A differential chaotic phase-shift keying waveform design method and modulation and demodulation method suitable for communication and perception integration

Abstract

This invention discloses a differential chaotic phase-shift keying waveform design method and modulation / demodulation method suitable for integrated communication and sensing. In this invention, the reference subcarrier and data subcarrier within the same subcarrier group share the same chaotic reference sequence, allowing the receiver to recover the original data using the existing OFDM-DCSK incoherent detection structure. Simultaneously, based on the Riemann matrix-based group selection mapping method, by constructing a constant complex weight vector within the group, multiple OFDM-DCSK time-domain candidate waveforms are generated and selectively transmitted without changing the OFDM-DCSK system's "reference-data equal-weight spread spectrum" structure and the receiver's incoherent demodulation method, thus achieving effective suppression of PAPR in the transmitted waveform. Using the OFDM-DCSK time-domain candidate waveforms as a unified baseband signal, incoherent communication and radar sensing functions are simultaneously realized with a single hardware and spectrum resource.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a differential chaotic phase shift keying waveform design method and modulation / demodulation method suitable for integrated communication and sensing. Background Technology

[0002] Chaotic communication refers to the introduction of chaotic sequences into a communication system to perform functions such as spread spectrum, modulation, or encryption. Chaotic sequences possess high sensitivity to initial conditions, approximately continuous power spectra, and good autocorrelation and cross-correlation properties, thus offering potential advantages in anti-interference, anti-interception, and confidentiality. Based on whether the receiver needs to recover the chaotic sequence from the transmitter, chaotic digital communication can be broadly classified into two categories: coherent chaotic communication and incoherent chaotic communication. Compared to coherent chaotic communication, incoherent chaotic communication schemes avoid strict synchronization requirements through differential or correlation detection, making them more practically feasible in complex channels and low-cost implementation scenarios. Differential Chaos Shift Keying (DCSK) is a typical incoherent chaotic modulation technique. DCSK does not require channel estimation and chaotic synchronization, has a relatively simple implementation structure, and exhibits good robustness to multipath fading and time-varying channels. To improve spectral efficiency and enhance resistance to frequency-selective fading, DCSK can be combined with Orthogonal Frequency Division Multiplexing (OFDM) to form an Orthogonal Frequency Division Multiplexing Differential Chaotic Phase Shift Keying (OFDM-DCSK) system.

[0003] With the development of 5G-Advanced and 6G technologies, the demand for simultaneously achieving high-reliability communication and high-precision environmental perception under the same hardware platform and spectrum resources is becoming increasingly prominent in scenarios such as vehicle-to-everything (V2X), autonomous driving, drone monitoring, and intelligent transportation. Integrated Sensing and Communication (ISAC) aims to significantly improve spectrum utilization, reduce system costs, and achieve closer service convergence by carrying communication data and sensing functions on a unified signal waveform and RF link. Therefore, OFDM and its evolved waveforms have received widespread attention in ISAC. However, since OFDM signals are composed of multiple mutually orthogonal subcarriers, their time-domain waveforms may have high instantaneous peak power, which is typically measured using the peak-to-average power ratio (PAPR). A high PAPR forces the transmitter power amplifier to operate under significant backoff to maintain linearity, thereby reducing energy efficiency; if the operating point enters the nonlinear region, it will cause severe waveform distortion and adjacent channel leakage, leading to an increase in the bit error rate. For ISAC systems, nonlinear distortion of the transmitted waveform can also disrupt the main lobe shape and side lobe structure of the ambiguity function, thereby reducing sensing resolution and target detection performance.

[0004] Therefore, in the design of ISAC waveforms based on OFDM-DCSK, how to effectively suppress PAPR while ensuring communication and sensing performance is an urgent problem to be solved. Summary of the Invention

[0005] This invention provides a differential chaotic phase shift keying waveform design method and modulation / demodulation method suitable for integrated communication and sensing, which solves the technical problem that existing ISAC waveform designs based on OFDM-DCSK are difficult to effectively suppress PAPR while ensuring communication and sensing performance.

[0006] This invention provides a differential chaotic phase-shift keying waveform design method suitable for integrated communication and sensing, the method comprising:

[0007] Data modulation is performed on the bit stream to be transmitted according to the preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; a chaotic signal generator is used to generate a corresponding chaotic reference sequence for each subcarrier group;

[0008] The chaotic reference sequence is mapped onto the associated reference subcarrier, and the chaotic reference sequence is multiplied with the associated data symbols to map onto the associated data subcarrier, generating OFDM-DCSK frequency domain symbol sequences of multiple subcarriers;

[0009] A Riemann matrix is ​​constructed based on the preset number of subcarrier groups. The Riemann matrix is ​​then element-modulated according to the preset number of candidate sequences to obtain a candidate weight matrix. The candidate weight matrix is ​​then expanded according to the preset total number of subcarriers to obtain a candidate subcarrier weight matrix, so that the reference subcarriers and data subcarriers in the same subcarrier group under the same candidate sequence share the same complex weights.

[0010] The OFDM-DCSK frequency domain symbol sequence is multiplied symbol by symbol with each candidate sequence in the candidate subcarrier weight matrix to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences;

[0011] An N-point IFFT is performed on each of the weighted OFDM-DCSK frequency domain symbol sequences to obtain the corresponding OFDM-DCSK time domain candidate waveform; where N is the preset total number of subcarriers;

[0012] Calculate the PAPR of each OFDM-DCSK time-domain candidate waveform, and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

[0013] Optionally, the steps of constructing a Riemann matrix based on the preset number of subcarrier groups, performing element-wise modulation on the Riemann matrix according to a preset number of candidate sequences to obtain a candidate weight matrix, and expanding the candidate weight matrix according to a preset total number of subcarriers to obtain a candidate subcarrier weight matrix include:

[0014] Based on the preset number of subcarrier groups, construct a The Riemann matrix is ​​obtained by mapping each element of the Riemann matrix to a corresponding complex weight factor to obtain a complex matrix; where... The preset number of subcarrier groups;

[0015] Row vectors are selected from the complex matrix according to a preset number of candidate sequences and their energy is normalized to form a candidate weight matrix;

[0016] The candidate subcarrier weight matrix is ​​obtained by performing an extended product operation on the candidate weight matrix according to the preset total number of subcarriers.

