Cyclic prefix clipping enhanced optical communication perception integration method and system

Abstract

The embodiment of the application provides a kind of based on cyclic prefix shear enhancement integrated method and system of optical communication perception, it is related to communication and signal processing field, the method includes: in sending part, by to initial signal sequence is carried out shear enhancement processing, add cyclic prefix, obtain cyclic prefix enhanced signal and are converted into optical signal and are sent to receiving device.In receiving part, the signal sequence to be handled obtained is carried out inverse shear enhancement processing, correlation operation, determine the estimated value of symbol offset, then after removing cyclic prefix, information recovery processing obtains communication information;According to the estimated value of symbol offset determines time delay, and then realizes optical perception ranging speed measurement.The mode of shear enhancement and adding cyclic prefix, can effectively eliminate intersymbol interference and clipping distortion, reduce bit error rate, also can realize passive time difference estimation perception, without additional pilot or perception signal, it realizes the fusion of communication and perception function, saves spectrum resource.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication and signal processing, in particular to an optical communication and sensing integrated method and system based on cyclic prefix clipping enhancement. BACKGROUND

[0002] With the rapid development of emerging applications such as intelligent manufacturing, autonomous driving, and Internet of Things, higher requirements are put forward for wireless transmission systems with high speed, low delay, and strong sensing. The performance of traditional wireless communication systems such as radio frequency communication is difficult to meet the above application requirements in complex environments with limited bandwidth resources and serious electromagnetic interference.

[0003] Compared with the above, wireless optical communication has become an important complementary means for short-distance high-speed data communication due to its advantages of abundant bandwidth, high transmission rate, and strong anti-electromagnetic interference capability. At the same time, optical sensing technology using the reflection and propagation characteristics of optical signals for target distance and speed sensing has gradually emerged, and has broad application prospects in indoor positioning, intelligent driving assistance, and other scenarios.

[0004] However, most of the current wireless optical communication systems and optical sensing systems are still independently deployed, resulting in device duplication, increased cost, waste of spectrum resources, and difficulty in flexible deployment in environments with limited spatial resources. At the same time, as a high spectral efficiency modulation technology, orthogonal frequency division multiplexing (OFDM) is widely used in wireless optical communication, but its signal has a high peak-to-average power ratio problem, which easily causes clipping distortion in actual light sources, and there are problems such as channel interference suppression, which affect communication performance and sensing accuracy. SUMMARY

[0005] The present application provides an optical communication and sensing integrated method and system based on cyclic prefix clipping enhancement to solve the problems of clipping distortion in optical communication, waste of spectrum resources caused by independent optical communication and sensing, and low optical communication and sensing accuracy.

[0006] To solve the above problems, the present application is implemented as follows:

[0007] In a first aspect, the present application provides an optical communication and sensing integrated method based on cyclic prefix clipping enhancement, which comprises a sending part and a receiving part, and the sending part comprises:

[0008] Step 11, generating at least one initial signal sequence with a length of N carrying communication information, N being a positive integer;

[0009] Step 12, judging whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, when there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, performing a shear enhancement processing on the initial signal sequence through the following formula to obtain an enhanced signal sequence with a length of , and dividing the enhanced signal sequence into L block sequences, the length of the block sequence is N, and L is an integer not less than 3:

[0010] ,

[0011] , wherein, sm(m) represents a signal value of the mth point in the mth enhanced signal sequence, ; , wherein, sm(m) represents a signal value of the mth point in the mth initial signal sequence, when m takes 0~N-1, is an actual signal value, when m takes takes a value of 0; is a preset peak value, used for performing a shear processing on the initial signal sequence; , wherein, sm(m) represents a signal value of the mth point in the mth initial signal sequence, when m takes 0~N-1,

[0012] ;

[0013] Step 13, taking a signal with a length of behind each block sequence as a cyclic prefix, and copying and adding the cyclic prefix to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, is a preset cyclic prefix length; the length of the block sequence added with the cyclic prefix is , ; the length of the cyclic prefix enhanced signal is ;

[0014] Step 14, generating an optical signal based on the cyclic prefix enhanced signal and sending the optical signal to a receiving device;

[0015] The receiving part comprises:

[0016] Step 21, receiving the optical signal from the sending device, and converting the optical signal to obtain a to-be-processed signal sequence;

[0017] Step 22, performing an inverse shear enhancement processing on the to-be-processed signal sequence to obtain a reconstructed signal sequence;

[0018] ​​​​​​​​Step 23, performing correlation operation on the reconstructed signal sequence to determine an estimation of the symbol offset, and then obtaining an initial recovered signal sequence; wherein the initial recovered signal sequence has a length of ;

[0019] Step 24, removing the cyclic prefix in the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence;

[0020] Step 25, performing information recovery processing on the target recovered signal to obtain communication information;

[0021] Step 26, determining a time delay according to the estimation of the symbol offset;

[0022] Step 27, determining the distance and relative speed between the sending device and the receiving device according to the time delay.

[0023] Optionally, the step 11 comprises:

[0024] generating target bit stream information, and mapping the target bit stream information into a complex symbol sequence according to a preset modulation mode; wherein the target bit stream information carries communication information;

[0025] performing inverse fast Fourier transform on the complex symbol sequence to obtain parallel time domain signals;

[0026] performing parallel-serial conversion on the parallel time domain signals to obtain a serial time domain signal sequence;

[0027] performing power control on the serial time domain signal sequence to obtain an initial signal sequence.

[0028] Optionally, the length of the cyclic prefix is greater than the maximum time delay spread of a channel.

[0029] Optionally, the step 21 comprises:

[0030] receiving the optical signal sent by the sending device, and converting the optical signal into an electrical signal;

[0031] inputting the electrical signal into an analog-digital converter to obtain an initial signal sequence to be processed;

[0032] inputting the initial signal sequence to be processed into a digital signal processor to perform modeling processing, and obtaining a modeled signal sequence;

[0033] performing segmentation processing on the modeled signal sequence according to a length to obtain a signal sequence to be processed, and then performing segmentation on the signal sequence to be processed according to a length to obtain a segmented signal sequence to be processed.

[0034] Optionally, the reconstructed signal sequence is represented by the following formula:

[0035] ,

[0036] wherein, represents a symbol offset, represents a signal value of the pth point in the mth reconstructed signal sequence when the symbol offset is represents the mth to-be-processed sample sequence, represents a rounding function, represents a remainder of a divided by b, represents a sign function.

[0037] Optionally, the step 23 comprises:

[0038] An estimated value of the symbol offset is determined by performing a correlation operation on the reconstructed signal sequence according to the following formula:

[0039] ,

[0040] wherein, represents a signal value of the ith point in the mth reconstructed signal sequence when the symbol offset is is an estimated value of the symbol offset, is a length of a sliding window, is a maximum value point function.

[0041] An initial recovered signal sequence is determined according to the estimated value of the symbol offset.

[0042] Optionally, the length of the sliding window is .

