An integrated signal processing method, device and storage medium

Abstract

The application discloses an integrated signal processing method and device and a storage medium, and comprises the following steps: obtaining a spectrum decision sequence when modulating an NC-OFDM communication sensing integrated signal; determining vacant subcarriers according to the spectrum decision sequence; and performing two-dimensional FFT signal processing on the integrated signal according to the determined vacant subcarriers to obtain the distance and speed of a target. According to the application, the distance and speed of the target can be estimated when some subcarriers are vacant, the influence of noise and interference can be resisted, the influence of noise on the ranging result is reduced, and suitable subcarriers are selected for speed estimation.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to an integrated signal processing method, apparatus and storage medium. Background Technology

[0002] In the field of ISAC (Integrated Sensing and Communication) technology, this specifically involves the design of radar signal processing algorithms for integrated waveforms using NC-OFDM (non-contiguous OFDM; OFDM: Orthogonal Frequency Division Multiplexing) to address spectrum holes. With the widespread adoption of wireless electronic devices, the electromagnetic environment is becoming increasingly congested and complex, making spectrum congestion a critical issue. "Spectrum holes" refer to non-contiguous spectrum scenarios. This is because, in practical applications, the presence of higher-priority users or other strong interference causes the channel to exhibit frequency selectivity. In such scenarios, continuous frequency bands cannot be used; only non-contiguous spectrum can be utilized for information transmission.

[0003] The shortcoming of existing technologies is that, based on the integrated sensing signal of NC-OFDM communication in discontinuous spectrum scenarios, the distance and velocity of the target cannot be estimated when some subcarriers are idle. Summary of the Invention

[0004] This invention provides an integrated signal processing method, apparatus, and storage medium to solve the problem that, in NC-OFDM communication sensing integrated signals based on discontinuous spectrum scenarios, the distance and velocity of the target cannot be estimated when some subcarriers are idle.

[0005] This invention provides the following technical solutions:

[0006] An integrated signal processing method, comprising:

[0007] Acquire the spectrum decision sequence when modulating the integrated sensing signal of NC-OFDM communication;

[0008] The vacant subcarriers are determined based on the spectrum decision sequence;

[0009] The distance and velocity of the target are obtained by performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers.

[0010] In practice, the spectrum decision sequence is obtained based on spectrum sensing.

[0011] In practice, the integrated signal undergoes two-dimensional FFT signal processing based on the determined vacant subcarriers, including one or a combination of the following processes:

[0012] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0013] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0014] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0015] In implementation, when constructing the channel information matrix, vacant subcarriers are located using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0, including:

[0016] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0017] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0018] In practice, when using the column vectors of the channel information matrix for ranging, and determining the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence, after constructing the channel information matrix, the column vectors are used for energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0019] In implementation, after constructing the channel information matrix, energy aggregation is performed on the column vectors, and then IDFT is performed using the updated column vectors to obtain the peak index corresponding to the time delay, including:

[0020] Input channel information matrix;

[0021] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0022] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0023] Sum the IDFT results of the ranging vectors;

[0024] After performing a peak search, output the peak index.

[0025] In practice, when selecting subcarriers for velocity estimation based on the vacant subcarriers reflected by the spectrum decision sequence, row vectors are used for carrier screening to obtain row vectors carrying channel information. DFT is then performed on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity.

[0026] In implementation, row vectors are used for carrier filtering to obtain row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0027] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0028] Channel information for speed measurement is carried on non-empty subcarriers;

[0029] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0030] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0031] An integrated signal processing device, comprising:

[0032] The processor is used to read programs from memory and execute the following procedures:

[0033] Acquire the spectrum decision sequence when modulating the integrated sensing signal of NC-OFDM communication;

[0034] The vacant subcarriers are determined based on the spectrum decision sequence;

[0035] The distance and velocity of the target are obtained by performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers;

[0036] A transceiver is used to receive and send data under the control of a processor.

[0037] In practice, the spectrum decision sequence is obtained based on spectrum sensing.

[0038] In practice, the integrated signal undergoes two-dimensional FFT signal processing based on the determined vacant subcarriers, including one or a combination of the following processes:

[0039] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0040] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0041] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0042] In implementation, when constructing the channel information matrix, vacant subcarriers are located using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0, including:

[0043] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0044] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0045] In practice, when using the column vectors of the channel information matrix for ranging, and determining the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence, after constructing the channel information matrix, the column vectors are used for energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0046] In implementation, after constructing the channel information matrix, energy aggregation is performed on the column vectors, and then IDFT is performed using the updated column vectors to obtain the peak index corresponding to the time delay, including:

[0047] Input channel information matrix;

[0048] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0049] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0050] Sum the IDFT results of the ranging vectors;

[0051] After performing a peak search, output the peak index.

