Design method of synaesthesia integrated signal using scrambled complementary code orthogonal frequency division multiplexing

Abstract

The present invention proposes a scrambling complementary code orthogonal frequency division multiplexing communication and sensing integrated signal design method, including: constructing two orthogonal matrices A and D; the orthogonal matrix A and the orthogonal matrix D generate a scrambling complementary code matrix C on the m-th subcarrier m ; at the transmitting end, the serial bit stream is subjected to digital modulation and serial-to-parallel conversion to obtain M parallel data blocks; at the communication receiving end, the integrated signal is subjected to receiving end signal processing to obtain a communication bit stream; at the sensing receiving end, the integrated signal reaches the sensing receiving end after target reflection, and according to the echo signal r echo (t) the sensing received data containing delay and Doppler frequency shift information is obtained as R echo , according to the sensing received data as R echo the information matrix I containing only target information is obtained echo . The method can simultaneously realize the dual functions of communication and sensing. The adopted scrambling method can effectively improve the spectrum resource utilization rate of the integrated signal. The scrambling complementary code has ideal autocorrelation and cross-correlation characteristics, making the method have good sidelobe suppression ability.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communication, and in particular relates to a scrambling complementary code orthogonal frequency division multiplexing (Scrambling Complementary Codes-Orthogonal Frequency Division Multiplexing, SCC-OFDM) synaesthesia integrated signal design method. Background Art

[0002] In the 6G era, synaesthesia fusion will become a new technical challenge and an effective means to realize the perception, interconnection and intelligence of all things. The difficulty of synaesthesia fusion lies in how to design the integrated signal of communication and perception. There are two common integrated signal design methods: one is to detect radar targets based on communication signals, that is, directly use communication signals as integrated signals; the other is to modulate the communication information on its signal parameters (including waveform, beam and code type, etc.) on the basis of radar signals, so that it has both communication and perception functions. At present, in the use of communication waveforms to realize synaesthesia integration, OFDM signals are mainly used. This is because OFDM has the advantages of flexible subcarrier modulation, high spectrum efficiency, and easy synchronization and equalization. It has been widely used in actual communications. In addition, when OFDM signals are used as communication and perception shared signals, they also have advantages such as large time-bandwidth product, strong anti-fading and anti-interception capabilities, and high spectrum utilization. For this reason, scholars have widely studied OFDM communication and perception integrated processing related technologies in recent years.

[0003] At present, one type of OFDM communication perception is direct information modulation OFDM synaesthesia integrated shared signal. The autocorrelation function sidelobe of this integrated signal is relatively high, which is not conducive to target detection. Therefore, some scholars have proposed an orthogonal frequency division multiplexing (DS-OFDM) synaesthesia integrated signal based on direct sequence spread spectrum. By selecting a suitable pseudo-random code sequence to directly spread the communication data, the autocorrelation performance of the integrated signal is improved, thereby enhancing the target detection performance. The signal designed in this way has the advantages of low interception probability and strong anti-interference ability. However, the requirements for pseudo-random codes used in communication and radar systems are not the same. The radar system hopes that the autocorrelation function of the sequence must have a single peak, and the communication system hopes that the sequence maintains good cross-correlation to support multi-user communication. Therefore, in the integrated system, the pseudo-random sequence must have good autocorrelation and cross-correlation characteristics at the same time.

[0004] The Welch community clearly pointed out that a single code (m-sequence, Walsh sequence, Gold sequence, etc.) cannot have ideal periodic autocorrelation and cross-correlation performance at the same time. In addition, the multiplication of the pseudo-random code and the signal causes the spectrum of the integrated signal to expand, reducing the spectrum efficiency of the system.

[0005] Based on the above technical problems existing in the prior art, the present invention proposes a scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method. Summary of the invention

[0006] The invention provides a scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method.

