Active-passive cooperative perception method and device

Abstract

The embodiment of the present application provides a kind of active and passive cooperative perception method and device, the method comprises: according to the frequency band of echo signal determines the first echo signal of active perception and the second echo signal of passive perception, eliminates the sending signal information in echo signal and obtains the target sensing information of active and passive perception, carries out relevant processing to the target sensing information of active and passive perception, eliminates the time-frequency error carried in the second echo signal, obtains the sensing information used for ranging and speed measurement of target object in passive perception.To realize the elimination of TO and CFO in passive perception, improve the sensing performance.

Description

Technical Field

[0001] This invention relates to the field of sensing technology, and in particular to a method and apparatus for active and passive collaborative sensing. Background Technology

[0002] In the field of perception technology, a sensing node can receive echo signals reflected by a target, use signal processing algorithms to extract phase change information containing target distance and velocity information from the echo signals, and estimate the target's distance and velocity information based on the phase change information, thereby realizing the perception of the target.

[0003] Based on the different sources of the echo signals, sensing can be specifically divided into active sensing and passive sensing. Active sensing refers to a sensing method where sensing nodes estimate parameters such as target distance and velocity by receiving their own echo signals reflected from the target. Passive sensing refers to a sensing method where sensing nodes detect targets by receiving echo signals emitted by other nodes that have been reflected from the target.

[0004] However, in passive sensing, the sensing nodes that transmit and receive signals, i.e., the transceiver ends, are spatially separated, making it difficult to guarantee strict time-frequency synchronization. This results in Time Offsets (TO) and Carrier Frequency Offsets (CFO) in passive sensing. TO and CFO cause random phase changes in the echo signal, affecting the receiver's ability to estimate target parameters based on these phase changes. Consequently, this leads to significant target parameter estimation errors and reduces sensing performance.

[0005] In communication systems, the issues of Time of Response (TO) and Time of Fundamental Response (CFO) also exist between the communicating parties. For time-frequency asynchrony between base stations and users, or between base stations themselves, GPS (Global Positioning System) or BeiDou system is preferred for clock synchronization when conditions permit. In the event of GPS failure, the transceiver can achieve time synchronization through information exchange based on the IEEE 1588.v2 protocol. However, while these synchronization methods can meet the synchronization requirements of communication systems, their synchronization accuracy is insufficient to meet the synchronization requirements of sensing systems.

[0006] In the field of traditional radar sensing, the targets are relatively large, and the accuracy requirements are not so high. Therefore, most of the sensing is based on GPS synchronization to achieve relatively coarse-precision sensing. For the synchronization problem of the transceiver end in the GPS denied scenario, communication interaction is mostly used to achieve coarse-precision synchronization, which is difficult to achieve high-precision sensing.

[0007] In the field of integrated sensing and communication, the use of communication signals to sense short-range, small targets places higher demands on the synchronization of passive sensing. Most existing active-passive collaborative sensing solutions do not consider the separation of transmission and reception at sensing nodes and the asynchronous nature of time and frequency, directly assuming that precise synchronization between the transmission and reception of sensing nodes can be achieved, which is difficult to meet the needs of practical application scenarios.

[0008] Therefore, for passive sensing scenarios with separate transmitting and receiving ends and asynchronous time and frequency, there is an urgent need to propose a sensing method to improve sensing performance. Summary of the Invention

[0009] The purpose of this invention is to provide a method for active-passive collaborative sensing, thereby eliminating TO and CFO in passive sensing and improving sensing performance. The specific technical solution is as follows:

[0010] In a first aspect, embodiments of the present invention provide an active-passive collaborative sensing method, applied to a first sensing node, the method comprising:

[0011] Receive the echo signal reflected by the target object;

[0012] Based on the frequency band of the echo signal, a first echo signal and a second echo signal are separated from the echo signal; wherein, the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node;

[0013] Based on the first echo modulation symbol and the first transmitted modulation symbol, the first target sensing information of active sensing is determined; wherein, the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal;

[0014] The second target sensing information is determined passively based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal.

[0015] Separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information;

[0016] The second time delay sensing information and the second frequency shift sensing information are separated from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift information includes carrier frequency deviation CFO;

[0017] The first time delay perception information and the second time delay perception information are processed to obtain time delay error perception information;

[0018] A delay error perception vector is constructed based on the first delay perception information and the delay error perception information. Correlation processing is performed on the second delay perception information and the delay error perception vector to obtain third delay perception information. Both the third delay perception information and the first delay perception information are used to obtain the distance information of the target object.

[0019] The first frequency shift sensing information and the second frequency shift sensing information are subjected to correlation processing to obtain frequency shift error sensing information;

[0020] A frequency shift error sensing vector is constructed based on the first frequency shift sensing information and the frequency shift error sensing information. Correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to obtain third frequency shift sensing information. Both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

[0021] Secondly, embodiments of the present invention provide an active-passive collaborative sensing device, applied to a first sensing node, comprising:

[0022] The receiving module is used to receive the echo signal reflected by the target object;

[0023] The first separation module is used to separate a first echo signal and a second echo signal from the echo signal according to the frequency band of the echo signal; wherein the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node.

[0024] The first determining module is used to determine the first target sensing information actively sensed based on the first echo modulation symbol and the first transmitted modulation symbol; wherein the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal;

[0025] The second determining module is used to determine the passively sensed second target sensing information based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal;

[0026] The second separation module is used to separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information;

[0027] The third separation module is used to separate the second time delay sensing information and the second frequency shift sensing information from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift information includes carrier frequency deviation CFO;

[0028] The first processing module is used to perform relevant processing on the first time delay perception information and the second time delay perception information to obtain time delay error perception information;

[0029] The second processing module is used to construct a delay error perception vector based on the first delay perception information and the delay error perception information, and to perform correlation processing on the second delay perception information and the delay error perception vector to obtain third delay perception information; both the third delay perception information and the first delay perception information are used to obtain the distance information of the target object;

[0030] The third processing module is used to perform relevant processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information;

[0031] The fourth processing module is used to construct a frequency shift error sensing vector based on the first frequency shift sensing information and the frequency shift error sensing information, and to perform correlation processing on the second frequency shift sensing information and the frequency shift error sensing vector to obtain third frequency shift sensing information; both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

[0032] Thirdly, embodiments of the present invention provide an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0033] Memory, used to store computer programs;

[0034] When a processor executes a program stored in memory, it implements any of the active-passive cooperative sensing methods described in the first aspect.

[0035] This invention also provides a computer program product containing instructions that, when run on a computer, causes the computer to execute any of the active-passive cooperative sensing methods described above.

[0036] Beneficial effects of the embodiments of the present invention:

[0037] The active-passive collaborative sensing method provided in this invention separates the first actively sensed echo signal and the second passively sensed echo signal from the echo signal according to the frequency band of the echo signal. Based on the echo signal and the sensing signal, it determines the first actively sensed target sensing information and the second passively sensed target sensing information. From the first target sensing information, it separates the first actively sensed time delay sensing information and the first frequency shift sensing information, and from the second target sensing information, it separates the second passively sensed time delay sensing information and the second frequency shift sensing information. This allows for separate processing of the time delay sensing information and frequency shift sensing information of the target object, simplifying the calculation. By performing correlation processing on the first and second time-delay sensing information, the time delay difference and TO in passive sensing are extracted, obtaining time delay error information and constructing a time delay error sensing vector. Then, correlation processing is performed on the second time-delay sensing information and the time delay error sensing vector to eliminate the time delay difference and TO from the second time-delay sensing information. Similarly, by performing correlation processing on the first and second frequency shift sensing information, the frequency shift difference and CFO in passive sensing are extracted, obtaining frequency shift error information and constructing a frequency shift error sensing vector. Then, correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to eliminate the frequency shift difference and CFO from the second frequency shift sensing information. By actively sensing to assist in eliminating the time delay difference, frequency shift difference, TO, and CFO in the target sensing information in passive sensing, the second echo signal is transformed from an interference signal into a useful signal, which can improve the signal-to-interference-plus-noise ratio of the echo signal received by the first sensing node, thereby improving sensing performance.

[0038] Furthermore, the active-passive collaborative sensing method provided in this embodiment of the invention achieves complete elimination of time delay difference, frequency shift difference, TO and CFO, without requiring further processing of time delay difference and frequency shift difference through geometric alignment, and has high processing efficiency.

[0039] Furthermore, the embodiments of the present invention are also applicable to scenarios where there are obstacles between the passive sensing transceivers, thus having a wide range of applications.

[0040] Of course, implementing any product or method of the present invention does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0041] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0042] Figure 1 This is an example diagram of a sensing scene provided in an embodiment of the present invention;

[0043] Figure 2 This is an example diagram of a vehicle traffic scenario provided in an embodiment of the present invention;

[0044] Figure 3 This is an example diagram of an industrial flexible manufacturing scenario provided in an embodiment of the present invention;

[0045] Figure 4 This is an example diagram illustrating the deviation between time delay and Doppler frequency shift in active and passive sensing provided in an embodiment of the present invention;

[0046] Figure 5 This is a flowchart illustrating the first embodiment of the active-passive collaborative sensing method provided in this invention.

[0047] Figure 6 This is a flowchart illustrating the second embodiment of the active-passive collaborative sensing method provided in this invention.

[0048] Figure 7 This is a schematic diagram of an active-passive collaborative sensing method provided in an embodiment of the present invention;

[0049] Figure 8 This is a schematic diagram of the active-passive collaborative sensing device provided in an embodiment of the present invention;

[0050] Figure 9 This is a schematic diagram of the structure of the electronic device provided in an embodiment of the present invention. Detailed Implementation

[0051] 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 embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art based on the present invention are within the scope of protection of the present invention.

[0052] To facilitate understanding, the following is an exemplary description of the perception scenarios involved in the active-passive collaborative perception method provided in the embodiments of the present invention.

[0053] The active-passive collaborative sensing method provided in this invention involves scenarios where multiple sensing nodes simultaneously sense a target, including active sensing and passive sensing.

[0054] Figure 1 This is an example diagram of a perception scene provided in an embodiment of the present invention. Specifically, it is an example of a perception scene that includes two perception nodes, perception node 1 and perception node 2, and a total of L targets, from target 1 to target L.

[0055] like Figure 1As shown, sensing node 1 and sensing node 2 simultaneously send sensing signals to the target. After the sensing signals reach the target and are reflected by the target, sensing node 1 can receive not only its own echo but also the echo sent by sensing node 2 to the target and reflected back. Specifically, Figure 1 The solid lines shown represent the sensing signals sent by the sensing nodes. Figure 1 The dashed line shown represents the echo received by sensing node 1.

[0056] Among them, sensing node 1 can perceive the target through its own echo, that is, active perception, or it can perceive the target through the echo reflected by the target sent by sensing node 2, that is, passive perception. Therefore, active and passive coordinated perception can be achieved at sensing node 1.

