Multi-static radar system and method, apparatus and storage medium for detecting

Abstract

The application provides a multi-static radar system and a detection method, device and storage medium thereof, and relates to the technical field of radars.The multi-static radar system comprises a plurality of signal transmitting ends with reconfigurable holographic super surfaces and a plurality of signal receiving ends with reconfigurable holographic super surfaces.The method comprises the following steps: obtaining a receiving signal of the signal receiving end according to a transmitting signal of the signal transmitting end, an amplitude matrix of the signal transmitting end and an amplitude matrix of the signal receiving end; constructing a target function according to the receiving signal, wherein the target function represents a probability that the signal receiving end detects a target object; and solving an optimization problem of the target function, and detecting the target object by the multi-static radar system in the case that the optimization problem has an optimal solution.The application can improve the target detection probability of the multi-static radar and realize high-accuracy target detection.

Description

Technical Field

[0001] This invention relates to the field of radar technology, and in particular to a multistatic radar system and its detection method, apparatus and storage medium. Background Technology

[0002] Radar is a system that uses electromagnetic waves to sense targets. Because it is not easily affected by adverse weather and lighting conditions, it is widely used in various applications such as navigation and positioning.

[0003] Multistatic radar refers to a type of radar that includes multiple transmitting or receiving antennas located at different geographical locations. These antennas can simultaneously observe a radar target from different angles, thus obtaining more information about the radar target compared to monostatic radar, and achieving higher performance in detection, classification, and other areas.

[0004] In multistatic radars, phased arrays are widely used as antennas to enhance signal gain. Multiple phased array antennas are used to transmit and receive radar signals, thereby enabling target detection. However, due to the high power consumption of hardware components such as phase shifters and power dividers that phased arrays rely on, the detection accuracy of phased array radars is quite limited under given power consumption constraints. Summary of the Invention

[0005] In view of this, the purpose of this invention is to provide a multistatic radar system and its detection method, device and storage medium. This invention can specifically solve the problem of low radar accuracy caused by the use of phased array in existing multistatic radars.

[0006] Based on the above objectives, in a first aspect, the present invention proposes a detection method for a multistatic radar system. The multistatic radar system includes multiple signal transmitters with reconfigurable holographic metasurfaces and multiple signal receivers with reconfigurable holographic metasurfaces. The method includes: obtaining a received signal from the signal receiver based on the transmitted signal from the signal transmitter, the amplitude matrix of the signal transmitter, and the amplitude matrix of the signal receiver; constructing an objective function based on the received signal, the objective function representing the probability that the signal receiver detects a target; solving an optimization problem of the objective function; and, if the optimization problem has an optimal solution, detecting the target using the multistatic radar system.

[0007] Optionally, the received signal of the signal receiving end The expression is:

[0008]

[0009] Where E is the total energy of the transmitted signal. Refers to the mtht The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the target reflection coefficient of the holographic metasurface. and They are respectively the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the propagation matrix in the holographic metasurface. For the mth r Each receiver can reconstruct the amplitude matrix of the holographic metasurface. and Refers to the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the guiding vector of the holographic metasurface. For the mth t The amplitude matrix of the holographic metasurface can be reconstructed at each emitter. In order to transmit signals, Refers to the mth r Each receiver can reconstruct the Gaussian white noise signal received at the radiating unit of the holographic metasurface.

[0010] Optionally, after obtaining the signal representation of the signal receiving end and before constructing the objective function based on the received signal, the method further includes: matching a filter for each signal receiving end, the filter being associated with the transmitted signal received by the signal receiving end; filtering the received signal based on the filter to obtain the transmitted signal associated with the current filter.

[0011] Optionally, constructing the target function based on the received signal includes: acquiring a first function and a second function of the received signal, wherein the first function is generated under a first condition and the second function is generated under a second condition, and the first condition and the second condition are opposite conditions; obtaining the log-likelihood ratio of the first function and the second function based on the first function and the second function; and obtaining the target function based on the probability of the second condition occurring when the log-likelihood ratio is greater than a preset value.

[0012] Optionally, after obtaining the objective function, the method further includes: taking the probability of the first condition occurring when the log-likelihood ratio is greater than a preset value as the false detection probability of the multi-static radar system.

[0013] Optionally, solving the optimization problem of the objective function includes: determining the optimization problem according to preset constraints, and solving the optimal solution of the optimization problem; wherein the preset constraints include the false detection probability being equal to a preset probability, the signal transmission power of each transmitter being a preset power, the amplitude matrix of the signal transmitter, and the amplitude matrix of the signal receiver.

[0014] Secondly, a detection device for a multistatic radar system is also provided. The multistatic radar system includes multiple signal transmitters with reconfigurable holographic metasurfaces and multiple signal receivers with reconfigurable holographic metasurfaces. The device includes: a signal processing module for obtaining a received signal from the signal receiver based on the transmitted signal from the signal transmitter, the amplitude matrix of the signal transmitter, and the amplitude matrix of the signal receiver; a function construction module for constructing an objective function based on the received signal, the objective function representing the probability that the signal receiver detects a target; and a detection module for solving an optimization problem of the objective function, and detecting the target through the multistatic radar system when the optimization problem has an optimal solution.

[0015] Thirdly, a computer-readable storage medium is also provided, having a computer program stored thereon, the program being executed by a processor to implement the method described in any of the first aspects.

