Chaotic communication sensing integrated signal processing method, device and communication system

Abstract

The invention discloses a chaos communication and perception integrated signal processing method and device and a communication system, and the method comprises the steps: segmenting an information bit sequence into a modulation bit sequence, an index bit sequence and a PPM bit sequence, and carrying out the processing of an initial signal vector through the combination of a pulse position modulation technology, according to the scheme, the frequency spectrum utilization rate is optimized through dual control of modulation bits and index bits, initial modulation signals are segmented according to PPM orders, signal vectors are generated, time domain offset is carried out on the signal vectors in combination with a shift matrix, the good self-correlation characteristic and the low cross-correlation characteristic of LFM signals are utilized, on the basis of an original DCSK-LFM modulation mode, the frequency spectrum utilization rate is improved, and the frequency spectrum utilization rate is improved. And in combination with pulse position modulation and index modulation, the same carrier can bear more information, so that the transmission rate when the method is applied to a JRC system and the overall performance of a communication system are improved.

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a signal processing method, device and communication system integrating chaos communication and perception. Background Art

[0002] Chaotic signals are widely used in spread spectrum communications due to their quasi-randomness, ease of generation, and good autocorrelation and cross-correlation. Currently, research on chaotic communication primarily focuses on chaotic digital communication. Among all chaos-based communication systems, incoherent chaotic communication schemes that do not require chaotic synchronization have garnered increasing attention. Differential Chaos Shift Keying (DCSK) is a prime example of such systems.

[0003] In recent years, due to the limited and fixed nature of radio spectrum resources, the exponential growth in spectrum demand for commercial communications has placed additional pressure on radar applications, forcing radar and communications to share spectrum. At the same time, wireless communications and radar sensing systems are becoming increasingly similar in hardware architecture (such as high frequency bands and antenna arrays), channel characteristics, and signal processing. The boundaries between these two systems are becoming increasingly blurred, leading to the integration of radar and communications functions into a single system, forming the foundation of Joint Radar and Communication (JRC) technology.

[0004] Although the existing DCSK-LFM technology can be directly used in the JRC system, there is a common technical problem of low data transmission rate in actual application scenarios. Summary of the Invention

[0005] The present application provides a signal processing method, device and communication system integrating chaos communication and perception, which are used to solve the technical problem of low data transmission rate when the existing DCSK-LFM technology is used in the JRC system.

[0006] To solve the above technical problems, the first aspect of the present application provides a signal processing method integrating chaos communication and perception, which is applied to a transmitter terminal, comprising:

[0007] Obtaining chaotic signals and information bit sequences;

[0008] Performing bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence, respectively, wherein the index bit sequence is used to determine a carrier as an information-bearing signal;

[0009] Performing signal modulation according to the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal;

[0010] Based on the initial modulated signal and in combination with preset PPM modulation order information, the initial modulated signal is divided into a plurality of information-bearing signal segments, and then based on each of the information-bearing signal segments, an initial signal vector corresponding to the initial modulated signal is obtained;

[0011] According to the PPM bit sequence, combined with a preset shift matrix, the initial signal vector is pulse-position modulated to obtain an information-bearing signal;

[0012] The information-bearing signal is integrated with a reference signal to obtain a transmission signal, wherein the reference signal is specifically generated based on the chaotic signal.

[0013] Preferably, performing bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence respectively comprises:

[0014] According to a preset bit sequence segmentation amount threshold, the information bit sequence is segmented to obtain a modulation bit sequence, an index bit sequence and a PPM bit sequence in sequence, wherein the number of sequence elements contained in the modulation bit sequence, the index bit sequence and the PPM bit sequence matches the bit sequence segmentation amount threshold.

[0015] Preferably, performing pulse position modulation on the initial signal vector according to the PPM bit sequence in combination with a preset shift matrix to obtain the information-bearing signal includes:

[0016] Determining a target shift matrix corresponding to the PPM bit corresponding to the initial modulated signal according to a preset correspondence between the PPM bit and the shift matrix;

[0017] The initial signal vector is pulse-position modulated according to the target shift matrix to obtain an information-bearing signal.

[0018] Preferably, the calculation formula of the initial modulation signal is specifically:

[0019]

[0020] Where, is the initial modulation signal at time t, x i is the chaotic signal, β is the spreading factor, μ is the chirp slope, T c For each chaotic signal chip period, T p is the pulse repetition period, b m is the mth element of the index bit sequence, a mis the mth element of the modulated bit sequence.