[0057] Furthermore, the active-passive collaborative sensing method provided in this embodiment of the invention does not require a Line-of-Sight (LOS) path to exist between sensing node 1 and sensing node 2, i.e., between the passive sensing transceiver ends. Therefore, this embodiment of the invention is applicable to sensing scenarios where there are no obstacles obstructing sensing node 1 and sensing node 2, i.e., a LOS path exists, and also applicable to sensing scenarios where there are obstacles obstructing sensing node 1 and sensing node 2, i.e., a LOS path does not exist.

[0058] Based on the aforementioned perception scenario, the active-passive collaborative perception method provided in this embodiment of the invention is specifically applied to a perception node that performs target detection through active-passive collaborative perception. In one or more embodiments of the invention, this node will be referred to as a "first perception node," for example... Figure 1 The sensor node 1 shown.

[0059] In practical application scenarios, there may be multiple sensing nodes that can achieve active and passive collaborative sensing, and the first sensing node can be any one of them.

[0060] Furthermore, when the first sensing node performs passive sensing, it may receive echoes reflected from multiple other sensing nodes after they have been sent to the target. In one or more embodiments of the present invention, only one such sensing node is used as an example and referred to as the "second sensing node," for example... Figure 1 The sensor node 2 is shown.

[0061] The following describes specific application scenarios where the above-mentioned sensing scenarios may exist.

[0062] The active-passive cooperative sensing method provided in this embodiment of the invention is applicable to any scenario where nodes with radar sensing capabilities perform active-passive cooperative sensing. Specifically, the application scenarios applicable to the active-passive cooperative sensing method provided in this embodiment of the invention can have the following characteristics:

[0063] 1. In passive sensing, there may or may not be a LOS path between the transmitting and receiving ends of the sensing nodes;

[0064] 2. The sensing node adopts a sensing method based on phase change estimation. That is, the sensing signal sent by the transmitting end is reflected by the target to the receiving end. The receiving end uses radar signal processing algorithms to extract phase change information, including target distance and velocity information, from the echo signal. Based on the phase change information, the target distance and velocity information are estimated. For example, radar sensing based on OFDM (Orthogonal Frequency-Division Muliplexing) signals.

[0065] Based on the above characteristics, the active and passive cooperative sensing method provided in this embodiment of the invention can be applied to most intelligent systems, such as multi-node cooperative sensing systems in the UAV swarm network neighborhood, multi-vehicle interconnected cooperative sensing systems in the intelligent transportation neighborhood, and multi-intelligent machine cooperative flexible manufacturing systems in the intelligent factory neighborhood.

[0066] The following examples, using vehicle traffic and flexible industrial manufacturing as examples, illustrate the application scenarios of the active-passive collaborative sensing method provided in this embodiment of the invention.

[0067] Figure 2 This is an example diagram of a vehicle traffic scenario provided in an embodiment of the present invention. To achieve high-precision, wide-range vehicle environment perception, base stations erected at high locations are the preferred choice for vehicle target detection. For example... Figure 2 As shown, both base station 1 and base station 2 can send sensing signals to targets 1 to L.

[0068] On the one hand, the base station can receive the echo signal reflected from the target by the detection signal it transmits, thus actively sensing the target, for example... Figure 2 The base station 2 shown can receive its own echo to achieve active sensing; on the other hand, the base station can also receive echo signals from neighboring base stations that have been reflected by the target, thus enabling passive sensing of the target, for example... Figure 2 The base station 2 shown can receive the echo reflected from the target after being sent by base station 1 to achieve passive sensing.

[0069] Furthermore, in vehicle environments, there are usually tall buildings, and it is difficult for base stations to have direct transmission paths due to the obstruction of buildings.

[0070] Figure 3This is an example diagram of an industrial flexible manufacturing scenario provided by an embodiment of the present invention. In this scenario, to obtain accurate factory environment perception information, AGVs (Automated Guided Vehicles) with perception capabilities need to actively and passively detect targets in the factory environment, such as... Figure 3 As shown, both AGV1 and AGV2 can detect targets 1 to L.

[0071] Similar to traffic environments, factory environments also have many obstacles that obstruct the view, and there may not be a direct transmission path between AGVs that perform active and passive sensing.

[0072] However, in passive sensing, the sensing nodes that transmit and receive signals, i.e., the transceiver ends, are spatially separated, making it difficult to guarantee strict time-frequency synchronization. This leads to TO and CFO in passive sensing. TO and CFO cause random phase changes in the echo signal, affecting the receiver's ability to estimate target parameters based on the phase change information of the echo signal. This results in serious target parameter estimation errors and reduces sensing performance.

[0073] by Figure 2 For example, since base station 1 and base station 2 are spatially separated, it is difficult for the two base stations to achieve precise time-frequency synchronization during passive sensing. Even with systems such as GPS / BeiDou for clock synchronization, the nanosecond-level clock synchronization accuracy will still cause nanometer-level target perception errors. Therefore, how to eliminate the time-frequency deviations (TO and CFO) between base stations during passive sensing is a key issue for base stations to achieve high-performance perception of the vehicle environment.

[0074] Specifically, if the TO and CFO in passive sensing cannot be eliminated, the target parameters estimated based on passive sensing will have serious errors and be unusable. Therefore, the echo signal received by base station 2 from the target transmitted by base station 1 is essentially an interference signal.

[0075] Therefore, during the sensing process of base station 2, only its own echo is a usable signal in the echo received by base station 2. The signal-to-interference-plus-noise ratio of the echo signal is low, and the target sensing performance is insufficient.

[0076] If TO and CFO in passive sensing can be eliminated, the interference echo signal reflected by the target from adjacent base stations can be converted into a useful signal that can be used to detect the target, thereby improving the signal-to-interference-plus-noise ratio of the echo signal received by the base station and thus obtaining better target sensing performance.

[0077] Furthermore, TO and CFO are not the only sources of error in passive sensing. Different locations of the transmitter and receiver can also lead to discrepancies in target delay and Doppler shift between active and passive sensing. Specific examples will illustrate this below. Figure 4 This is an example diagram illustrating the deviation between time delay and Doppler frequency shift in active and passive sensing provided in an embodiment of the present invention, as shown below. Figure 4 As shown, sensing node 1 and sensing node 2 jointly send sensing signals to the target / , and sensing node 1 realizes active and passive collaborative sensing of the target / .

[0078] Specifically, the latency is related to the distance between the sensing node and the target. For example... Figure 4 As shown, τ 1，l and τ 2，l Let τ represent the time delay information of target l when sensing node 1 performs active sensing and passive sensing, respectively. Since sensing nodes 1 and 2 are located at different positions, the distances between target l and sensing nodes 1 and 2 are R1 and R2, respectively. It is easy to understand that there is a path difference ΔR between the echo signals of active and passive sensing. Therefore, τ 1，l and τ 2，l There is a time delay difference Δτ l .

[0079] The Doppler shift is specifically related to the velocity between the sensing node and the target. For example... Figure 4 As shown, using f D，1，l and f D，2，l Let f represent the Doppler frequency shift information of target / when sensing node 1 performs active and passive sensing, respectively. The velocity of target / is v. Due to the different positions of sensing node 1 and sensing node 2, the velocity of target / is different in the directions of the two sensing nodes. Specifically, the velocity of target / in the receiving direction of sensing node 1 is v1, and the velocity in the transmitting direction of sensing node 2 is v2. Therefore, f D，1，l and f D，2，l There is a Doppler frequency shift difference Δf D，l .

[0080] Therefore, when sensing node 1 performs active and passive sensing of the same target, there is a time delay difference Δτ between active and passive sensing. l and Doppler frequency shift difference Δf D，l When performing active and passive collaborative sensing, it is necessary to compensate for this type of bias.

[0081] In related technologies, the alignment of time delay and Doppler frequency shift in active and passive sensing can be achieved through geometric relationships, which will not be elaborated here.

[0082] However, the method of alignment through geometric relationships is rather cumbersome and can only eliminate the time delay difference Δτ. l and Doppler frequency shift difference Δf D，lIf processing of TO and CFO is required, further operations are needed, so it is not very efficient when used to eliminate errors in passive sensing and improve sensing performance.

[0083] For ease of description, in one or more embodiments of the present invention, the term "frequency shift" may be used to refer to "Doppler frequency shift".

[0084] To address the aforementioned problems, this invention provides an active-passive collaborative sensing method, specifically applied to a first sensing node. Figure 5 This is a flowchart illustrating the first embodiment of the active-passive collaborative sensing method provided in this invention, as shown below. Figure 5 As shown, the method specifically includes the following steps:

[0085] Step S501: Receive the echo signal reflected by the target object.

[0086] Step S502: Based on the frequency band of the echo signal, separate the first echo signal and the second echo signal from the echo signal; wherein, the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node.

[0087] The first sensing node is any sensing node that performs active and passive collaborative sensing of the target object, and the second sensing node is the signal transmitting end of the first sensing node when it performs passive sensing.

[0088] Specifically, the echo signal received by the first sensing node is a fusion signal of primary and passive echo signals, and the first sensing signal and the second sensing signal are in different frequency bands. Therefore, the first echo signal and the second echo signal can be separated from the echo signal based on frequency division.

[0089] For ease of understanding, the signal transmission and reception of the first sensing node and the second sensing node in the embodiments of the present invention will be described exemplarily here.

[0090] In order to achieve active and passive coordinated perception of the target object, the first and second sensing nodes need to have the function of sending and receiving signals to the same area, and the first and second sensing signals sent are in different frequency bands.

[0091] As an example, the sensing node is equipped with a dual-antenna array that can transmit and receive signals simultaneously.

[0092] During the signal transmission phase, the first and second sensing nodes can communicate and share the location information of the target area that needs to be sensed collaboratively. Within the GPS synchronization accuracy, they can simultaneously generate sensing beams pointing to the collaborative area, and the sensing beams carry sensing signals.

[0093] The first and second sensing nodes can coordinate with each other during the signal transmission phase to ensure that the sensing signals transmitted by the two sensing nodes are in different frequency bands. This allows for the design of a filter with a matching frequency band at the first sensing node to separate the active and passive echo signals, i.e., the first echo signal and the second echo signal, from the active and passive echo fusion signal.

[0094] During the signal reception phase, the first sensing node can generate a signal receiving beam pointing towards the target area and receive the active and passive echo fusion signal reflected by the target object within it.

[0095] Step S503: Determine the first target sensing information for active sensing based on the first echo modulation symbol and the first transmitted modulation symbol; wherein, the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal.

[0096] Step S504: Determine the passively sensed second target sensing information based on the second echo modulation symbol and the second transmitted modulation symbol; wherein, the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal.

