Sensing method, communication device, and computer-readable storage medium

Abstract

The application provides a sensing method, a communication device and a computer readable storage medium. The sensing method comprises: obtaining a transmitting signal and an echo signal of the transmitting signal; constructing a channel information matrix according to the transmitting signal and the echo signal, the channel information matrix comprising a pilot part and a data part; performing two-dimensional Fourier transform on the pilot part to obtain a sensing result; judging whether the sensing result meets a sensing resolution requirement; if the sensing result does not meet the sensing resolution requirement, performing phase compensation on the channel information matrix according to the sensing result; performing two-dimensional Fourier transform on the pilot part and / or the data part in the compensated channel information matrix to obtain an updated sensing result, and returning to the step of judging whether the sensing result meets the sensing resolution requirement until the updated sensing result meets the sensing resolution requirement, and obtaining a final sensing result. The application can improve the sensing accuracy of the estimated sensing result.

Description

Technical Field

[0001] The present invention relates to the field of integrated sensing and communication technology, and in particular to a sensing method, a communication device and a computer-readable storage medium. Background Technology

[0002] With the rapid development of 5G Advance (5G-A) and 6G (6G) mobile communication systems, many intelligent applications and services have emerged, such as machine-type communication (MTC), connected robots and autonomous systems, brain-computer interfaces, and extended reality (XR). Existing mobile communication systems, composed of independent sensing and communication devices, cannot fully meet the demands of emerging services and technologies for simultaneous high data transmission and high-precision sensing. This is because individual sensing and communication devices interfere with each other. Furthermore, increasingly scarce spectrum resources cannot meet the spectrum needs of different devices.

[0003] Sensor-Communication Integration (JSC) technology has garnered widespread attention from academia and industry due to its advantages such as high spectrum utilization and low hardware cost. JSC technology reduces interference between sensing and communication and is expected to be used in intelligent applications requiring high communication rates and high-precision sensing capabilities, such as machine-type communication and extended reality in 5G-A and 6G.

[0004] However, in high-precision sensing scenarios, existing sensing schemes cannot provide high-precision sensing performance with low complexity. Summary of the Invention

[0005] This invention provides a sensing method, a communication device, and a computer-readable storage medium to address the problem of how to improve the sensing accuracy of sensing results.

[0006] To solve the above-mentioned technical problems, the present invention is implemented as follows:

[0007] In a first aspect, embodiments of the present invention provide a sensing method, including:

[0008] Acquire the transmitted signal and the echo signal of the transmitted signal;

[0009] A channel information matrix is ​​constructed based on the transmitted signal and the echo signal, the channel information matrix including a pilot part and a data part;

[0010] The sensing result is obtained by performing a two-dimensional Fourier transform on the pilot section;

[0011] Determine whether the perception result meets the perception resolution requirements;

[0012] If the sensing result does not meet the sensing resolution requirement, phase compensation is performed on the channel information matrix based on the sensing result;

[0013] A two-dimensional Fourier transform is performed on the pilot portion and / or data portion of the compensated channel information matrix to obtain an updated sensing result. The step of determining whether the sensing result meets the sensing resolution requirement is then performed until the updated sensing result meets the sensing resolution requirement, thus obtaining the final sensing result.

[0014] Optionally, constructing the channel information matrix based on the transmitted signal and the echo signal includes:

[0015] Construct a two-dimensional information matrix of the transmitted signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the transmitted signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol;

[0016] Construct a two-dimensional information matrix of the echo signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the echo signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol, and the communication information of the echo signal includes time delay information and Doppler information;

[0017] The channel information matrix is ​​obtained by dividing the two-dimensional information matrix of the transmitted signal and the two-dimensional information matrix of the echo signal by a dot.

[0018] Optionally, the step of performing a two-dimensional Fourier transform on the pilot portion to obtain the sensing result includes:

[0019] Perform an inverse discrete Fourier transform on the OFDM symbols of the pilot section to obtain the peak index related to the time delay;

[0020] Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset;

[0021] The estimated delay and sensing distance are calculated based on the peak index related to the delay, and the sensing results include the estimated delay and sensing distance;

[0022] The estimated value of the Doppler frequency offset and the sensing speed are calculated based on the peak index related to the Doppler frequency offset. The sensing results include the estimated value of the Doppler frequency offset and the sensing speed.