[0021] A second aspect of the present application provides a signal processing method integrating chaos communication and perception, which is applied to a receiver terminal and includes:

[0022] In response to a received signal, performing signal decomposition on the received signal to obtain a reference signal and an information-bearing signal, wherein the received signal is a signal sent by a transmitter terminal to the receiver terminal;

[0023] Dividing the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, so as to obtain a reference signal vector according to each of the reference signal segments;

[0024] Perform pulse position inverse modulation on the reference signal vector and a preset shift matrix to obtain a demodulation reference signal;

[0025] multiplying the information-bearing signal with the demodulation reference signal and the demodulation reference conjugate signal respectively to obtain a first product value and a second product value, and then calculating the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable;

[0026] A first decision variable and a second decision variable are calculated based on the first initial decision variable and the second initial decision variable, and then a demodulation result of the modulated bit sequence of the information-bearing signal is determined based on a comparison result of the first decision variable and the second decision variable, wherein the first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

[0027] Preferably, the calculation expression of the demodulation result of the modulated bit sequence is specifically:

[0028]

[0029]

[0030] Where, 、 、 are the demodulation judgment results of the mth element of the modulation bit sequence, index bit sequence and PPM bit sequence respectively, The first decision variable and the second decision variable The output of the argmax function.

[0031] Preferably, the calculation formula of the demodulation reference signal is specifically:

[0032]

[0033] Where, is the demodulation reference signal, is the reference signal vector, is the Qth shift matrix, and Q is the PPM modulation order.

[0034] A third aspect of the present application provides a signal processing device integrating chaos communication and perception, which is applied to a transmitter terminal and includes:

[0035] A basic signal acquisition unit, used for acquiring chaotic signals and information bit sequences;

[0036] a bit sequence segmentation unit, configured to perform bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence, wherein the index bit sequence is used to determine a carrier as an information-bearing signal;

[0037] An initial modulation unit, configured to perform signal modulation according to the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal;

[0038] a signal vector generating unit, configured to divide the initial modulated signal into a plurality of information-bearing signal segments based on the initial modulated signal and in combination with preset PPM modulation order information, and then obtain an initial signal vector corresponding to the initial modulated signal based on each of the information-bearing signal segments;

[0039] a pulse position modulation unit, configured to perform pulse position modulation on the initial signal vector according to the PPM bit sequence in combination with a preset shift matrix to obtain an information-bearing signal;

[0040] A transmission signal generating unit is used to integrate the information-bearing signal and a reference signal to obtain a transmission signal, wherein the reference signal is specifically generated based on the chaotic signal.

[0041] A fourth aspect of the present application provides a signal processing device integrating chaos communication and perception, which is applied to a receiver terminal and includes:

[0042] a signal receiving response unit, configured to perform signal decomposition on a received signal in response to a received signal to obtain a reference signal and an information-bearing signal, wherein the received signal is a signal sent by a transmitter terminal to the receiver terminal;

[0043] a reference signal vector decomposition unit, configured to divide the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, so as to obtain a reference signal vector according to each of the reference signal segments;

[0044] a pulse position demodulation unit, configured to perform pulse position inverse modulation on the reference signal vector and a preset shift matrix to obtain a demodulation reference signal;

[0045] an initial decision variable determining unit, configured to multiply the information-bearing signal by the demodulation reference signal and the demodulation reference conjugate signal, respectively, to obtain a first product value and a second product value, and then calculate the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable;

[0046] a modulation bit demodulation unit, configured to calculate a first decision variable and a second decision variable based on the first initial decision variable and the second initial decision variable, and then determine a demodulation result of the modulation bit sequence of the information-bearing signal based on a comparison result of the first decision variable and the second decision variable, wherein the first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

[0047] A fifth aspect of the present application provides a chaotic communication system, comprising: a transmitter terminal and a receiver terminal, wherein the transmitter terminal and the receiver terminal are communicatively connected;

[0048] The transmitter terminal includes: a first memory and a first processor, the first memory storing a first program code, the program code being used to implement a signal processing method for integrating chaos communication and perception as provided in the first aspect of the present application, and the first processor being used to read and execute the first program code;

[0049] The receiver terminal includes: a second memory and a second processor, the second memory stores a second program code, the program code is used to implement a signal processing method for integrating chaos communication and perception as provided in the second aspect of the present application, and the second processor is used to read and execute the second program code.

[0050] It can be seen from the above technical solutions that this application has the following advantages:

[0051] The solution provided in this application utilizes the good autocorrelation characteristics and low cross-correlation characteristics of the LFM signal. By dividing the information bit sequence into a modulation bit sequence, an index bit sequence and a PPM bit sequence, the initial signal vector is processed in combination with pulse position modulation technology. The spectrum utilization is optimized through dual control of the modulation bit and the index bit. The initial modulated signal is segmented according to the PPM order and a signal vector is generated. The signal vector is time-domain shifted in combination with a shift matrix. Additional information bits are transmitted through pulse position modulation and index modulation, so that the same carrier can carry more information, thereby improving the transmission rate and the overall performance of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0053] Figure 1 This is the architectural block diagram of a traditional DCSK-LFM transmitter.

[0054] Figure 2 This is the architectural block diagram of a traditional DCSK-LFM receiver.

[0055] Figure 3 This is a flow chart of an embodiment of a signal processing method for integrating chaos communication and perception applied on the transmitter side provided in this application.