[0097] Taking OFDM signals as an example, the echo signal received by the first sensing node can be represented as:

[0098] y(t) = y1(t) + y2(t) + z(t)

[0099] Where t represents time, and z(t) represents the expression that follows the condition (0, σ). 2 Gaussian white noise vector with Gaussian distribution, σ 2 Let y1(t) represent the variance of the Gaussian distribution, and let y2(t) represent the received echo signal vectors of active and passive sensing, namely the first echo signal and the second echo signal, respectively.

[0100] In this embodiment of the invention, the echo modulation symbol is determined based on the echo signal, and the transmitted modulation signal is determined based on the sensing signal. Therefore, in the process of acquiring target sensing information of the target object, it is not necessary to directly process the sensing signal and the echo signal; instead, the modulation signal is treated as the processing object, which greatly simplifies the calculation. The modulation symbol is explained below with specific examples.

[0101] As an example, the echo signal received by the first sensing node itself, i.e., the first echo signal y1(t), and the echo signal reflected by the second sensing node from the target object, i.e., the second echo signal y2(t), can be represented as:

[0102]

[0103]

[0104] Where M and N represent the number of OFDM symbols and the number of subcarriers of the sensed signal, respectively, f n Let T represent the carrier frequency on the nth subcarrier, T represent the period of the OFDM symbol, and rect(·) represent the rectangular window function.

[0105] This represents the antenna reception steering vector, where, d is the distance between antennas, λ is the signal wavelength, and θ is the signal wavelength. l N is the angle of arrival of target l. a It refers to the number of antennas in the sensing node antenna array.

[0106] By performing a down-conversion operation, the received signal, i.e., y1(t) and y2(t), can be removed. By appropriately selecting the guard interval time of OFDM, the receiving end, i.e. the first sensing node, will cut the observed samples from the same OFDM symbol, thereby removing the rectangular function quantity rect(·) in the received signal.

[0107] Therefore, the echo modulation symbol received by the first sensing node from its own echo, i.e., the first echo modulation symbol, is specifically the m-th symbol received on the k-th antenna. The received modulation symbol on the n-th subcarrier can be represented as:

[0108]

[0109] Where, α 1，l d represents the channel attenuation magnitude of the l-th target in active sensing. 1，Tx (k, m, n) represents the m-th symbol transmitted on the k-th antenna, and the transmitted modulation symbol on the n-th subcarrier, i.e., the first transmitted modulation symbol, τ 1，l and f D，1，l Δf represents the time delay and Doppler shift of the l-th target during active sensing, respectively, and Δf represents the subcarrier spacing.

[0110] Similarly, the echo modulation symbol received by the first sensing node from the second sensing node, i.e., the second echo modulation symbol, can be represented as:

[0111]

[0112] Where, α 2，l d represents the channel attenuation magnitude of the l-th target in passive sensing. 1，Tx (k, m, n) represents the m-th symbol transmitted on the k-th antenna, and the transmitted modulation symbol on the n-th subcarrier, i.e., the second transmitted modulation symbol, δ τ (m) and δ f (m) represent the time-varying TO and CFO between the first and second sensing nodes, respectively, and τ 2，l and f D，2，l These represent the time delay and Doppler shift of the l-th target during passive sensing, respectively.

[0113] After determining the first echo modulation symbol, the first transmit modulation symbol, the second echo modulation symbol, and the second transmit modulation symbol, it is necessary to eliminate the transmit data information in the echo signal in order to obtain the target perception information.

[0114] As an example, a first transmitted signal matrix can be determined based on a first transmitted modulation symbol, a first received signal matrix can be determined based on a first received modulation symbol, and the first received signal matrix can be divided by the first transmitted signal matrix to obtain a first channel information matrix including first target sensing information.

[0115] Specifically, the first transmitted signal matrix D 1，Tx It can be represented as:

[0116]

[0117] First received signal matrix D 1，Rx It can be represented as:

[0118]

[0119] Then the first channel information matrix D 1，div for:

[0120]

[0121] Similar to active sensing, in passive sensing, a second transmitted signal matrix can be determined based on the second transmitted modulation symbol, a second received signal matrix can be determined based on the second received modulation symbol, and the second received signal matrix can be divided by the second transmitted signal matrix to obtain a second channel information matrix that includes the second target sensing information.

[0122] Specifically, the second transmitted signal matrix D 2，Tx It can be represented as:

[0123]

[0124] Second received signal matrix D 2，Rx It can be represented as:

[0125]

[0126] Then the second channel information matrix D 2，div for:

[0127]

[0128] Step S505: Separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information.

[0129] Step S506: Separate the second time delay sensing information and the second frequency shift sensing information from the second target sensing information; the second time delay sensing information includes time deviation; the second frequency shift sensing information includes carrier frequency deviation.

[0130] Specifically, the time delay sensing information and frequency shift sensing information included in the target sensing information are orthogonal. Therefore, it is possible to separate the time delay sensing information and frequency shift sensing information from the target sensing information, which facilitates the separate processing of the time delay sensing information and frequency shift sensing information in subsequent steps and simplifies the calculation.

[0131] As an example, in active sensing, the first channel information matrix can be represented as the Kronecker product of two vectors, namely the Kronecker product of the first time delay sensing information and the first frequency shift sensing information, specifically expressed as follows:

[0132] D 1，div =k 1，R ×k 1，D

[0133]

[0134]

[0135] Where, k 1，R (k) represents the first time-delay sensing information, k 1，D (k) represents the first frequency shift sensing information, and L represents the number of targets. Based on k 1，R (k) and k 1，D (k) can estimate the distance and velocity information of the target object in active perception.

[0136] Similarly, in passive sensing, the second channel information matrix can be represented as the Kronecker product of two vectors, namely the Kronecker product of the second time delay sensing information and the second frequency shift sensing information, specifically expressed as follows:

[0137] D 2，div =k 2，R ×k 2，D

[0138]

[0139]

[0140] Where, k 2，R (k) represents the second time-delay sensing information, k 2，D (k) represents the second frequency shift sensing information.

[0141] From the above formula, we can see that k 2，R The phase information of (k) includes TO, i.e., δ τ (m), and the time delay information τ 2， l and the time delay information τ in active sensing 1，l There is a time delay difference Δτ l Similarly, k 2，D The phase information of (k) includes CFO, i.e., δ f (m), and frequency shift information f 2，D，l and frequency shift information f in active sensing 1，D，l There is a frequency shift difference Δf D，l .

[0142] It should be understood that during the active sensing process at the first sensing node, the specific information needed is the distance and velocity information of the target object relative to the first sensing node. Therefore, if directly based on k... 2，R (k) and k 2，D (k) Estimating the distance and velocity information of the target object will produce serious estimation errors and reduce perception performance.

[0143] Therefore, in embodiments of the present invention, it is necessary to process Δτ in the second time delay sensing information. l and TO, and Δf in the second frequency shift sensing information. D，l Eliminate the CFO.

[0144] To address this issue, this invention proposes a Cooperative-Sensing Cross-Correlation (CSCC) algorithm to achieve the following for TO and CFO, as well as Δτ. l and Δf D，l The elimination of [the substance] will be explained below in conjunction with steps S507-S510.

[0145] Step S507: Perform correlation processing on the first time delay sensing information and the second time delay sensing information to obtain time delay error sensing information.

[0146] The relevant operations involved in the embodiments of the present invention will be described below with specific examples. For ease of description, it is assumed that the first sensing node only senses one target object, i.e., L=1, and the target is defined as l.

[0147] Furthermore, during the relevant operations, the same operation can be performed on the signals received by each antenna. Therefore, this embodiment of the invention takes the 0th antenna as an example. For ease of description, let's further assume α 1，l =α 2，l =1, then the first time delay sensing information and the second time delay sensing information are represented as follows:

[0148]

[0149]

[0150] It can be seen that both the first and second time delay sensing information include time delay sensing information on the first to Nth subcarriers.

[0151] The first and second time delay sensing information are subjected to correlation processing, namely, the phase information deviation between the first and second time delay sensing information on the corresponding subcarriers is extracted.

[0152] Taking the Nth subcarrier as an example, that is, extracting and The phase information deviation between them can be specifically obtained This refers to the delay error sensing information on the Nth subcarrier. Therefore, the delay error sensing information on each subcarrier can be obtained.

[0153] As can be seen, in the embodiments of the present invention, by adjusting k 1，R and k 2，R After relevant processing, the obtained time delay error perception information only contains Δτ. l +δ τ (m) phase information, thereby enabling the extraction of time delay errors in passive sensing.

[0154] Step S508: Construct a time delay error perception vector based on the first time delay perception information and the time delay error perception information, perform relevant processing on the second time delay perception information and the time delay error perception vector to obtain the third time delay perception information; both the third time delay perception information and the first time delay perception information are used to obtain the distance information of the target object.

[0155] As mentioned above, multiple delay error sensing information can be obtained based on step S507. Therefore, the delay error sensing information can be constructed into a delay error sensing vector based on the arrangement order of the elements in the first or second delay sensing information. Thus, when performing correlation processing on the second delay sensing information and the delay error sensing vector, the corresponding elements of the second delay sensing information and the delay error sensing vector correspond to the same subcarrier, enabling the elimination of errors in the second delay sensing information on each subcarrier.

[0156] As an example, the latency error perception vector is:

[0157]

[0158] Taking the Nth subcarrier as an example, after performing correlation processing on the second delay sensing information and the delay error sensing vector, it is possible to obtain The time delay error in its phase information is eliminated.

[0159] As an example, the first and second time-delay sensing information can be processed based on the following formula:

[0160]

[0161] Where, ρ R Let be the time delay error sensing vector, and diag(·) denotes the transformation of the vector into a diagonal matrix. H is the conjugate transpose symbol.

[0162] The above formula can be used to directly construct the time delay error perception information into a time delay error perception vector, which simplifies the calculation.

[0163] As an example, by processing the second time delay perception information and the time delay error perception information, we can obtain:

[0164]

[0165] Where, k′ 2，R This is the third time delay sensing information. It can be seen that, through correlation processing of the second time delay sensing information and the time delay error sensing information, the phase of the obtained third time delay sensing information does not include Δτ. l +δ τ (m), thereby eliminating the time delay error in passive sensing.

[0166] Based on k′ 2，R It can obtain distance information of target objects in passive sensing. For specific operations, please refer to the relevant technology.

[0167] As an example, we can consider k′ 2，RPerform an IDFT (Inverse Discrete Fourier Transform) operation to obtain the distance information of the target object.

[0168] Based on k 1，R This enables the acquisition of distance information of target objects in active perception, thereby achieving active and passive collaborative perception of the distance information of target objects.

[0169] Step S509: Perform correlation processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information.