[0007] The present invention adopts the following technical solutions:

[0008] A scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method, comprising:

[0009] Step 1: construct two orthogonal matrices A and D. The value of each element in the orthogonal matrix is ​​+1 or -1. The inner products between different rows and columns in the orthogonal matrix are all zero. The inner products of the same row and column are the dimensions of the corresponding matrix. The dimension of the orthogonal matrix A is N. s ×N s , each column scrambles a different OFDM symbol; the dimension of the orthogonal matrix D is M×M, and each column scrambles a different subcarrier;

[0010] Step 2: The orthogonal matrix A and the orthogonal matrix D generate the scrambling complementary code matrix C on the mth subcarrier. m , matrix C m It is expressed as:

[0011]

[0012] in, is the Kroc inner product, C m The dimension is Q×N s , Q is the number of code channels scrambled for each subcarrier, satisfying Q = N s ×M, the orthogonality of the orthogonal matrices A and D makes the scrambling complementary code matrix C on each subcarrier m (m=1,2,…,M) are also orthogonal;

[0013] Step 3: At the transmitting end, the serial bit stream is digitally modulated and converted into M parallel data blocks [b 1 , b 2 , …, b M ] T , scramble each parallel data block, b m (m=1,2,…,M) and the scrambling complementary code matrix C of the mth carrier m (m=1, 2, ..., M) for scrambling, performing OFDM modulation on the scrambled M-channel data to obtain an integrated signal, and transmitting it to the wireless channel via the antenna;

[0014] Step 4, at the communication receiving end, performing receiving end signal processing on the integrated signal to obtain a communication bit stream;

[0015] Step 5: At the sensing receiving end, the integrated signal reaches the sensing receiving end after being reflected by the target. echo (t) Obtain the sensing received data R containing the delay and Doppler frequency shift information echo , according to the perceived received data R echo Get the information matrix I containing only the target information echo .

[0016] Furthermore, step 3 includes:

[0017] Step 3.1: After the serial bit stream is modulated by BPSK digital modulation, a serial data block B is obtained. 1 , b 2 , …, b M ], each data block b m (m=1,2,…,M) contains N s symbols, namely

[0018] Step 3.2, after serial-to-parallel conversion, the serial data block B is converted into M parallel data blocks. The communication data after serial-to-parallel conversion is written in the form of a matrix:

[0019]

[0020] Step 3.3, scramble each parallel data block with the scrambling code on the corresponding carrier. The mth data block b m Scramble the complementary code matrix C on the mth subcarrier m , the scrambled complementary code on each subcarrier has Q subcodes, and the qth (q = 1, 2, ..., Q) subcode corresponds to C m The qth row of b m After the scrambling of the Q-path subcode, the data b on the mth (m=1, 2, ..., M) subcarrier m Respectively with C m The qth (q=1, 2, ..., Q) scrambling code is scrambled to obtain

[0021]

[0022] in, Represents a scrambling operation;

[0023] Step 3.4: encrypt the M-channel data Perform M-point IFFT transformation, serial-to-parallel conversion, and add a cyclic prefix CP to obtain an integrated signal after OFDM modulation;

[0024] In step 3.5, the integrated signal after OFDM modulation is subjected to digital-to-analog conversion and up-conversion in sequence, and then transmitted to the wireless channel through the antenna.

[0025] Furthermore, step 4 includes:

[0026] Step 4.1, the integrated signal reaches the communication receiving end after passing through the communication channel, and the communication receiving signal r(t) is expressed as:

[0027] r(t)=s(t)*h(t)+n c (t)......(4);

[0028] in, is the communication multipath channel model, δ(t) is the unit impulse function, L is the number of distinguishable paths, h l and τ l Represent the attenuation coefficient and delay of the lth path, n c (t) is the additive white Gaussian noise of the communication channel;

[0029] Step 4.2, r(t) is sent to the serial-to-parallel converter after down-conversion, A / D conversion, and removal of the cyclic prefix to obtain R = [R 1 , R 2 , …, R M ] T ;

[0030] Step 4.3: The parallel data block R is demodulated on each branch using FFT. The demodulated data block on the mth subcarrier is R′ m ;

[0031] Step 4.4: demodulate the data block R' on each subcarrier m (m=1,2,…,M) using different descrambling codebooks, R′ m After C m After descrambling, we get B′ m ;

[0032] Step 4.5, remove B' m The diagonal elements of Right now

[0033] Step 4.6, take out each of the M parallel data after descrambling After parallel-to-serial conversion, the communication data block is obtained Then, a serial bit stream is obtained through BPSK digital demodulation and decision feedback.