[0023] Optionally, the estimated time delay is calculated using the following formula:

[0024]

[0025] Where τ1 is the estimated delay obtained from the first estimation, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

[0026] Optionally, the estimated value of the Doppler frequency offset is calculated using the following formula:

[0027]

[0028] Among them, f d1 This is the estimated value of the Doppler frequency offset obtained from the first estimation. T is the peak index related to Doppler frequency offset obtained during the first estimation of sensing velocity. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0029] Optionally, the step of performing phase compensation on the channel information matrix based on the sensing result includes:

[0030] Phase compensation for the delay term is performed on the channel information matrix based on the estimated delay value;

[0031] Phase compensation is performed on each item in each row of the channel information matrix containing the pilot based on the estimated value of the Doppler frequency offset.

[0032] Optionally, the step of performing a two-dimensional Fourier transform on the pilot portion and / or data portion of the compensated channel information matrix to obtain the updated sensing result includes:

[0033] Perform a discrete inverse Fourier transform on the OFDM symbols of the pilot and / or data portions in the channel information matrix to obtain the peak index related to the time delay;

[0034] Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset;

[0035] The estimated latency and sensing distance are calculated based on the peak index related to latency.

[0036] The estimated value of Doppler frequency offset and sensing speed are calculated based on the peak index associated with Doppler frequency offset.

[0037] Optionally, the sensing distance can be represented in the following way:

[0038]

[0039] Where R is the sensing distance, c is the speed of light, and B is the bandwidth. Let X be the peak index related to time delay obtained when estimating the sensing distance for the αth time, and let N be the number of iterations used to calculate the sensing distance. pdenoted as , where is the number of subcarriers occupied by the pilot in the frequency domain, and N is the number of subcarriers in the frequency domain.

[0040] Optionally, the sensing speed is represented in the following manner:

[0041]

[0042] Where v is the final perceived speed, and c is the speed of light. Let f be the peak index related to Doppler frequency offset obtained during the α-th estimation of the sensing velocity, X be the number of iterations used to calculate the sensing velocity, and f be the peak index related to Doppler frequency offset. c T is the carrier frequency. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0043] In a second aspect, embodiments of the present invention provide a communication device, including:

[0044] An acquisition module is used to acquire the transmitted signal and the echo signal of the transmitted signal;

[0045] The construction module is used to construct a channel information matrix based on the transmitted signal and the echo signal, wherein the channel information matrix includes a pilot part and a data part;

[0046] The first processing module is used to perform a two-dimensional Fourier transform on the pilot section to obtain the sensing result;

[0047] The judgment module is used to determine whether the perception result meets the perception resolution requirements;

[0048] The phase compensation module is used to perform phase compensation on the channel information matrix based on the sensing results if the sensing results do not meet the sensing resolution requirements.

[0049] The second processing module is used to perform a two-dimensional Fourier transform on the pilot part and / or data part in the compensated channel information matrix to obtain an updated sensing result, and send the updated sensing result to the judgment module. The judgment module continues to execute the step of judging whether the sensing result meets the sensing resolution requirement until the updated sensing result meets the sensing resolution requirement, and obtains the final sensing result.

[0050] Thirdly, embodiments of the present invention provide a communication device, including: a processor, a memory, and a program stored in the memory and executable on the processor, wherein when the program is executed by the processor, it implements the steps of the sensing method described in the first aspect above.

[0051] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the sensing method described in the first aspect above.

[0052] In this embodiment of the invention, the pilot portion of the channel information matrix is ​​selected for the first sensing result estimation because the pilot signal has higher power and better correlation, resulting in better sensing performance. The first sensing result is then fed back into the channel information matrix as phase compensation. Based on the first sensing result, a smaller sensing range is defined, and the sensing result is estimated again. Through multiple iterations, a higher resolution sensing result can be obtained. Because the sensing accuracy is improved, a large amount of echo signal is not required, reducing computational load and increasing signal processing speed and refresh rate. Attached Figure Description

[0053] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0054] Figure 1 The frame structure of the OFDM-based integrated communication and sensing signal in this embodiment of the invention;

[0055] Figure 2 This is a flowchart illustrating the sensing method according to an embodiment of the present invention;

[0056] Figure 3 This is a schematic diagram of the sensing distance obtained after two iterations in an embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of the sensing speed obtained after two iterations in an embodiment of the present invention;

[0058] Figure 5 This is one of the structural schematic diagrams of a communication device according to an embodiment of the present invention;

[0059] Figure 6 This is a second schematic diagram of the communication device according to an embodiment of the present invention. Detailed Implementation

[0060] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0061] Orthogonal frequency division multiplexing (OFDM) technology is widely used in mobile communication systems and is the fundamental signal for integrated communication and sensing signal design. The integrated communication and sensing signal in the embodiments of this invention is an OFDM-based integrated communication and sensing signal. Please refer to... Figure 1 , Figure 1 The frame structure of the OFDM-based integrated communication and sensing signal in this embodiment of the invention is as follows: Figure 1 As can be seen, the frame structure of the integrated communication and sensing signal consists of pilot bits and data bits.