[0170] Based on the same assumptions as in step S507, the first frequency shift sensing information and the second frequency shift sensing information can be simplified as follows:

[0171]

[0172]

[0173] It can be seen that both the first and second frequency shift sensing information include frequency shift sensing information from the first symbol to the Mth symbol.

[0174] Correlation processing is performed on the first frequency shift sensing information and the second frequency shift sensing information, that is, the phase information deviation of the first frequency shift sensing information and the second frequency shift sensing information on the corresponding symbols is extracted.

[0175] Taking the Mth symbol as an example, that is, extracting... and The phase information deviation between them can be specifically obtained This refers to the frequency shift error sensing information on the Mth symbol. Therefore, the frequency shift error sensing information on each symbol can be obtained.

[0176] As can be seen, in the embodiments of the present invention, by adjusting k 1，D and k 2，D After relevant processing, the obtained frequency shift error sensing information only contains Δf D，l +δ f (m) phase information, thereby enabling the extraction of frequency shift errors in passive sensing.

[0177] Step S510: Construct a frequency shift error sensing vector based on the first frequency shift sensing information and the frequency shift error sensing information, perform correlation processing on the second frequency shift sensing information and the frequency shift error sensing vector to obtain the third frequency shift sensing information; both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

[0178] As mentioned above, multiple frequency shift error sensing information can be obtained based on step S509. Therefore, the frequency shift error sensing information can be constructed into a frequency shift error sensing vector based on the arrangement order of the elements in the first or second frequency shift sensing information. Thus, when performing correlation processing on the second frequency shift sensing information and the frequency shift error sensing vector, the corresponding elements of the second frequency shift sensing information and the frequency shift error sensing vector correspond to the same symbol, enabling the elimination of errors in the second frequency shift sensing information at each symbol.

[0179] As an example, the frequency shift error sensing vector is:

[0180]

[0181] Taking the Mth symbol as an example, after performing correlation processing on the second frequency shift sensing information and the frequency shift error sensing vector, we can obtain... The frequency shift error in its phase information is eliminated.

[0182] As an example, the first frequency shift sensing information and the second frequency shift sensing information can be processed based on the following formula:

[0183]

[0184] Where, ρ D This is the frequency shift error sensing vector.

[0185] As an example, by performing relevant processing on the second frequency shift sensing information and the frequency shift error sensing information, we can obtain:

[0186]

[0187] Where, k′ 2，D This is the third frequency shift sensing information. It can be seen that, through correlation processing of the second and frequency shift error sensing information, the phase of the obtained third frequency shift sensing information does not include Δf. D，l +δ f (m), thereby eliminating frequency shift error in passive sensing.

[0188] Based on k′ 2，D It can obtain the speed information of passively sensed target objects. For specific operations of this part, please refer to the relevant technology.

[0189] As an example, we can consider k′ 2，D The DFT (Discrete Fourier Transform) operation is performed to obtain the velocity information of the target object.

[0190] Based on k 1，DThis enables the acquisition of velocity information of target objects in active perception, thereby achieving active and passive collaborative perception of the velocity information of target objects.

[0191] The active-passive collaborative sensing method provided in this invention separates the first actively sensed echo signal and the second passively sensed echo signal from the echo signal according to the frequency band of the echo signal. Based on the echo signal and the sensing signal, it determines the first actively sensed target sensing information and the second passively sensed target sensing information. From the first target sensing information, it separates the first actively sensed time delay sensing information and the first frequency shift sensing information, and from the second target sensing information, it separates the second passively sensed time delay sensing information and the second frequency shift sensing information. This allows for separate processing of the time delay sensing information and frequency shift sensing information of the target object, simplifying the calculation. By performing correlation processing on the first and second time-delay sensing information, the time delay difference and TO in passive sensing are extracted, obtaining time delay error information and constructing a time delay error sensing vector. Then, correlation processing is performed on the second time-delay sensing information and the time delay error sensing vector to eliminate the time delay difference and TO from the second time-delay sensing information. Similarly, by performing correlation processing on the first and second frequency shift sensing information, the frequency shift difference and CFO in passive sensing are extracted, obtaining frequency shift error information and constructing a frequency shift error sensing vector. Then, correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to eliminate the frequency shift difference and CFO from the second frequency shift sensing information. By actively sensing to assist in eliminating the time delay difference, frequency shift difference, TO, and CFO in the target sensing information in passive sensing, the second echo signal is transformed from an interference signal into a useful signal, which can improve the signal-to-interference-plus-noise ratio of the echo signal received by the first sensing node, thereby improving sensing performance.

[0192] Furthermore, the active-passive collaborative sensing method provided in this embodiment of the invention achieves complete elimination of time delay difference, frequency shift difference, TO and CFO, without requiring further processing of time delay difference and frequency shift difference through geometric alignment, and has high processing efficiency.

[0193] Furthermore, the embodiments of the present invention are also applicable to scenarios where there are obstacles between the passive sensing transceivers, thus having a wide range of applications.

[0194] It is worth noting that the CSCC algorithm proposed in the first embodiment of the present invention is specifically based on the assumption that there is only one target object in the environment, that is, the first sensing node can only receive the echo signal reflected by one target object.

[0195] If there are multiple target objects in the environment, the first echo signal and the second echo signal extracted in the aforementioned step S502 are essentially echo signals that fuse the phase change information of the corresponding multiple target objects. In order to achieve passive perception of target objects, it is actually necessary to obtain the echo signal that includes the phase change information of each target object and the error information corresponding to each target object in the passive perception.

[0196] When multiple target objects exist in the environment, executing step S507 cannot extract the time delay error information of a single target, i.e., Δτ. l + τ ( ), therefore, the time delay error in passive sensing cannot be eliminated through subsequent steps, nor can the distance information of the target object in passive sensing be obtained. Similarly, in this case, executing step S509 cannot extract the frequency shift error information of a single target, i.e., Δf D,l + f (), it is impossible to eliminate the frequency shift error in passive sensing through subsequent steps, and it is also impossible to obtain the velocity information of the target object in passive sensing.

[0197] To address this issue, in the second embodiment of the present invention, instead of directly processing the second time delay sensing information and time delay error sensing information, or processing the second frequency shift sensing information and frequency shift error sensing information to obtain error-free sensing information, the phase change information from active sensing, the phase change information from passive sensing, and the error phase information from error sensing information are extracted separately. Then, phase alignment is performed, that is, the active sensing phase change information, passive sensing phase change information, and error phase information corresponding to the same target object are identified, thereby achieving coordinated active and passive sensing of the target object.

[0198] Taking target object l as an example, the parameter information of the target object in active perception can be obtained based on the phase change information of active perception, the parameter information of the target object in passive perception can be obtained based on the phase change information of passive perception, and the deviation between the parameter information of the target object in active and passive perception can be obtained based on the error phase information, thereby obtaining the parameter information of the target object under active and passive collaborative perception.

[0199] The following is a detailed description of this embodiment. Based on the aforementioned steps S501-S506, the second embodiment of the present invention provides a method for processing time delay sensing information and frequency shift sensing information in a multi-target scenario. Figure 6 This is a flowchart illustrating the second embodiment of the active-passive collaborative sensing method provided in this invention, as shown below. Figure 6 As shown, the specific steps include:

[0200] Step S601: Perform correlation processing on the first time delay sensing information and the second time delay sensing information to obtain time delay error sensing information.

[0201] In explaining step S507, for ease of description, only one antenna is used as an example. However, when there are multiple target objects in the environment, the perceived time delay error on different antennas may be different. Therefore, a new example will be used for explanation here.

[0202] As an example, the first time-delay sensing information on the k-th antenna can be represented as:

[0203]

[0204] The second time-delay sensing information on the k-th antenna can be represented as:

[0205]

[0206] By performing correlation processing on the first and second time delay sensing information on the k-th antenna, the time delay error sensing information ρ on the k-th antenna can be obtained. R (k):

[0207]

[0208] Step S602: Perform IDFT operation on the time delay error sensing information to obtain the time delay error phase information sequence.

[0209] Taking the IDFT operation on the time delay error sensing information on the 0th antenna as an example, i.e., k=0, it can be specifically represented as follows:

[0210]

[0211] Through the IDFT operation described above, a sequence of time delay error phase information can be obtained.

[0212] It can be seen that the time delay error phase information obtained in this step includes TO, i.e., δ. τ (m), and the active and passive time delay difference between target objects l2 and l1, but in the actual embodiment of the present invention, what is needed is the active and passive time delay difference for the same target object, i.e., l2 = l1. Therefore, only part of the data in the time delay error phase information sequence is valid data.

[0213] Step S603: Perform IDFT operation on the first time delay sensing information to obtain the first time delay phase information sequence of active sensing; each first time delay phase information corresponds to a target object.

[0214] By sensing the first time delay, i.e. k 1，R By performing the IDFT operation, the first time-delay phase information sequence {τ} of active sensing can be obtained. 1，0 , ..., τ 1，l , ..., τ 1，L-1 For specific steps, please refer to the relevant technical documentation.

[0215] It can be seen that each first time delay phase information corresponds to a target object.

[0216] Step S604: Perform IDFT operation on the second time delay sensing information to obtain the passively sensed second time delay phase information sequence; each second time delay phase information corresponds to a target object.

[0217] Similarly to step S603, by sensing the second time delay information, i.e. k 2，R By performing the IDFT operation, the second time-delay phase sensing information sequence {τ} of passive sensing can be obtained. 2，0 +δ τ (m), ..., τ 2，l +δ τ (m), ..., τ 2，L-1 +δ τ (m)}.

[0218] It can be seen that each item of the second time delay phase information corresponds to a target object.

[0219] Step S605: For the first object in the target objects, determine the time delay error phase information, the first time delay phase information and the second time delay phase information corresponding to the first object according to the first preset matching condition; the first preset matching condition is: the sum of the time delay error phase information and the first time delay phase information is equal to the second time delay phase information; the time delay error phase information, the first time delay phase information and the second time delay phase information corresponding to the first object are used to obtain the distance information of the first object.

[0220] Here, the first object is any target object. Taking target object l as an example, the corresponding first preset matching condition is (τ). 2，l -τ 1，l +δ τ (m))+τ 1，l =τ 2，l +δ τ (m).

[0221] As an example, the elements in the first time delay phase information sequence, the second time delay phase information sequence, and the time delay error phase information sequence can be traversed to find the elements that satisfy the first preset matching condition. Each set of first time delay phase information, second time delay phase information, and time delay error phase information that satisfies the condition is considered to belong to the same target object, and the time delay error phase information therein satisfies l2 = l1.

[0222] Upon completion of step S605, the temporal delay phase information alignment between active and passive sensing is achieved, thereby enabling collaborative active and passive sensing of the distance information of the target object.

[0223] Step S606: Perform correlation processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information.

