown in

[0103] This indicates that the scheme designed in this application is more universal. The above is a detailed description of an embodiment of a multi - carrier DCSK communication method based on matrix index provided by this application. The following is a detailed description of a multi - carrier DCSK communication device based on matrix index provided by this application.

[0104] Please refer to Figure 8 , a multi - carrier DCSK communication device based on matrix index provided by this application includes:

[0105] A signal acquisition unit 201, configured to acquire a chaotic signal, index bits, and modulation bits from a transmitter, where the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship;

[0106] A transmitted information bit matrix 202, configured to construct an index selector at the transmitter according to the index bits and the modulation bits, and the index selector is used to select a corresponding reconstructed matrix combination to perform matrix reconstruction operations;

[0107] A transmitted signal matrix generation unit 203, configured to convert a serial transmitted information bit sequence into a parallel transmitted information bit matrix through digital modulation at the transmitter, and then modulate the transmitted information bit matrix with a chaotic signal to obtain a transmitted signal matrix;

[0108] A matrix reconstruction processing unit 204, configured to perform matrix reconstruction processing on the transmitted signal matrix at the transmitter according to a preset set of reconstruction matrices, where the set of reconstruction matrices includes multiple reconstruction matrices, the number of reconstruction matrices is the same as the number of sub - carriers of each frame of signal, and there is exactly one element equal to 1 in each row and each column of each reconstruction matrix;

[0109] A signal transmission unit 205, configured to transmit the transmitted signal matrix after matrix reconstruction processing through a frequency - selective fading channel from the transmitter to the receiver, so that the receiver demodulates the received signal matrix according to the set of reconstruction matrices.

[0110] Furthermore, it further includes:

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

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

[0113] In several embodiments provided in the present application, it should be understood that the disclosed terminal, device, and method can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the shown or discussed mutual coupling or direct coupling or communication connection can be through some interfaces, and the indirect coupling or communication connection of the device or unit can be in an electrical, mechanical, or other form.

[0114] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above drawings are used to distinguish similar objects, and do not have to be used to describe a specific order or sequence. It should be understood that such data 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 "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not have to be limited to those steps or units clearly listed, but may 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 (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally means that the associated objects before and after are in an "or" relationship. "At least one (one) of the following" or a similar expression means any combination of these items, including any combination of single item (one) or plural items (ones). For example, at least one (one) of a, b, or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0116] The unit described as a separation component may or may not be physically separated. The component displayed as a unit may or may not be a physical unit, that is, it may be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0117] In addition, each functional unit in various embodiments of the present application may be integrated in a processing unit, or each unit may exist physically alone, or two or more units may be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0118] If the above-mentioned integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present application. The foregoing storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks, or optical discs that can store program codes.

[0119] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some 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 various embodiments of the present application.

Claims

1. A multi - carrier DCSK communication method based on matrix indexing, characterized in that Including: The transmitting end obtains a chaotic signal, index bits, and modulation bits, where the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship; The transmitting end constructs an index selector according to the index bits and modulation bits, and the index selector is used to select a corresponding reconstruction matrix combination to perform matrix reconstruction operations; The transmitting end digitally modulates a serial transmitted information bit sequence and then converts it into a parallel transmitted information bit matrix, and then the chaotic signal modulates the transmitted information bit matrix to obtain a transmitted signal matrix; The transmitting end performs matrix reconstruction processing on the transmitted signal matrix according to the combination of reconstruction matrices selected by the index selector, where the reconstruction matrix set includes multiple reconstruction matrices, the number of reconstruction matrices is the number of modulation bits plus 1, and there is exactly one element equal to 1 in each row and each column of each reconstruction matrix; The transmitting end sends the transmitted signal matrix after matrix reconstruction processing through a frequency-selective fading channel to the receiving end, so that the receiving end demodulates the received signal matrix according to the reconstruction matrix set.

2. The multi-carrier DCSK communication method based on matrix index according to claim 1, characterized in that, The expression of the logarithmic constraint relationship is specifically: wherein, is the number of bits of the index bit, is the number of bits of the modulation bit, and N is the number of subcarriers of the signal transmitted per frame.