[0052] In practice, when selecting subcarriers for velocity estimation based on the vacant subcarriers reflected by the spectrum decision sequence, row vectors are used for carrier screening to obtain row vectors carrying channel information. DFT is then performed on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity.

[0053] In implementation, row vectors are used for carrier filtering to obtain row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0054] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0055] Channel information for speed measurement is carried on non-empty subcarriers;

[0056] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0057] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0058] An integrated signal processing device, comprising:

[0059] The sequence module is used to acquire the spectrum decision sequence when modulating the NC-OFDM communication sensing integrated signal;

[0060] The subcarrier module is used to determine the vacant subcarriers based on the spectrum decision sequence;

[0061] The processing module is used to perform two-dimensional FFT signal processing on the integrated signal based on the determined idle subcarriers to obtain the target's distance and velocity.

[0062] In practice, the sequence module is further used to obtain a spectrum decision sequence based on spectrum sensing.

[0063] In implementation, the processing module is further configured to perform one or a combination of the following processes when performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers:

[0064] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0065] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0066] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0067] In implementation, the processing module is further used to locate vacant subcarriers through the spectrum decision sequence when constructing the channel information matrix, and to set the symbols carried on the corresponding subcarriers to 0, including:

[0068] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0069] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0070] In practice, the processing module is further used to determine the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence when ranging using the column vectors of the channel information matrix. After constructing the channel information matrix, the column vectors are used to perform energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0071] In implementation, the processing module is further used to, after constructing the channel information matrix, perform energy aggregation on the column vectors, and then use the updated column vectors to perform IDFT to obtain the peak index corresponding to the time delay, including:

[0072] Input channel information matrix;

[0073] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0074] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0075] Sum the IDFT results of the ranging vectors;

[0076] After performing a peak search, output the peak index.

[0077] In practice, the processing module is further used to perform carrier filtering by taking row vectors when selecting subcarriers for velocity estimation based on the empty subcarriers reflected by the spectrum decision sequence, to obtain row vectors carrying channel information, and to perform DFT on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and estimate the velocity.

[0078] In implementation, the processing module is further used to extract row vectors for carrier filtering, obtaining row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0079] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0080] Channel information for speed measurement is carried on non-empty subcarriers;

[0081] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0082] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0083] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned integrated signal processing method.

[0084] The beneficial effects of this invention are as follows:

[0085] In the technical solution provided by the embodiments of the present invention, a spectrum decision sequence is obtained when the NC-OFDM communication sensing integrated signal is modulated, and the target's distance and velocity are obtained by performing two-dimensional FFT signal processing on the integrated signal based on the determined idle subcarriers. The NC-OFDM communication sensing integrated signal obtains a spectrum decision sequence based on spectrum sensing during modulation. Unlike the existing NC-OFDM communication sensing integrated system, this sequence is not only used to assist in the generation of the integrated signal, but also to assist in the radar signal processing process. Therefore, the target's distance and velocity can be estimated when some subcarriers are idle.

[0086] Furthermore, in this auxiliary radar signal processing process, the spectrum decision sequence-assisted radar signal processing mainly involves one or a combination of the following processes:

[0087] Spectrum decision: When constructing the channel information matrix, the vacant subcarriers are located by the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are manually set to 0. This process is used to combat the effects of noise and interference.

[0088] Energy aggregation: When ranging using the column vectors of the channel information matrix, the number of OFDM symbols requiring energy aggregation is determined based on the number of vacant subcarriers reflected in the spectrum decision sequence. Energy aggregation of multiple symbols increases the energy of the channel information terms and reduces the impact of noise on the ranging results.

[0089] Carrier selection: Unused subcarriers cannot be used for ranging and velocity measurement because they do not contain channel information. Appropriate subcarriers need to be selected for velocity estimation based on the spectrum decision sequence. Attached Figure Description

[0090] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0091] Figure 1 This is a schematic diagram of the two-dimensional FFT signal processing flow in an embodiment of the present invention;

[0092] Figure 2 This is a schematic diagram illustrating the implementation process of the integrated signal processing method in an embodiment of the present invention;

[0093] Figure 3 This is a schematic diagram of signal processing for spectral holes in an embodiment of the present invention;

[0094] Figure 4 This is a schematic diagram of the spectrum decision process in an embodiment of the present invention;

[0095] Figure 5 This is a schematic diagram of the energy polymerization process in an embodiment of the present invention;

[0096] Figure 6 This is a schematic diagram of the carrier selection process in an embodiment of the present invention;

[0097] Figure 7 This is a schematic diagram of the integrated signal processing device in an embodiment of the present invention. Detailed Implementation

[0098] The inventor noticed the following during the invention process:

[0099] Radar signal processing mainly involves processing echo signals and integrated transmitted signals to obtain information such as target range and velocity. Existing OFDM (Orthogonal Frequency Division Multiplexing) integrated signal processing algorithms mainly include two-dimensional FFT (Fast Fourier Transform) and cyclic correlation algorithms.