[0056] Figure 4 This is a logical block diagram of an embodiment of a signal processing method for integrating chaos communication and perception applied on the transmitter side provided in this application.

[0057] Figure 5 This is a flow chart of an embodiment of a signal processing method for integrating chaos communication and perception applied on the receiver side provided by this application.

[0058] Figure 6 This is a logical block diagram of an embodiment of a signal processing method for integrating chaos communication and perception applied on the receiver side provided in this application.

[0059] Figure 7 The figure compares the bit error rate performance of the proposed solution and the traditional DCSK-LFM solution under Gaussian white noise channel.

[0060] Figure 8 This is a structural diagram of an embodiment of a signal processing device for integrating chaos communication and perception applied on the transmitter side provided in this application.

[0061] Figure 9 This is a structural diagram of an embodiment of a signal processing device for integrating chaos communication and perception applied on the receiver side provided by this application. DETAILED DESCRIPTION

[0062] In traditional incoherent chaotic communication systems, when a single-carrier modulation architecture is used, the symbol transmission rate is limited by the time-frequency characteristics of the chaotic signal itself, resulting in a limit on the amount of effective information that can be carried per unit time.

[0063] The transmitter block diagram of the DCSK-LFM scheme is as follows Figure 1 As shown in Figure 2. In this system, the transmitter sends a total of N = M + 1 pulses, where M is the number of information symbols. The first pulse is used to send the reference signal, and the remaining pulses are used to send the information-bearing signal. When the transmitted bit is "1", the information-bearing signal is the same as the reference signal. When the transmitted bit is "0", the information-bearing signal is an inverted version of the reference signal. The expression for the transmitted signal S(t) is:

[0064]

[0065] Among them, x i (i = 0,1,…,β-1) is the chaotic signal, β is the spreading factor, f0 is the initial frequency, μ is the chirp slope, T c For each chaotic signal chip period, T p is the pulse repetition period, b m is the information bit, m=1,2…,M.

[0066] Figure 2 The following is a block diagram of a DCSK-LFM receiver. The principle is as follows: After the transmitted signal reaches the target, the DCSK-LFM receiver demodulates the received waveform to identify the information symbols. Furthermore, the transmitted signal is bounced back to the JRC transceiver for signal processing to obtain information such as the target's speed and distance. The received signal r(t) can be expressed as:

[0067]

[0068] where n j,i (t) (j = 0, 1, ..., M) represents the complex white Gaussian noise with zero mean and variance N0 / 2 corresponding to the (i + 1)th sub-waveform of the (j + 1)th pulse waveform. In the DCSK-LFM scheme, the first received pulse signal r0(t) is multiplied by the conjugate copy of the LFM signal. The real part of the processed signal is then taken and the resulting signal is stored as the reference signal in the matrix Then perform the same operation on the remaining pulse signals and store the results as information-carrying signals in the matrix Finally, z=A×B T Output to the detector ([·] T is a transposition operation), when the detector detects that the corresponding element is greater than "0", the corresponding modulation bit is "1", and when the detector detects that the corresponding element is less than "0", the corresponding modulation bit is "0", so the mth estimated modulation bit It can be expressed as:

[0069]

[0070] where z m is the mth element in vector z.

[0071] In JRC system applications, DCSK-LFM technology uses a fixed carrier allocation mechanism, allowing only a single bit of information to be carried via amplitude and phase modulation within each symbol period. This makes it difficult to achieve theoretical limits on bandwidth utilization and information entropy density. This static allocation of carrier resources increases the cost of maintaining signal orthogonality and further exacerbates inter-symbol interference in multipath channels, severely limiting system throughput.

[0072] In view of this, the embodiments of the present application provide a signal processing method, device and communication system integrating chaos communication perception, aiming to provide an improved DCSK-LFM (PPM-IM-DCSK-LFM) scheme based on DCSK linear frequency modulation (LFM) (DCSK-LFM) waveform, combined with pulse position modulation (PPM) and index modulation (IM), for JRC system, to solve the technical problem of low data transmission rate of the existing DCSK-LFM scheme for JRC system.

[0073] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0074] See also Figure 3 and Figure 4 The present application provides an embodiment of a signal processing method for integrated chaos communication and perception, which is applied to a transmitter terminal side. The method includes:

[0075] Step 101: Acquire a chaotic signal and an information bit sequence;

[0076] Step 102: performing bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence;

[0077] It should be noted that the modulation bit sequence contains main communication information and is used for DCSK modulation, the index bit sequence is used to determine the carrier as the information-bearing signal, and the PPM bit is used for pulse position modulation.

[0078] It should be noted that chaotic signals refer to non-periodic signals with quasi-random characteristics. Specifically, they can be realized by using signals generated by nonlinear dynamic systems, using their good autocorrelation and cross-correlation as the basis for spread spectrum, providing a basic signal source with high security and anti-interference capabilities.