[0043] Optionally, the step 25 comprises:

[0044] The initial recovered signal sequence is converted into a parallel initial recovered signal.

[0045] A fast Fourier transform is performed on the parallel initial recovered signal to obtain an initial recovered signal in a frequency domain.

[0046] A first-order equalizer is used to process the initial recovered signal in the frequency domain to obtain an equalized initial recovered signal.

[0047] The equalized initial recovered signal is demodulated according to a preset demodulation mode to obtain the communication information.

[0048] ​​Optionally, the sending part further comprises: when there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and the signal value of each point in the initial signal sequence is not less than zero, L is equal to 1.

[0049] When there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and there is a point with a signal value less than zero in the initial signal sequence, L is equal to 2.

[0050] In a second aspect, the present application provides a cyclic prefix-based shear enhancement integrated optical communication and perception system, which comprises a sending device and a receiving device, and the sending device comprises:

[0051] a signal generation module for generating at least one initial signal sequence with a length of N carrying communication information, N being a positive integer;

[0052] a shear enhancement module for judging whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, and when there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, performing shear enhancement processing on the initial signal sequence through the following formula to obtain an enhanced signal sequence with a length of and dividing the enhanced signal sequence into L block sequences, the length of the block sequence being N, and L being an integer not less than 3:

[0053] ,

[0054] wherein, represents the signal value of the mth point in the mth enhanced signal sequence, the value of ; ; represents the signal value of the mth point in the mth initial signal sequence, when takes 0~ N-1, is the actual signal value, when takes , the value of is 0; is a preset peak value for clipping processing on the initial signal sequence; represents the following formula:

[0055] ;

[0056] a cyclic prefix adding module for adding a signal with a length of at the rear of each block sequence as a cyclic prefix, and copying and adding the cyclic prefix to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, ​is a preset cyclic prefix length; the length of the block sequence added with the cyclic prefix is , = ; the length of the cyclic prefix enhanced signal is ;

[0057] The signal conversion and sending module is configured to generate an optical signal based on the cyclic prefix enhanced signal and send the optical signal to a receiving device.

[0058] The receiving device comprises:

[0059] The signal receiving and conversion module is configured to receive the optical signal from the sending device and convert the optical signal to obtain a to-be-processed signal sequence.

[0060] The signal reconstruction module is configured to perform inverse shear enhancement processing on the to-be-processed signal sequence to obtain a reconstructed signal sequence.

[0061] The correlation calculation module is configured to perform correlation operation on the reconstructed signal sequence to determine an estimated value of a symbol offset, and further obtain an initial recovered signal sequence; the length of the initial recovered signal sequence is .

[0062] The cyclic prefix removal module is configured to remove the cyclic prefix in the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence.

[0063] The information recovery module is configured to perform information recovery processing on the target recovered signal to obtain communication information.

[0064] The time delay determination module is configured to determine a time delay according to the estimated value of the symbol offset.

[0065] The ranging and speed measurement module is configured to determine a distance and a relative speed between the sending device and the receiving device according to the time delay.

[0066] The embodiment of the application provides an optical communication and perception integrated method based on cyclic prefix shear enhancement, which has the following advantages:

[0067] The embodiment of the present application provides a kind of based on cyclic prefix shear enhancement integrated method of optical communication perception, in sending part, by being respectively carried out to the initial signal sequence of the communication information of acquisition to add cyclic prefix, shear enhancement processing is obtained, then the cyclic prefix enhanced signal is converted into optical signal and sent to receiving device.In receiving part, after the signal sequence to be processed of receiving conversion is carried out inverse shear enhancement processing and the reconstructed signal sequence is obtained, the correlation operation is carried out based on cyclic prefix to the reconstructed signal sequence, the estimated value of symbol offset is determined, and then the initial recovery signal sequence is obtained, after removing cyclic prefix, information recovery processing can obtain communication information, realize communication function;At the same time, according to the estimated value of symbol offset, the time delay of optical communication can be further determined, and then the distance and relative speed between sending device and receiving device are determined according to the time delay, to realize optical perception ranging and speed measurement.

[0068] In the above manner, by adding cyclic prefix, not only the inter-symbol interference caused by channel multipath effect can be effectively eliminated, but also the passive time difference estimation (TDOA, Time Difference of Arrival) perception can be realized by using the autocorrelation characteristics, without additional pilot or perception signal, so that the deep integration of communication and perception function is realized, the system complexity is reduced, and the spectrum resource is saved.Meanwhile, by using shear enhancement processing, not only the communication information is effectively retained, but also the clipping distortion caused by peak power limitation is suppressed, the bit error rate is reduced, and the accuracy of calculating symbol offset according to cyclic prefix is improved, so that the influence of time delay on signal recovery is reduced, the accuracy of optical perception ranging and speed measurement is improved, and the synchronous enhancement of optical communication and optical perception effect is realized. BRIEF DESCRIPTION OF DRAWINGS

[0069] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings, in which:

[0070] Figure 1 The step flow chart of the embodiment of the present application is provided for a kind of based on cyclic prefix shear enhancement integrated method of optical communication perception;

[0071] Figure 2 The step flow chart of the embodiment of the present application is provided for another kind of based on cyclic prefix shear enhancement integrated method of optical communication perception;

[0072] Figure 3 The flow chart of the embodiment of the present application is provided for a kind of inverse shear enhancement processing;

[0073] Figure 4 The structure block diagram of the embodiment of the present application is provided for a kind of based on cyclic prefix shear enhancement integrated system of optical communication perception;

[0074] Figure 5 A comparison chart of simulation results of three different systems in terms of communication awareness under specific conditions provided for embodiments of the present application;

[0075] Figure 6 A chart of joint distance and velocity estimation results of a single target obtained by the optical communication and awareness integrated system provided for embodiments of the present application under a simulation scenario;

[0076] Figure 7 A distribution chart of distance estimation results of a single target obtained by the optical communication and awareness integrated system provided for embodiments of the present application under a simulation scenario;

[0077] Figure 8 A distribution chart of velocity estimation results of a single target obtained by the optical communication and awareness integrated system provided for embodiments of the present application under a simulation scenario. DETAILED DESCRIPTION

[0078] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by reference to the accompanying drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application.

[0079] Reference Figure 1 A step flowchart of an embodiment of a method of optical communication and awareness integration based on cyclic prefix clipping enhancement is given, and the method comprises a sending part and a receiving part.

[0080] The sending part comprises:

[0081] Step 11, generating at least one initial signal sequence with a length of N carrying communication information, N being a positive integer.

[0082] The initial signal sequence is a time domain signal sequence obtained based on orthogonal frequency-division multiplexing (OFDM) modulation. A time domain signal sequence obtained based on OFDM modulation can also be referred to as an OFDM block or an OFDM symbol, which is not limited in the present application.