[0224] As an example, the first frequency shift sensing information on the k-th antenna can be represented as:

[0225]

[0226] The second frequency shift sensing information on the k-th antenna can be represented as:

[0227]

[0228] By performing correlation processing on the first and second frequency shift sensing information on the k-th antenna, the frequency shift error sensing information ρ on the k-th antenna can be obtained. D (k):

[0229]

[0230] Step S607: Perform a DFT operation on the frequency shift error sensing information to obtain a frequency shift error phase information sequence.

[0231] It is worth noting that the accuracy of the frequency shift error phase information sequence obtained through step S607 may be affected by the CFO attribute, which can be divided into the following two cases:

[0232] When the CFO remains almost constant throughout the entire M OFDM symbols of the sensing signal, that is:

[0233] δ f (0) = , ..., = δ f (m) = , ..., = δ f (M-1)

[0234] In this case, the frequency shift error phase information sequence can be obtained directly using DFT operations.

[0235] When the CFO is time-varying over the entire M OFDM symbols of the sensing signal, that is:

[0236] δ f (0)≠,...,≠δ f (m)≠,...,≠δ f (M-1)

[0237] At this point, under different OFDM symbols m, δ f (m) are also different, therefore the frequency shift error phase information for the same target is not a constant value. In δ f When (m) does not change significantly, the frequency shift error phase information sequence can be directly obtained using DFT operations, but when δ f When (m) varies significantly, the accuracy of the calculation results may decrease.

[0238] To address this issue, in one specific embodiment of the present invention, the sensing node can generate sensing signals using a highly stable quartz clock crystal oscillator, achieving a CFO with minimal variation, thereby improving the performance of active-passive collaborative sensing.

[0239] By performing a DFT operation on the frequency shift error sensing information, a sequence of frequency shift error phase information can be obtained.

[0240] Similar to step S602, the frequency shift error phase information obtained in this step includes CFO, i.e., δ. f (m), and the active and passive frequency shift difference between target objects l2 and l1, but in the actual embodiment of the present invention, what is needed is the active and passive frequency shift difference for the same target object, i.e., l2 = l1. Therefore, only part of the data in the frequency shift error phase information sequence is valid data.

[0241] Step S608: Perform a DFT operation on the first frequency shift sensing information to obtain the first frequency shift phase information sequence of active sensing; each first frequency shift phase information corresponds to a target object.

[0242] By sensing the first frequency shift information, i.e. k 1，D By performing a DFT operation, the first frequency shift phase information sequence {f} of the active sensing can be obtained. 1，0 , ..., f 1，l , ..., f 1，L-1}

[0243] It can be seen that each first frequency shift phase information corresponds to a target object.

[0244] Step S609: Perform a DFT operation on the second frequency shift sensing information to obtain a passively sensed first frequency shift phase information sequence; each second frequency shift phase information corresponds to a target object.

[0245] By sensing the second frequency shift information, i.e. k 2，D By performing a DFT operation, the second frequency shift phase information sequence {f} of passive sensing can be obtained. 2，0 +δ f (m), ..., f 2，l +δ f (m), ..., f 2，L-1 +δ f (m)}.

[0246] It can be seen that each second frequency shift phase information corresponds to a target object.

[0247] Step S610: For the first object in the target object, determine the frequency shift error phase information, the first frequency shift phase information and the second frequency shift phase information corresponding to the first object according to the second preset matching condition; the second preset matching condition is: the sum of the frequency shift error phase information and the first frequency shift phase information is equal to the second frequency shift phase information; the frequency shift error phase information, the first frequency shift phase information and the second frequency shift phase information corresponding to the first object are used to obtain the velocity information of the first object.

[0248] Taking the target object l as an example, the corresponding second preset matching condition is (f 2，l -f 1，l +δ f (m))+f 1，l =f 2，l +δ f (m).

[0249] As an example, the elements in the first frequency shift phase information sequence, the second frequency shift phase information sequence, and the frequency shift error phase information sequence can be traversed to find the elements that satisfy the second preset matching condition. Each set of first frequency shift phase information, second frequency shift phase information, and frequency shift error phase information that satisfies the condition is considered to belong to the same target object, and the frequency shift error phase information therein satisfies l2 = l1.

[0250] Upon completion of step S611, the frequency shift phase information alignment between active and passive sensing is achieved, thereby enabling coordinated active and passive sensing of the target object's velocity information.

[0251] In this embodiment of the invention, by performing an IDFT operation on the first time delay error sensing information, a time delay error phase information sequence is obtained, and an actively sensed first time delay phase information sequence and a passively sensed second time delay phase information sequence are acquired. The time delay error phase information, the first time delay phase information and the second time delay phase information corresponding to the same target object are found through a first preset matching condition, thereby realizing the alignment of the time delay phase information of the target object in active and passive sensing, and thus enabling active and passive collaborative sensing of the distance information of the target object.

[0252] Similarly, in this embodiment of the invention, a frequency shift error phase information sequence is obtained by performing a DFT operation on the first frequency shift error sensing information, and a first frequency shift phase information sequence of active sensing and a second frequency shift phase information sequence of passive sensing are obtained. The frequency shift error phase information, the first frequency shift phase information and the second frequency shift phase information corresponding to the same target object are found by using a second preset matching condition, thereby realizing the alignment of the frequency shift phase information of the target object in active and passive sensing, and thus enabling active and passive collaborative sensing of the velocity information of the target object.

[0253] It is worth noting that in the second embodiment of the present invention, in the time delay error phase information sequence obtained by step S602, the time delay difference in some of the time delay error phase information is between different target objects. This part of the time delay error phase information cannot be used to perceive the target object and is called "interference item". The actually useful data is the time delay error phase information for a single target, which is called "single target time delay error phase information".

[0254] Ideally, the time delay error phase information extracted through the first preset matching condition in step S60 can be considered as the single-target time delay error phase information. However, some interference terms may also satisfy the first preset matching condition. To further improve the accuracy of phase information alignment and enhance perception performance, in the third embodiment of the present invention, the single-target time delay error phase information can be extracted from the time delay error phase information sequence first, and then the phase information can be aligned according to the first preset matching condition.

[0255] The processing of the frequency shift error phase information sequence is similar and will not be elaborated here.

[0256] Based on this, a third embodiment of the present invention will now be described in detail. In this embodiment of the present invention, the first sensing node specifically includes a first antenna and one or more second antennas.

[0257] As an example, the time delay error perception information obtained in step S601 specifically satisfies the following formula:

[0258]

[0259] in,

[0260] β R (n, k) = D R (n, k) + I R (n, k)

[0261] The aforementioned time delay error perception information specifically includes single-target time delay perception information D. R (n, k), and interference term I R (n, k).

[0262] Among them, D R The phase information in (n, k) is the same on any two antennas, i.e., D R The phase information of (n, k) is independent of the antenna subscript k, while I R The phase information of (n, k) will change as the antenna index k changes.

[0263] Specifically, since a single target is consistent in direction, the phase information for a single target is the same on each antenna. Therefore, the part of the phase information in the time delay error perception information that does not change with k is the single target time delay perception information, which is the effective data required in the time delay error perception information when performing target perception.

[0264] The time delay error sensing information that integrates the phase information of multiple targets, for example, the time delay error sensing information obtained from the sensing signal sent by the second sensing node to the l1st target and the echo signal received by the first sensing node from the l2th target, will change with the antenna index k due to the different positions of the targets.

[0265] In short, the effective data required in this step of the embodiments of the present invention is specifically the phase information corresponding to the part of the time delay error perception information that does not change with k, that is, the time delay error phase information of a single target.

[0266] Based on the above properties, β can be removed by continuously adjusting the coefficient k. R The amount of phase change in (n, k) I R (n, k), thereby realizing the phase information of the time delay error of a single target, i.e., Δτ l +δ τ Estimate (m).

[0267] Specifically, step S602 mentioned above may include the following sub-steps:

[0268] Perform an IDFT operation on the time delay error sensing information, obtain the index of the IDFT operation result at the peak, and obtain the phase information sequence of time delay error containing interference.

[0269] Extract the delay error phase information sequence corresponding to the single-target delay error perception information from the phase information sequence containing interference delay error.

[0270] Taking the 0th antenna as an example, the time delay error sensing information ρ R (0) Using the IDFT algorithm, we can obtain the following:

[0271]

[0272] Then when

[0273]

[0274] At that time, the IDFT operation result will show a peak.

[0275] It can be seen that the index at which the IDFT operation result reaches a peak, i.e., the phase information in q, contains the phase information of the interference delay error, specifically including the phase information of the delay error of a single target and the phase information of the delay error of fused multiple targets. Therefore, multiple indices q corresponding to each peak can be recorded. i To obtain the phase information sequence containing interference delay error, i.e.

[0276] Then, single-target time delay error sensing information, i.e., D, is extracted from the phase information sequence containing interference time delay error. R By obtaining the time delay error phase information corresponding to (n, k), the time delay error phase information {Δτ} for a single target in this embodiment of the invention can be obtained. l +δ τ (m)}, l=0,…,L-1.

[0277] In this embodiment of the invention, the step of extracting the time delay error phase information sequence is not specifically limited.

[0278] As an example, IDFT operations can be performed on the time delay error sensing information on each antenna. By continuously adjusting the value of k, it can be determined whether the phase information changes with k, thereby extracting D from the phase information sequence containing interference time delay error. R (n, k) corresponds to the time delay error phase information sequence for a single target.

[0279] After obtaining the time delay error phase information for a single target, the time delay error phase information, the first time delay phase information, and the second time delay phase information of the same target object can be matched according to the aforementioned step S605.

[0280] As an example, the registration phase space P is obtained from the time delay error phase information sequence. g :

[0281] P g =Set(Δτ0+δ τ (m), ..., Δτ l +δ τ (m), ..., Δτ L-1 +δ τ (m))

[0282] The active sensing phase space P is obtained based on the first time delay phase information sequence. m :

[0283] P m =Set(τ 1，0 , ..., τ 1，l , ..., τ 1，L-1 )

[0284] The phase space P of bidirectional sensing is obtained based on the second time-delay phase information sequence. b :

[0285] P b =Set(τ 2，0 +δ τ (m), ..., τ 2，l +δ τ (m), ..., τ 2，L-1 +δ τ (m))

[0286] By analyzing P g P m and P b The elements in the array are traversed to obtain the phase information combinations that satisfy the first preset matching condition, thus realizing the phase alignment of the sensing in the ranging aspect. The first preset matching condition is:

[0287] P m (i)+P g (i)==P b (i)

[0288] The processing of frequency shift error sensing information is similar to that of time delay error sensing information. As an example, the frequency shift error sensing information obtained in step S612 can specifically satisfy the following formula:

[0289]

[0290] in,

[0291]

[0292] Similar to the previous text, D v The frequency domain error phase information corresponding to (m, k) is the frequency shift error phase information of a single target.