[0100] The integrated OFDM-based transmission signal can be written as:

[0101]

[0102] Where N is the number of subcarriers, M is the number of symbols, Δf is the subcarrier spacing, and d m,n It is the modulation symbol carried on the nth subcarrier of the mth OFDM symbol.

[0103] After passing through the channel, the received echo signal can be written as:

[0104]

[0105] Where N is the number of subcarriers, M is the number of symbols, Δf is the subcarrier spacing, and d m,n It is the modulation symbol carried on the nth subcarrier of the m-th OFDM symbol, τ is the time delay, and f d It is the Doppler frequency shift, ω n It is Gaussian white noise.

[0106] The processing flow of the two-dimensional FFT algorithm is briefly described below:

[0107] The echo signal obtained after sampling can be represented as:

[0108] d Rx (mN+n)=H(m,n)d Tx (mN+n)×exp(-j2πnΔfτ)exp(-j2πmT b f d ),

[0109] Where, d Rx (mN+n) and d Tx (mN+n) represent the data information d carried on the nth subcarrier of the m-th OFDM symbol in the received and transmitted signals, respectively. m,n H(m,n) represents the channel state information, and T b τ is the sampling interval, τ is the time delay, and f is the sampling interval. d It is the Doppler frequency shift, ω n It is Gaussian white noise.

[0110] Figure 1 The figure shows a schematic diagram of the two-dimensional FFT signal processing flow. The flow of the signal processing method based on two-dimensional FFT is also shown in the figure.

[0111] The receiving end samples the received signal to obtain the received signal matrix D. R It is related to the transmitted signal matrix D T The relationship can be represented as

[0112] D R (m,n)=D T (m,n)exp(j2πnΔf(mT b -τ))exp(j2πf d mT b )+ω n .

[0113] By dividing the received signal matrix and the transmitted signal matrix bit-by-bit to eliminate the known phase shift of the nth subcarrier, the channel information matrix D containing the sensing information can be obtained. channel The element in the m-th row and n-th column can be represented as:

[0114]

[0115] For channel information matrix a g By applying the two-dimensional FFT algorithm, the time delay and Doppler values ​​can be estimated, and the distance and velocity of the target can be calculated.

[0116] The following section explains the algorithms related to loops.

[0117] The cyclic correlation algorithm first processes the transmitted and received signals with a time interval T. b Sampling is performed for the sampling interval, with N samples per OFDM symbol. a Next, discard the first N elements that serve as the cycle prefix. CP If there are N points, and only the last N points are retained, then the received signal can be written in the following form:

[0118] y m [n] = hsm [n-ε]exp[j2πnf d T b ], n=0,1,...,MN.

[0119] Among them, h channel attenuation, The delay is an integer multiple of the sampling interval, and M is the number of OFDM symbols involved in the sampling. Assuming the received and transmitted signals are cyclically correlated, it can be written as:

[0120]

[0121] y m Substituting the values, the above equation can be rewritten as:

[0122]

[0123] When n = ε, the correlation function reaches its peak, and we can obtain τ = nT. b .

[0124] Based on μ(n,m), the maximum likelihood estimation expression can be constructed as follows:

[0125]

[0126] Substituting the result obtained from the previous step through cyclic correlation search, and simplifying the above equation when the correlation function μ(n,m) reaches its peak, a two-dimensional channel information matrix can be obtained. Performing a DFT on the column vectors of this matrix and searching for peaks yields an estimate of the Doppler effect, from which the target velocity can be calculated. For details, see: Y. Zeng, Y. Ma and S. Sun, "Joint Radar-Communication With Cyclic Prefixed Single Carrier Waveforms," ​​in IEEE Transactions on Vehicular Technology, vol.69, no.4, pp.4069-4079, April 2020, doi:10.1109 / TVT.2020.2975243. (Y. Zeng, Y. Ma and S. Sun, "Joint Radar-Communication With Cyclic Prefixed Single Carrier Waveforms," ​​in IEEE Transactions on Vehicular Technology, Vol.69, No.4, pp.4069-4079, April 2020, doi:10.1109 / TVT.2020.2975243.) doi:10.1109 / TVT. 2020.2975243.).

[0127] Since the subcarriers are unused at the transmitting end, the frequency band corresponding to the unused subcarriers does not contain any information during transmission. At the receiving end, due to noise and interference, the unused subcarrier portion can still receive useless information, which mainly comes from noise and interference. Assume the set of unused subcarriers is Ω. empty Existing NC-OFDM signal processing schemes do not filter out subcarrier sets Ω empty Instead of processing the noise information, the signal is treated as a useful signal and used in radar signal processing. In this case, since the transmitter is idle, the following situation will occur when constructing the channel information matrix.