[0083] Step 12, judging whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence. When there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, clipping enhancement processing is performed on the initial signal sequence by the following formula to obtain an enhanced signal sequence with a length of The enhanced signal sequence is equally divided into L block sequences, the length of the block sequence being N, and L being an integer not less than 3:

[0084]

[0085] wherein one initial signal sequence with a length of N corresponds to one enhanced signal sequence with a length of .

[0086] In formula (1), sm(n) represents a signal value of the mth point in the mth enhanced signal sequence, and n represents a point number of the mth enhanced signal sequence. sm(n) represents a signal value of the mth point in the mth initial signal sequence, and n represents a point number of the mth initial signal sequence.

[0087] Correspondingly, for sm(n), when n takes N-1, i.e. n takes 0~N-1, sm(n) is an actual signal value, and when n takes other values, sm(n) takes 0; for sm(n), when n takes N-1, i.e. n takes 0~N-1, sm(n) is an actual signal value, and when n takes other values, sm(n) takes 0.

[0088] is a preset peak value, is greater than 0, and is determined according to inherent characteristics of a sending device, and is used for clipping processing of the initial signal sequence. represents a clipping function, and can be expressed as the following formula:

[0089] 。(2)

[0090] A signal value can be positive, negative or 0, and a signal amplitude refers to an absolute value of a signal value. represents an absolute value, and is used for representing a signal amplitude.

[0091] ​​​​​​​​​​​​​​​​​​​​​​It is understood that during optical communication, the time signal sequence used to convert into an optical signal must be non-negative. Furthermore, due to the inherent characteristics of optical signal transmission devices, the peak power of the light source is limited. Therefore, if the amplitude of the initial signal sequence is too high, clipping distortion can easily occur during communication. To address this issue, the present invention employs clipping enhancement, which uses an additional sequence to transmit the positive and negative value information and trimming information of the initial signal sequence. This effectively suppresses clipping distortion while preserving the information recorded in the signal sequence, thereby improving communication reliability.

[0092] When there is a signal with an amplitude exceeding the preset peak value in the initial signal sequence, formula (1) gives the specific process of shear enhancement:

[0093] Corresponding to the first and second expressions on the right side of formula (1), the positive value portion of the initial signal sequence remains unchanged and is still recorded in the initial signal sequence, that is, the first block sequence; the negative value portion of the initial signal sequence is reversed to a positive value and recorded in the second block sequence of length N. Therefore, the second block sequence is used to record the negative signal points in the initial signal sequence. For example, the initial signal sequence is [-2, 1, -6, 0, 5]. After only the negative value portion is reversed, the corresponding sequences obtained are [0, 1, 0, 0, 5] and [2, 0, 6, 0, 0]. The positions of -2 and -6 in the initial signal sequence are 0th and 2nd, respectively. Correspondingly, the reversed values ​​2 and 6 are also 0th and 2nd in the second block sequence. At the same time, the signal values ​​of the 0th and 2nd positions in the first block sequence are recorded as 0. Of course, when the signal values ​​of the points in the initial signal sequence are not less than 0, the signal values ​​of each point in the second block sequence can be recorded as 0.

[0094] Corresponding to the third expression on the right side of formula (1), the initial signal sequence is clipped and the clipping information is recorded in the third signal sequence of length N, that is, the third block sequence to reduce distortion. If the clipped signal value is still higher than the preset peak value, the clipping is continued and recorded in the next signal sequence of length N until the signal values ​​at the midpoints of all block sequences are no greater than the peak value. For example, if the initial signal sequence is [1,4,7,3,6] and the preset peak value is 3, then the enhanced signal sequence corresponding to the initial signal sequence includes the following four block sequences: [1,3,3,3,3], [0,0,0,0,0], [0,1,3,0,3], [0,0,1,0,0], where the signal value at the second position in the initial signal sequence is 7, which exceeds the preset peak value and needs to be clipped twice. The clipped information is recorded in the second position of the third and fourth block sequences.

[0095] In order to further completely illustrate the shear enhancement process described in formula (1), for the initial signal sequence with a length of N, the amplitude of the signal exceeding the preset peak value, and the signal value in the initial signal sequence being less than 0, the present application gives the following examples:

[0096] Assuming that the initial signal sequence is [-6, 4, 7, -3, -1, 2] and the preset peak value is 3, the four block sequences included in the enhanced signal sequence corresponding to the initial signal sequence are respectively: [0, 3, 3, 0, 0, 2], [3, 0, 0, 3, 1, 0], [3, 1, 3, 0, 0, 0], and [0, 0, 1, 0, 0, 0]. The first block sequence records the signal points with positive signal values, and the second block sequence records the signal points with negative signal values. However, since the amplitudes of some signals in the initial signal sequence exceed the peak value, clipping is required. Among them, since the signal value at the 0th position in the initial signal sequence is negative and the amplitude exceeds the peak value, the signal value of 3 needs to be recorded not only at the 0th position in the second block sequence, but also at the 0th position in the third block sequence, in other words, the sum of the signal values at the 0th positions in the second and third block sequences is the signal amplitude at the 0th position in the initial signal sequence.

[0097] Therefore, the enhanced signal sequence obtained through the shear enhancement processing not only retains the amplitude information, positive and negative information, and signal point position information of the initial signal sequence, but also effectively suppresses the clipping distortion caused by the limited peak power, thereby reducing the bit error rate. Moreover, based on the enhanced signal sequence including multiple block sequences obtained through the shear enhancement processing, it is helpful to improve the accuracy of calculating the symbol offset based on the cyclic prefix on the receiving device side, thereby reducing the influence of the time delay on signal recovery and improving the accuracy of light perception ranging and speed measurement, and the synchronization enhancement of optical communication and light perception effect is realized.

[0098] Step 13, taking the signal with a length of at the rear of each block sequence as a cyclic prefix, and copying and adding the cyclic prefix to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, is a preset cyclic prefix length; the length of the block sequence to which the cyclic prefix is added is , = ; the length of the cyclic prefix enhanced signal is .

[0099] In order to eliminate the inter-symbol interference (ISI) caused by the channel multipath effect, the signal with a length of a signal as a cyclic prefix, and the cyclic prefix is added to the front end of the block sequence to obtain a cyclic prefix enhanced signal. The block sequence after adding the cyclic prefix can be expressed as follows:

[0100] (3)

[0101] wherein, represents a signal value of the nth point in a block sequence after adding a cyclic prefix, represents a signal value of the nth point in a block sequence before adding a cyclic prefix. N represents the length of the block sequence before adding the cyclic prefix, and is equal to the length of the initial signal sequence, represents the length of the block sequence after adding the cyclic prefix. Accordingly, the length of the cyclic prefix enhanced signal composed of L block sequences is that is, .

[0102] As an example, assuming that the block sequence is [5, 2, 3, 6, 1], = 2, the block sequence after adding the cyclic prefix is [6, 1, 5, 2, 3, 6, 1].