[0293] In this embodiment of the present invention, the aforementioned step S613 may specifically include the following sub-steps:

[0294] Perform a DFT operation on the frequency shift error sensing information, obtain the index of the DFT operation result at the peak, and obtain the phase information sequence of frequency shift error containing interference.

[0295] Extract the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the frequency shift error phase information sequence containing interference.

[0296] Specifically, the above steps are used to obtain the phase information sequence {f} containing interference frequency shift error. 2，l -f 1，l +δ f After (m)}, extract D from it. v By obtaining the phase information corresponding to (m, k), the frequency shift error phase information sequence {Δf} for a single target can be obtained. l +δ f (m)}.

[0297] For details on this part, please refer to the processing of time delay error perception information; it will not be elaborated here.

[0298] In this embodiment of the invention, by performing an IDFT operation on the time delay error sensing information, a sequence of time delay error phase information containing interference is obtained, and time delay error phase information for a single target is extracted from it. This improves the accuracy of time delay phase information alignment when matching the time delay error phase information sequence, the first time delay phase information, and the second time delay phase information of the same target, thereby improving the accuracy of distance sensing of target objects in active and passive cooperative sensing.

[0299] Similarly, in this embodiment of the invention, by performing a DFT operation on the frequency shift error sensing information, a sequence of frequency shift error phase information containing interference is obtained, and frequency shift error phase information for a single target is extracted from it. Thus, when matching the frequency shift error phase information sequence, the first frequency shift phase information and the second frequency shift phase information of the same target, the accuracy of frequency shift phase information alignment can be improved, thereby improving the accuracy of velocity sensing of target objects in active and passive cooperative sensing.

[0300] In the fourth embodiment of the present invention, a specific implementation method is provided for extracting the delay error phase information sequence of a single target from the interference delay error phase information sequence and extracting the frequency shift error phase information sequence of a single target from the interference frequency shift error phase information sequence.

[0301] In this embodiment of the invention, the first sensing node includes a first antenna and one or more second antennas.

[0302] The following example illustrates this further. As mentioned earlier, the time delay error perception information specifically satisfies the following formula:

[0303]

[0304] in,

[0305] β R (n, k) = D R (n, k) + I R (n, k)

[0306] In a specific embodiment of the present invention, in order to avoid the phase information being overwhelmed by interference, the phase amplitude can be increased before performing IDFT operation on the time delay error sensing information. As an example, this can be achieved in the following way.

[0307] For N a All antennas undergo the above-mentioned calculation of time delay error sensing information ρ. R The operation of (k) is performed, and the vector sum is calculated:

[0308]

[0309]

[0310] In the fourth embodiment of the present invention, after the aforementioned steps of performing an IDFT operation on the time delay error sensing information, obtaining the index of the IDFT operation result at the peak, and obtaining the phase information sequence containing the interference time delay error, the method further includes:

[0311] Obtain the real part of the IDFT operation result corresponding to each phase information containing interference delay error, and obtain the delay IDFT result sequence.

[0312] Taking the 0th antenna as an example, when performing IDFT on the time delay error sensing information, the index q corresponding to the peak value is recorded. 0，i and its r(q) 0，i The real part of ) is real(r(q) 0，i Let P0 be the set of the set P0.

[0313] P0={(q 0，i ,real(r(q) 0，i )))},i=0,1,...

[0314] This allows us to obtain a sequence of time-delayed IDFT results, where each time-delayed IDFT result is real(r(q)). 0，i )).

[0315] The aforementioned steps for extracting the single-target time delay error phase information sequence corresponding to the target time delay error sensing information from the phase information sequence containing interference time delay error can specifically include the following sub-steps:

[0316] For each delayed IDFT result on the first day, calculate the first difference with the corresponding delayed IDFT result on the second day in sequence.

[0317] If the first difference is greater than the preset threshold, the interference-containing time delay error phase information corresponding to the time delay IDFT result is deleted from the interference-containing time delay error phase information sequence of the first antenna, and the time delay error phase information sequence is obtained.

[0318] As an example, an error threshold can be preset, i.e., a preset threshold ε.

[0319] The following description uses the 0th antenna as the first antenna to illustrate this embodiment of the present invention.

[0320] After obtaining the set P0 for the 0th antenna, i.e., when k = 0, repeat the same steps to obtain the set P for each antenna. k , k < N a This means that the time delay DFT results for each antenna are obtained.

[0321] Then, iterate through all elements (q) in P0. 0，i ,real(r(q) 0，i If |real(r(q) 0，i ))-real(r(q k，i ))|≥ε, that is, the time-delayed IDFT result in P0 is equal to that in P. k If the first difference between the corresponding time-delay DFT results is greater than a preset threshold, then (q) 0，i ,real(r(q) 0，i Remove from P0.

[0322] For each second line, i.e., from k=1 to k=N a Perform the above operations until there are no more elements to be deleted in P0, and finally obtain the set q in P0. 0，i The phase information, i.e., the phase information sequence of the time delay error of a single target {Δτ}. l +δ τ (m)}, l=0,...,L-1.

[0323] Specifically, after performing an IDFT operation on the time delay error sensing information, if the real part of the IDFT operation result, i.e., the difference between the time delay IDFT results on any two antennas, is not less than a preset threshold, then the time delay IDFT result is considered not to change with the change of k. Therefore, this part of the time delay IDFT result can be considered as D. R The time delay IDFT result corresponding to (n, k) is obtained. Therefore, by obtaining the time delay error phase information corresponding to this part of the time delay IDFT result, the time delay error phase information for a single target is obtained.

[0324] Based on the same principle, in the fourth embodiment of the present invention, after the aforementioned steps of performing a DFT operation on the frequency shift error sensing information, obtaining the index of the DFT operation result at the peak, and obtaining the phase information sequence containing the interference frequency shift error, the method further includes:

[0325] Obtain the real part of the DFT operation result corresponding to each phase information containing interference frequency shift error, and obtain the frequency shift DFT result sequence.

[0326] The aforementioned steps extract the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the interference-containing frequency shift error phase information sequence, specifically including the following sub-steps:

[0327] For each frequency-shifted DFT result on the first day, calculate the second difference with the corresponding frequency-shifted DFT result on the second day in turn.

[0328] If the second difference is greater than the preset threshold, the interference-containing frequency shift error phase information corresponding to the frequency shift DFT result is deleted from the interference-containing frequency shift error phase information sequence of the first antenna, and the frequency shift error phase information sequence is obtained.

[0329] Based on the above steps, the frequency shift error phase information sequence {Δf} for a single target can be obtained. l +δ f (m)}, l=0,...,L-1.

[0330] Since the above steps are based on the same principle as the processing of time delay error phase information in the previous text, the specific details can be found in the previous description.

[0331] In the fourth embodiment of the present invention, after performing an IDFT operation on the time delay error sensing information, the real part of the phase information containing the interference time delay error and the corresponding IDFT operation result is obtained to obtain a time delay IDFT result sequence. The first difference between the time delay IDFT result on the first day line and the corresponding time delay IDFT result on the second day line is calculated. The phase information corresponding to the time delay IDFT result with the first difference greater than a preset threshold is deleted from the time delay error phase information sequence containing the interference time delay error, thereby obtaining a time delay error phase information sequence for a single target.

[0332] Similarly, in this embodiment of the invention, after performing a DFT operation on the frequency shift error sensing information, the real part of the frequency shift error phase information containing interference and the corresponding DFT operation result is obtained to obtain a frequency shift DFT result sequence. The second difference between the frequency shift DFT result on the first day line and the corresponding frequency shift DFT result on the second day line is calculated. The phase information corresponding to the frequency shift DFT result with the second difference greater than a preset threshold is deleted from the frequency shift error phase information sequence containing interference, thereby obtaining a frequency shift error phase information sequence for a single target.

[0333] In this embodiment of the invention, by determining whether the real part of the IDFT / DFT operation result changes on different antennas, it is determined whether the phase information corresponding to the real part of the IDFT / DFT operation result is for the same target object. This enables the extraction of a single target delay error phase information sequence corresponding to the target delay error perception information from a phase information sequence containing interference delay error, or the extraction of a single target frequency shift error phase information sequence corresponding to the target frequency shift error perception information from a phase information sequence containing interference frequency shift error, which has high computational efficiency and accuracy.

[0334] In one embodiment of the present invention, the first sensing signal and the second sensing signal are OFDM signals.

[0335] Figure 7 This is a schematic diagram of an active-passive cooperative sensing method provided in an embodiment of the present invention. For ease of understanding, the following is combined with... Figure 7 The active-passive cooperative sensing method provided in the embodiments of the present invention will be further described, such as... Figure 7 As shown, the method may specifically include the following steps:

[0336] Step S701: Sensing signal transmission.

[0337] Specifically, the sensing nodes send sensing signals to the target area.

[0338] Step S702: Receive the echo signal.

[0339] Specifically, the first sensing node receives the echo signal reflected by the target object itself, and the echo signal sent by the second node and reflected by the target object.

[0340] Step S703: Transmit the matrix representation of the received signals.

[0341] Specifically, the active sensing transmit signal matrix and receive signal matrix, as well as the passive sensing transmit signal matrix and receive signal matrix, are acquired.

[0342] As an example, the above steps S701-S703 can be performed by the signal transceiver module of the first sensing node.

[0343] Step S704: Based on frequency division, separate the echo y1 of itself and the echo signal y2 of the adjacent node.

[0344] Specifically, based on the different frequency bands of the echo signals, the first echo signal y1 and the second echo signal y2 are separated.

[0345] As an example, step S704 can be performed by the fusion signal separation module of the first sensing node.

[0346] For y1, execute steps S705-S706.

[0347] Step S705: Delete the transmitted data information.

[0348] Step S706: Extract the channel information matrix containing time delay and Doppler frequency shift.

[0349] For y2, execute steps S707-S708.

[0350] Step S707: Delete the transmitted data information.

[0351] Step S708: Extract the channel information matrix containing time delay and Doppler frequency shift.

[0352] Steps S705-S708 involve obtaining the channel information matrix in active sensing and passive sensing, and you can refer to the explanation in step S504 for details.

[0353] As an example, the above steps S705-S708 can be performed by the target perception information extraction module of the first perception node.

[0354] Step S709: Analysis of active and passive sensing time delay and Doppler frequency shift deviation.

[0355] Specifically, this involves acquiring time delay sensing information and frequency shift sensing information from both active and passive sensing. For details, please refer to the explanations of steps S505-S506 above.

[0356] Step S710: Obtain a vector containing TO, CFO, and active / passive perception bias through relevant algorithms.

[0357] This part can be found in the explanations of steps S507 and S509 above.

[0358] Step S711: Bias and TO-CFO estimation and registration.