[0128]

[0129] The channel information matrix may contain elements with amplitudes far exceeding those of other items. When performing a two-dimensional FFT algorithm to obtain the peak index, it is impossible to obtain an accurate peak index, i.e., it is impossible to estimate the correct distance.

[0130] Because some subcarriers are idle, these subcarriers do not contain channel information at the receiver, and therefore cannot be used for velocity estimation. Traditional two-dimensional FFT algorithms use all subcarriers for velocity estimation, but in "spectral hole" scenarios, idle subcarriers need to be avoided.

[0131] The two-dimensional FFT scheme performs a Direct Fourier Transform (DFT) on each row of the channel information matrix, and then calculates an Indirect Fourier Transform (IDFT) on each column of the resulting matrix. The resulting matrix directly represents the range and Doppler two-dimensional radar image. Since a coherent deterministic process is added to the signal in each Fourier transform, a power gain of M*N times is generated. Due to the presence of vacant subcarriers, the column vectors are no longer linearly phase-shifted, and it is no longer possible to perform an IDFT on all row vectors. Therefore, the power gain in the two-dimensional FFT scheme is destroyed, requiring a new scheme to obtain the power gain.

[0132] Cyclic correlation (CCR) algorithms require the integrated signal to have good autocorrelation. Due to the presence of unused subcarriers, OFDM integrated signals cannot guarantee good autocorrelation, and may even exhibit high sidelobes that overwhelm the true autocorrelation main lobe. Furthermore, CCR algorithms use an exhaustive method to enumerate all possible cyclic shifts, making the algorithm computationally more complex.

[0133] In recent years, NC-OFDM signals have attracted widespread attention from academia and industry due to their excellent performance in frequency-selective channels and high efficiency in improving spectral efficiency. In congested electromagnetic environments, high-priority users are allocated spectrum resources preferentially, while low-priority users can only use fragmented idle frequency bands for data transmission. Therefore, for low-priority users, achieving integrated communication and sensing using discontinuous frequency bands presents greater challenges. In discontinuous spectrum scenarios with fragmented spectrum resources, traditional radar signal processing algorithms based on OFDM integrated waveform design have performance defects. The technical solution provided in this invention aims to improve existing radar signal processing algorithms and design radar processing algorithms suitable for NC-OFDM integrated waveforms.

[0134] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0135] Figure 2 The figure shows a schematic diagram of the implementation process of the integrated signal processing method, which may include:

[0136] Step 201: Obtain the spectrum decision sequence when modulating the NC-OFDM communication sensing integrated signal;

[0137] Step 202: Determine the vacant subcarriers based on the spectrum decision sequence;

[0138] Step 203: Perform two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers to obtain the target's distance and velocity.

[0139] In practice, the spectrum decision sequence is obtained based on spectrum sensing.

[0140] In practice, the integrated signal undergoes two-dimensional FFT signal processing based on the determined vacant subcarriers, including one or a combination of the following processes:

[0141] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0142] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0143] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0144] This scheme is based on the research background of integrated communication and sensing technology. It studies the design of radar signal processing algorithm for NC-OFDM integrated signal in non-continuous spectrum scenarios. Traditional radar signal processing algorithm based on OFDM integrated waveform design has performance defects when applied to NC-OFDM scenarios.

[0145] To improve existing radar signal processing algorithms, a radar processing algorithm suitable for NC-OFDM integrated waveforms is designed. Spectrum decision, energy aggregation, and carrier selection modules are introduced into the existing two-dimensional FFT signal processing technology. The channel information matrix is ​​constructed through spectrum decision, and energy aggregation and carrier selection are introduced to perform performance compensation for the ranging and velocity measurement processes, thereby improving the accuracy of ranging and velocity measurement.

[0146] The NC-OFDM integrated communication and sensing signal obtains a spectrum decision sequence based on spectrum sensing during modulation. Unlike existing NC-OFDM integrated communication and sensing systems, this sequence is used not only to assist in the generation of the integrated signal but also to assist in the radar signal processing process. The spectrum decision sequence assists radar signal processing in the following three steps.

[0147] Spectrum decision: When constructing the channel information matrix, the vacant subcarriers are located by the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are manually set to 0. This process is used to combat the effects of noise and interference.

[0148] Energy aggregation: When ranging using the column vectors of the channel information matrix, the number of OFDM symbols requiring energy aggregation is determined based on the number of vacant subcarriers reflected in the spectrum decision sequence. Energy aggregation of multiple symbols increases the energy of the channel information terms and reduces the impact of noise on the ranging results.