[0103] Moreover, adding the cyclic prefix in the block sequence is equivalent to creating a periodic extension on the sequence, and this periodicity exhibits the autocorrelation characteristics when performing correlation operations at the receiving end. Therefore, when recovering the signal at the receiving device side, the autocorrelation of the cyclic prefix can be used to determine the symbol offset caused by the time delay. Specifically, when performing correlation calculation on the signal, the correlation value of the cyclic prefix part at the front end of the sequence and the same part at the back end of the sequence will reach a peak, while the correlation between the non-cyclic prefix parts in the sequence is relatively weak, and the correlation value is low or even close to 0. Based on the difference in correlation, by calculating the correlation values of the sequence under different symbol offset conditions, the symbol offset amount can be determined, and then the time delay can be determined, so as to perform ranging and speed measurement between the transmitting device and the receiving device based on the time delay.

[0104] Therefore, by adding the cyclic prefix, not only can the inter-symbol interference caused by the channel multipath effect be effectively eliminated, but also the passive time difference estimation (TDOA, Time Difference of Arrival) sensing can be realized by using the autocorrelation characteristics, that is, the optical sensing ranging and speed measurement can be realized without additional pilot or sensing signals, thereby realizing the deep integration of communication and sensing functions, reducing the system complexity, and saving the spectrum resources.

[0105] In addition, it can be understood that the same cyclic prefix signal can be obtained whether step 12 is performed before step 13 or step 13 is performed before step 12, and therefore the labels of steps 12 and 13 are only used to distinguish different processing procedures and should not be regarded as a limitation on the execution order of the processing procedures.

[0106] Optionally, the length of the cyclic prefix is greater than a maximum delay spread of the channel.

[0107] The maximum delay spread of the channel refers to a maximum value of time delay difference caused by different paths or dispersion effects when a signal propagates in a channel, and can be determined according to a signal propagation environment. In the embodiment of the present application, the length of the cyclic prefix is greater than the maximum delay spread of the channel, which helps to suppress multipath interference.

[0108] Step 14: generating an optical signal based on the cyclic prefix enhanced signal and sending the optical signal to a receiving device.

[0109] Specifically, the cyclic prefix enhanced signal is converted into a current signal by using a digital-to-analog converter, and the optical signal is generated by using the current signal to drive a light source and sent to the receiving device.

[0110] The receiving part comprises:

[0111] Step 21: receiving the optical signal from the sending device and converting the optical signal to obtain a to-be-processed signal sequence.

[0112] The receiving device is provided with a photodetector for receiving the optical signal sent by the sending device, and the optical signal is converted to obtain a to-be-processed signal sequence carrying communication information.

[0113] Step 22: performing inverse shearlet enhancement processing on the to-be-processed signal sequence to obtain a reconstructed signal sequence.

[0114] The inverse shearlet enhancement processing procedure refers to an inverse procedure of the shearlet enhancement procedure in step 12. As can be seen from step 12, the amplitude of each signal point in the initial signal sequence is the sum of the amplitudes of the corresponding signal points in each block sequence, and the positive or negative of each point signal value can be determined according to whether the signal point has an amplitude in the corresponding position in the second block sequence. Therefore, in the inverse shearlet enhancement processing procedure, the amplitudes of each point in the reconstructed signal can be obtained by summing the signal values of the same points in each block to-be-processed sequence, and then the positive or negative of the signal value can be determined.

[0115] As an example, assuming that 3 sub-blocks of the signal sequence to be processed constitute a signal sequence to be processed, respectively: [2, 0, 3, 2, 0], [0, 3, 0, 0, 3], [0, 3, 2, 0, 3], the preset peak value is 3, then the amplitude sequence of the corresponding reconstructed signal is [2, 6, 5, 2, 6], and then the positive and negative of each point of the signal value is judged to obtain the reconstructed signal sequence [2, -6, 5, 2, -6]. The positive and negative values can be directly read and judged, or the first sub-block signal sequence to be processed and the second sub-block signal sequence to be processed are subtracted, and then the sign function is used to judge, which is not limited by the present application.

[0116] However, in actual situations, optical communication channel transmission will cause signal gain and time delay, and thus the signal sequence to be processed obtained by the receiving device side will have a sign offset. In the case of no sign offset, an initial signal sequence carrying communication information corresponds to a signal sequence to be processed with a length of , while in the case of sign offset, an initial signal sequence carrying communication information corresponds to a signal sequence to be processed plus another signal sequence to be processed with a length less than .

[0117] The above-mentioned sign offset will cause the starting point of the true signal sequence to be unable to be determined, and thus the effective communication information cannot be obtained. Therefore, in order to improve the accuracy of the recovered signal, in the inverse shear enhancement process of step 22, the reconstructed signal sequence with a length of corresponding to different sign offsets is calculated, so as to estimate the sign offset in step 23, and then recover the signal.

[0118] Step 23, performing correlation operation on the reconstructed signal sequence to determine the estimated value of the sign offset, and then obtaining an initial recovered signal sequence; wherein the length of the initial recovered signal sequence is .

[0119] When performing correlation calculation on the signal, the correlation value of the cyclic prefix part at the front end of the sequence and the same part at the rear end of the sequence will reach the peak, and the correlation between the non-cyclic prefix parts in the sequence is relatively weak, and the correlation value is low or even close to 0. Based on the difference in correlation, by calculating the correlation values of the sequences under different sign offset conditions, the estimated value of the sign offset can be determined, and then the initial recovered signal sequence including the cyclic prefix and the initial signal sequence can be determined.

[0120] Specifically, the correlation values ​​of different reconstructed signal sequences can be calculated separately, and the symbol offset corresponding to the reconstructed signal sequence with the largest correlation value can be determined as the estimated value; or the different reconstructed signal sequences can be aggregated into one signal sequence, and correlation operations can be performed on different symbol offsets through a sliding window, and the symbol offset corresponding to the value with the largest correlation value can be determined as the estimated value.

[0121] As an example, the estimated value of the symbol offset can be obtained according to the following formula:

[0122] , (4)

[0123] Where ε represents the sign offset, is the estimated value of the symbol offset; is the maximum point function, It indicates that correlation operation is performed on the reconstructed signal sequences corresponding to different symbol offsets.

[0124] Therefore, by utilizing the characteristics of cyclic prefix autocorrelation, accurate estimation of symbol offset can be achieved during signal recovery, effectively reducing the impact of delay on communication and improving communication reliability.

[0125] Step 24: Remove the cyclic prefix from the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence.

[0126] It is understandable that the target recovery signal obtained by the receiving device in step 24 corresponds to the initial signal sequence of the sending device in step 11, so the purpose of step 24 is to restore the initial signal sequence. Specifically, the initial recovery signal sequence consists of a length of The cyclic prefix and the effective signal part of length N are composed of the cyclic prefix and the effective signal part of length N. The cyclic prefix removal refers to removing the initial recovery signal sequence. The target signal is recovered by combining signal points of lengths. This process helps eliminate interference introduced by multipath effects and ensures signal integrity.