[0062] Please refer to Figure 2 This invention provides a sensing method applied to a communication device, which may be a base station or a user equipment (UE, also known as a terminal). The method includes:

[0063] Step 21: Acquire the transmitted signal and the echo signal of the transmitted signal;

[0064] The transmitted signal and the echo signal can be collectively referred to as the integrated communication and sensing signal.

[0065] In this embodiment of the invention, optionally, the transmitted signal s(t) can be represented in the following form:

[0066]

[0067] Where M is the number of OFDM symbols in a frame, N is the number of subcarriers in a frame, a(n,m) is the modulation symbol modulated on the subcarrier, and f n = nΔf, where Δf is the pilot subcarrier spacing, T sym The OFDM symbol duration is given by exp(), which is an exponential function with the natural constant e as the base, rect() is a rectangular window function, T is the T in the rect function, which means that rect is 1 during the time interval 0-T and 0 at other times, and j represents an imaginary number.

[0068] In this embodiment of the invention, optionally, the echo signal r(t) can be made by adding a time delay τ and a Doppler frequency shift f to the transmitted signal s(t). d express:

[0069]

[0070] Where h is the product of channel attenuation and radar cross section (RCS) coefficient.

[0071] Step 22: Construct a channel information matrix based on the transmitted signal and the echo signal. The channel information matrix includes a pilot part and a data part.

[0072] In this embodiment of the invention, a frame of OFDM-based integrated communication and sensing signal can be as follows: Figure 1 The diagram is divided into two parts: the reference signal in the pilot and the data bits. The transmitted signal in the pilot section can be represented as:

[0073]

[0074] Among them, M p N is the number of symbols occupied by the pilot portion in a frame. p a is the number of subcarriers occupied by the pilot portion in a frame. nm It is the modulation symbol carried on the pilot subcarrier, Δf p It is the pilot subcarrier spacing, T sym The duration of the OFDM symbol.

[0075] The transmitted signal in the data section can be represented as:

[0076]

[0077] Among them, M d N is the number of symbols used in the data portion of a frame. d d represents the number of subcarriers occupied by the data portion of a frame. mn The subcarriers in the data section carry modulation symbols, and Δf is the subcarrier spacing in the data section. There is a Δf interval between the subcarriers in the pilot section and the subcarriers in the data section. p =KΔf relationship.

[0078] The reflected signal can be expressed in the time domain as: s(t) = s p (t)+s d (t).

[0079] In this embodiment of the invention, optionally, the number of rows and columns of the channel information matrix correspond to the number of subcarriers and the number of symbols of the integrated communication sensing signal, respectively, and each element of the channel information matrix corresponds to a resource block of the integrated communication sensing signal.

[0080] Step 23: Perform a two-dimensional Fourier transform (2D FFT) on the pilot section to obtain the sensing result;

[0081] Step 24: Determine whether the perception result meets the perception resolution requirements;

[0082] Step 25: If the sensing result does not meet the sensing resolution requirement, perform phase compensation on the channel information matrix based on the sensing result;

[0083] Step 26: Perform a two-dimensional Fourier transform on the pilot portion and / or data portion of the compensated channel information matrix to obtain an updated sensing result, and continue to execute the step of determining whether the sensing result meets the sensing resolution requirement until the updated sensing result meets the sensing resolution requirement, and obtain the final sensing result.

[0084] Step 27: If the perception result meets the perception resolution requirement, then the perception result is taken as the final perception result.

[0085] In this embodiment of the invention, the pilot portion of the channel information matrix is ​​selected for the first sensing result estimation because the pilot signal has higher power and better correlation, resulting in better sensing performance. Then, the first sensing result is fed back into the channel information matrix as phase compensation. Based on the first sensing result, a smaller sensing range is defined, and the sensing result is estimated again. Through multiple iterations, a higher resolution sensing result can be obtained. Because the sensing accuracy is improved, a large amount of echo signal is not required, reducing computational load and increasing signal processing speed and refresh rate.