[0149] Carrier selection: Unused subcarriers cannot be used for ranging and velocity measurement because they do not contain channel information. Appropriate subcarriers need to be selected for velocity estimation based on the spectrum decision sequence.

[0150] The following examples will illustrate this further.

[0151] In implementation, when constructing the channel information matrix, vacant subcarriers are located using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0, including:

[0152] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0153] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0154] Specifically, in current communication systems, for environments with congested spectrum, the subcarriers corresponding to the vacant congested frequency bands are generally selected, and only other subcarriers are used. This type of OFDM system using discontinuous frequency bands is called an NC-OFDM system. An integrated system based on NC-OFDM first obtains a spectrum decision sequence based on spectrum sensing:

[0155] A = [a 0, a 1, ,...,a N-1, ],

[0156] Where N is the number of subcarriers, a n =0,1. When transmitting the integrated signal, the spectral decision sequence A is inserted as signaling into the preamble of the signal. The modulation symbol after constellation mapping, according to a... n The value of determines whether to modulate to a n On the corresponding subcarrier, when a n When a is 0, the subcarrier is unused; when a... n When the value is 1, the subcarrier carries the modulation symbol. Therefore, the transmitted signal can be written as:

[0157]

[0158] Among them, in a n =0 position, d m,n Setting it to 0 means it contains no information.

[0159] At the receiving end, the usage status of the subcarrier is first obtained based on the signaling, and then radar signal processing is performed. Figure 3 The diagram illustrates signal processing for spectral holes. The radar signal processing algorithm suitable for NC-OFDM waveforms is also shown in the figure, and its main components are as follows:

[0160] In practice, when using the column vectors of the channel information matrix for ranging, and determining the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence, after constructing the channel information matrix, the column vectors are used for energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0161] In practice, when selecting subcarriers for velocity estimation based on the vacant subcarriers reflected by the spectrum decision sequence, row vectors are used for carrier screening to obtain row vectors carrying channel information. DFT is then performed on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity.

[0162] Specifically, firstly, a received modulation symbol matrix and a transmitted modulation symbol matrix are constructed based on the transmitted and received signals. Before constructing the channel information matrix by dividing the two matrices, a spectrum decision is performed according to the designed signaling to determine the usage status of the subcarriers. This decision process identifies the vacant subcarriers Ω in the channel information matrix. empty Some columns are set to 0, while the rest contain valid channel state information. After constructing the channel information matrix, energy aggregation is performed on the column vectors. Then, an IDFT (Inverse Discrete Fourier Transform) is performed on the updated column vectors to obtain the peak index corresponding to the time delay. Carrier filtering is performed on the row vectors to obtain the row vectors carrying channel information, i.e., the updated row vectors. A DFT (Discrete Fourier Transform) is performed on the updated row vectors to obtain the peak index corresponding to the Doppler shift. The target's range and velocity are estimated based on the time delay and the Doppler peak index.

[0163] Implementation of the spectrum decision process:

[0164] The purpose of the spectrum decision process is to determine the received modulation symbol matrix D based on the designed signaling. R (m,n) and the transmitted modulation symbol matrix D T The empty subcarrier set Ω in (m,n) empty D T In (m,n), this part of the elements is set to 0, while D R The elements in the corresponding part of (m,n) are not zero due to the presence of noise. However, these elements do not contain channel information and will only interfere with the estimation of target distance in signal processing. Therefore, a spectrum decision process is needed to convert D... channel Set the corresponding element in the table to 0 to remove noise interference. Figure 4 The diagram illustrates the spectrum decision process, which may include:

[0165] First, let's start with D. R and D T Let D be the element in the nth row and mth column of the given data. R (m,n) and D T (m,n), using the spectral decision sequence A carried in the signaling as the decision condition, if a nA value of 0 indicates that the nth subcarrier is empty and contains no useful information. This subcarrier also does not carry channel information at the receiver. Therefore, the element in the nth row and mth column of the channel information matrix is ​​set to 0. If a n A value of 1 indicates that the nth subcarrier carries communication information. The subcarrier at the receiving end contains not only communication information but also channel information. In this case, the communication information in the received symbol is removed, and only the channel information is retained and stored in the channel information matrix D. channel In this context, it is used to estimate distance and speed.

[0166] Implementation of the energy aggregation process:

[0167] In implementation, after constructing the channel information matrix, energy aggregation is performed on the column vectors, and then IDFT is performed using the updated column vectors to obtain the peak index corresponding to the time delay, including:

[0168] Input channel information matrix;

[0169] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0170] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0171] Sum the IDFT results of the ranging vectors;

[0172] After performing a peak search, output the peak index.