[0127] Step 25: Perform information recovery processing on the target recovery signal to obtain communication information.

[0128] Performing information recovery processing on the target recovery signal refers to extracting communication information from the target recovery signal, which is the inverse process of step 11. Specific processing methods include but are not limited to fast Fourier transform, serial-to-parallel conversion, demodulation, etc.

[0129] Step 26: Determine the delay according to the estimated value of the symbol offset.

[0130] In the embodiment of the present invention, the initial signal sequence is obtained based on OFDM technology, and OFDM is obtained by dividing the preset bandwidth into The data transmission is realized by dividing into multiple orthogonal subcarriers, and correspondingly, the sampling interval of the OFDM symbol, i.e. the initial signal sequence, is 1 / B, and the sampling interval of the reconstructed signal is also 1 / B. In the case of determining the symbol offset, the time delay can be expressed as follows:

[0131] , (5)

[0132] wherein, denotes the time delay, denotes the estimated value of the symbol offset obtained in step 23.

[0133] Step 27, determining the distance and relative speed between the sending device and the receiving device according to the time delay.

[0134] In the case of determining the time delay, the distance between the sending device and the receiving device can be expressed as follows:

[0135] , (6)

[0136] wherein, c denotes the speed of light.

[0137] The speed of the receiver can be measured by repeating step 26 twice. Specifically, the first time, the estimated value of the symbol offset is , the distance measured by the time delay corresponding to the symbol offset is . After a time , the estimated value of the second symbol offset is , and the measured distance is .

[0138] The relative speed between the sending device and the receiving device can be expressed as follows:

[0139] , (7)

[0140] Therefore, by adding the cyclic prefix in the signal sequence and using the characteristics of the cyclic prefix autocorrelation to calculate the estimated value of the symbol offset, passive time difference estimation sensing can be realized without additional pilots or sensing signals, and then optical sensing ranging and speed measurement can be realized, achieving deep integration of optical communication and sensing functions, reducing system complexity, and saving spectrum resources.

[0141] In summary, the embodiment of the present application provides a method for integrating optical communication and sensing based on cyclic prefix clipping enhancement. In the sending part, the initial signal sequence carrying communication information obtained is subjected to clipping enhancement processing and addition of a cyclic prefix to obtain a cyclic prefix enhanced signal, and then the cyclic prefix enhanced signal is converted into an optical signal and sent to a receiving device. In the receiving part, after the inverse clipping enhancement processing of the signal sequence obtained after the receiving is converted to obtain a reconstructed signal sequence, the correlation operation of the reconstructed signal sequence based on the cyclic prefix is performed to determine the estimated value of the symbol offset, and then the initial recovered signal sequence is obtained, and after the removal of the cyclic prefix and the information recovery processing, the communication information can be obtained to realize the communication function. At the same time, according to the estimated value of the symbol offset, the time delay of the optical communication can be further determined, and then the distance and relative speed between the sending device and the receiving device are determined according to the time delay to realize the optical sensing ranging and speed measurement.

[0142] In the above manner, by adding a cyclic prefix, not only can the inter-symbol interference caused by the channel multipath effect be effectively eliminated, but also the passive time difference estimation (TDOA, Time Difference of Arrival) sensing can be realized by using the autocorrelation characteristics, without additional pilots or sensing signals, so that the deep integration of communication and sensing functions is realized, the system complexity is reduced, and the spectrum resources are saved. At the same time, by using the clipping enhancement processing, not only the communication information is effectively preserved, but also the clipping distortion caused by the limited peak power is suppressed, the bit error rate is reduced, and the accuracy of calculating the symbol offset according to the cyclic prefix is improved, thereby reducing the influence of the time delay on the signal recovery and improving the accuracy of the optical sensing ranging and speed measurement, and the synchronous enhancement of the optical communication and optical sensing effects is realized.

[0143] Optionally, the step 11 comprises:

[0144] Step 111, target bit stream information is generated, and the target bit stream information is mapped into a complex value symbol sequence according to a preset modulation mode; wherein the target bit stream information carries communication information;

[0145] Step 112, inverse fast Fourier transform is performed on the complex value symbol sequence to obtain parallel time domain signals;

[0146] Step 113, parallel to serial conversion is performed on the parallel time domain signals to obtain a serial time domain signal sequence;

[0147] Step 114, power control is performed on the serial time domain signal sequence to obtain an initial signal sequence.

[0148] The power factor is introduced to control the signal, which can control the signal strategy and the degree of clipping distortion through power scaling, and can amplify the signal power when the signal amplitude is too small, so as to reduce the influence of noise and interference signals.

[0149] Figure 2 Another step flow chart of the embodiment of the application is given, which is based on the cyclic prefix shear enhancement of the integrated method of optical communication and perception, wherein the formula and symbol included are consistent with the formula and symbol in the embodiment of the application. Figure 2 The step flow chart of the embodiment of the method described in steps 111-114 is included.

[0150] Corresponding to step 111, a bit stream carrying communication information is generated by the signal source, and the bit stream is mapped into a complex symbol sequence according to the mapping mode of M-QAM. Wherein, N is the number of subcarriers, and also the length of the initial signal sequence, and the complex symbol sequence needs to satisfy Hermite symmetry to ensure that the parallel time domain signal output by the inverse fast Fourier transform is real.

[0151] Corresponding to step 114, the power factor is introduced to perform power control, so as to obtain the initial signal sequence.

[0152] Optionally, the step 21 comprises:

[0153] Step 211, receiving the optical signal sent by the sending device, and converting the optical signal into an electrical signal;

[0154] Step 212, inputting the electrical signal into an analog-digital converter to obtain an initial signal sequence to be processed;

[0155] Step 213, inputting the initial signal sequence to be processed into a digital signal processor for modeling processing to obtain a signal sequence after modeling;

[0156] Step 214, segmenting the signal sequence after modeling according to the length to obtain a signal sequence to be processed, and then segmenting the signal sequence to be processed according to the length to obtain a segmented signal sequence to be processed.

[0157] Regarding step 211, the receiving device is provided with a photodetector (PD) for receiving the incident optical signal sent by the sending device and converting the incident optical signal into an electrical signal.

[0158] Regarding step 213, the initial signal sequence to be processed is inputted into a digital signal processor (DSP) for modeling according to a preset model to obtain a signal sequence after modeling .

[0159] As an example, the initial signal sequence to be processed can be modeled according to the following formula:

[0160] y s = p. ̃ h s * x Figure 2 s + w y [s] , (8)

[0161] in, Represents the signal value of the sth point in the modeled signal sequence, Represents the signal value of the sth point in the initial signal sequence to be processed; Represents the unit impulse response of the preset model, represents the responsivity of the photodetector, w y [ s ] Represents additive noise. It should be noted that, in the embodiment of the present invention, “ ” is only used in formula (8) and is represented as the convolution operator. ” are all multiplication operators.