[0079] Bit sequence segmentation refers to splitting the original information bit sequence into three subsequences: modulation, index, and pulse position. Specifically, a preset segmentation length threshold can be used for fixed bit width division. Parallel information transmission can be achieved by independently allocating carrier resources and modulation parameters, thereby increasing the information carrying capacity of each unit symbol.

[0080] Assume that the transmitters in this embodiment transmit pulses, where the first pulse is a reference signal generated based on the chaotic signal, which can be described as:

[0081]

[0082] in, is the chaotic signal, β is the spreading factor, is the chip period of each chaotic signal, and T is the pulse width of the LFM signal. The remaining pulses serve as information-carrying signals, and the chaotic signal is combined with the LFM signal in the same way as the DCSK-LFM scheme. The difference is that in this scheme, the information bit d is divided into three parts, of which the first part is the modulation bit d1, which is used for DCSK modulation. Before IM and PPM are performed, when the transmitted bit is "1", the information-carrying signal is the same as the reference signal; when the transmitted bit is "0", the information-carrying signal is opposite to the reference signal. The second part is the index bit d2, which is used to determine the carrier as the information-carrying signal. The third part is the PPM bit d3, which is composed of Indicates that is the PPM bit, which is determined by the PPM modulation order. For example, when the modulation order is =2, Consists of one bit; when =4, It is composed of two bits; similarly, Depend on bits.

[0083] Step 103: performing signal modulation based on the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal;

[0084] Step 104: Based on the initial modulated signal and in combination with preset PPM modulation order information, the initial modulated signal is divided into a plurality of information-bearing signal segments, and then based on each information-bearing signal segment, an initial signal vector corresponding to the initial modulated signal is obtained;

[0085] Step 105: Pulse position modulation is performed on the initial signal vector according to the PPM bit sequence and a preset shift matrix to obtain an information-bearing signal;

[0086] It should be noted that the initial modulated signal is obtained by modulating the chaotic signal with the modulation bit sequence and the index bit sequence in combination with the time-delayed signal. The time-delayed processing enhances the anti-interference capability of the signal, and the dual control optimizes the spectrum utilization. Based on the initial modulated signal and the PPM modulation order information, the initial modulated signal is divided into multiple information-carrying signal segments, and an initial signal vector is generated. The initial signal vector refers to the conversion of the time domain signal into a multidimensional vector form, which can be achieved by segmented sampling or matrix reorganization. The multidimensional offset requirements of pulse position modulation are adapted through vectorized operations to achieve multi-bit information embedding within the same carrier.

[0087] The initial signal vector is pulse-position modulated according to the PPM bit sequence and a preset shift matrix to produce an information-carrying signal. The shift matrix achieves precise signal shifting in the time domain, allowing the same carrier to carry more information. The shift matrix is a mathematical matrix that defines the pulse position shifting rules. Specifically, it can be implemented using a cyclic shift matrix or a permutation matrix. Matrix operations control the positional offsets of the signal vector elements, enabling a single carrier to carry pulse position modulated information.

[0088] After the above-mentioned related operations, the final information-bearing modulated signal is obtained.

[0089] Step 106: Integrate the information-bearing signal and the reference signal to obtain a transmit signal.

[0090] The reference signal is specifically generated based on the chaotic signal.

[0091] It should be noted that the information-bearing signal is then integrated with the reference signal generated based on the chaotic signal to form a complete transmission signal. The reference signal utilizes the synchronization characteristics of the chaotic signal to reduce the demodulation complexity at the receiving end.

[0092] This embodiment achieves a doubling of spectrum efficiency through a multi-dimensional bit segmentation and joint modulation mechanism. The information bits are decomposed into three independently controlled subsequences of modulation, index, and pulse position, which respectively control the three dimensions of carrier allocation, modulation mode, and time domain offset, so that multiple groups of information can be transmitted simultaneously in a single symbol period. A multi-carrier system is constructed by combining the time-delay orthogonal characteristics of chaotic signals, and the index bits are used to dynamically allocate carrier resources, breaking through the single-carrier limitation of traditional chaotic communications. Through the combination of pulse position modulation and vectorized processing, information layers are further superimposed in the time domain dimension to form a three-dimensional modulation structure, which significantly improves the data transmission rate without increasing the bandwidth.

[0093] Furthermore, the information bit sequence segmentation mentioned in step 102 of the present application specifically includes the following steps:

[0094] According to a preset bit sequence segmentation threshold, the information bit sequence is segmented to obtain a modulation bit sequence, an index bit sequence and a PPM bit sequence in sequence;

[0095] The number of sequence elements included in the modulation bit sequence, the index bit sequence, and the PPM bit sequence matches the bit sequence segmentation amount threshold.