[0359] During the process of bias and TO-CFO estimation and registration, in the case of a single objective, step S711a is executed, and in the case of a multi-objective objective, step S711b is executed.

[0360] Step S711a: Eliminate the biases between TO and CFO, as well as between active and passive perception, through relevant algorithms.

[0361] This section can be found in the explanations of steps S608-S611 and S613-S616 above.

[0362] Step S711b: Estimate the bias and the phase space of TO-CFO.

[0363] This part can be found in the explanations of steps S507 and S509 above.

[0364] Step S712: Achieve phase matching for active and passive sensing.

[0365] As an example, the above steps S709-S712 can be performed by the signal correlation processing module of the first sensing node.

[0366] This invention also provides an active-passive collaborative sensing device. Figure 8 This is a schematic diagram of the active-passive cooperative sensing device provided in an embodiment of the present invention, applied to the first sensing node, such as... Figure 8 As shown, the device includes:

[0367] The receiving module 801 is used to receive the echo signal reflected by the target object;

[0368] The first separation module 802 is used to separate a first echo signal and a second echo signal from the echo signal according to the frequency band of the echo signal; wherein the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node.

[0369] The first determining module 803 is used to determine the first target sensing information actively sensed based on the first echo modulation symbol and the first transmitted modulation symbol; wherein the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal;

[0370] The second determining module 804 is used to determine the passively sensed second target sensing information based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal;

[0371] The second separation module 805 is used to separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information;

[0372] The third separation module 806 is used to separate the second time delay sensing information and the second frequency shift sensing information from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift information includes carrier frequency deviation CFO;

[0373] The first processing module 807 is used to perform relevant processing on the first time delay perception information and the second time delay perception information to obtain time delay error perception information;

[0374] The second processing module 808 constructs a time delay error perception vector based on the first time delay perception information and the time delay error perception information, and performs relevant processing on the second time delay perception information and the time delay error perception vector to obtain the third time delay perception information; both the third time delay perception information and the first time delay perception information are used to obtain the distance information of the target object.

[0375] The third processing module 809 is used to perform correlation processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information;

[0376] The fourth processing module 810 constructs a frequency shift error sensing vector based on the first frequency shift sensing information and the frequency shift error sensing information, performs relevant processing on the second frequency shift sensing information and the frequency shift error sensing vector, and obtains the third frequency shift sensing information; both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

[0377] In one embodiment of the present invention, the number of target objects is multiple, and the device further includes:

[0378] The first operation module is used to perform an inverse discrete Fourier transform (IDFT) operation on the time delay error sensing information to obtain a time delay error phase information sequence.

[0379] The second operation module is used to perform an IDFT operation on the first time delay sensing information to obtain an actively sensed first time delay phase information sequence; each first time delay phase information corresponds to one target object;

[0380] The third operation module is used to perform IDFT operation on the second time delay sensing information to obtain a passively sensed second time delay phase information sequence; each second time delay phase information corresponds to one target object;

[0381] The third determining module is used to determine, for the first object among the target objects, the time delay error phase information, the first time delay phase information, and the second time delay phase information corresponding to the first object according to the first preset matching condition; the first preset matching condition is: the sum of the time delay error phase information and the first time delay phase information is equal to the second time delay phase information; the time delay error phase information, the first time delay phase information, and the second time delay phase information corresponding to the first object are used to obtain the distance information of the first object;

[0382] The fourth operation module is used to perform DFT operation on the frequency shift error sensing information to obtain a frequency shift error phase information sequence;

[0383] The fifth operation module is used to perform DFT operation on the first frequency shift sensing information to obtain an actively sensed first frequency shift phase information sequence; each first frequency shift phase information corresponds to one target object;

[0384] The sixth operation module is used to perform DFT operation on the second frequency shift sensing information to obtain a passively sensed first frequency shift phase information sequence; each second frequency shift phase information corresponds to one target object;

[0385] The fourth determining module is used to determine, for the first object among the target objects, the frequency shift error phase information, the first frequency shift phase information, and the second frequency shift phase information corresponding to the first object according to the second preset matching condition; the second preset matching condition is that the sum of the frequency shift error phase information and the first frequency shift phase information is equal to the second frequency shift phase information; the frequency shift error phase information, the first frequency shift phase information, and the second frequency shift phase information corresponding to the first object are used to obtain the velocity information of the first object.

[0386] In one embodiment of the present invention, the time delay error sensing information includes single-target time delay error sensing information and an interference term; the phase information in the single-target time delay error sensing information is the same on any two antennas; the frequency shift error sensing information includes single-target frequency shift error sensing information and an interference term; the phase information in the single-target frequency shift error sensing information is the same on any two antennas;

[0387] The first operation module is specifically used to perform an IDFT operation on the time delay error sensing information, obtain the index of the IDFT operation result at the peak, and obtain a sequence of phase information containing interference time delay error.

[0388] Extract the delay error phase information sequence corresponding to the single-target delay error sensing information from the interference-containing delay error phase information sequence;

[0389] The fourth operation module is specifically used to perform a DFT operation on the frequency shift error sensing information, obtain the index of the DFT operation result at the peak, and obtain a sequence of phase information containing interference frequency shift error.

[0390] Extract the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the interference-containing frequency shift error phase information sequence.

[0391] In one embodiment of the present invention, the device further includes:

[0392] The first operation module is specifically used to perform an IDFT operation on the time delay error sensing information, obtain the index of the IDFT operation result at the peak, and obtain a sequence of phase information containing interference time delay error.

[0393] Obtain the real part of the IDFT operation result corresponding to each phase information containing interference delay error, and obtain the delay IDFT result sequence;

[0394] For each time-delay IDFT result on the first antenna, calculate the first difference with the corresponding time-delay IDFT result on each of the second antennas in sequence;

[0395] If the first difference is greater than a preset threshold, the interference-containing delay error phase information corresponding to the delay IDFT result is deleted from the interference-containing delay error phase information sequence of the first antenna to obtain the delay error phase information sequence.

[0396] The fourth operation module is specifically used to perform a DFT operation on the frequency shift error sensing information, obtain the index of the DFT operation result at the peak, and obtain a sequence of phase information containing interference frequency shift error.

[0397] Obtain the real part of the DFT operation result corresponding to each phase information containing interference frequency shift error, and obtain the frequency shift DFT result sequence;

[0398] For each frequency shift DFT result on the first antenna, the second difference is calculated sequentially with the corresponding frequency shift DFT result on each of the second antennas;

[0399] If the second difference is greater than the preset threshold, the interference-containing frequency shift error phase information corresponding to the frequency shift DFT result is deleted from the interference-containing frequency shift error phase information sequence of the first antenna to obtain the frequency shift error phase information sequence.

[0400] In one embodiment of the present invention, the first sensing signal and the second sensing signal are orthogonal frequency division multiplexing (OFDM) signals.

[0401] The active-passive cooperative sensing device provided in this embodiment of the invention separates the first actively sensed echo signal and the second passively sensed echo signal from the echo signal according to the frequency band of the echo signal. It then determines the first actively sensed target sensing information and the second passively sensed target sensing information based on the echo signal and the sensing signal. From the first target sensing information, it separates the first actively sensed time delay sensing information and the first frequency shift sensing information, and from the second target sensing information, it separates the second passively sensed time delay sensing information and the second frequency shift sensing information. This enables separate processing of the time delay sensing information and frequency shift sensing information of the target object, simplifying the calculation. By performing correlation processing on the first and second time-delay sensing information, the time delay difference and TO in passive sensing are extracted, obtaining time delay error information and constructing a time delay error sensing vector. Then, correlation processing is performed on the second time-delay sensing information and the time delay error sensing vector to eliminate the time delay difference and TO from the second time-delay sensing information. Similarly, by performing correlation processing on the first and second frequency shift sensing information, the frequency shift difference and CFO in passive sensing are extracted, obtaining frequency shift error information and constructing a frequency shift error sensing vector. Then, correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to eliminate the frequency shift difference and CFO from the second frequency shift sensing information. By actively sensing to assist in eliminating the time delay difference, frequency shift difference, TO, and CFO in the target sensing information in passive sensing, the second echo signal is transformed from an interference signal into a useful signal, which can improve the signal-to-interference-plus-noise ratio of the echo signal received by the first sensing node, thereby improving sensing performance.

[0402] Furthermore, the active-passive cooperative sensing device provided in this embodiment of the invention achieves complete elimination of time delay difference, frequency shift difference, TO and CFO, without the need for further processing of time delay difference and frequency shift difference through geometric alignment, and has high processing efficiency.

[0403] Furthermore, the embodiments of the present invention are also applicable to scenarios where there are obstacles between the passive sensing transceivers, thus having a wide range of applications.

[0404] This invention also provides an electronic device, such as... Figure 9 As shown, it includes a processor 901, a communication interface 902, a memory 903, and a communication bus 904, wherein the processor 901, the communication interface 902, and the memory 903 communicate with each other through the communication bus 904.

[0405] Memory 903 is used to store computer programs;

[0406] When processor 901 executes a program stored in memory 903, it performs the following steps:

[0407] Receive the echo signal reflected by the target object;

[0408] Based on the frequency band of the echo signal, a first echo signal and a second echo signal are separated from the echo signal; wherein, the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node;

[0409] Based on the first echo modulation symbol and the first transmitted modulation symbol, the first target sensing information of active sensing is determined; wherein, the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal;

[0410] The second target sensing information is determined passively based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal.

[0411] Separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information;

[0412] The second time delay sensing information and the second frequency shift sensing information are separated from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift information includes carrier frequency deviation CFO;

[0413] The first and second time delay sensing information are processed to obtain time delay error sensing information;

[0414] A time delay error perception vector is constructed based on the first time delay perception information and the time delay error perception information. The second time delay perception information and the time delay error perception vector are then processed to obtain the third time delay perception information. Both the third time delay perception information and the first time delay perception information are used to obtain the distance information of the target object.

[0415] The first frequency shift sensing information and the second frequency shift sensing information are correlated to obtain frequency shift error sensing information;

[0416] A frequency shift error sensing vector is constructed based on the first frequency shift sensing information and the frequency shift error sensing information. Correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to obtain the third frequency shift sensing information. Both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

[0417] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0418] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0419] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0420] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0421] In another embodiment of the present invention, a computer-readable storage medium is also provided, which stores a computer program that, when executed by a processor, implements the steps of any of the above-described methods for automatically generating official documents.

[0422] In another embodiment of the present invention, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute any of the methods for automatically generating official documents described in the above embodiments.

[0423] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., solid state disk (SSD)).

[0424] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, 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. Without further limitations, 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 said element.