[0086] In this embodiment of the invention, if a two-dimensional Fourier transform is performed on the data portion of the channel information matrix during subsequent iterations, that is, the pilot and data are jointly sensed, all OFDM symbols within a frame of signal are fully utilized, and the resources in the signal frame structure are called more efficiently to realize the sensing function, thereby improving the sensing accuracy.

[0087] The sensing method of this invention can be applied to a scenario where a base station detects vehicles, integrating sensing and communication. In this scenario, the base station needs to be able to perceive the distribution of vehicles (terminals) in the surrounding environment in a timely and accurate manner and predict the movement status of vehicles based on the sensing results. By comprehensively managing and planning the movement status of each vehicle (terminal), the planning of vehicle (terminal) travel routes can be realized, improving the efficiency of the transportation network. For the scenario where a base station detects vehicles, the downlink signal transmitted by the base station includes pilot OFDM symbols and communication data OFDM symbols. After the base station transmits the downlink signal, the vehicle (terminal) can demodulate auxiliary communication data such as synchronization and phase compensation based on the pilot part. At the same time, an echo signal carrying sensing information such as the distance and speed of the vehicle (terminal) will be generated, and the base station can estimate the distance and speed of the vehicle (terminal) based on the received echo signal.

[0088] Of course, the sensing method of this invention can also be applied to other sensing scenarios, and this invention does not limit it.

[0089] In this embodiment of the invention, optionally, step 22 above, which involves constructing a channel information matrix based on the transmitted signal and the echo signal, includes:

[0090] Step 221: Construct a two-dimensional information matrix of the transmitted signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the transmitted signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol; wherein m and n are both integers greater than or equal to 1.

[0091] Step 222: Construct a two-dimensional information matrix of the echo signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the echo signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol, and the communication information of the echo signal includes time delay information and Doppler information;

[0092] Step 223: Divide the two-dimensional information matrix of the transmitted signal and the two-dimensional information matrix of the echo signal by a dot matrix to obtain the channel information matrix Y[n,m]. Let... and These are the column vector and row vector of Y[n,m], respectively, and the column vector and row vector contain time delay information and Doppler frequency shift information, respectively.

[0093] In this embodiment of the invention, optionally, in step 23 above, performing a two-dimensional Fourier transform on the pilot portion to obtain the sensing result includes:

[0094] Step 231: Perform inverse discrete Fourier transform on the OFDM symbols of the pilot section to obtain the peak index related to the time delay;

[0095] The discrete inverse Fourier transform is a type of two-dimensional Fourier transform.

[0096] Step 232: Perform Discrete Fourier Transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset;

[0097] The Discrete Fourier Transform is a type of Two-Dimensional Fourier Transform.

[0098] Step 233: Calculate the estimated value of the delay and the sensing distance based on the peak index related to the delay, wherein the sensing result includes the estimated value of the delay and the sensing distance;

[0099] Optionally, the sensing distance is calculated using the following formula:

[0100]

[0101] Where R1 is the sensing distance obtained in the first estimation, c is the speed of light, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

[0102] Optionally, the estimated time delay is calculated using the following formula:

[0103]

[0104] Where τ1 is the estimated delay obtained from the first estimation, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

[0105] In this embodiment of the invention, the first estimation of sensing distance refers to the first calculation of sensing distance using the pilot portion of the channel information matrix.

[0106] Step 234: Calculate the estimated value of Doppler frequency offset and the sensing speed based on the peak index related to Doppler frequency offset. The sensing results include the estimated value of Doppler frequency offset and the sensing speed.

[0107] Optionally, the sensing speed is calculated using the following formula:

[0108]

[0109] Where v1 is the perceived speed obtained in the first estimation, and c is the speed of light. f is the peak index related to Doppler frequency offset obtained during the first estimation of sensing velocity. c T is the carrier frequency. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0110] Optionally, the estimated value of the Doppler frequency offset is calculated using the following formula:

[0111]

[0112] Among them, f d1 This is the estimated value of the Doppler frequency offset obtained from the first estimation. T is the peak index related to Doppler frequency offset obtained during the first estimation of sensing velocity. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0113] In this embodiment of the invention, the first estimation of sensing speed refers to the first calculation of sensing speed using the pilot part of the channel information matrix.