[0017] Optionally, the elements in the Riemann matrix are represented as follows:

[0018]

[0019] In the formula: Let be the element in the i-th row and j-th column of the Riemann matrix;

[0020] The complex weighting factors in the complex matrix are represented as follows:

[0021]

[0022] In the formula: Let be the complex weighting factor in the i-th row and j-th column of the complex matrix;

[0023] The extended product operation of the candidate weight matrix is ​​represented as follows:

[0024]

[0025] In the formula: for The candidate subcarrier weight matrix, for Candidate weight matrix, It is a row vector of length L consisting entirely of 1s; This is for Kronecker product operations.

[0026] Optionally, the step of modulating the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups includes:

[0027] The serial-to-parallel conversion of the bit stream to be transmitted is performed according to the preset number of subcarrier groups to obtain serial-to-parallel bit symbols of multiple subcarrier groups;

[0028] Each of the serial-parallel bit symbols is subjected to BPSK modulation to obtain data symbols for multiple subcarriers.

[0029] This invention also provides a differential chaotic phase shift keying modulation and demodulation method suitable for integrated communication and sensing, involving a transmitter, a communication receiver, and a radar receiver; the method includes:

[0030] The transmitter performs a parallel-to-serial conversion on the transmitted waveform generated by the transmitter according to any of the differential chaotic phase shift keying waveform design methods described above, thereby generating a transmitted signal.

[0031] The received signal is obtained by receiving the transmitted signal through the wireless channel using the communication receiver; the received signal is then subjected to non-coherent detection processing to recover the corresponding bit data.

[0032] The radar receiver receives the echo signal formed by the scattering of the transmitted signal; the echo signal is processed to obtain the distance and speed information of the transmitting target.

[0033] Optionally, the step of performing noncoherent detection processing on the received signal to recover the corresponding bit data includes:

[0034] The received signal is sequentially subjected to serial-to-parallel conversion and N-point FFT processing to obtain the received frequency domain signals corresponding to the reference subcarriers and data subcarriers of multiple sets of subcarriers;

[0035] The decision statistics for each group of subcarriers are obtained by performing conjugate correlation operations on the received frequency domain signals of the reference subcarrier and the data subcarrier in each group of subcarriers.

[0036] The decision-maker performs decision processing based on the decision statistics to obtain the corresponding decision result;

[0037] Perform parallel-to-serial conversion on all the aforementioned decision results to recover the bit data carried by each group of subcarriers.

[0038] This invention also provides a differential chaotic phase-shift keying waveform design system suitable for integrated communication and sensing, the system comprising:

[0039] The modulation unit is used to modulate the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; and a chaotic signal generator is used to generate a corresponding chaotic reference sequence for each subcarrier group.

[0040] A frequency domain symbol sequence generation unit is used to map the chaotic reference sequence onto an associated reference subcarrier, and multiply the chaotic reference sequence with an associated data symbol to map it onto an associated data subcarrier, thereby generating OFDM-DCSK frequency domain symbol sequences for multiple subcarriers;

[0041] The candidate subcarrier weight matrix construction unit is used to construct a Riemann matrix based on the preset number of subcarrier groups, perform element modulation on the Riemann matrix according to the preset number of candidate sequences to obtain a candidate weight matrix, and perform expansion processing on the candidate weight matrix according to the preset total number of subcarriers to obtain a candidate subcarrier weight matrix, so that the reference subcarriers and data subcarriers in the same subcarrier group under the same candidate sequence share the same complex weights.

[0042] The weighted frequency domain symbol sequence generation unit is used to multiply the OFDM-DCSK frequency domain symbol sequence with each candidate sequence in the candidate subcarrier weight matrix symbol by symbol to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences;

[0043] The time-domain candidate waveform generation unit is used to perform N-point IFFT processing on each of the weighted OFDM-DCSK frequency domain symbols to obtain the corresponding OFDM-DCSK time-domain candidate waveform; where N is the preset total number of subcarriers;

[0044] The transmit waveform selection unit is used to calculate the PAPR of each OFDM-DCSK time-domain candidate waveform and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

[0045] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0046] This invention also provides a computer-readable storage medium storing a computer program or instructions thereon, wherein the computer program or instructions, when executed by a processor, implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0047] This invention also provides a computer program product, including a computer program or instructions, which, when executed by a processor, implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0048] As can be seen from the above technical solutions, the present invention has the following advantages:

[0049] This invention provides a differential chaotic phase-shift keying waveform design method and modulation / demodulation method suitable for integrated communication and sensing. The differential chaotic phase-shift keying waveform design method includes: modulating the bit stream to be transmitted according to a preset number of subcarrier groups to obtain multiple groups of subcarrier data symbols; generating a corresponding chaotic reference sequence for each subcarrier group using a chaotic signal generator; mapping the chaotic reference sequence onto associated reference subcarriers, and multiplying the chaotic reference sequence with the associated data symbols to map it onto the associated data subcarriers, generating multiple groups of OFDM-DCSK frequency domain symbol sequences; constructing a Riemann matrix based on a preset number of subcarrier groups, and performing element-wise modulation on the Riemann matrix according to a preset number of candidate sequences to obtain a candidate weight matrix; and then, according to a preset total number of subcarrier groups... The candidate weight matrix is ​​expanded to obtain the candidate subcarrier weight matrix, so that the reference subcarrier and each data subcarrier in the same subcarrier group under the same candidate sequence share the same complex weight. The OFDM-DCSK frequency domain symbol sequence is multiplied symbol by symbol with each candidate sequence in the candidate subcarrier weight matrix to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences. An N-point IFFT is performed on each weighted OFDM-DCSK frequency domain symbol sequence to obtain the corresponding OFDM-DCSK time domain candidate waveform, where N is the preset total number of subcarriers. The PAPR of each OFDM-DCSK time domain candidate waveform is calculated, and the OFDM-DCSK time domain candidate waveform associated with the smallest PAPR is selected as the transmit waveform.