[0425] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the apparatus embodiments for the method of automatically generating official documents are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0426] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method for active and passive collaborative sensing, characterized in that, Applied to the first sensing node, the method includes: Receive the echo signal reflected by the target object; Based on the frequency band of the echo signal, a first echo signal and a second echo signal are separated from the echo signal; wherein, the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node; Based on the first echo modulation symbol and the first transmitted modulation symbol, the first target sensing information of active sensing is determined; wherein, the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal; The second target sensing information is determined passively based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal. Separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information; Separate second time delay sensing information and second frequency shift sensing information from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift sensing information includes carrier frequency deviation CFO; The first time delay perception information and the second time delay perception information are processed to obtain time delay error perception information; A delay error perception vector is constructed based on the first delay perception information and the delay error perception information. Correlation processing is performed on the second delay perception information and the delay error perception vector to obtain third delay perception information. Both the third delay perception information and the first delay perception information are used to obtain the distance information of the target object. The first frequency shift sensing information and the second frequency shift sensing information are subjected to correlation processing to obtain frequency shift error sensing information; A frequency shift error sensing vector is constructed based on the first frequency shift sensing information and the frequency shift error sensing information. Correlation processing is performed on the second frequency shift sensing information and the frequency shift error sensing vector to obtain third frequency shift sensing information. Both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

2. The method according to claim 1, characterized in that, The number of target objects is multiple; After performing correlation processing on the first delay sensing information and the second delay sensing information to obtain delay error sensing information, the method further includes: Perform an inverse discrete Fourier transform (IDFT) operation on the time delay error sensing information to obtain a time delay error phase information sequence; An IDFT operation is performed on the first time-delay sensing information to obtain an actively sensed first time-delay phase information sequence; each first time-delay phase information corresponds to one target object; An IDFT operation is performed on the second time-delay sensing information to obtain a passively sensed second time-delay phase information sequence; each second time-delay phase information corresponds to one target object; For the first object in the target objects, according to the first preset matching condition, the time delay error phase information, the first time delay phase information and the second time delay phase information corresponding to the first object are determined; the first preset matching condition is: the sum of the time delay error phase information and the first time delay phase information is equal to the second time delay phase information; the time delay error phase information, the first time delay phase information and the second time delay phase information corresponding to the first object are used to obtain the distance information of the first object; After performing correlation processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information, the method further includes: Perform a Discrete Fourier Transform (DFT) operation on the frequency shift error sensing information to obtain a frequency shift error phase information sequence; Perform a DFT operation on the first frequency shift sensing information to obtain an actively sensed first frequency shift phase information sequence; each first frequency shift phase information corresponds to one target object; Perform a DFT operation on the second frequency shift sensing information to obtain a passively sensed second frequency shift phase information sequence; each second frequency shift phase information corresponds to one target object; For the first object in the target objects, according to the second preset matching condition, the frequency shift error phase information, the first frequency shift phase information and the second frequency shift phase information corresponding to the first object are determined; the second preset matching condition is: the sum of the frequency shift error phase information and the first frequency shift phase information is equal to the second frequency shift phase information; the frequency shift error phase information, the first frequency shift phase information and the second frequency shift phase information corresponding to the first object are used to obtain the velocity information of the first object.

3. The method according to claim 2, characterized in that, The time delay error sensing information includes single-target time delay error sensing information and interference terms; the phase information in the single-target time delay error sensing information is the same on any two antennas; the frequency shift error sensing information includes single-target frequency shift error sensing information and interference terms; the phase information in the single-target frequency shift error sensing information is the same on any two antennas; The step of performing an IDFT operation on the time delay error information to obtain a time delay error phase information sequence includes: Perform an IDFT operation on the time delay error sensing information, obtain the index of the IDFT operation result at the peak, and obtain the phase information sequence of time delay error containing interference; Extract the delay error phase information sequence corresponding to the single-target delay error sensing information from the interference-containing delay error phase information sequence; The step of performing a DFT operation on the frequency shift error sensing information to obtain a frequency shift error phase information sequence includes: Perform a DFT operation on the frequency shift error sensing information, obtain the index of the DFT operation result at the peak, and obtain a sequence of frequency shift error phase information containing interference. Extract the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the interference-containing frequency shift error phase information sequence.

4. The method according to claim 3, characterized in that, The first sensing node includes a first antenna and one or more second antennas; After performing an IDFT operation on the time delay error sensing information, obtaining the index of the IDFT operation result at the peak, and obtaining the phase information sequence containing the interference time delay error, the method further includes: Obtain the real part of the IDFT operation result corresponding to each phase information containing interference delay error, and obtain the delay IDFT result sequence; The step of extracting the single-target time delay error phase information sequence corresponding to the target time delay error sensing information from the interference-containing time delay error phase information sequence includes: For each time-delay IDFT result on the first antenna, calculate the first difference with the corresponding time-delay IDFT result on each of the second antennas in sequence; If the first difference is greater than a preset threshold, the interference-containing delay error phase information corresponding to the delay IDFT result is deleted from the interference-containing delay error phase information sequence of the first antenna to obtain the delay error phase information sequence. After performing a DFT operation on the frequency shift error sensing information, obtaining the index of the DFT operation result at the peak, and obtaining the phase information sequence containing the interference frequency shift error, the method further includes: Obtain the real part of the DFT operation result corresponding to each phase information containing interference frequency shift error, and obtain the frequency shift DFT result sequence; The step of extracting the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the interference-containing frequency shift error phase information sequence includes: For each frequency shift DFT result on the first antenna, the second difference is calculated sequentially with the corresponding frequency shift DFT result on each of the second antennas; If the second difference is greater than the preset threshold, the interference-containing frequency shift error phase information corresponding to the frequency shift DFT result is deleted from the interference-containing frequency shift error phase information sequence of the first antenna to obtain the frequency shift error phase information sequence.

5. The method according to any one of claims 1-4, characterized in that, The first sensing signal and the second sensing signal are orthogonal frequency division multiplexing (OFDM) signals.

6. A combined active and passive sensing device, characterized in that, The device, applied to a first sensing node, includes: The receiving module is used to receive the echo signal reflected by the target object; The first separation module is used to separate a first echo signal and a second echo signal from the echo signal according to the frequency band of the echo signal; wherein the first echo signal is the echo signal of the first sensing signal, and the second echo signal is the echo signal of the second sensing signal; the first sensing signal is emitted by the first sensing node, and the second sensing signal is emitted by the second sensing node. The first determining module is used to determine the first target sensing information actively sensed based on the first echo modulation symbol and the first transmitted modulation symbol; wherein the first echo modulation symbol is determined based on the first echo signal, and the first transmitted modulation symbol is determined based on the first sensing signal; The second determining module is used to determine the passively sensed second target sensing information based on the second echo modulation symbol and the second transmitted modulation symbol; wherein the second echo modulation symbol is determined based on the second echo signal, and the second transmitted modulation symbol is determined based on the second sensing signal; The second separation module is used to separate the first time delay sensing information and the first frequency shift sensing information from the first target sensing information; The third separation module is used to separate the second time delay sensing information and the second frequency shift sensing information from the second target sensing information; the second time delay sensing information includes time deviation TO; the second frequency shift sensing information includes carrier frequency deviation CFO; The first processing module is used to perform relevant processing on the first time delay perception information and the second time delay perception information to obtain time delay error perception information; The second processing module is used to construct a delay error perception vector based on the first delay perception information and the delay error perception information, and to perform correlation processing on the second delay perception information and the delay error perception vector to obtain third delay perception information; both the third delay perception information and the first delay perception information are used to obtain the distance information of the target object; The third processing module is used to perform relevant processing on the first frequency shift sensing information and the second frequency shift sensing information to obtain frequency shift error sensing information; The fourth processing module is used to construct a frequency shift error sensing vector based on the first frequency shift sensing information and the frequency shift error sensing information, and to perform correlation processing on the second frequency shift sensing information and the frequency shift error sensing vector to obtain third frequency shift sensing information; both the third frequency shift sensing information and the first frequency shift sensing information are used to obtain the velocity information of the target object.

7. The apparatus according to claim 6, characterized in that, The number of target objects is multiple, and the device further includes: The first operation module is used to perform a Discrete Fourier Transform (IDFT) operation on the time delay error sensing information to obtain a time delay error phase information sequence. The second operation module is used to perform an IDFT operation on the first time delay sensing information to obtain an actively sensed first time delay phase information sequence; each first time delay phase information corresponds to one target object; The third operation module is used to perform IDFT operation on the second time delay sensing information to obtain a passively sensed second time delay phase information sequence; each second time delay phase information corresponds to one target object; The third determining module is used to determine, for the first object among the target objects, the time delay error phase information, the first time delay phase information, and the second time delay phase information corresponding to the first object according to the first preset matching condition; the first preset matching condition is: the sum of the time delay error phase information and the first time delay phase information is equal to the second time delay phase information; the time delay error phase information, the first time delay phase information, and the second time delay phase information corresponding to the first object are used to obtain the distance information of the first object; The fourth operation module is used to perform DFT operation on the frequency shift error sensing information to obtain a frequency shift error phase information sequence; The fifth operation module is used to perform DFT operation on the first frequency shift sensing information to obtain an actively sensed first frequency shift phase information sequence; each first frequency shift phase information corresponds to one target object; The sixth operation module is used to perform DFT operation on the second frequency shift sensing information to obtain a passively sensed second frequency shift phase information sequence; each second frequency shift phase information corresponds to one target object; The fourth determining module is used to determine, for the first object among the target objects, the frequency shift error phase information, the first frequency shift phase information, and the second frequency shift phase information corresponding to the first object according to the second preset matching condition; the second preset matching condition is that the sum of the frequency shift error phase information and the first frequency shift phase information is equal to the second frequency shift phase information; the frequency shift error phase information, the first frequency shift phase information, and the second frequency shift phase information corresponding to the first object are used to obtain the velocity information of the first object.

8. The apparatus according to claim 7, characterized in that, The time delay error sensing information includes single-target time delay error sensing information and interference terms; the phase information in the single-target time delay error sensing information is the same on any two antennas; the frequency shift error sensing information includes single-target frequency shift error sensing information and interference terms; the phase information in the single-target frequency shift error sensing information is the same on any two antennas; The first operation module is specifically used to perform an IDFT operation on the time delay error sensing information, obtain the index of the IDFT operation result at the peak, and obtain a sequence of phase information containing interference time delay error. Extract the delay error phase information sequence corresponding to the single-target delay error sensing information from the interference-containing delay error phase information sequence; The fourth operation module is specifically used to perform a DFT operation on the frequency shift error sensing information, obtain the index of the DFT operation result at the peak, and obtain a sequence of phase information containing interference frequency shift error. Extract the frequency shift error phase information sequence corresponding to the single-target frequency shift error sensing information from the interference-containing frequency shift error phase information sequence.

9. An electronic device, characterized in that, It includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the steps of the method according to any one of claims 1-5.

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 steps of the method described in any one of claims 1-5.

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