[0114] By performing a two-dimensional Fourier transform on the pilot section for the first time, the ranging accuracy ΔR and the velocity accuracy Δv of the sensing distance are obtained as follows:

[0115]

[0116]

[0117] In this embodiment of the invention, optionally, step 25 above, wherein performing phase compensation on the channel information matrix based on the sensing result includes:

[0118] Step 251: Perform phase compensation on the delay term of the channel information matrix based on the estimated delay value;

[0119] Step 252: Perform phase compensation on each item in each row of the channel information matrix containing pilots based on the estimated value of the Doppler frequency offset.

[0120] In this embodiment of the invention, optionally, in step 26 above, performing a two-dimensional Fourier transform on the pilot portion and / or data portion of the compensated channel information matrix to obtain the updated sensing result includes:

[0121] Step 261: Perform inverse discrete Fourier transform on the OFDM symbols of the pilot and / or data parts in the channel information matrix to obtain the peak index related to the time delay;

[0122] Step 262: Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset;

[0123] Step 263: Calculate the estimated latency and sensing distance based on the latency-related peak index;

[0124] Step 264: Calculate the estimated value of Doppler frequency offset and sensing speed based on the peak index related to Doppler frequency offset.

[0125] In this embodiment of the invention, optionally, the sensing distance is represented in the following manner:

[0126]

[0127] Where R is the sensing distance, c is the speed of light, and B is the bandwidth. Let X be the peak index related to time delay obtained when estimating the sensing distance for the αth time, and let N be the number of iterations used to calculate the sensing distance. p denoted as , where is the number of subcarriers occupied by the pilot in the frequency domain, and N is the number of subcarriers in the frequency domain.

[0128] In this embodiment of the invention, optionally, the sensing speed is represented in the following manner:

[0129]

[0130] Where v is the perceived speed and c is the speed of light. Let f be the peak index related to Doppler frequency offset obtained during the α-th estimation of the sensing velocity, X be the number of iterations used to calculate the sensing velocity, and f be the peak index related to Doppler frequency offset. c T is the carrier frequency. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0131] The following describes in detail the estimation process of sensing distance and sensing speed based on the iterative approach.

[0132] 1) Perceptual distance estimation based on iterative thinking

[0133] The time delay τ can be written as τ = τ1 + τ2 + ... + τ X , where τ1,τ2,...,τ X These are the estimated time delays obtained in each iteration, and X represents the number of iterations.

[0134] The peak index related to latency obtained from the first estimation can be used to calculate τ1:

[0135]

[0136] Where τ1 is the estimated delay obtained from the first estimation, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

[0137] Phase compensation for the time delay term is performed on the channel information matrix Y[n,m] based on the τ1 obtained from the first estimation, where the m-th column vector in Y[n,m] is... After phase compensation, it is recorded as right Perform iterative estimation using the Inverse Discrete Fourier Transform (IDFT). This is done by searching the IDFT. The peak value can be used to obtain its peak index.

[0138] in, and They can be represented as follows:

[0139]

[0140]

[0141] Where, N d Δf is the number of subcarriers occupied by the data portion in a frame, and Δf is the subcarrier spacing of the data portion.

[0142] right The process of performing iterative estimation using IDFT is represented as follows:

[0143]

[0144] make The above formula can be simplified to:

[0145]

[0146] Analyzing the terms sinc(πΔτN) and exp(jπΔτ(N-1)) in the above equation, both terms reach their maximum values ​​when Δτ is 0. Therefore, when Δτ is 0, r(k d Therefore, by searching r(k) to obtain the maximum value. d The peak value of ) can be used to obtain its peak index. Satisfy the following formula:

[0147]

[0148] Where, N p N represents the number of subcarriers occupied by the pilot portion in a frame, where N is the total number of subcarriers in a frame.

[0149] according to The sensing distance of the target can be calculated as follows:

[0150]

[0151] It can be deduced that after X (X≥2) iterations, the estimated perceived distance can be expressed as:

[0152]

[0153] Where R is the sensing distance, c is the speed of light, and B is the bandwidth. Let X be the peak index related to time delay obtained when estimating the sensing distance for the αth time, and let N be the number of iterations used to calculate the sensing distance. p denoted as , where is the number of subcarriers occupied by the pilot in the frequency domain, and N is the number of subcarriers in the frequency domain.