[0050] In this invention, the reference subcarrier and data subcarrier within the same subcarrier group share the same chaotic reference sequence, allowing the receiver to recover the original data using the existing OFDM-DCSK incoherent detection structure. Simultaneously, based on the Riemann matrix-based group selection mapping method, by constructing a constant complex weight vector within the group, multiple OFDM-DCSK time-domain candidate waveforms are generated and selectively transmitted without altering the OFDM-DCSK system's "reference-data equal-weight spread spectrum" structure and the receiver's incoherent demodulation method. This effectively suppresses PAPR of the transmitted waveform. Using the OFDM-DCSK time-domain candidate waveforms as a unified baseband signal, both incoherent communication and radar sensing functions are simultaneously achieved with a single hardware and spectrum resource. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 A flowchart illustrating the steps of a differential chaotic phase shift keying waveform design method applicable to integrated communication and sensing, provided in an embodiment of the present invention;

[0053] Figure 2 This is a structural block diagram of the OFDM-DCSK ISAC system provided in an embodiment of the present invention;

[0054] Figure 3 A data flow diagram of group selection mapping (G-SLM) based on Riemann matrices provided in an embodiment of the present invention;

[0055] Figure 4 A flowchart of steps for differential chaotic phase shift keying waveform modulation and demodulation suitable for integrated communication and sensing is provided in this embodiment of the invention.

[0056] Figure 5 (a) is the distance-Doppler ambiguity function performance diagram of the conventional OFDM-DCSK waveform provided in the embodiment of the present invention; Figure 5 (b) is the distance-Doppler ambiguity function performance diagram of the OFDM-DCSK waveform after adding G-SLM according to the embodiment of the present invention; Figure 5 (c) is the distance-Doppler ambiguity function performance diagram of the OFDM-DCSK waveform after adding ungrouped Riemann-SLM according to the embodiment of the present invention;

[0057] Figure 6PAPR performance comparison chart of existing SLM and G-SLM of this solution provided for embodiments of the present invention;

[0058] Figure 7 This is a simulation comparison chart of the communication performance of traditional systems without G-SLM and systems with G-SLM under different channels, provided for embodiments of the present invention.

[0059] Figure 8 This is a structural block diagram of a differential chaotic phase shift keying waveform design suitable for integrated communication and sensing, provided as an embodiment of the present invention. Detailed Implementation

[0060] This invention provides a differential chaotic phase shift keying waveform design method and modulation / demodulation method suitable for integrated communication and sensing, which solves the technical problem that existing ISAC waveform designs based on OFDM-DCSK are difficult to effectively suppress PAPR while ensuring communication and sensing performance.

[0061] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0062] It should be noted that, in the optional embodiments of the present invention, the data related to object information, etc., requires the permission or consent of the object when the embodiments of the present invention are applied to specific products or technologies. Furthermore, the collection, use, and processing of the relevant data must comply with the relevant laws, regulations, and standards of the relevant countries and regions. In other words, if the embodiments of the present invention involve data related to an object, it needs to be obtained with the object's authorization and consent, the authorization and consent of relevant departments, and in accordance with the relevant laws, regulations, and standards of the country and region. If the embodiments involve personal information, the acquisition of all personal information requires the individual's consent. If sensitive information is involved, the separate consent of the information subject is required. The embodiments also need to be implemented with the object's authorization and consent.

[0063] The method provided in this embodiment of the invention relates to communication. For ease of understanding, the relevant communication technologies are described below.

[0064] Differential Chaos Phase Shift Keying (DCSK) is a typical incoherent chaotic modulation technique. Its basic idea is that within each symbol period, a reference chaotic sequence is first transmitted. This chaotic sequence can be represented by a second-order Chebyshev map. Generate and set different initial values ​​for each subcarrier group; then transmit a data signal associated with the reference sequence. Let the length of each symbol period be... The reference sequence length (i.e., the spreading factor) is , No. The number of bits to be sent is Reference sequence Then the transmitter is at the 1st Discrete-time signal within one symbol period It can be represented as:

[0065]

[0066] The receiving end receives the signal Perform delay-related calculations to obtain the decision variable. :

[0067]

[0068] Finally, a sign decision is made on the decision variable with zero as the threshold.

[0069] DCSK modulation does not require channel estimation and chaotic synchronization, has a relatively simple implementation structure, and exhibits good robustness to multipath fading and time-varying channels.

[0070] To improve spectral efficiency and enhance resistance to frequency-selective fading, existing technologies combine DCSK with Orthogonal Frequency Division Multiplexing (OFDM) to form an Orthogonal Frequency Division Multiplexing Differential Chaotic Phase Shift Keying (OFDM-DCSK) system.

[0071] In an OFDM-DCSK system, all subcarriers are divided into several groups, each sharing a reference signal derived from a chaotic sequence extension. The other subcarriers within the group carry data signals associated with that reference signal. A single subcarrier containing... Baseband discrete-time signal of OFDM symbols with subcarriers It can be expressed as:

[0072]

[0073] In the formula: For the first Frequency domain symbols on each subcarrier, for a system using OFDM-DCSK It consists of a chaotic reference and its modulated data signal.

[0074] The OFDM-DCSK system, by constructing a "reference-data" structure in the frequency domain, can retain the advantages of incoherent detection while using OFDM to resist frequency-selective fading and support multi-user and high data rate transmission.

[0075] Integrated Sensing and Communication (ISAC) aims to significantly improve spectrum utilization, reduce system costs, and achieve closer service convergence by carrying communication data and sensing functions on a unified signal waveform and RF link. To evaluate the sensing performance of a waveform, an ambiguity function is typically used to characterize its range-velocity resolution and sidelobe characteristics. For one-dimensional baseband signals... Its fuzzy function The general form is:

[0076]

[0077] In the formula: For time delay, This is the Doppler frequency shift; among which, the main lobe width is related to the range / velocity resolution, while the side lobe level affects multi-target resolution and anti-jamming performance.

[0078] Furthermore, OFDM and its evolved waveforms have received considerable attention in ISAC. However, because OFDM signals are composed of multiple orthogonal subcarriers superimposed, their time-domain waveforms may exhibit high instantaneous peak power. This characteristic is typically measured using the peak-to-average power ratio (PAPR).