[0173] Specifically, Figure 5 The diagram illustrates the energy aggregation process. The specific implementation is shown in the figure. After adding the spectrum decision process, some row vectors in the channel information matrix M are all-zero vectors. When performing IDFT on the column vectors, some terms are also zero. This is illustrated in the following equation:

[0174]

[0175] Due to the empty subcarrier set Ω empty The existence of allows the linear phase shift related to time delay to be written as:

[0176]

[0177] After performing IDFT, the resulting peak search sequence can be written in the following form:

[0178]

[0179] The generated peak may be submerged by noise, so channel information from multiple OFDM symbols needs to be superimposed to aggregate the channel information energy on each effective subcarrier. This improves the energy of the peak generated after IDFT and prevents the peak from being submerged by noise.

[0180] In NC-OFDM, the number of unloaded subcarriers is a crucial factor affecting the ranging performance of the integrated signal. The more unloaded subcarriers, the weaker the noise immunity of the integrated signal. This is because, during IDFT, the element k containing distance information... R The less (n) the peak energy The lower the value, the lower the energy of the noise. The number of unused subcarriers remains constant. Therefore, as the number of unused subcarriers increases, more OFDM symbols are needed for energy aggregation. By increasing the resources involved in signal processing, the peak search sequences obtained from IDFT of multiple OFDM symbols are jointly processed to improve the noise immunity of integrated signal ranging.

[0181] Therefore, multiple OFDM symbols need to be used for energy aggregation to reduce the impact of noise on the ranging results.

[0182]

[0183] When using M e After energy aggregation of OFDM symbols, the energy of multiple peak search sequences is superimposed, which increases the amplitude of the peaks without increasing the interference from noise. Therefore, it can counteract the effects of noise and improve the accuracy of peak index search.

[0184] Let the peak index obtained by peak search be k. r The distance to the target can be calculated based on the peak index:

[0185]

[0186] Carrier selection process implementation:

[0187] In implementation, row vectors are used for carrier filtering to obtain row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0188] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0189] Channel information for speed measurement is carried on non-empty subcarriers;

[0190] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0191] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0192] Specifically, Figure 6 The diagram illustrates the carrier selection process. The carrier selection process ensures that row vectors carrying channel information are used for velocity estimation, rather than using unused subcarriers. Since unused subcarriers are fixed, there are subcarriers where all symbols carry channel information. When performing the DFT, channel information from all symbols can be used for velocity estimation, thus eliminating the need for an energy aggregation process similar to ranging.

[0193] Based on the signaling designed in the spectrum decision process, the subcarriers used for velocity estimation can be obtained, and then velocity estimation can be achieved based on the available subcarriers.

[0194] The row vector formed by the linear phase shift of Doppler is obtained from the velocity measurement matrix. This row vector can be written as:

[0195]

[0196] Among them, f c It is the carrier frequency, T sym This represents the OFDM symbol duration, and c is the speed of light. Perform a DFT and search for peak indices.

[0197]

[0198] Let the peak index obtained by peak search be l. d The distance to the target can be calculated based on the peak index:

[0199]

[0200] Based on the same inventive concept, this invention also provides an integrated signal processing device and a computer-readable storage medium. Since the principle of these devices in solving problems is similar to that of the integrated signal processing method, the implementation of these devices can be referred to the implementation of the method, and repeated details will not be repeated.

[0201] When implementing the technical solutions provided in the embodiments of the present invention, they can be implemented in the following manner.

[0202] Figure 7 The figure shows a schematic diagram of an integrated signal processing device, which includes:

[0203] Processor 700 is used to read the program from memory 720 and execute the following procedures:

[0204] Acquire the spectrum decision sequence when modulating the integrated sensing signal of NC-OFDM communication;

[0205] The vacant subcarriers are determined based on the spectrum decision sequence;

[0206] The distance and velocity of the target are obtained by performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers;

[0207] Transceiver 710 is used to receive and send data under the control of processor 700.

[0208] In practice, the spectrum decision sequence is obtained based on spectrum sensing.

[0209] In practice, the integrated signal undergoes two-dimensional FFT signal processing based on the determined vacant subcarriers, including one or a combination of the following processes:

[0210] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0211] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0212] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0213] In implementation, when constructing the channel information matrix, vacant subcarriers are located using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0, including:

[0214] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0215] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0216] In practice, when using the column vectors of the channel information matrix for ranging, and determining the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence, after constructing the channel information matrix, the column vectors are used for energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0217] In implementation, after constructing the channel information matrix, energy aggregation is performed on the column vectors, and then IDFT is performed using the updated column vectors to obtain the peak index corresponding to the time delay, including:

[0218] Input channel information matrix;

[0219] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0220] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0221] Sum the IDFT results of the ranging vectors;

[0222] After performing a peak search, output the peak index.