[0154] After X iterations, the ranging accuracy can be improved to:

[0155]

[0156] 2) Perception speed estimation based on iterative thinking

[0157] The Doppler frequency shift f can be reduced d Let f d =f d1 +f d2 +...+f dX , where f d1 ,f d2 ,...,fdX These are the Doppler values ​​obtained from each iteration.

[0158] Based on the peak index related to Doppler frequency offset obtained from the first estimation, f can be calculated. d1 :

[0159]

[0160] For each item in each row of Y[n,m] containing pilot frequencies, phase compensation is performed based on the estimated value of the Doppler frequency offset from the first estimation. Let the nth row be written as:

[0161]

[0162] The result after phase compensation is:

[0163]

[0164] right Perform iterative estimation using the DFT (Discrete Fourier Transform):

[0165]

[0166] make The above formula can be simplified to

[0167]

[0168] For the above formula, sinc(πΔf) d M) and exp(jπΔf d Analyzing the two terms (M-1), when Δf d When Δf is 0, both terms reach their maximum values, therefore when Δf d When r(g) is 0, d Therefore, by searching r(g) to obtain the maximum value. d The peak value of ) can be used to obtain its peak index. Satisfy the following formula:

[0169]

[0170] according to The perception speed of the target can be calculated as follows:

[0171]

[0172] It can be deduced that after X (X≥2) iterations, the estimated value of the perception speed can be written as:

[0173]

[0174] After X iterations, the distance resolution is improved to:

[0175]

[0176] Please refer to Figure 3 and Figure 4 , Figure 3 and Figure 4 This demonstrates the improvement in ranging and velocity measurement accuracy after two iterations. Figure 3 and Figure 4 The horizontal axis represents the sequence number of the sensing result obtained after the two-dimensional Fourier transform, and the vertical axis represents the corresponding amplitude. Using 512 subcarriers, 14 OFDM symbols, and a subcarrier spacing of 15 kHz, a target moving at 15 m / s at a distance of 115 m was sensed. The sensing accuracy using existing methods is 19.53 m and 6.70 m / s. Using the sensing method of this invention, after two iterations, the sensing accuracy can be improved to 0.038 m and 0.478 m / s.

[0177] Please refer to Figure 5 This invention also provides a communication device 50, comprising:

[0178] Acquisition module 51 is used to acquire the transmitted signal and the echo signal of the transmitted signal;

[0179] Construction module 52 is used to construct a channel information matrix based on the transmitted signal and the echo signal, the channel information matrix including a pilot part and a data part;

[0180] The first processing module 53 is used to perform a two-dimensional Fourier transform on the pilot section to obtain the sensing result;

[0181] The judgment module 54 is used to determine whether the perception result meets the perception resolution requirements;

[0182] Phase compensation module 55 is used to perform phase compensation on the channel information matrix based on the perception result if the perception result does not meet the perception resolution requirement;

[0183] The second processing module 56 is used to perform a two-dimensional Fourier transform on the pilot part and / or data part in the compensated channel information matrix to obtain an updated sensing result, and send the updated sensing result to the judgment module 54. The judgment module 54 continues to execute the step of judging whether the sensing result meets the sensing resolution requirement until the updated sensing result meets the sensing resolution requirement, and obtains the final sensing result.

[0184] In this embodiment of the invention, the pilot portion of the channel information matrix is ​​selected for the first sensing result estimation because the pilot signal has higher power and better correlation, resulting in better sensing performance. The first sensing result is then fed back into the channel information matrix as phase compensation. Based on the first sensing result, a smaller sensing range is defined, and the sensing result is estimated again. Through multiple iterations, a higher resolution sensing result can be obtained. Because the sensing accuracy is improved, a large amount of echo signal is not required, reducing computational load and increasing signal processing speed and refresh rate.

[0185] Optionally, the construction module 52 is used to construct a two-dimensional information matrix of the transmitted signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the transmitted signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol; construct a two-dimensional information matrix of the echo signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the echo signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol, and the communication information of the echo signal includes time delay information and Doppler information; and divide the two-dimensional information matrix of the transmitted signal and the two-dimensional information matrix of the echo signal by a dot to obtain a channel information matrix.