[0079]

[0080] High PAPR forces the transmitter power amplifier to operate under significant backoff to maintain linearity, thus reducing energy efficiency. If the operating point enters the nonlinear region, it can cause severe waveform distortion and adjacent channel leakage, leading to an increased bit error rate. For ISAC systems, nonlinear distortion of the transmitted waveform can also disrupt the main lobe shape and side lobe structure of the ambiguity function, thereby reducing sensing resolution and target detection performance. Therefore, in ISAC waveform design based on OFDM or OFDM-DCSK, effectively suppressing PAPR while ensuring communication and sensing performance is a key consideration.

[0081] In existing ISAC research, common waveform schemes mainly include radar center waveforms represented by Linear Frequency Modulation (LFM) and communication center waveforms represented by Gold Code Spread Spectrum (OFDM). Some works have also explored combined schemes such as DCSK–LFM. These schemes mostly rely on coherent processing and accurate channel estimation, are quite sensitive to synchronization and hardware conditions, and their design focus is mainly on radar performance such as range-velocity resolution and sidelobe suppression, or traditional bit error rate performance. There is insufficient consideration for the joint optimization of communication reliability, sensing performance, and low peak-to-average power ratio under the same incoherent chaotic structure, and a systematic design method suitable for OFDM-DCSK waveforms has not yet been formed.

[0082] To address the aforementioned problems, this invention provides a differential chaotic phase-shift keying waveform design method suitable for integrated communication and sensing. It uses the OFDM-DCSK waveform as a unified communication and sensing baseband signal, simultaneously achieving incoherent communication and radar sensing functions with a single hardware and spectrum resource. Furthermore, it constructs a G-SLM based on the Riemann matrix and replicates and expands the weights according to the subcarrier grouping structure, employing a frequency-domain weighting method. This effectively suppresses the peak-to-average power ratio of the transmitted waveform without altering the OFDM-DCSK reference-data correlation structure and the receiver's incoherent demodulation structure, and without transmitting any sideband information. For details, please refer to... Figure 1 This invention provides a differential chaotic phase-shift keying waveform design method suitable for integrated communication and sensing, the method comprising:

[0083] Step 101: Modulate the bit stream to be transmitted according to the preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; use a chaotic signal generator to generate a corresponding chaotic reference sequence for each subcarrier group.

[0084] Please see Figure 2 The embodiments of the present invention are applied to the OFDM-DCSK ISAC system, assuming that the system has a total of There are 1 subcarriers, and they are evenly divided into 12 subcarriers. 1 subcarrier group, each containing 1 subcarrier group Subcarriers; according to the preset number of subcarrier groups Treating the sent bit stream Perform data modulation to obtain Data symbols of group subcarriers ;in, Indicates the subcarrier group index. This indicates the data subcarrier index within the group.

[0085] Subsequently, a chaotic signal generator was used to generate a corresponding length of [length missing] for each group of subcarriers. Chaotic reference sequence Specifically, different initial values ​​are used for different subcarrier groups, and the chaotic signal generator generates different chaotic reference sequences for each group based on the second-order Chebyshev mapping to reduce inter-group correlation.

[0086] In one specific implementation, the process of modulating the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups may include the following steps:

[0087] S11. Perform serial-to-parallel conversion on the bit stream to be transmitted according to the preset number of subcarrier groups to obtain serial-to-parallel bit symbols of multiple subcarrier groups;

[0088] S12. Perform BPSK modulation on each serial-parallel bit symbol to obtain data symbols for multiple subcarriers.

[0089] In this specific embodiment, according to the preset number of subcarrier groups Treating the sent bit stream Perform serial-to-parallel transformation to obtain The serial-to-parallel bit symbols of the subcarriers are generated; the serial-to-parallel bit symbols are then subjected to BPSK modulation to obtain the corresponding data symbols. .

[0090] Step 102: Map the chaotic reference sequence onto the associated reference subcarrier, and multiply the chaotic reference sequence with the associated data symbols to map it onto the associated data subcarrier, generating OFDM-DCSK frequency domain symbol sequences of multiple subcarriers.

[0091] In this embodiment, for the first Group subcarriers, assuming Corresponding to the reference subcarrier index, the rest Indexing the data subcarriers; mapping the chaotic reference sequence onto the associated reference subcarriers to obtain the OFDM-DCSK frequency domain symbols of the reference subcarriers. Simultaneously, the same chaotic reference sequence is multiplied symbol by symbol for each data subcarrier in the group to obtain the OFDM-DCSK frequency domain symbol for each data subcarrier in the group: This results in an OFDM-DCSK frequency domain symbol sequence with a "reference-data equal weight spread spectrum" structure.

[0092] It is understood that, based on the traditional OFDM-DCSK structure, this embodiment divides all subcarriers into several subcarrier groups, sets up reference subcarriers and data subcarriers in each subcarrier group, shares the same chaotic reference sequence, and achieves incoherent detection through the "reference-data equal weight spread spectrum" structure within the group.

[0093] Step 103: Construct a Riemann matrix based on the preset number of subcarrier groups, and perform element modulation on the Riemann matrix according to the preset number of candidate sequences to obtain a candidate weight matrix; expand the candidate weight matrix according to the preset total number of subcarriers to obtain a candidate subcarrier weight matrix, so that the reference subcarriers and data subcarriers in the same subcarrier group under the same candidate sequence share the same complex weights.

[0094] It should be noted that the Selected Mapping (SLM) sequence constructed based on the traditional Riemann matrix is ​​only applicable to coherent OFDM and cannot be directly used in DCSK-ISAC. Specifically, the traditional Riemann matrix SLM method constructs multiple sets of amplitude or phase perturbation sequences, without considering the structural constraints such as "reference-data correlation" and "approximate orthogonality between groups" in OFDM-DCSK. If applied directly to OFDM-DCSK, it will disrupt the original correlation structure, destroy incoherent detection and group orthogonality, and greatly affect the ambiguity function characteristics of ISAC. Moreover, it mostly requires sideband information, affecting spectral efficiency.