[0096] It should be noted that, assuming that the bit sequence segmentation threshold M is set in this embodiment, the three generated bit subsequences all contain M elements as follows: the modulation bit d1 is composed of Indicates that , ; For index bit d2, Indicates that ,when When it is "+1", the chirp signal is selected as the carrier of the information-bearing signal (i.e. ),when When it is "-1", the chirp signal is selected as the carrier of the information-bearing signal (i.e. ). For PPM bit d3, Indicates that The PPM bits are determined by the PPM modulation order. This segmentation method ensures that the number of sequence elements contained in the modulation bit sequence, index bit sequence, and PPM bit sequence strictly matches the preset bit sequence segmentation threshold, avoiding the problem of segmentation results not matching system parameters and ensuring the stability and accuracy of subsequent signal processing.

[0097] In some embodiments, the present application further proposes determining a target shift matrix corresponding to the PPM bits corresponding to the initial modulation signal based on a preset correspondence between the PPM bits and the shift matrix; performing pulse position modulation on the initial signal vector according to the target shift matrix to obtain an information-carrying signal.

[0098] The preset correspondence can be implemented through a lookup table or mapping function, for example, by establishing a mapping table between binary PPM bit values and matrix sequence numbers. The shift matrix can adopt a cyclic shift structure, with each matrix corresponding to a specific time slot shift amount. For example, when the PPM modulation order Q=4, four different cyclic shift matrices correspond. The number of matrix elements must match the modulation order. For example, a Q-order shift matrix is a matrix group formed by cyclically right shifting a Q×Q-dimensional unit matrix. More specifically, the mapping relationship between PPM and bits is shown in Table 1:

[0099] .

[0100] The specific operation of PPM can be represented by the shift matrix Completed, including = 1, … , For example, when = 4, no. PPM bits When using The corresponding target shift matrix is Pulse position modulation is performed to obtain the An information-bearing signal can be represented as:

[0101]

[0102] in, The signal after DCSK modulation and index modulation Average share The signal vector of the segment, ,in, can be written as:

[0103]

[0104] Where, is the pulse repetition period.

[0105] Specifically, during the pulse position modulation process, the received PPM bit sequence is first matched to the corresponding shift matrix set according to a preset mapping rule. For example, when the current PPM bit value is detected as "10," the third shift matrix is selected from the pre-stored matrix library as the operator. The initial signal vector is then multiplied by this matrix to achieve a precise shift in the signal's time domain position. Through this predefined mapping mechanism, each PPM bit value is uniquely mapped to a deterministic matrix operation, eliminating the risk of phase error accumulation associated with randomly selected matrices.

[0106] As a preferred embodiment, the solution of this application is specifically implemented as follows:

[0107] A table is pre-established that maps PPM bits to shift matrices. For example, for 2-PPM modulation, a "0" bit can be set to correspond to the identity matrix, and a "1" bit can be set to correspond to the cyclic shift matrix. For 4-PPM modulation, "00," "01," "10," and "11" can be set to correspond to different degrees of cyclic shift matrices, respectively.

[0108] When performing pulse position modulation, first according to the initial modulation signal The corresponding PPM bit is searched in a preset correspondence table to determine the target shift matrix. For example, if the current PPM bit is "10", the corresponding specific cyclic shift matrix is selected as the target shift matrix.

[0109] Next, the initial signal vector is multiplied by the target shift matrix to achieve precise modulation of the pulse position. The resulting pulse position modulated signal vector is the final information-carrying signal.

[0110] Through the above technical solution, the present application realizes a unique correspondence between PPM bits and shift matrices, eliminating the uncertainty of matrix selection. This predefined mapping mechanism ensures that each PPM bit can be accurately matched to a specific shift matrix, avoiding the phase offset error that may be caused by random selection. At the same time, the target matrix is quickly locked based on a table lookup method, improving the efficiency of the modulation process. In addition, precise pulse position modulation is achieved through matrix multiplication, ensuring the accurate positioning of the signal within the time slot window. This dual matching mechanism based on preset rules effectively improves the accuracy and robustness of pulse position modulation, laying the foundation for subsequent signal demodulation and information extraction.

[0111] Finally, the final information carrying signal S1(t)~ S m (t) and S0(t) generated by the chaotic signal are integrated into the final transmission signal S(t), and the transmission signal is sent to the receiver side through the wireless channel.

[0112] Correspondingly, the present application also provides another embodiment of a signal processing method for integrating chaos communication and perception, which is applied to the receiver terminal side and corresponds to the above-mentioned method applied to the transmitter terminal side.

[0113] See also Figure 5 The signal processing method for integrating chaos communication and perception provided in this embodiment includes:

[0114] Step 201: In response to a received signal, decompose the received signal to obtain a reference signal and an information-bearing signal;

[0115] The received signal is a signal sent from the transmitter terminal to the receiver terminal;

[0116] Step 202: Divide the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, and obtain a reference signal vector according to each reference signal segment;

[0117] Step 203: perform pulse position inverse modulation on the reference signal vector and the preset shift matrix to obtain a demodulation reference signal;

[0118] Step 204: Multiply the information-bearing signal with the demodulation reference signal and the demodulation reference conjugate signal respectively to obtain a first product value and a second product value, and then calculate the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable;

[0119] Step 205: Calculate a first decision variable and a second decision variable based on the first initial decision variable and the second initial decision variable, and then determine a demodulation result of the modulated bit sequence of the information-bearing signal based on a comparison result of the first decision variable and the second decision variable.