[0186] Optionally, the first processing module 53 is configured to perform an inverse discrete Fourier transform on the OFDM symbols of the pilot section to obtain a peak index related to the time delay; calculate an estimated value of the time delay and a sensing distance based on the peak index related to the time delay, wherein the sensing result includes the estimated value of the time delay and the sensing distance; perform a discrete Fourier transform on the subcarriers containing the pilot in the channel information matrix to obtain a peak index related to the Doppler frequency offset; and calculate an estimated value of the Doppler frequency offset and a sensing speed based on the peak index related to the Doppler frequency offset, wherein the sensing result includes the estimated value of the Doppler frequency offset and the sensing speed.

[0187] Optionally, the estimated time delay is calculated using the following formula:

[0188]

[0189] Where τ1 is the estimated delay obtained from the first estimation, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

[0190] Optionally, the estimated value of the Doppler frequency offset is calculated using the following formula:

[0191]

[0192] Among them, f d1 This is the estimated value of the Doppler frequency offset obtained from the first estimation. T is the peak index related to Doppler frequency offset obtained during the first estimation of sensing velocity. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0193] Optionally, the phase compensation module 55 is used to perform phase compensation on the delay term of the channel information matrix according to the estimated delay value; and to perform phase compensation on each term of each row containing pilots in the channel information matrix according to the estimated Doppler frequency offset value.

[0194] Optionally, the second processing module 56 is configured to perform inverse discrete Fourier transform on the OFDM symbols of the pilot portion and / or data portion in the channel information matrix to obtain a peak index related to time delay; perform discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain a peak index related to Doppler frequency offset; calculate an estimated value of time delay and sensing distance based on the peak index related to time delay; and calculate an estimated value of Doppler frequency offset and sensing speed based on the peak index related to Doppler frequency offset.

[0195] Optionally, the sensing distance can be represented in the following way:

[0196]

[0197] Where R is the sensing distance, c is the speed of light, and B is the bandwidth. Let X be the peak index related to time delay obtained when estimating the sensing distance for the αth time, and let N be the number of iterations used to calculate the sensing distance. p denoted as , where is the number of subcarriers occupied by the pilot in the frequency domain, and N is the number of subcarriers in the frequency domain.

[0198] Optionally, the sensing speed is represented in the following manner:

[0199]

[0200] Where v is the final perceived speed, and c is the speed of light. Let f be the peak index related to Doppler frequency offset obtained during the α-th estimation of the sensing velocity, X be the number of iterations used to calculate the sensing velocity, and f be the peak index related to Doppler frequency offset. c T is the carrier frequency. sym M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

[0201] Please refer to Figure 6The present invention also provides a communication device 60, including a processor 61, a memory 62, and a computer program stored in the memory 62 and executable on the processor 61. When the computer program is executed by the processor 61, it implements the various processes of the above-described sensing method embodiments and achieves the same technical effect. To avoid repetition, it will not be described again here.

[0202] This invention also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the various processes of the above-described sensing method embodiments and achieves the same technical effects. To avoid repetition, it will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0203] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0204] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0205] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of the present invention.

Claims

1. A sensing method, characterized in that, include: Acquire the transmitted signal and the echo signal of the transmitted signal; A channel information matrix is ​​constructed based on the transmitted signal and the echo signal, the channel information matrix including a pilot part and a data part; The sensing result is obtained by performing a two-dimensional Fourier transform on the pilot section; Determine whether the perception result meets the perception resolution requirements; If the sensing result does not meet the sensing resolution requirement, phase compensation is performed on the channel information matrix based on the sensing result; A two-dimensional Fourier transform is performed on the pilot part and / or data part in the compensated channel information matrix to obtain an updated sensing result, and the process returns to the step of determining whether the sensing result meets the sensing resolution requirement, until the updated sensing result meets the sensing resolution requirement, and the final sensing result is obtained. The process of performing a two-dimensional Fourier transform on the pilot portion to obtain the sensing result includes: Perform an inverse discrete Fourier transform on the OFDM symbols of the pilot section to obtain the peak index related to the time delay; The estimated delay and sensing distance are calculated based on the peak index related to the delay, and the sensing results include the estimated delay and sensing distance; Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset; The estimated value of the Doppler frequency offset and the sensing speed are calculated based on the peak index related to the Doppler frequency offset. The sensing results include the estimated value of the Doppler frequency offset and the sensing speed.