[0095] Based on the structural characteristics of each group of subcarriers, this embodiment designs a Riemann matrix group selection mapping (G-SLM) method compatible with subcarriers within the group: First, a Riemann matrix is ​​constructed based on a preset number of subcarrier groups. Then, according to the preset candidate sequence number, the Riemann matrix is... Element modulation is performed to obtain the candidate weight matrix. Finally, the candidate weight matrix is ​​expanded according to the preset total number of subcarriers to obtain the candidate subcarrier weight matrix. .

[0096] In the candidate subcarrier weight matrix Within the same candidate sequence u, all subcarriers (including reference subcarriers and data subcarriers) in the same subcarrier group share the same weight parameter (i.e., complex weight). Therefore, the receiver can maintain the original incoherent detection structure without any candidate index or other sideband information during correlation demodulation.

[0097] In one specific implementation, step 103 may include the following steps:

[0098] S21. Based on the preset number of subcarrier groups, construct a... The Riemann matrix is ​​obtained by mapping each element of the Riemann matrix to the corresponding complex weight factor to obtain a complex matrix;

[0099] S22. Select row vectors from the complex matrix according to the preset number of candidate sequences and perform energy normalization to form a candidate weight matrix;

[0100] S23. Perform an extended product operation on the candidate weight matrix according to the preset total number of subcarriers to obtain the candidate subcarrier weight matrix.

[0101] Specifically, please refer to Figure 3 First, construct a Riemann matrix The elements of the Riemann matrix are represented as follows:

[0102]

[0103] In the formula: Let be the element in the i-th row and j-th column of the Riemann matrix; it can be observed from equation (6) that when the column number It is a line number When the matrix elements of the Riemann matrix are integer multiples of the matrix elements, the matrix elements of the Riemann matrix take the following Otherwise, take -1.

[0104] Subsequently, the Riemann matrix Each element in Mapped to a complex weighting factor This yields a complex matrix; the complex weighting factor contains both amplitude and phase perturbations, as shown below:

[0105]

[0106] In the formula: Let be the complex weighting factor in the i-th row and j-th column of the complex matrix; The imaginary unit is used; the mapping relationship of equation (7) ensures that the perturbation of the complex matrix acts on both the amplitude and phase, which can more effectively explore subsequent candidate signals with lower PAPR.

[0107] Next, from the mapping In a complex matrix, randomly select OK( A candidate weight matrix at the group level is constructed using a preset number of candidate sequences. Meanwhile, to ensure a fair comparison, the candidate weight matrix is ​​adjusted. Each row vector is energy normalized to satisfy:

[0108]

[0109] In the formula: Candidate weight matrix The element in the u-th row and j-th column of the array.

[0110] Due to the total number of subcarriers To ensure that all subcarriers within the same subcarrier group share the same complex weights, the candidate weight matrix needs to be expanded; specifically, this is done through Kronecker product operations. Candidate weight matrix Expand to Candidate subcarrier weight matrix ,Right now:

[0111]

[0112] In the formula: symbol Represents the Kronecker product. It is a length of A row vector consisting entirely of 1s.

[0113] In extended processing, for Candidate weight matrix Each candidate sequence is copied and rearranged according to subcarrier groups: the candidate sequence u is copied and rearranged with the first... The elements corresponding to the group are repeated. This makes all members of the group... Each subcarrier shares the same complex weight. Thus forming a length of The amplitude-phase weighted sequence of "group constant".

[0114] Step 104: Multiply the OFDM-DCSK frequency domain symbol sequence with each candidate sequence in the candidate subcarrier weight matrix symbol by symbol to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences.

[0115] In this embodiment, the symbols in the OFDM-DCSK frequency domain symbol sequence are multiplied symbol by symbol with each element in the candidate subcarrier weight matrix to obtain the weighted OFDM-DCSK frequency domain symbol sequence corresponding to U candidate sequences. Since the reference and data subcarriers in the same group experience the same complex weights, the original incoherent detection structure can be maintained without any candidate index or other sideband information during correlation demodulation at the receiver.

[0116] Step 105: Perform N-point IFFT processing on each weighted OFDM-DCSK frequency domain symbol sequence to obtain the corresponding OFDM-DCSK time domain candidate waveform.

[0117] In this embodiment, each weighted OFDM-DCSK frequency domain symbol sequence is processed by an N-point inverse fast Fourier transform (IFFT) to obtain U OFDM-DCSK time domain candidate waveforms.

[0118] Step 106: Calculate the PAPR of each OFDM-DCSK time-domain candidate waveform, and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

[0119] Understandably, the peak-to-average power ratio (PAPR) of each OFDM-DCSK time-domain candidate waveform is calculated, and the OFDM-DCSK time-domain candidate waveform with the smallest PAPR is selected as the final transmit waveform for the current symbol.

[0120] The differential chaotic phase-shift keying waveform design method for integrated communication and sensing provided by this invention has the following advantages:

[0121] 1. To address the issue that existing OFDM-DCSK schemes are only used as a communication system and do not form a unified communication and sensing integrated waveform, this invention, based on the traditional OFDM-DCSK structure, divides all subcarriers into several subcarrier groups. Within each group, a reference subcarrier and a data subcarrier are set up, sharing the same chaotic reference sequence. Incoherent detection is achieved through the "reference-data equal-weight spread spectrum" structure within the group. At the same time, the same transmitted waveform and its echo are used to complete the target's range and velocity estimation, thereby achieving communication and sensing integration under a single hardware and spectrum resource.

[0122] 2. To address the issues of high peak-to-average power (PAPR) in OFDM-DCSK waveforms and the inability of traditional Riemann matrix SLMs to be directly applied to OFDM-DCSK, this invention proposes a G-SLM method based on the Riemann matrix. A complex weighted sequence is constructed for each subcarrier group, multiplied with the OFDM-DCSK frequency domain symbols to generate multiple candidate waveforms, and the one with the lowest PAPR is selected for transmission. This method effectively reduces the PAPR of the transmitted waveform without altering the reference-data correlation structure and the receiver's incoherent detection structure, and without transmitting any sideband information. Furthermore, it has minimal impact on ambiguity function and bit error rate performance, making it suitable for integrated communication and sensing scenarios.