[0120] The first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

[0121] It should be noted that if Figure 6 As shown, the main principle of the signal processing method for integrated chaos communication and perception on the receiver side provided by this embodiment is analyzed as follows: First, the receiver receives the reference signal , then Enter the pulse position modulation block for processing. Specifically, Divided equally segment, which can be expressed as , and then perform correlation operations with the shift matrix to obtain the final result ,in, for With the The result obtained by performing correlation operations on the shift matrix. This process can be expressed as:

[0122]

[0123] Afterwards, you will get Perform conjugate operation and get , then and Correlation operations are performed on the received information-bearing signals respectively. Specifically, they are multiplied and summed accordingly. This process can be expressed as:

[0124]

[0125]

[0126] or

[0127]

[0128]

[0129] Then we can get the decision variable of DCSK modulation and Then take the absolute value of the sum and square it, and finally send the result to the comparator for comparison. The demodulated bit corresponding to the result with the largest value is the one closest to the original bit. and Both are decision variables for IM and PPM.

[0130]

[0131] Based on formulas (9), (10), (13) or (11) to (13), IM bits Hedi PPM bits can be estimated as:

[0132]

[0133] From formula (12), we can see that and The value of depends on and The maximum value in .

[0134] The decision variable of the modulation bit is selected by the IM bit and the PPM bit and can be expressed as:

[0135]

[0136] in, is the final modulation bit decision variable. Finally, by comparing it with 0, the 𝑚th modulation bit can be estimated as:

[0137]

[0138] The following is an example of data rate verification based on the signal processing method for integrated chaos communication and perception provided by this application, as follows:

[0139] The transmission bits of the PPM-IM-DCSK-LFM scheme provided in this application are divided into three parts: DCSK modulation bits, IM bits, and PPM bits. When the transmitter sends N = M + 1 pulse signals, where M is the number of pulses in the information-bearing signal, and the number of modulated bits is M, the transmission rate of the modulated bits is:

[0140]

[0141] Each information-bearing signal also carries an IM bit, so the transmission rate of the IM bit is the same as the transmission rate of the modulated bit, that is:

[0142]

[0143] The number of PPM bits carried by each information-bearing signal is determined by its order and can be calculated as , then the PPM bit transmission rate is:

[0144]

[0145] Combining the bit transmission rates of the above three parts, the data transmission rate of the PPM-IM-DCSK-LFM scheme can be obtained as follows:

[0146] (20)

[0147] When M and When it approaches infinity, formula (18) can be simplified to:

[0148]

[0149] It can be seen from this that the data rate of the PPM-IM-DCSK-LFM scheme is 2 + log2 of the data rate of the DCSK-LFM scheme times.

[0150] Simulation effect comparison example: Figure 7 As shown, from Figure 7 It can be seen that under the Gaussian white noise channel, whether the PPM modulation order Q increases or the pulse number N increases, the bit error rate performance of the PPM-IM-DCSK-LFM scheme is improved to a certain extent. Specifically, when β=128 and N=5, as Q increases from 4 to 8, the bit error rate is improved at a bit error rate of 10 -5 When , the bit error rate performance is improved by about 0.7 dB. Figure 6The data also clearly shows that the PPM-IM-DCSK-LFM scheme outperforms the DCSK-LFM scheme in bit error rate performance. For example, when β = 128 and N = 5, the PPM-IM-DCSK-LFM scheme with Q = 8 achieves a 2.7dB bit error rate performance gain over the DCSK-LFM scheme. Compared to the DCSK-LFM scheme, the PPM-IM-DCSK-LFM scheme significantly improves data transmission rate. Furthermore, the PPM-IM-DCSK-LFM scheme also significantly improves bit error rate performance.

[0151] The above is a detailed description of an embodiment of a signal processing method for integrating chaos communication and perception provided by the present application. The following is a detailed description of an embodiment of a signal processing device for integrating chaos communication and perception provided by the present application.

[0152] See also Figure 8 This embodiment provides a chaotic communication and perception integrated signal processing device, which is applied to a transmitter terminal and includes:

[0153] A basic signal acquisition unit 301 is used to acquire a chaotic signal and an information bit sequence;

[0154] A bit sequence segmentation unit 302 is configured to segment the information bit sequence into a modulation bit sequence, an index bit sequence, and a PPM bit sequence, wherein the index bit sequence is used to determine a carrier as an information-bearing signal;

[0155] The initial modulation unit 303 is used to perform signal modulation according to the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal;

[0156] A signal vector generating unit 304 is configured to divide the initial modulated signal into a plurality of information-bearing signal segments based on the initial modulated signal and in combination with preset PPM modulation order information, and then obtain an initial signal vector corresponding to the initial modulated signal based on each information-bearing signal segment;

[0157] The pulse position modulation unit 305 is used to perform pulse position modulation on the initial signal vector according to the PPM bit sequence in combination with a preset shift matrix to obtain an information-bearing signal;

[0158] The transmission signal generating unit 306 is configured to integrate the information-bearing signal and the reference signal to obtain a transmission signal, wherein the reference signal is specifically generated based on the chaotic signal.