2. The sensing method according to claim 1, characterized in that, The step of constructing the channel information matrix based on the transmitted signal and the echo signal includes: Construct a two-dimensional information matrix of the transmitted signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the transmitted signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol; Construct a two-dimensional information matrix of the echo signal, wherein the element in the nth row and mth column of the two-dimensional information matrix of the echo signal represents the communication information modulated on the nth subcarrier of the mth OFDM symbol, and the communication information of the echo signal includes time delay information and Doppler information; The channel information matrix is ​​obtained by dividing the two-dimensional information matrix of the transmitted signal and the two-dimensional information matrix of the echo signal by a dot.

3. The sensing method according to claim 1, characterized in that, The estimated time delay is calculated using the following formula: ； in, Here, B is the estimated delay obtained from the first estimation, and B is the bandwidth. This is the peak index related to latency obtained during the first estimation of the sensing distance.

4. The sensing method according to claim 1, characterized in that, The estimated value of the Doppler frequency offset is calculated using the following formula: ； in, This is the estimated value of the Doppler frequency offset obtained from the first estimation. This is the peak index related to Doppler frequency offset obtained during the first estimation of sensing velocity. M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

5. The sensing method according to claim 1, characterized in that, The step of performing phase compensation on the channel information matrix based on the sensing result includes: Phase compensation for the delay term is performed on the channel information matrix based on the estimated delay value; Phase compensation is performed on each item in each row of the channel information matrix containing the pilot based on the estimated value of the Doppler frequency offset.

6. The sensing method according to claim 1, characterized in that, The updated sensing results obtained by performing a two-dimensional Fourier transform on the pilot and / or data portions of the compensated channel information matrix include: Perform a discrete inverse Fourier transform on the OFDM symbols of the pilot and / or data portions in the channel information matrix to obtain the peak index related to the time delay; Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset; The estimated latency and the updated sensing distance are calculated based on the latency-related peak index. The estimated value of the Doppler frequency offset and the updated sensing speed are calculated based on the peak index associated with the Doppler frequency offset.

7. The sensing method according to claim 6, characterized in that, The updated sensing distance is represented as follows: ； in, The updated sensing distance is given by c, where c is the speed of light and B is the bandwidth. For the first The latency-related peak index is obtained when estimating the updated sensing distance, where X is the number of iterations used to calculate the updated sensing distance. denoted as , where is the number of subcarriers occupied by the pilot in the frequency domain, and N is the number of subcarriers in the frequency domain.

8. The sensing method according to claim 6, characterized in that, The updated sensing speed is represented as follows: ； in, The final perceived speed is given by c, where c is the speed of light. For the first The peak index related to Doppler frequency offset is obtained when estimating the updated sensing velocity, where X is the number of iterations used to calculate the updated sensing velocity. For carrier frequency, M represents the duration of an OFDM symbol, and M represents the number of OFDM symbols in a frame.

9. A communication device, characterized in that, include: An acquisition module is used to acquire the transmitted signal and the echo signal of the transmitted signal; The construction module is used to construct a channel information matrix based on the transmitted signal and the echo signal, wherein the channel information matrix includes a pilot part and a data part; The first processing module is used to perform a two-dimensional Fourier transform on the pilot section to obtain the sensing result; The judgment module is used to determine whether the perception result meets the perception resolution requirements; The phase compensation module is used to perform phase compensation on the channel information matrix based on the sensing results if the sensing results do not meet the sensing resolution requirements. The second processing module is used to perform a two-dimensional Fourier transform on the pilot part and / or data part in the compensated channel information matrix to obtain an updated sensing result, and send the updated sensing result to the judgment module, which then continues to execute the step of judging whether the sensing result meets the sensing resolution requirement until the updated sensing result meets the sensing resolution requirement, and obtains the final sensing result. The step of performing a two-dimensional Fourier transform on the pilot portion to obtain the sensing result includes: Perform an inverse discrete Fourier transform on the OFDM symbols of the pilot section to obtain the peak index related to the time delay; The estimated delay and sensing distance are calculated based on the peak index related to the delay, and the sensing results include the estimated delay and sensing distance; Perform a discrete Fourier transform on the subcarriers containing pilots in the channel information matrix to obtain the peak index related to the Doppler frequency offset; The estimated value of the Doppler frequency offset and the sensing speed are calculated based on the peak index related to the Doppler frequency offset. The sensing results include the estimated value of the Doppler frequency offset and the sensing speed.

10. A communication device, characterized in that, include: A processor, a memory, and a program stored in the memory and executable on the processor, wherein the program, when executed by the processor, implements the steps of the sensing method as described in any one of claims 1 to 8.

11. 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 steps of the sensing method as described in any one of claims 1 to 8.

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