[0123] Please see Figure 4 This invention also provides a differential chaotic phase shift keying modulation and demodulation method suitable for integrated communication and sensing. The modulation and demodulation method involves a transmitter, a communication receiver, and a radar receiver; the method includes:

[0124] Step 201: The transmitter performs parallel-to-serial conversion on the transmitted waveform generated by the transmitter according to the differential chaotic phase shift keying waveform design method to generate the transmitted signal;

[0125] Step 202: Receive the transmitted signal through the wireless channel using a communication receiver to obtain the received signal; perform non-coherent detection processing on the received signal to recover the corresponding bit data;

[0126] Step 203: Receive the echo signal formed by the scattering of the transmitted signal through a radar receiver; perform sensing processing on the echo signal to obtain the distance and speed information of the transmitting target.

[0127] This invention is applied to the OFDM-DCSK ISAC system. Please refer to [link / reference]. Figure 2 The OFDM-DCSK ISAC system includes a transmitter, a communication receiver, and a radar receiver. At the transmitting end, the transmitter performs a parallel-to-serial conversion on the transmitted waveform generated by the differential chaotic phase shift keying waveform design method described above to generate the transmitted signal. At the receiving end, the communication receiver receives the transmitted signal through the wireless channel to obtain the received signal. The received signal undergoes incoherent detection processing to recover the corresponding bit data. Simultaneously, the radar receiver receives the echo received signal formed by the scattering of the transmitted signal. The echo received signal undergoes sensing processing to obtain the distance and velocity information of the transmitting target.

[0128] It should be noted that, since the reference subcarrier and data subcarrier in the same group undergo completely identical amplitude and phase scaling, the useful signal term and first-order noise term in differential correlation demodulation are scaled proportionally without changing the original incoherent detection structure. Under given analysis conditions and simulation range, the BER remains basically unchanged. Therefore, the receiver does not need any sideband information about the G-SLM candidate sequence to continue using the original OFDM-DCSK incoherent detection structure.

[0129] Meanwhile, the orthogonal grouping relationship between each subcarrier group is maintained, and the main lobe width and side lobe level of the ambiguity function only change slightly. This achieves a significant reduction in PAPR while largely preserving communication reliability and radar sensing performance.

[0130] In one specific implementation, step 202 may include the following steps:

[0131] S31. Perform serial-to-parallel conversion and N-point FFT processing on the received signal in sequence to obtain the received frequency domain signals corresponding to the reference subcarriers and data subcarriers of multiple subcarriers.

[0132] S32. Perform conjugate correlation operation on the received frequency domain signals of the reference subcarrier and the received frequency domain signals of the data subcarrier in each group of subcarriers to obtain the decision statistics of each group of subcarriers.

[0133] S33. The decision-making device performs decision processing based on the decision statistics to obtain the corresponding decision result;

[0134] S34. Perform parallel-to-serial conversion on all decision results to recover the bit data carried by each group of subcarriers.

[0135] At the receiving end, for the first The first in the group For each subcarrier, the communication receiver employs the traditional OFDM-DCSK incoherent detection method. Specifically, the communication receiver first performs serial-to-parallel conversion and N-point FFT processing on the received signal to convert the signal from the time domain to the frequency domain, and then performs correlation operations on the reference subcarrier and data subcarrier within each group.

[0136] Considering the received first digit under an additive white Gaussian noise (AWGN) channel. The received frequency domain signals of the reference subcarrier and the data subcarrier can be represented as follows:

[0137]

[0138]

[0139] In the formula: For the first The received frequency domain signal of the group reference subcarrier, For the first The first in the group The received frequency domain signal of each data subcarrier; The chaotic reference sequence to be sent (length is...) ); The data symbol bits to be transmitted; All are complex Gaussian noise.

[0140] The communication receiver performs conjugate correlation operations on the received frequency domain signals of the reference subcarrier and the data subcarrier to obtain the decision statistic. :

[0141]

[0142] In the formula: For the first The first in the group Decision statistics for each data subcarrier.

[0143] Specifically, substituting the received signal, which has undergone serial-to-parallel conversion and N-point FFT processing, into the above equation and expanding it, we get:

[0144]

[0145] After the receiver performs relevant calculations, complex weights are introduced into G-SLM. Statistics on judgments The effect is only reflected in the amplitude scaling of the useful signal term (i.e., the coefficient is ). While noise-related terms are also affected Modulation, but in binary decision, the receiver only relies on... Demodulate the symbols.

[0146] because The weighting factor is always a positive real number. Only change The amplitude remains unchanged, without altering its sign. This means that under ideal, noise-free conditions... The verdict and The specific value of is completely irrelevant. This mathematical property fundamentally ensures that the receiver can correctly recover the original bit information even when it is completely unaware of the G-SLM candidate sequence selected by the transmitter, thus achieving true "no sideband information required" transmission.

[0147] Compared to existing communication-sensing integrated waveforms such as LFM waveforms and Gold code spread spectrum OFDM, as well as PAPR suppression methods such as traditional Riemann matrix SLM, random phase SLM, and Partial Transmit Sequence (PTS), this invention simultaneously achieves communication-sensing integrated functionality within the same OFDM-DCSK framework. Furthermore, it effectively reduces the peak-to-average power ratio (PAPR) through G-SLM without altering the receiver structure or requiring any sideband information.

[0148] Please see Figures 5-7 The embodiments of the present invention also provide corresponding simulation experiments to verify the implementation effect of the present invention.