[0223] In practice, when selecting subcarriers for velocity estimation based on the vacant subcarriers reflected by the spectrum decision sequence, row vectors are used for carrier screening to obtain row vectors carrying channel information. DFT is then performed on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity.

[0224] In implementation, row vectors are used for carrier filtering to obtain row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0225] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0226] Channel information for speed measurement is carried on non-empty subcarriers;

[0227] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0228] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0229] Among them, Figure 7 In this context, the bus architecture can include any number of interconnected buses and bridges, specifically linking various circuits together, represented by one or more processors (processor 700) and memory (memory 720). The bus architecture can also link various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. The transceiver 710 can be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over a transmission medium. The processor 700 is responsible for managing the bus architecture and general processing, and the memory 720 can store data used by the processor 700 during operation.

[0230] This invention also provides an integrated signal processing device, comprising:

[0231] The sequence module is used to acquire the spectrum decision sequence when modulating the NC-OFDM communication sensing integrated signal;

[0232] The subcarrier module is used to determine the vacant subcarriers based on the spectrum decision sequence;

[0233] The processing module is used to perform two-dimensional FFT signal processing on the integrated signal based on the determined idle subcarriers to obtain the target's distance and velocity.

[0234] In practice, the sequence module is further used to obtain a spectrum decision sequence based on spectrum sensing.

[0235] In implementation, the processing module is further configured to perform one or a combination of the following processes when performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers:

[0236] When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0.

[0237] When using the column vectors of the channel information matrix for ranging, the number of OFDM symbols that need to be energy-aggregated is determined based on the number of vacant subcarriers reflected by the spectrum decision sequence.

[0238] Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using the vacant subcarriers.

[0239] In implementation, the processing module is further used to locate vacant subcarriers through the spectrum decision sequence when constructing the channel information matrix, and to set the symbols carried on the corresponding subcarriers to 0, including:

[0240] When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal;

[0241] The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

[0242] In practice, the processing module is further used to determine the number of OFDM symbols that need energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence when ranging using the column vectors of the channel information matrix. After constructing the channel information matrix, the column vectors are used to perform energy aggregation, and the updated column vectors are used to perform IDFT to obtain the peak index corresponding to the time delay.

[0243] In implementation, the processing module is further used to, after constructing the channel information matrix, perform energy aggregation on the column vectors, and then use the updated column vectors to perform IDFT to obtain the peak index corresponding to the time delay, including:

[0244] Input channel information matrix;

[0245] The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers;

[0246] Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector;

[0247] Sum the IDFT results of the ranging vectors;

[0248] After performing a peak search, output the peak index.

[0249] In practice, the processing module is further used to perform carrier filtering by taking row vectors when selecting subcarriers for velocity estimation based on the empty subcarriers reflected by the spectrum decision sequence, to obtain row vectors carrying channel information, and to perform DFT on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and estimate the velocity.

[0250] In implementation, the processing module is further used to extract row vectors for carrier filtering, obtaining row vectors carrying channel information. A DFT is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including:

[0251] Non-empty subcarriers are determined based on the spectrum decision sequence;

[0252] Channel information for speed measurement is carried on non-empty subcarriers;

[0253] A velocity measurement matrix is ​​constructed using the channel information of the subcarriers;

[0254] Doppler shift and velocity are estimated based on the velocity measurement matrix.

[0255] For ease of description, the various parts of the device described above are divided into modules or units according to their functions. Of course, in implementing this invention, the functions of each module or unit can be implemented in one or more software or hardware components.

[0256] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned integrated signal processing method.

[0257] For specific implementation details, please refer to the implementation of the integrated signal processing method.

[0258] In summary, the technical solution provided by the embodiments of the present invention proposes a process for designing signaling based on a spectrum decision sequence; actively eliminating noise interference on unloaded carriers using the designed signaling when constructing the channel information matrix; selecting the number of NC-OFDM symbols for energy aggregation and realizing energy aggregation using the designed signaling during distance estimation; and selecting subcarriers containing channel information using the designed signaling during velocity estimation.

[0259] In NC-OFDM integrated communication and sensing signal processing in discontinuous spectrum scenarios, distance and velocity estimation of targets was achieved even when some subcarriers were idle, improving sensing efficiency and accuracy. In discontinuous spectrum scenarios, useful frequency band subcarriers were extracted, reducing noise interference to target sensing. Energy aggregation design improved the accuracy of distance estimation and enhanced noise and interference immunity. This facilitates the realization of integrated communication and sensing systems in congested spectrum environments.