[0159] See also Figure 9 The embodiment of the present application provides a signal processing device integrating chaos communication and perception, which is applied to a receiver terminal and includes:

[0160] a signal reception response unit 401 configured to perform signal decomposition on a received signal in response to a received signal to obtain a reference signal and an information-bearing signal, wherein the received signal is a signal sent by a transmitter terminal to a receiver terminal;

[0161] The reference signal vector decomposition unit 402 is configured to divide the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, so as to obtain a reference signal vector according to each reference signal segment;

[0162] The pulse position demodulation unit 403 is configured to perform pulse position inverse modulation on the reference signal vector and the preset shift matrix to obtain a demodulation reference signal;

[0163] an initial decision variable determining unit 404, configured to multiply the information-bearing signal by the demodulation reference signal and the demodulation reference conjugate signal, respectively, to obtain a first product value and a second product value, and then calculate the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable;

[0164] The modulation bit demodulation unit 405 is used to calculate the first decision variable and the second decision variable based on the first initial decision variable and the second initial decision variable, and then determine the demodulation result of the modulation bit sequence of the information carrying signal based on the comparison result of the first decision variable and the second decision variable.

[0165] The first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

[0166] In addition, the present application also provides a chaotic communication system, comprising: a transmitter terminal and a receiver terminal, the transmitter terminal and the receiver terminal being communicatively connected;

[0167] The transmitter terminal includes: a first memory and a first processor, the first memory storing a first program code, the program code being used to implement a signal processing method for integrating chaos communication and perception according to any one of claims 1 to 4, and the first processor being used to read and execute the first program code;

[0168] The receiver terminal includes: a second memory and a second processor, the second memory stores a second program code, the program code is used to implement a signal processing method for integrating chaos communication and perception as claimed in any one of claims 5 to 7, and the second processor is used to read and execute the second program code.

[0169] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the terminals, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0170] In the several embodiments provided in this application, it should be understood that the disclosed terminals, devices, and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of units is merely a logical function division. In actual implementation, there may be other division methods, such as 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 mutual coupling or direct coupling or communication connection shown or discussed can be through some interface, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0171] The terms "first," "second," "third," "fourth," and the like (if any) in the specification of the present application and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of the present application described herein, for example, 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 inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus.

[0172] It should be understood that in this application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following items" or similar expressions refers to any combination of these items, including any combination of single items or plural items. For example, at least 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.

[0173] Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0174] In addition, the functional units in the various embodiments of the present invention may be integrated into a single processing unit, each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software functional units.

[0175] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the portion that contributes to the prior art, or all or part of the 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 can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the various embodiments of the method of the present invention. The aforementioned storage medium includes various media that can store program code, such as USB flash drives, mobile hard drives, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0176] 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A signal processing method integrating chaos communication and perception, applied to a transmitter terminal, characterized in that: include: Obtaining chaotic signals and information bit sequences; Performing bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence, respectively, wherein the index bit sequence is used to determine a carrier as an information-bearing signal; Performing signal modulation according to the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal; Based on the initial modulated signal and in combination with preset PPM modulation order information, the initial modulated signal is divided into a plurality of information-bearing signal segments, and then based on each of the information-bearing signal segments, an initial signal vector corresponding to the initial modulated signal is obtained; According to the PPM bit sequence, combined with a preset shift matrix, the initial signal vector is pulse-position modulated to obtain an information-bearing signal; The information-bearing signal is integrated with a reference signal to obtain a transmission signal, wherein the reference signal is specifically generated based on the chaotic signal.

2. The signal processing method for integrating chaos communication and perception according to claim 1 is characterized in that: Performing bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence respectively includes: According to a preset bit sequence segmentation amount threshold, the information bit sequence is segmented to obtain a modulation bit sequence, an index bit sequence and a PPM bit sequence in sequence, wherein the number of sequence elements contained in the modulation bit sequence, the index bit sequence and the PPM bit sequence matches the bit sequence segmentation amount threshold.

3. The signal processing method for integrating chaos communication and perception according to claim 1 is characterized in that: According to the PPM bit sequence, combined with a preset shift matrix, pulse position modulation is performed on the initial signal vector to obtain an information-bearing signal, including: Determining a target shift matrix corresponding to the PPM bit corresponding to the initial modulated signal according to a preset correspondence between the PPM bit and the shift matrix; The initial signal vector is pulse-position modulated according to the target shift matrix to obtain an information-bearing signal.