[0149] Please see Figure 5 Images (a)-(c) sequentially show a comparison of the distance-Doppler blur function for the three schemes: Figure 5 (a) corresponds to the traditional OFDM-DCSK waveform. Figure 5 (b) corresponds to the OFDM-DCSK waveform after adding G-SLM. Figure 5 (c) corresponds to the OFDM-DCSK waveform with ungrouped Riemann-SLM. From Figure 5 As can be seen from (a), the traditional OFDM-DCSK waveform has good sensing performance, with a sharp main lobe and low side lobes in its ambiguity function, but this scheme has the inherent defect of high PAPR. Figure 5 (b) demonstrates that after introducing the G-SLM scheme proposed in this invention, the ambiguity function characteristics of the waveform are well preserved: the main lobe width remains essentially unchanged, the side lobe level only shows a slight increase, and its integral sidelobe ratio (ISLR) remains at approximately -12 dB, indicating that the overall change in integral sidelobe energy is small. This shows that G-SLM significantly reduces PAPR while maximally preserving the waveform's range and velocity resolution. Figure 5(c) illustrates that when using the traditional Riemann-SLM without considering the grouping structure, the core structure of "reference-data equal-weighted spread spectrum" in OFDM-DCSK is disrupted because it independently applies perturbations to each subcarrier, leading to severe deterioration of the ambiguity function sidelobes and a significant decrease in sensing performance. This comparative result strongly demonstrates the necessity and ingenuity of the grouping protection strategy adopted in this invention. It is not a simple application of existing PAPR suppression techniques, but rather an effective suppression of PAPR achieved while maintaining the integrity of the incoherent detection structure through an innovative grouping weighting design.

[0150] Please see Figure 6 , Figure 6 The performance of the proposed group selection mapping method in this invention, traditional OFDM-DCSK, and existing PAPR suppression techniques in terms of peak-to-average power ratio (PAPR) was compared. The figures clearly show that, under the same statistical probability conditions, the proposed G-SLM method can significantly reduce the PAPR of the signal. This effect stems from the group construction and mapping selection of candidate signal sequences without adding additional channel overhead or changing the original OFDM-DCSK modulation structure, thus effectively solving the problem of high PAPR affecting power amplifier efficiency and system stability in integrated sensing systems.

[0151] like Figure 7 As shown, Figure 7 The bit error rate (BER) performance of the OFDM-DCSK system before and after introducing the proposed G-SLM method was compared under different channel conditions. It can be seen that after adopting the G-SLM method proposed in this invention, the BER performance of the system remains essentially consistent with that of the traditional OFDM-DCSK system, with no significant performance degradation. This is because the G-SLM operation of this invention only affects the signal construction process at the transmitting end and does not affect the incoherent detection mechanism at the receiving end, thus ensuring communication reliability while reducing the peak-to-average power ratio (PAPR).

[0152] The simulation results above demonstrate that, while maintaining a narrow main lobe, low side lobes, and a relatively unchanged bit error rate curve, the waveform proposed in this scheme achieves a PAPR reduction of approximately 1.4 dB and 2.1 dB at the complementary cumulative distribution function (CCDF) of 10⁻³, compared to random phase SLM and Hadamard SLM, respectively. This significantly improves power amplifier efficiency and mitigates the dual impact of nonlinear distortion on communication and sensing performance. Overall, this invention provides a unified waveform design scheme that balances low PAPR, reliable incoherent communication, and high-resolution radar sensing.

[0153] The differential chaotic phase shift keying waveform design system provided in the embodiments of this application is described below. The differential chaotic phase shift keying waveform design system described below and the differential chaotic phase shift keying waveform design method described above can be referred to in correspondence.

[0154] Please see Figure 8 This invention also provides a differential chaotic phase-shift keying waveform design system suitable for integrated communication and sensing, the system comprising:

[0155] Modulation unit 301 is used to modulate the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; and to generate a corresponding chaotic reference sequence for each subcarrier group using a chaotic signal generator.

[0156] The frequency domain symbol sequence generation unit 302 is used to map the chaotic reference sequence onto the associated reference subcarrier, and multiply the chaotic reference sequence with the associated data symbols to map it onto the associated data subcarrier, thereby generating OFDM-DCSK frequency domain symbol sequences of multiple subcarriers;

[0157] The candidate subcarrier weight matrix construction unit 303 is used to construct a Riemann matrix based on a preset number of subcarrier groups, modulate the Riemann matrix element by element according to a preset number of candidate sequences to obtain a candidate weight matrix, and expand the candidate weight matrix according to a preset total number of subcarriers to obtain a candidate subcarrier weight matrix, so that the reference subcarriers and data subcarriers in the same subcarrier group under the same candidate sequence share the same complex weight.

[0158] The weighted frequency domain symbol sequence generation unit 304 is used to multiply the OFDM-DCSK frequency domain symbol sequence with each candidate sequence in the candidate subcarrier weight matrix symbol by symbol to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences.

[0159] The time-domain candidate waveform generation unit 305 is used to perform N-point IFFT processing on each weighted OFDM-DCSK frequency domain symbol sequence to obtain the corresponding OFDM-DCSK time-domain candidate waveform; where N is the preset total number of subcarriers;

[0160] Transmit waveform selection unit 306 is used to calculate the PAPR of each OFDM-DCSK time-domain candidate waveform and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

[0161] This invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0162] This invention also provides a computer-readable storage medium storing a computer program or instructions thereon, wherein the computer program or instructions, when executed by a processor, implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0163] This invention also provides a computer program product, including a computer program or instructions, which, when executed by a processor, implement the steps of the differential chaotic phase shift keying waveform design method as described above.

[0164] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0165] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion, such that a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or apparatus.

[0166] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0167] The units described as separate components may or may not be physically separate. The 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 the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0168] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0169] 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, in essence, or the part 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 to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0170] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A differential chaotic phase-shift keying waveform design method suitable for integrated communication and sensing, characterized in that, The method includes: Data modulation is performed on the bit stream to be transmitted according to the preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; a chaotic signal generator is used to generate a corresponding chaotic reference sequence for each subcarrier group; The chaotic reference sequence is mapped onto the associated reference subcarrier, and the chaotic reference sequence is multiplied with the associated data symbols to map onto the associated data subcarrier, generating OFDM-DCSK frequency domain symbol sequences of multiple subcarriers; A Riemann matrix is ​​constructed based on the preset number of subcarrier groups. The Riemann matrix is ​​then element-modulated according to the preset number of candidate sequences to obtain a candidate weight matrix. The candidate weight matrix is ​​then expanded according to the preset total number of subcarriers to obtain a candidate subcarrier weight matrix, so that the reference subcarriers and data subcarriers in the same subcarrier group under the same candidate sequence share the same complex weights. The OFDM-DCSK frequency domain symbol sequence is multiplied symbol by symbol with each candidate sequence in the candidate subcarrier weight matrix to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences; An N-point IFFT is performed on each of the weighted OFDM-DCSK frequency domain symbol sequences to obtain the corresponding OFDM-DCSK time domain candidate waveform; where N is the preset total number of subcarriers; Calculate the PAPR of each OFDM-DCSK time-domain candidate waveform, and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