[0034] Furthermore, step 5 includes:

[0035] Step 5.1: The integrated signal reaches the sensing receiving end after being reflected by the target, and the echo signal is r echo (t);

[0036] Step 5.2, r echo (t) After down-conversion, A / D conversion, and removal of the cyclic prefix, it is sent to the perception signal processing module. After DFT processing, the scrambled data symbol matrix R containing delay and Doppler frequency shift information is obtained. echo :

[0037]

[0038] in, B is the communication symbol T The scrambled data matrix after scrambling, d and v are two vectors carrying delay and Doppler information respectively;

[0039] Step 5.3: The scrambled data symbol matrix R obtained by DFT processing at the sensing receiving end is echo and the scrambled data symbol matrix at the transmitter Perform matrix division to obtain the information matrix I containing only the target information echo ;

[0040] Step 5.4, for the information matrix I echo The mth row of the DFT process is performed to obtain the speed information of the perceived target;

[0041] Step 5.5, for the information matrix I echo The nth column of is processed by IDFT to obtain the distance information of the perceived target.

[0042] Furthermore, in step 5.1, assuming that the target is at a distance R and the radial velocity is v, then the echo signal r echo (t) is expressed as:

[0043]

[0044] Where ξ is the scattering coefficient of the target, f d =2vf c / c is the Doppler frequency shift introduced by the target speed, τ=2R / c is the relative delay introduced by the target distance, f c is the carrier frequency and c is the speed of light.

[0045] Furthermore, in step 5.2, The nth scrambled data symbol of the mth subcarrier It is expressed as:

[0046]

[0047] Furthermore, in step 5.4, the speed information of the perceived target is expressed as:

[0048]

[0049] when i=i 0 When V(i) reaches its maximum value, the sequence number i 0 And the target speed v satisfies the following formula:

[0050]

[0051] Furthermore, in step 5.5, the distance information of the perceived target is expressed as:

[0052]

[0053] When j = j 0 When D(j) reaches its maximum value, the sequence number j 0 The distance R from the target satisfies the following formula:

[0054]

[0055] Compared with the prior art, the present invention has the following advantages:

[0056] The scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method of the present invention adopts the scrambled complementary code and communication data scrambling method to carry information, and can simultaneously realize the dual functions of communication perception. Compared with the existing OFDM integrated signal based on spread spectrum, the scrambling method can effectively improve the spectrum resource utilization rate of the integrated signal. In addition, the scrambled complementary code has ideal autocorrelation and cross-correlation characteristics, so that the method has good sidelobe suppression capability. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 is a schematic diagram of generating a scrambling complementary code in an embodiment of the present invention;

[0058] Figure 2 Schematic diagram of the principle of signal processing at the transmitting end in an embodiment of the present invention;

[0059] Figure 3 is a schematic diagram of the principle of signal processing at the receiving end in an embodiment of the present invention;

[0060] Figure 4 This is a comparison chart of the distance ambiguity function and the speed ambiguity function. DETAILED DESCRIPTION

[0061] In order to more clearly understand the above-mentioned objects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0062] Example

[0063] The scrambling complementary code orthogonal frequency division multiplexing (SCC-OFDM) synaesthesia integrated signal design method comprises: scrambling complementary code design, communication transmitting end signal processing, communication receiving end signal processing and perception receiving end signal processing;

[0064] The scrambling complementary code design includes:

[0065] Step A1: Figure 1 As shown, construct two orthogonal matrices A and D. The value of each element in the matrix is ​​+1 or -1, and the inner products between different rows and columns in the matrix are all zero. The inner products of the same row and column are the dimensions of the corresponding matrix. The dimension of matrix A is N s ×N s , each column scrambles different OFDM symbols; the dimension of matrix D is M×M, each column scrambles different subcarriers, A and D are expressed as:

[0066]

[0067]

[0068] where a i，j and d i，j are the i-th row and j-th column elements of matrices A and D respectively;

[0069] Step A2: Scrambling complementary code matrix C on the mth subcarrier m Can be generated from matrices A and D, matrix C m It can be expressed as:

[0070]