[0162] Regarding step 214, you can use y m [l,p] represents the signal value of the p-th point in the l-th block of the m-th sequence to be processed, where p ranges from 0 to N-1, and l ranges from 0 to L-1. m, l, and p can be obtained according to the following formulas:

[0163] , (9)

[0164] , (10)

[0165] , (11)

[0166] Wherein, s is the same as that in step 213. The s in has the same meaning, indicating the sth signal point in the modeled signal sequence; represents the rounding function, It represents the remainder of a over b.

[0167] Optionally, based on the contents of steps 211 to 214, the reconstructed signal sequence in step 22 may be expressed according to the following formula:

[0168] , (12)

[0169] in, Indicates the sign offset, Indicates that the symbol offset is In the case of , the signal value of the p-th point in the m-th reconstructed signal sequence; Represents the mth sample sequence to be processed; represents the rounding function, represents the remainder of a over b, represents a symbolic function. For example, Indicates the mth sample sequence to be processed The first block in the sequence The value of a signal point.

[0170] Reference Figure 2 middle to The flowchart of the steps describes the process of inverse shear enhancement using the method described in formula (12), that is, Figure 2 Zhongyou to The reverse process of the shear enhancement process.

[0171] It is worth noting that in the signal transmission part, the embodiment of the present invention first performs the initial signal sequence Enhanced signal sequence was obtained by splicing enhancement , and then enhance the signal sequence Add a cyclic prefix (CP) to obtain a cyclic prefix enhanced signal sequence In the receiving part, inverse clipping and enhancement are performed before cyclic prefix removal. This is because the cyclic prefix must be retained for symbol offset estimation. Performing inverse clipping and enhancement first can effectively reduce the computational complexity during signal recovery, improving communication efficiency, compared to estimating the symbol offset first.

[0172] In addition, although Figure 3 Simplified the Segment processing to obtain y m [ l ,p] However, this process is very important for the inverse shear enhancement process. Using segmented processing to obtain the signal sequence to be processed can effectively simplify the processing process and improve the interpretability of the inverse shear enhancement process.

[0173] Figure 2 A flow chart of the inverse shear enhancement processing provided by an embodiment of the present application is given, taking a signal sequence with length 18 as an example. Two sequences to be processed are obtained by segmenting the signal sequence, i.e. , L = 3, where one sequence to be processed includes 3 sub-blocks to be processed, and the other sequence to be processed includes 1 sub-block to be processed. y m [ l ,p] represents the lth sub-block to be processed in the mth sequence to be processed, and p represents the position of a signal point in the sub-block to be processed, for example y 0 [1, p ] , y 0 [2, p ] , y 1 [0, p ] ; represents the signal value of the pth point in the lth sub-block to be processed in a certain sequence to be processed, for example , and the like. As shown in equation (12), represents the mth reconstructed signal sequence when the symbol offset is , and p represents the position of a signal point in the reconstructed signal sequence, for example , and the like; [p, ] represents the signal value of the pth point in the reconstructed signal sequence when the symbol offset is . Different colored boxes are used to identify the processing process of the reconstructed signal sequence corresponding to different symbol offsets.

[0174] It can be understood that, to calculate a reconstructed signal sequence with length , a sequence with length is needed. Therefore, to calculate the reconstructed signal sequence when the symbol offset is 0, the 0th~14th signals, i.e. ~ ​​​​The 15 signals are divided into three block sequences in order, and are processed according to the method described in formula (12), so that the reconstructed signal sequence under the condition of symbol offset 0 is obtained. Taking [0, 0] as an example, The positive and negative values of the signal are determined by the difference between the signal values of the corresponding points in the first block sequence and the second block sequence.

[0175] Optionally, based on the reconstructed signal sequence obtained according to formula (12), the step 23 comprises:

[0176] Step 231, determining the estimated value of the symbol offset by performing correlation operation on the reconstructed signal sequence according to the following formula:

[0177] , (13)

[0178] Wherein, represents the signal value of the i th point in the m th reconstructed signal sequence under the condition of symbol offset . is the estimated value of the symbol offset, is the length of the sliding window; is the maximum point function;

[0179] Step 232, determining the initial recovered signal sequence according to the estimated value of the symbol offset.

[0180] As an example, it is assumed that the reconstructed signal sequences obtained under the conditions of symbol offset 0, 1 and 2 are [2, 0, 3, 2, 1], [0, 3, 2, 1, 3] and [3, 2, 1, 3, 2] respectively, N = 3, and the length of the sliding window is 2. Based on each reconstructed signal sequence respectively, the result corresponding to the 0 th reconstructed signal sequence is , the result corresponding to the 1 st reconstructed signal sequence is , and the result corresponding to the 2 nd reconstructed signal sequence is . Therefore, the correlation value of the reconstructed signal sequence is the highest under the condition of offset 2, so the estimated result of the symbol offset is determined as 2. Accordingly, the 2 nd reconstructed signal sequence can be determined as the initial recovered signal sequence. At the same time, the signal values of the first two points and the last two points in the 2 nd reconstructed signal sequence [3, 2, 1, 3, 2] are the same, which meets the requirement of the cyclic prefix, indicating that the estimated value of the symbol offset is correct.

[0181] As Figure 2As shown in the sensing part, the initial recovered signal sequence can be determined according to the returned estimation of the symbol offset, which helps to realize the communication function; meanwhile, the time delay can be further determined according to the estimation of the symbol offset, and then the optical sensing ranging and speed measurement are realized, which realizes the integration of the optical communication sensing function.

[0182] Therefore, the autocorrelation of the cyclic prefix helps to realize the passive time difference estimation sensing in the optical communication sensing process, and the deep integration of the communication and sensing functions can be realized without additional pilots or sensing signals, thereby saving the spectrum resources.

[0183] Optionally, the length of the sliding window in formula (13) is .

[0184] Selecting the length of the cyclic prefix as the length of the sliding window helps to make full use of the correlation of the cyclic prefix and improve the accuracy of the symbol offset estimation.

[0185] Optionally, the step 25 comprises:

[0186] Step 251, converting the initial recovered signal sequence into parallel initial recovered signals;

[0187] Step 252, performing fast Fourier transform on the parallel initial recovered signals to obtain initial recovered signals in the frequency domain;

[0188] Step 253, processing the initial recovered signals in the frequency domain by using a first-order equalizer to obtain equalized initial recovered signals;

[0189] Step 254, demodulating the equalized initial recovered signals according to a preset demodulation mode to obtain the communication information.

[0190] As an example, Figure 4 A step flowchart of the method embodiment of steps 24, 251-254 is also given in the specification.

[0191] Regarding steps 24 and 251, after obtaining the initial recovered signal sequence by removing the cyclic prefix, before performing the serial-parallel conversion, corresponding processing is performed according to whether the receiving part has performed power control: if a power factor is introduced in the receiving part for power control, corresponding inverse processing is needed, and if not, inverse processing of power control is not needed.