2. The differential chaotic phase-shift keying waveform design method according to claim 1, characterized in that, A Riemann matrix is ​​constructed based on the preset number of subcarrier groups, and a candidate weight matrix is ​​obtained by element modulation of the Riemann matrix according to the preset number of candidate sequences. The step of expanding the candidate weight matrix according to the preset total number of subcarriers to obtain the candidate subcarrier weight matrix includes: Based on the preset number of subcarrier groups, construct a The Riemann matrix is ​​obtained by mapping each element of the Riemann matrix to a corresponding complex weight factor to obtain a complex matrix; where... The preset number of subcarrier groups; Row vectors are selected from the complex matrix according to a preset number of candidate sequences and their energy is normalized to form a candidate weight matrix; The candidate subcarrier weight matrix is ​​obtained by performing an extended product operation on the candidate weight matrix according to the preset total number of subcarriers.

3. The differential chaotic phase shift keying waveform design method according to claim 2, characterized in that, The elements in the Riemann matrix are represented as follows: In the formula: Let be the element in the i-th row and j-th column of the Riemann matrix; The complex weighting factors in the complex matrix are represented as follows: In the formula: Let be the complex weighting factor in the i-th row and j-th column of the complex matrix; The extended product operation of the candidate weight matrix is ​​represented as follows: In the formula: for The candidate subcarrier weight matrix, for Candidate weight matrix, It is a row vector of length L consisting entirely of 1s; This is for Kronecker product operations.

4. The differential chaotic phase shift keying waveform design method according to claim 1, characterized in that, The step of modulating the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups includes: The serial-to-parallel conversion of the bit stream to be transmitted is performed according to the preset number of subcarrier groups to obtain serial-to-parallel bit symbols of multiple subcarrier groups; Each of the serial-parallel bit symbols is subjected to BPSK modulation to obtain data symbols for multiple subcarriers.

5. A differential chaotic phase shift keying modulation and demodulation method suitable for integrated communication and sensing, characterized in that, The method involves a transmitter, a communication receiver, and a radar receiver; the method includes: The transmitter generates a transmission signal by performing a parallel-to-serial conversion on the transmission waveform generated by the differential chaotic phase shift keying waveform design method according to any one of claims 1-4; The received signal is obtained by receiving the transmitted signal through the wireless channel using the communication receiver; the received signal is then subjected to non-coherent detection processing to recover the corresponding bit data. The radar receiver receives the echo signal formed by the scattering of the transmitted signal; the echo signal is processed to obtain the distance and speed information of the transmitting target.

6. The differential chaotic phase shift keying modulation and demodulation method according to claim 5, characterized in that, The step of performing non-coherent detection processing on the received signal to recover the corresponding bit data includes: The received signal is sequentially subjected to serial-to-parallel conversion and N-point FFT processing to obtain the received frequency domain signals corresponding to the reference subcarriers and data subcarriers of multiple sets of subcarriers; The decision statistics for each group of subcarriers are obtained by performing conjugate correlation operations on the received frequency domain signals of the reference subcarrier and the data subcarrier in each group of subcarriers. The decision-maker performs decision processing based on the decision statistics to obtain the corresponding decision result; Perform parallel-to-serial conversion on all the aforementioned decision results to recover the bit data carried by each group of subcarriers.

7. A differential chaotic phase-shift keying waveform design system suitable for integrated communication and sensing, characterized in that, The system includes: The modulation unit is used to modulate the bit stream to be transmitted according to a preset number of subcarrier groups to obtain data symbols of multiple subcarrier groups; and a chaotic signal generator is used to generate a corresponding chaotic reference sequence for each subcarrier group. A frequency domain symbol sequence generation unit is used to map the chaotic reference sequence onto an associated reference subcarrier, and multiply the chaotic reference sequence with an associated data symbol to map it onto an associated data subcarrier, thereby generating OFDM-DCSK frequency domain symbol sequences for multiple subcarriers; The candidate subcarrier weight matrix construction unit is used to construct a Riemann matrix based on the preset number of subcarrier groups, perform element modulation on the Riemann matrix according to the preset number of candidate sequences to obtain a candidate weight matrix, and perform expansion processing on the candidate weight matrix according to the preset total number of subcarriers to obtain a candidate subcarrier weight matrix. The weighted frequency domain symbol sequence generation unit is used to multiply the OFDM-DCSK frequency domain symbol sequence with each candidate sequence in the candidate subcarrier weight matrix symbol by symbol to obtain a weighted OFDM-DCSK frequency domain symbol sequence of multiple candidate sequences; The time-domain candidate waveform generation unit is used to perform N-point IFFT processing on each of the weighted OFDM-DCSK frequency domain symbol sequences to obtain the corresponding OFDM-DCSK time-domain candidate waveform; where N is the preset total number of subcarriers; The transmit waveform selection unit is used to calculate the PAPR of each OFDM-DCSK time-domain candidate waveform and select the OFDM-DCSK time-domain candidate waveform associated with the smallest PAPR as the transmit waveform.

8. A computer device comprising a memory, a processor, and a computer program stored in the memory, characterized in that, The processor executes the computer program to implement the steps of the differential chaotic phase shift keying waveform design method as described in any one of claims 1-4.

9. A computer-readable storage medium having a computer program or instructions stored thereon, characterized in that, When the computer program or instructions are executed by the processor, they implement the steps of the differential chaotic phase shift keying waveform design method as described in any one of claims 1-4.

10. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by the processor, they implement the steps of the differential chaotic phase shift keying waveform design method as described in any one of claims 1-4.

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