[0071] In the formula is the Crocker inner product. From the above formula, we can see that C m The dimension is Q×N s , Q is the number of code channels scrambled for each subcarrier, and Q = N s ×M, due to the orthogonality of matrices A and D, the scrambling complementary code matrix C on each subcarrier m(m=1,2,…,M) are also orthogonal, where the codebook of the qth (q=1,2,…,Q) code channel is According to the codebook construction principle, c m，q，n (n=1,2,…,N s ) corresponds to the i-th (i=1, 2, ...M)-th row and m-th column element of matrix D and the j-th (j=1, 2, ...N s ) row and column n, that is, the nth code element of the scrambling code on the qth code channel corresponding to the mth subcarrier can be expressed as c m，q，n =d i，m a j，n ; For example, when the first code channel q=1, i=1, j=1, c m，1，n =d 1，m a 1，n ; When the second code channel q=2, i=1,j=2,c m，2，n =d 1，m a 2，n ; Nth s Code channels q = N s When i=1, j=N s , Nth s +1 code channel q=N s +1, i=2, j=1, Qth code channel q=N s When M, i=M, j=N s ,

[0072] It should be noted that, in step A1, the orthogonality between different columns in the A matrix can separate different symbols; and the orthogonality between different columns in the D matrix can eliminate interference between different carriers.

[0073] The communication transmitting end signal processing comprises:

[0074] Step B1: Figure 2 As shown, at the transmitting end, the serial bit stream is first digitally modulated by BPSK (Binary Phase ShiftKeying) to obtain a serial data block B = [b 1 , b 2 , …, b M ], each data block b m (m=1,2,…,M) contains N s symbols, namely

[0075] Step B2: After serial-to-parallel conversion, the serial data block B obtains M parallel data blocks. For a more intuitive description, the communication data after serial-to-parallel conversion is written in the form of a matrix:

[0076]

[0077] Step B3: Each parallel data block is scrambled with the scrambling code on the corresponding carrier. The mth data block b m Scramble the complementary code matrix C on the mth subcarrier m , the scrambling complementary code on each subcarrier has Q scrambling codes, and the qth (q = 1, 2, ..., Q) scrambling code corresponds to C m The qth row of b m After being scrambled by the Q-path scrambling code, the data b on the mth (m=1, 2, ..., M) subcarrier m Respectively with C m The qth (q=1, 2, ..., Q) scrambling code is scrambled to obtain

[0078]

[0079] in, Represents a scrambling operation;

[0080] Step B4: The scrambled M-channel data Perform M-point IFFT transformation, serial-to-parallel conversion, and then add a cyclic prefix (CP);

[0081] Step B5: The integrated signal after OFDM modulation is subjected to digital-to-analog conversion and up-conversion in sequence, and then transmitted to the wireless channel through the antenna. The baseband complex envelope of the transmitted integrated signal is expressed as:

[0082]

[0083] Among them, M represents the number of subcarriers, Q represents the number of code channels contained in each subcarrier, and N s represents the number of OFDM symbols contained in a pulse, c(m, q, n) is the nth code element of the scrambling code on the mth subcarrier and the qth code channel. From step A2, we know that c(m, q, n) = d i，m a j，n (q=1,…,Q,i=1,…,M,j=1,…,N s ), b(m, n) is the nth communication data modulated on the mth subcarrier, T b is the symbol width of an OFDM symbol, which consists of a cyclic prefix and a valid OFDM symbol, that is, T b =T G +T,T G is the cyclic prefix length, T is the effective symbol length, represents the carrier frequency of the mth subcarrier, Δf is the carrier spacing, and in order to satisfy the orthogonality between carriers, Δf = 1 / T, rect(t / T b ) is the unit rectangular window function, expressed as:

[0084]

[0085] The integrated transmission signal s(t) is transmitted from the antenna to the wireless communication channel (multipath fading channel) after up-conversion, and then reaches the communication receiving end. After being reflected by the target, it reaches the sensing receiving end. Since the signals received by sensing and the signals received by communication must undergo down-conversion, A / D conversion, CP removal and other operations, the same receiver block diagram is used to illustrate the processing flow of the receiving end signal, such as Figure 3 As shown, the communication receiving end signal is r(t), and the perception receiving end signal is r echo (t), the communication receiving end signal processing includes:

[0086] Step C1.1: The integrated signal reaches the communication receiving end after passing through the communication channel. The received signal r(t) can be expressed as:

[0087] r(t)=s(t)*h(t)+n c (t);

[0088] in, is the communication multipath channel model, δ(t) is the unit impulse function, L is the number of resolvable paths, h l and τ l Represent the attenuation coefficient and delay of the lth path, n c (t) is the additive white Gaussian noise of the communication channel;

[0089] Step C1.2: r(t) is down-converted, A / D converted, and the cyclic prefix is ​​removed before being fed into a serial-to-parallel converter to obtain R = [R 1 , R 2 , …, R M ] T ;

[0090] Step C1.3: The parallel data block R uses FFT to demodulate each branch, and the demodulated data of the mth subcarrier is:

[0091]

[0092] Step C1.4: Demodulate the data block R' on each subcarrier m (m = 1, 2, ..., M) using different descrambling codebooks, i.e., demodulation data block R' on the mth subcarrier m After C m After descrambling, we get B′ m, expressed as:

[0093]

[0094] Step C1.5: Remove B′ m The diagonal elements of (m=1, 2, ..., M) are denoted as Right now

[0095] Step C1.6: M parallel data blocks After parallel-to-serial conversion, the communication data block is obtained Then, a serial bit stream is obtained through BPSK digital demodulation and decision feedback.

[0096] The sensing receiving end signal processing comprises:

[0097] Step C2.1: The integrated signal reaches the sensing receiving end after being reflected by the target. The echo signal received by the sensing receiving end is r echo (t), assuming the target is at a distance R and the radial velocity is v, then the echo signal r echo (t) is expressed as:

[0098]

[0099] Where ξ is the scattering coefficient of the target, f d =2vf c / c is the Doppler frequency shift introduced by the target speed, τ=2R / c is the relative delay introduced by the target distance, f c is the carrier frequency, c is the speed of light;

[0100] Step C2.2: echo (t) After down-conversion, A / D conversion, and removal of the cyclic prefix, it is sent to the perception signal processing module, where DFT processing is first performed to obtain the perception reception data containing delay and Doppler frequency shift information, which is R echo :

[0101]

[0102] in, B is the communication symbol T The scrambled data symbol matrix after scrambling, The nth scrambled data symbol of the mth subcarrier It can be expressed as:

[0103]

[0104] d and v are two vectors carrying delay and Doppler information, respectively. For a fixed symbol, the delay introduces different phase shifts between different carriers, and the phase shift difference between two adjacent carriers is X. For a fixed carrier, the Doppler frequency shift introduces different phase shifts between different symbols, and the phase shift difference between two adjacent symbols is represented by Y. Then X and Y are expressed as follows:

[0105]

[0106] Then d and v are expressed as:

[0107]

[0108] Step C2.3: The scrambled data symbol matrix R obtained by DFT processing at the sensing receiving end echo and the scrambled data symbol matrix at the transmitter Perform matrix division to eliminate the influence of scrambled data symbols on target detection, thereby obtaining an information matrix I containing only target information echo ;

[0109]

[0110] Step C2.4: For matrix I echo Perform N-point DFT processing on the mth row to obtain the speed information of the perceived target;

[0111]

[0112] Among them, I echo (m,:) represents the information matrix I of the target information echo The mth row element, I echo (m, n) is the element in the mth row and nth column. From the above formula, we can see that when i=i 0 When V(i) reaches its maximum value, the sequence number i 0 And the target speed v satisfies the following formula:

[0113]

[0114] in Represents floor operation;

[0115] Step C2.5: For matrix I echo Perform M-point IDFT processing on the nth column to obtain the distance information of the perceived target;

[0116]

[0117] Among them, I echo (:, n) represents the information matrix I of the target information echo The nth column element, I echo(m, n) is the element in the mth row and nth column. From the above formula, we can see that when j=j 0 When D(j) reaches its maximum value, the sequence number j 0 The distance R from the target satisfies the following formula:

[0118]

[0119] in Represents the floor operation.