[0192] Regarding step 253, the main function of the first-order equalizer is to compensate for the signal distortion caused by multipath propagation, thereby improving the quality of the signal. By equalizing the recovered time domain signal, the intersymbol interference can be effectively reduced, and the clarity and reliability of the received signal can be improved.

[0193] Regarding step 254, M-QAM demodulation is performed on the equalized initial recovered signal. Through demodulation, the receiving end can accurately recover the transmitted bit stream information, and the information source receives the bit stream information and then obtains the communication information, thereby achieving a communication effect.

[0194] Optionally, the sending part further includes: when there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and the signal values ​​of the midpoints of the initial signal sequence are not less than zero, L is equal to 1;

[0195] When there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and there is a point with a signal value less than zero in the initial signal sequence, L is equal to 2.

[0196] When L=1 or 2, the communication strategy can be adjusted according to the actual situation. For example, when the environmental interference is small, the initial signal sequence can be sent directly; when the environmental interference is strong, the signal amplitude can be amplified through power control, and then the signal can be sent after the processing such as clipping enhancement and adding cyclic prefix described in the above steps to reduce the interference of environmental interference on the effective information in the signal.

[0197] Figure 5 A structural block diagram of an integrated optical communication perception system based on cyclic prefix clipping enhancement provided by an embodiment of the present invention is provided. The system 300 includes a sending device 310 and a receiving device 320, wherein the sending device includes:

[0198] The signal generating module 311 is configured to generate at least one initial signal sequence of length N carrying communication information, where N is a positive integer;

[0199] The shear enhancement module 312 is used to determine whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence. When there is a signal with an amplitude exceeding the preset peak value in the initial signal sequence, the initial signal sequence is shear enhanced using the following formula to obtain a value of length The enhanced signal sequence is divided into L block sequences, where the length of the block sequence is N, and L is an integer not less than 3:

[0200] ,

[0201] in, Indicates the mth enhanced signal sequence The signal value of the point, The value is ; Indicates the mth initial signal sequence The signal value of the point When 0~N-1 is taken, is a preset peak value, used for clipping processing on the initial signal sequence; is 0; is a preset peak value, used for clipping processing on the initial signal sequence; is 0; is a preset peak value, used for clipping processing on the initial signal sequence; is represented as the following formula:

[0202] ;

[0203] The cyclic prefix adding module 313 is configured to add a signal with a length of as a cyclic prefix at the back of each block sequence, and copy and add the cyclic prefix to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, is a preset cyclic prefix length; the length of the block sequence to which the cyclic prefix is added is , ; the length of the cyclic prefix enhanced signal is ;

[0204] The signal conversion and sending module 314 is configured to generate an optical signal based on the cyclic prefix enhanced signal and send the optical signal to a receiving device.

[0205] The receiving device comprises:

[0206] The signal receiving and conversion module 321 is configured to receive the optical signal from the sending device and convert the optical signal to obtain a to-be-processed signal sequence.

[0207] The signal reconstruction module 322 is configured to perform inverse clipping enhancement processing on the to-be-processed signal sequence to obtain a reconstructed signal sequence.

[0208] The correlation calculation module 323 is configured to perform correlation operation on the reconstructed signal sequence to determine an estimated value of the symbol offset, and further obtain an initial recovered signal sequence; wherein, the length of the initial recovered signal sequence is ;

[0209] The cyclic prefix removing module 324 is configured to remove the cyclic prefix in the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence.

[0210] The information recovery module 325 is configured to perform information recovery processing on the target recovered signal to obtain communication information.

[0211] The delay determination module 326 is configured to determine a delay according to the estimated value of the symbol offset.

[0212] ​The distance and speed measurement module 327 is configured to determine the distance and relative speed between the sending device and the receiving device according to the time delay.

[0213] To illustrate the technical effects of the above-mentioned optical communication perception integrated method and system based on cyclic prefix clipping enhancement, the embodiment of the present invention provides the following simulation parameters and data results:

[0214] Table 1 Simulation parameters

[0215]

[0216] Figure 5 A comparative chart shows simulation results for communication perception of three different systems under specific conditions provided by embodiments of the present invention. These systems are: an asymmetrically clipped optical (ACO) OFDM system, a DC biased optical (DCO) OFDM system, and a Clipping Enhanced Optical-Orthogonal Frequency Division Multiplexing (CEO-OFDM) system provided by embodiments of the present invention. All three systems communicate by adding a cyclic prefix. Indicates the power index, which is used to control the signal power.

[0217] Figure 6 Specifically, it is shown in different The bit error rate (BER) and the perception error of passive time difference estimation (TDOA) of DCO-OFDM, ACO-OFDM and CEO-OFDM systems are analyzed by simulation. The results show that as Increase, BER first decreases and then increases, the reason is that the initial power increase can improve the signal to noise ratio, while too large The introduction of clipping noise will cause the bit error rate to increase. This is due to the improved correlation brought about by the enhanced signal power. Regardless of BER or TDOA, the CEO-OFDM system provided by the present invention always shows the best perception accuracy.

[0218] Figure 7 The figure shows the joint estimation result of the distance and speed of a single target obtained by the optical communication perception integrated system provided by the embodiment of the present invention in a simulation scenario.Figure 8 A distribution diagram of the single target distance estimation result obtained by the optical communication and perception integrated system provided by the embodiment of the present application in a simulation scenario is given, Figures 6-8 A distribution diagram of the single target speed estimation result obtained by the optical communication and perception integrated system provided by the embodiment of the present application in a simulation scenario is given. In other words, in the simulation scenario of the CEO-OFDM system, Figure 6 The distance and speed joint estimation result diagram of the single target is constituted.

[0219] Figure 7 In the figure, the blue triangle represents the estimation result of the CEO-OFDM, the red ellipse is a 3-sigma range, used to indicate the confidence boundary of the estimation error; the blue dot represents the true distance and speed. Figure 8 and ​ The marginal distribution diagram of the distance and speed estimation result is shown, which shows the concentration of the estimation result in two dimensions. The results show that the CEO-OFDM system can realize high-precision estimation of the target distance and speed under this simulation condition, and the error is concentrated in the vicinity of the target, verifying the effectiveness and robustness of the method described in the present application in the joint perception scene.

[0220] In addition, the terms “first”, “second” are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with “first”, “second” can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of “multiple” is two or more, unless otherwise specifically limited.

[0221] Although the embodiments of the present application have been shown and described above, it can be understood that the above-mentioned embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above-mentioned embodiments without departing from the principles and purposes of the present application within the scope of the present application.