3. A multi-carrier DCSK communication method based on matrix indexing according to claim 1, characterized in that The calculation formula of the matrix reconstruction processing is specifically: wherein, is the transmitted signal after matrix reconstruction processing, is the transmitted signal before matrix reconstruction processing, is a dimensional all-ones matrix, , is the set of reconstruction matrices, represents the Kronecker product, represents the Hadamard product.

4. A multi-carrier DCSK communication method based on matrix indexing according to claim 3, characterized in that, The construction method of the reconstruction matrix set is specifically: According to the number of subcarriers of the transmitted signal, several N×N reconstruction matrices are constructed, where N represents the number of subcarriers; Each reconstruction matrix is divided into several reconstruction matrix sets, and a mapping between each reconstruction matrix set and the index bits is established.

5. A multi-carrier DCSK communication method based on matrix indexing according to claim 4, wherein, Performing matrix reconstruction processing on the transmitted signal matrix according to the preset reconstruction matrix set by using the index bits specifically includes: Selecting a reconstruction matrix set from the generated reconstruction matrix sets; Performing matrix reconstruction processing on the transmitted signal matrix through the selected reconstruction matrix set.

6. A multi-carrier DCSK communication method based on matrix indexing according to claim 1, characterized in that, The receiving end demodulating the received signal matrix according to the reconstruction matrix set specifically includes: The receiving end demodulates the received signal matrix according to the reconstruction matrix set according to the corresponding reconstruction demodulation calculation formula to obtain an information bit recovery matrix.

7. A multi-carrier DCSK communication method based on matrix indexing according to claim 6, characterized in that, The reconstruction demodulation calculation formula is specifically: Wherein, is the information bit recovery matrix obtained by demodulation processing, is the received signal matrix, is a dimensional all - one matrix, is the reconstruction matrix set, represents summation by column, represents the additive white Gaussian noise matrix, is the channel response matrix, is the transmitted signal matrix.

8. A multi-carrier DCSK communication method based on matrix indexing according to claim 6, characterized in that After obtaining the information bit recovery matrix, it further includes: 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; Performing a cross product of the second signal matrix and the transposed matrix of the first signal matrix to obtain a demodulated signal matrix; Use the values with the largest absolute values in the comprehensive signal matrix to perform demodulation to obtain index bits, and perform a decision on the sign of the maximum value of to obtain modulation bits.

9. A multi-carrier DCSK communication device based on matrix indexing, characterized in that, Including: A signal acquisition unit, configured to obtain a chaotic signal, index bits, and modulation bits by the transmitting end, where the number of bits of the index bits and the modulation bits satisfies a preset logarithmic constraint relationship; A transmitted information bit matrix, configured to construct an index selector by the transmitting end according to the index bits and modulation bits, and the index selector is used to select a corresponding reconstruction matrix combination to perform matrix reconstruction operations; A transmission signal matrix generation unit, which is used for the transmitting end to convert a serial transmitted information bit sequence into a parallel transmitted information bit matrix after digital modulation, and then modulate the transmitted information bit matrix with the chaotic signal to obtain a transmission signal matrix; A matrix reconstruction processing unit, which is used for the transmitting end to perform matrix reconstruction processing on the transmission signal matrix according to a preset reconstruction matrix set, wherein the reconstruction matrix set includes a plurality of reconstruction matrices, the number of reconstruction matrices is the same as the number of subcarriers of each frame of signal, and there is exactly one element equal to 1 in each row and each column of each reconstruction matrix; A signal transmission unit, which is used for the transmitting end to transmit the transmission signal matrix after matrix reconstruction processing through a frequency-selective fading channel to the receiving end, so that the receiving end demodulates the received signal matrix according to the reconstruction matrix set.

10. A multi - carrier DCSK communication system based on matrix indexing, characterized in that, Comprising: A transmitting end and a receiving end; Both the transmitting end and the receiving end include a memory and a processor; The memory in the transmitting end stores first program code, which is used to be read and executed by the processor of the transmitting end to implement a multi-carrier DCSK communication method based on matrix indexing as described in claim 1; The memory in the transmitting end stores second program code, which is used to be read and executed by the processor of the receiving end to demodulate the received signal matrix according to the reconstruction matrix set according to the corresponding reconstruction demodulation calculation formula to obtain an information bit recovery matrix.

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