[0260] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0261] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0262] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0263] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0264] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. An integrated signal processing method, characterized in that, include: Acquiring a spectrum decision sequence when modulating a non-continuous orthogonal frequency division multiplexing (NC-OFDM) communication sensing integrated signal; The vacant subcarriers are determined based on the spectrum decision sequence; The distance and velocity of the target are obtained by performing a two-dimensional fast Fourier transform (FFT) signal processing on the integrated signal based on the determined vacant subcarriers. Two-dimensional FFT signal processing is performed on the integrated signal based on the determined vacant subcarriers, including: When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0. When using the column vectors of the channel information matrix for ranging, the number of orthogonal frequency division multiplexing (OFDM) symbols that need energy aggregation is determined based on the number of vacant subcarriers reflected in the spectrum decision sequence. Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using an empty subcarrier.

2. The method as described in claim 1, characterized in that, The spectral decision sequence is obtained based on spectral sensing.

3. The method as described in claim 1, characterized in that, When constructing the channel information matrix, vacant subcarriers are located using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0, including: When transmitting the integrated signal, a spectrum decision sequence consisting of 0 or 1 is inserted as signaling into the preamble of the integrated signal; The modulation symbol after constellation mapping is modulated onto the subcarrier corresponding to the symbol based on the value of the symbol in the spectrum decision sequence. When the value of the symbol is 0, the subcarrier is unused, and when the value of the symbol is 1, the subcarrier carries the modulation symbol.

4. The method as described in claim 1, characterized in that, When using the column vectors of the channel information matrix for ranging, and determining the number of OFDM symbols requiring energy aggregation based on the number of vacant subcarriers reflected by the spectrum decision sequence, after constructing the channel information matrix, the column vectors are used for energy aggregation, and the updated column vectors are used to perform inverse discrete Fourier transform (IDFT) to obtain the peak index corresponding to the time delay.

5. The method as described in claim 4, characterized in that, After constructing the channel information matrix, energy aggregation is performed on the column vectors, and then IDFT is performed on the updated column vectors to obtain the peak index corresponding to the time delay, including: Input channel information matrix; The number of OFDM symbols required for energy aggregation is determined based on the number of vacant subcarriers; Extract the ranging vector corresponding to the number of OFDM symbols required for energy aggregation and perform IDFT on the ranging vector; Sum the IDFT results of the ranging vectors; After performing a peak search, output the peak index.

6. The method as described in claim 1, characterized in that, When selecting subcarriers for velocity estimation based on the vacant subcarriers responding to the spectral decision sequence, row vectors are used for carrier screening to obtain row vectors carrying channel information. DFT is then performed on the row vectors carrying channel information to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity.

7. The method as described in claim 6, characterized in that, Carrier filtering is performed on row vectors to obtain row vectors carrying channel information. A Discrete Fourier Transform (DFT) is then performed on these row vectors to obtain the peak index corresponding to the Doppler frequency shift and to estimate the velocity, including: Non-empty subcarriers are determined based on the spectrum decision sequence; Channel information for speed measurement is carried on non-empty subcarriers; A velocity measurement matrix is ​​constructed using the channel information of the subcarriers; Doppler shift and velocity are estimated based on the velocity measurement matrix.

8. An integrated signal processing device, characterized in that, include: The processor is used to read programs from memory and execute the following procedures: Acquire the spectrum decision sequence when modulating the integrated sensing signal of NC-OFDM communication; The vacant subcarriers are determined based on the spectrum decision sequence; The distance and velocity of the target are obtained by performing two-dimensional FFT signal processing on the integrated signal based on the determined vacant subcarriers; A transceiver is used to receive and send data under the control of a processor; Two-dimensional FFT signal processing is performed on the integrated signal based on the determined vacant subcarriers, including: When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0. When using the column vectors of the channel information matrix for ranging, the number of orthogonal frequency division multiplexing (OFDM) symbols that need energy aggregation is determined based on the number of vacant subcarriers reflected in the spectrum decision sequence. Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using an empty subcarrier.

9. An integrated signal processing device, characterized in that, include: The sequence module is used to acquire the spectrum decision sequence when modulating the NC-OFDM communication sensing integrated signal; The subcarrier module is used to determine the vacant subcarriers based on the spectrum decision sequence; The processing module is used to perform two-dimensional FFT signal processing on the integrated signal based on the determined idle subcarriers to obtain the target's distance and velocity; Two-dimensional FFT signal processing is performed on the integrated signal based on the determined vacant subcarriers, including: When constructing the channel information matrix, vacant subcarriers are located by using the spectrum decision sequence, and the symbols carried on the corresponding subcarriers are set to 0. When using the column vectors of the channel information matrix for ranging, the number of orthogonal frequency division multiplexing (OFDM) symbols that need energy aggregation is determined based on the number of vacant subcarriers reflected in the spectrum decision sequence. Based on the spectral decision sequence, a subcarrier is selected for velocity estimation using an empty subcarrier.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method of any one of claims 1 to 7.

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