[0120] In order to verify the superiority of the SCC-OFDM integrated signal in this embodiment, this embodiment simulates and analyzes the ambiguity function of the integrated signal. By comparing the ambiguity functions of the direct sequence spread spectrum OFDM (DS-OFDM) integrated signal and the scrambled complementary code OFDM (SCC-OFDM) integrated signal, the superiority of the method described in this embodiment is proved. In the simulation, it is assumed that the time T of an OFDM symbol is b is 2μs, the carrier spacing Δf is 0.5MHz, the number of subcarriers M is 8, and the number of symbols in a pulse is N s is 8, the carrier frequency f c The frequency band is 5 GHz, and the m-sequences with feedback coefficients of (1 0 0 1 0 1) and (1 1 0 1 1 1) are selected to generate a family of Gold sequences. The ambiguity functions of the gold spread spectrum OFDM integrated signal and the SCC-OFDM integrated signal are simulated respectively. Figure 4 It can be seen that the side lobe of the ambiguity function diagram of the SCC-OFDM integrated signal is smaller. The distance ambiguity function and speed ambiguity function of the two are almost the same. The main side lobe ratio of the distance dimension of the DS-OFDM integrated signal is:

[0121] 20lg(1 / 0.0596)≈24.50dB;

[0122] The range-dimensional main-sidelobe ratio of the SCC-OFDM integrated signal is:

[0123] 20lg(1 / 0.0085)≈41.41dB;

[0124] It can be clearly seen that the range sidelobe of the SCC-OFDM integrated signal is significantly reduced compared to that of DS-OFDM. This is due to the ideal correlation of the scrambling code. At the same time, assuming that each OFDM symbol period is T b , then the data rate is 1 / T b , assuming that the spreading sequence period is N, the bandwidth of each subcarrier is N / T b , the number of subcarriers is M, then the spectrum efficiency of the DS-OFDM integrated signal is: (1 / T b )÷(M·N / Tb )=1 / (MN)bit / s / Hz, and the spectrum efficiency of the SCC-OFDM integrated signal is: (1 / T b )÷(M·1 / T b )=1 / M bit / s / Hz, therefore, the SCC-OFDM system has higher spectrum utilization than the DS-OFDM system.

[0125] The present invention is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, which are within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method, characterized in that: include: Step 1: construct two orthogonal matrices A and D. The value of each element in the orthogonal matrix is ​​+1 or -1. The inner products between different rows and columns in the orthogonal matrix are all zero. The inner products of the same row and column are the dimensions of the corresponding matrix. The dimension of the orthogonal matrix A is N. s ×N s , each column scrambles a different OFDM symbol; the dimension of the orthogonal matrix D is M×M, and each column scrambles a different subcarrier; Step 2: The orthogonal matrix A and the orthogonal matrix D generate the scrambling complementary code matrix C on the mth subcarrier. m , matrix C m It is expressed as: in, is the Kroc inner product, C m The dimension is Q×N s , Q is the number of code channels scrambled for each subcarrier, satisfying Q = N s ×M, the orthogonality of the orthogonal matrices A and D makes the scrambling complementary code matrix C on each subcarrier m (m=1, 2, ..., M) are also orthogonal; Step 3: At the transmitting end, the serial bit stream is digitally modulated and converted into M parallel data blocks [b1, b2, ..., b M ] T , scramble each parallel data block, b m (m=1, 2, ..., M) and the scrambling complementary code matrix C of the mth carrier m (m=1, 2, ..., M) for scrambling, performing OFDM modulation on the scrambled M-channel data to obtain an integrated signal, and transmitting it to the wireless channel via the antenna; Step 4, at the communication receiving end, performing receiving end signal processing on the integrated signal to obtain a communication bit stream; Step 5: At the sensing receiving end, the integrated signal reaches the sensing receiving end after being reflected by the target. echo (t) The received data containing the delay and Doppler frequency shift information is obtained as R echo , according to the perceived received data R echo Get the information matrix I containing only the target information echo ,include: Step 5.1: The integrated signal reaches the sensing receiving end after being reflected by the target, and the echo signal is r echo (t), assuming the target is at a distance R and the radial velocity is v, then the echo signal r echo (t) is expressed as: Where ξ is the scattering coefficient of the target, f d =2vf c / c is the Doppler frequency shift introduced by the target speed, τ=2R / c is the relative delay introduced by the target distance, f c is the carrier frequency, c is the speed of light, f m is the subcarrier frequency based on OFDM division; rect(·) is the unit rectangular window function; T b is the code element width of an OFDM symbol; Step 5.2, r echo (t) After down-conversion, A / D conversion, and removal of the cyclic prefix, it is sent to the perception signal processing module. After DFT processing, the scrambled data symbol matrix R containing delay and Doppler frequency shift information is obtained. echo : in, B is the communication symbol T The scrambled data matrix after scrambling, d and v are two vectors carrying delay and Doppler information respectively, The nth scrambled data symbol of the mth subcarrier It is expressed as: Step 5.3: The scrambled data symbol matrix R obtained by DFT processing at the sensing receiving end is echo and the scrambled data symbol matrix at the transmitter Perform matrix division to obtain the information matrix I containing only the target information echo ; Step 5.4, for matrix I echo The mth row of the DFT process is performed to obtain the speed information of the perceived target. The speed information of the perceived target is expressed as: When i=i0, V(i) reaches its maximum value, and the sequence number i0 and the target speed v satisfy the following formula: Step 5.5, for matrix I echo The nth column of is processed by IDFT to obtain the distance information of the perceived target.