Claims

1. An integrated optical communication perception method based on cyclic prefix clipping enhancement, characterized in that: The method includes a sending part and a receiving part; the sending part includes: Step 11: Generate at least one initial signal sequence of length N carrying communication information, where N is a positive integer; Step 12: Determine whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence. If there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence, perform shear enhancement processing on the initial signal sequence using the following formula to obtain a value with a length of The enhanced signal sequence is divided into L block sequences, where the length of the block sequence is N, and L is an integer not less than 3: ， in, Indicates the mth enhanced signal sequence The signal value of the point, The value is ; Indicates the mth initial signal sequence The signal value of the point When 0~N-1 is taken, is the actual signal value, when Pick hour, The value is 0; is the preset peak value; It is expressed as the following formula: ； Step 13: The length of the rear part of each block sequence is The signal is used as a cyclic prefix, and the cyclic prefix is ​​copied and added to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, is the preset cyclic prefix length; the length of the block sequence with the cyclic prefix added is , = ; The length of the cyclic prefix enhanced signal is ; Step 14: Generate an optical signal based on the cyclic prefix enhanced signal and send the optical signal to a receiving device; The receiving part includes: Step 21: receiving the optical signal from the transmitting device and converting the optical signal to obtain a signal sequence to be processed; Step 22: performing inverse shearing enhancement processing on the signal sequence to be processed to obtain a reconstructed signal sequence; The reconstructed signal sequence is expressed according to the following formula: ， in, Indicates the sign offset, Indicates that the symbol offset is In the case of , the signal value of the p-th point in the m-th reconstructed signal sequence; Represents the mth sample sequence to be processed; represents the rounding function, represents the remainder of a over b, represents a symbolic function; Step 23: perform a correlation operation on the reconstructed signal sequence to determine the estimated value of the symbol offset, thereby obtaining an initial restored signal sequence; wherein the length of the initial restored signal sequence is ; Step 24: remove the cyclic prefix from the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence; Step 25: Perform information recovery processing on the target recovery signal to obtain communication information; Step 26: Determine the delay according to the estimated value of the symbol offset; Step 27: Determine the distance and relative speed between the sending device and the receiving device according to the time delay.

2. The optical communication sensing integrated method according to claim 1, characterized in that: The step 11 includes: Generate target bit stream information, and map the target bit stream information into a complex-valued symbol sequence according to a preset modulation method; wherein the target bit stream information carries communication information; Performing an inverse fast Fourier transform on the complex-valued symbol sequence to obtain parallel time-domain signals; Performing parallel-to-serial conversion on the parallel time-domain signals to obtain a serial time-domain signal sequence; Power control is performed on the serial time-domain signal sequence to obtain an initial signal sequence.

3. The optical communication sensing integrated method according to claim 1, characterized in that: The length of the cyclic prefix is ​​greater than the maximum delay spread of the channel.

4. The optical communication sensing integrated method according to claim 1, characterized in that: The step 21 includes: receiving an optical signal sent by a transmitting device and converting the optical signal into an electrical signal; Inputting the electrical signal into an analog-to-digital converter to obtain an initial signal sequence to be processed; Inputting the initial signal sequence to be processed into a digital signal processor for modeling processing to obtain a modeled signal sequence; According to length The signal sequence after modeling is segmented to obtain a signal sequence to be processed, and then the signal sequence is segmented according to the length. The signal sequence to be processed is segmented to obtain a segmented signal sequence to be processed.

5. The optical communication sensing integrated method according to claim 1, characterized in that: The step 23 includes: The estimated value of the symbol offset is determined by performing a correlation operation on the reconstructed signal sequence according to the following formula: ， in, Indicates that the symbol offset is In the case of , the signal value of the i-th point in the m-th reconstructed signal sequence; is the estimated value of the sign offset, is the length of the sliding window; is the maximum point function; An initial recovered signal sequence is determined according to the estimated value of the symbol offset.

6. The optical communication sensing integrated method according to claim 5, characterized in that: The length of the sliding window is .

7. The optical communication sensing integrated method according to claim 1, characterized in that: The step 25 includes: Converting the initial recovery signal sequence into parallel initial recovery signals; Performing a fast Fourier transform on the parallel initial recovery signals to obtain initial recovery signals in the frequency domain; Processing the initial restored signal in the frequency domain using a first-order equalizer to obtain an equalized initial restored signal; The equalized initial recovery signal is demodulated according to a preset demodulation method to obtain the communication information.

8. The optical communication sensing integrated method according to claim 1, characterized in that: The sending part further includes: when there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and the signal value of each point in the initial signal sequence is not less than zero, L is equal to 1; When there is no signal with an amplitude exceeding a preset peak value in the initial signal sequence, and there is a point with a signal value less than zero in the initial signal sequence, L is equal to 2.

9. An integrated optical communication perception system based on cyclic prefix clipping enhancement, characterized in that: The system includes a sending device and a receiving device; The sending device includes: A signal generating module, configured to generate at least one initial signal sequence of length N carrying communication information, where N is a positive integer; The shear enhancement module is used to determine whether there is a signal with an amplitude exceeding a preset peak value in the initial signal sequence. When there is a signal with an amplitude exceeding the preset peak value in the initial signal sequence, the initial signal sequence is sheared and enhanced by the following formula to obtain a value of length The enhanced signal sequence is divided into L block sequences, where the length of the block sequence is N, and L is an integer not less than 3: ， in, Indicates the mth enhanced signal sequence The signal value of the point, The value is ; Indicates the mth initial signal sequence The signal value of the point When 0~N-1 is taken, is the actual signal value, when Pick hour, The value is 0; is a preset peak value used to perform trimming processing on the initial signal sequence; It is expressed as the following formula: ； The cyclic prefix adding module is used to add a cyclic prefix to each block sequence. The signal is used as a cyclic prefix, and the cyclic prefix is ​​copied and added to the front end of the corresponding block sequence to obtain a cyclic prefix enhanced signal; wherein, is the preset cyclic prefix length; the length of the block sequence with the cyclic prefix added is , = +N; the length of the cyclic prefix enhanced signal is ; a signal conversion and sending module, configured to generate an optical signal based on the cyclic prefix enhanced signal and send the optical signal to a receiving device; The receiving device includes: a signal receiving and converting module, configured to receive the optical signal from the transmitting device and convert the optical signal to obtain a signal sequence to be processed; A signal reconstruction module, configured to perform inverse shearing enhancement processing on the signal sequence to be processed to obtain a reconstructed signal sequence; The reconstructed signal sequence is expressed according to the following formula: ， in, Indicates the sign offset, Indicates that the symbol offset is In the case of , the signal value of the p-th point in the m-th reconstructed signal sequence; Represents the mth sample sequence to be processed; represents the rounding function, represents the remainder of a over b, represents a symbolic function; A correlation calculation module is used to perform a correlation operation on the reconstructed signal sequence to determine an estimated value of the symbol offset, thereby obtaining an initial restored signal sequence; wherein the length of the initial restored signal sequence is ; a cyclic prefix removal module, configured to remove the cyclic prefix from the initial recovered signal sequence to obtain a target recovered signal corresponding to the initial signal sequence; An information recovery module, configured to perform information recovery processing on the target recovery signal to obtain communication information; A delay determination module, configured to determine the delay according to the estimated value of the symbol offset; The distance and speed measurement module is used to determine the distance and relative speed between the sending device and the receiving device according to the time delay.

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