4. The signal processing method for integrating chaos communication and perception according to claim 1 is characterized in that: The calculation formula of the initial modulation signal is specifically: Where, is the initial modulation signal at time t, x i is the chaotic signal, β is the spreading factor, μ is the chirp slope, T c For each chaotic signal chip period, T p is the pulse repetition period, b m is the mth element of the index bit sequence, a m is the mth element of the modulated bit sequence.

5. A signal processing method integrating chaos communication and perception, applied to a receiver terminal, characterized in that: include: In response to a received signal, performing signal decomposition on the received signal to obtain a reference signal and an information-bearing signal, wherein the received signal is a signal sent by a transmitter terminal to the receiver terminal; Dividing the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, so as to obtain a reference signal vector according to each of the reference signal segments; Perform pulse position inverse modulation on the reference signal vector and a preset shift matrix to obtain a demodulation reference signal; multiplying the information-bearing signal with the demodulation reference signal and the demodulation reference conjugate signal respectively to obtain a first product value and a second product value, and then calculating the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable; A first decision variable and a second decision variable are calculated based on the first initial decision variable and the second initial decision variable, and then a demodulation result of the modulated bit sequence of the information-bearing signal is determined based on a comparison result of the first decision variable and the second decision variable, wherein the first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

6. The signal processing method for integrating chaos communication and perception according to claim 5 is characterized in that: The calculation expression of the demodulation result of the modulated bit sequence is specifically: Where, 、 、 are the demodulation judgment results of the mth element of the modulation bit sequence, index bit sequence and PPM bit sequence respectively, The first decision variable and the second decision variable The output of the argmax function.

7. The signal processing method for integrating chaos communication and perception according to claim 5 is characterized in that: The calculation formula of the demodulation reference signal is specifically: Where, is the demodulation reference signal, is the reference signal vector, is the Qth shift matrix, and Q is the PPM modulation order.

8. A signal processing device integrating chaos communication and perception, applied to a transmitter terminal, characterized in that: include: A basic signal acquisition unit, used for acquiring chaotic signals and information bit sequences; a bit sequence segmentation unit, configured to perform bit sequence segmentation on the information bit sequence to obtain a modulation bit sequence, an index bit sequence, and a PPM bit sequence, wherein the index bit sequence is used to determine a carrier as an information-bearing signal; An initial modulation unit, configured to perform signal modulation according to the modulation bit sequence and the index bit sequence in combination with the chaotic signal after time delay processing to obtain an initial modulation signal; a signal vector generating unit, configured to divide the initial modulated signal into a plurality of information-bearing signal segments based on the initial modulated signal and in combination with preset PPM modulation order information, and then obtain an initial signal vector corresponding to the initial modulated signal based on each of the information-bearing signal segments; a pulse position modulation unit, configured to perform pulse position modulation on the initial signal vector according to the PPM bit sequence in combination with a preset shift matrix to obtain an information-bearing signal; A transmission signal generating unit is used to integrate the information-bearing signal and a reference signal to obtain a transmission signal, wherein the reference signal is specifically generated based on the chaotic signal.

9. A signal processing device integrating chaos communication and perception, applied to a receiver terminal, characterized in that: include: a signal receiving response unit, configured to perform signal decomposition on a received signal in response to a received signal to obtain a reference signal and an information-bearing signal, wherein the received signal is a signal sent by a transmitter terminal to the receiver terminal; a reference signal vector decomposition unit, configured to divide the reference signal into a plurality of reference signal segments according to preset PPM modulation order information, so as to obtain a reference signal vector according to each of the reference signal segments; a pulse position demodulation unit, configured to perform pulse position inverse modulation on the reference signal vector and a preset shift matrix to obtain a demodulation reference signal; an initial decision variable determining unit, configured to multiply the information-bearing signal by the demodulation reference signal and the demodulation reference conjugate signal, respectively, to obtain a first product value and a second product value, and then calculate the sum of the first product value and the second product value in their respective time domains to obtain a first initial decision variable and a second initial decision variable; a modulation bit demodulation unit, configured to calculate a first decision variable and a second decision variable based on the first initial decision variable and the second initial decision variable, and then determine a demodulation result of the modulation bit sequence of the information-bearing signal based on a comparison result of the first decision variable and the second decision variable, wherein the first decision variable is the square of the absolute value of the first initial decision variable, and the second decision variable is the square of the absolute value of the second initial decision variable.

10. A chaotic communication system, characterized in that: include: a transmitter terminal and a receiver terminal, wherein the transmitter terminal and the receiver terminal are communicatively connected; The transmitter terminal includes: a first memory and a first processor, the first memory storing a first program code, the program code being used to implement the signal processing method for integrating chaos communication and perception according to any one of claims 1 to 4, and the first processor being used to read and execute the first program code; The receiver terminal includes: a second memory and a second processor, the second memory stores a second program code, the program code is used to implement a signal processing method for integrating chaos communication and perception as described in any one of claims 5 to 7, and the second processor is used to read and execute the second program code.

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