2. The scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method according to claim 1, characterized in that: Step 3 includes: Step 3.1: After the serial bit stream is modulated by BPSK digital modulation, a serial data block B = [b1, b2, ..., b M ], each data block b m (m=1,2,…,M) contains N s symbols, namely Step 3.2, after serial-to-parallel conversion, the serial data block B is converted into M parallel data blocks. The communication data after serial-to-parallel conversion is written in the form of a matrix: Step 3.3, scramble each parallel data block with the scrambling code on the corresponding carrier. The mth data block b m Scramble the complementary code matrix C on the mth subcarrier m , the scrambled complementary code on each subcarrier has Q subcodes, and the qth (q=1,2,…,Q) subcode corresponds to C m The qth row of b m After the scrambling of the Q-path subcode, the data b on the mth (m=1, 2, ..., M) subcarrier m Respectively with c m The qth (q=1,2,…,Q)th scrambling code is scrambled to obtain in, Represents a scrambling operation; Step 3.4: encrypt the M-channel data Perform M-point IFFT transformation, serial-to-parallel conversion, and add a cyclic prefix CP to obtain an integrated signal after OFDM modulation; In step 3.5, the integrated signal after OFDM modulation is subjected to digital-to-analog conversion and up-conversion in sequence, and then transmitted to the wireless channel through the antenna.

3. The scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method according to claim 2, characterized in that: Step 4 includes: Step 4.1, the integrated signal reaches the communication receiving end after passing through the communication channel, and the communication receiving signal r(t) is expressed as: r(t)=s(t)*h(t)+n c (t)……(4); in, is the communication multipath channel model, δ(t) is the unit impulse function, L is the number of distinguishable paths, h l and τ l Represent the attenuation coefficient and delay of the lth path, n c (t) is the additive white Gaussian noise of the communication channel; Step 4.2, r(t) is sent to the serial-to-parallel converter after down-conversion, A / D conversion, and removal of the cyclic prefix to obtain R = [R1, R2, ..., R M ] T ; Step 4.3: The parallel data block R is demodulated on each branch using FFT. The demodulated data block on the mth subcarrier is R′ m ; Step 4.4: demodulate the data block R' on each subcarrier m (m=1,2,…,M) using different descrambling codebooks, R′ m After C m After descrambling, we get B′ m ; Step 4.5, remove B' m The diagonal elements of Right now Step 4.6, take out each of the M parallel data after descrambling After parallel-to-serial conversion, the communication data block is obtained Then, a serial bit stream is obtained through BPSK digital demodulation and decision feedback.

4. The scrambled complementary code orthogonal frequency division multiplexing synaesthesia integrated signal design method according to claim 1, characterized in that: In step 5.5, the distance information of the perceived target is expressed as: Where R is the distance between the receiver and the target, m is the variable defined by the subscript in the summation symbol; T b is the code element width of an OFDM symbol; Δf is the carrier spacing based on OFDM division; When j=j0, D(j) reaches its maximum value, and the sequence number j0 and the target distance R satisfy the following formula:

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