[0016] Fourthly, a multistatic radar system is also provided, characterized in that the multistatic radar system includes: one or more processors; a memory for storing one or more programs; a radar module for detecting targets within a target space; and when the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any of the first aspects.

[0017] Optionally, the radar module includes multiple signal transmitting ends with reconfigurable holographic metasurfaces and multiple signal receiving ends with reconfigurable holographic metasurfaces. The signal transmitting end includes multiple sets of one-to-one corresponding transmitters and a first reconfigurable holographic metasurface. The transmitter is used to transmit radar signals, which are transmitted to the target space via the first reconfigurable holographic metasurface. The signal receiving end includes multiple sets of one-to-one corresponding second reconfigurable holographic metasurfaces and receivers. The second reconfigurable holographic metasurface is used to receive reflected signals from the target space and transmit them to the receiver.

[0018] In summary, the present invention has at least the following beneficial effects:

[0019] This embodiment provides a detection method for a multistatic radar system. Both the signal transmitter and receiver employ reconfigurable holographic metasurfaces, which can reduce system costs. The received signal is obtained from the transmitted signal, the amplitude matrix of the transmitter, and the amplitude matrix of the receiver. A target function representing the probability of target detection by the receiver is then constructed based on the received signal. When the target function has an optimal solution, the multistatic radar system can improve the target detection probability and achieve high-accuracy target detection. Attached Figure Description

[0020] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in the invention and should not be construed as limiting the scope of the invention.

[0021] Figure 1 This diagram illustrates the structure of a multi-static radar system according to the present invention.

[0022] Figure 2 A schematic diagram of the reconfigurable holographic metasurface RHS according to an embodiment of the present invention is shown;

[0023] Figure 3 This invention illustrates a flowchart of the detection method for a multi-static radar system according to the present invention.

[0024] Figure 4 A schematic diagram of the structure of a detection device for a multi-static radar system according to an embodiment of the present invention is shown;

[0025] Figure 5 A schematic diagram of a multi-base radar system provided by some embodiments of the present invention is shown;

[0026] Figure 6 A schematic diagram of a storage medium provided in an embodiment of the present invention is shown. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0028] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0029] Figure 1 A schematic diagram of the structure of a multi-base radar system according to the present invention is shown.

[0030] In this embodiment, the multi-static radar system includes multiple signal transmitters with reconfigurable holographic surfaces (RHS) and multiple signal receivers with reconfigurable holographic surfaces. Each signal transmitter includes multiple sets of one-to-one corresponding transmitters and a first reconfigurable holographic surface transmitter for transmitting radar signals, which are then transmitted to the target space via the first reconfigurable holographic surface. For example... Figure 1 The first transmitter is connected to the first transmission RHS, the second transmitter is connected to the second transmission RHS... and so on. t The transmitter is connected to the mth t Launch RHS.

[0031] In this embodiment, the radar signal transmitted into the target space via the first reconfigurable holographic metasurface is reflected by the radar target object to be detected within the target space and then received by the signal receiver. The signal receiver includes multiple sets of one-to-one corresponding second reconfigurable holographic metasurfaces and receivers. The second reconfigurable holographic metasurfaces are used to receive the transmitted signal from the target space and transmit it to the receiver. Figure 1 The first receiver is connected to the first receiving RHS, the second receiver is connected to the second receiving RHS, and so on down to the mth receiver. r The receiver is connected to the mth r Receive RHS. (Reference) Figure 1 In this embodiment, all transmitters and receivers are interconnected.

[0032] Figure 2 This diagram illustrates the structure of the reconfigurable holographic metasurface RHS in this embodiment. (Refer to...) Figure 2 In this embodiment, each transmitting RHS has N t There are N radiating elements, and each receiving RHS has N r Each RHS consists of a waveguide, a feed source, and an array of metamaterial elements. When transmitting radar signals via the RHS, the radar signal is first fed into the waveguide through the feed source and then propagates to the metamaterial elements embedded in the waveguide. Each metamaterial element radiates signal energy into free space in the form of a leakage wave. The radiation amplitude of the electromagnetic wave at each metamaterial element can be independently controlled by adjusting the bias voltage on the element. Specifically, each metamaterial element is controlled by the switching states of multiple PIN diodes. Assuming that one element is controlled by I PIN diodes, then the element has 2 IEach metamaterial unit has an adjustable discrete amplitude value. By designing the amplitude value at each metamaterial unit, the desired waveform can be obtained. The process of receiving the RHS signal is the reverse of the process of transmitting the RHS signal. After receiving the radar signal, each metamaterial unit receiving the RHS signal transmits the received radar signal to the waveguide receiving the RHS signal. The waveguide then transmits the signal to the feed source receiving the RHS signal, and finally sends it to the receiver corresponding to the RHS signal.

[0033] The multistatic radar system in this embodiment uses RHS, which eliminates the need for hardware components such as phase shifters and power dividers that phased arrays rely on, thus greatly reducing system cost and power consumption.

[0034] Figure 3 A flowchart illustrating the steps of a detection method for a multi-static radar system according to the present invention is shown. (Reference) Figure 3 The detection method of a multi-static radar system includes the following steps S301 to S303:

[0035] S301. Based on the transmitted signal from the signal transmitter, the amplitude matrix of the signal transmitter, and the amplitude matrix of the signal receiver, obtain the received signal from the signal receiver.

[0036] In this embodiment, let the m-th... t The transmission signal of each transmitter is Signals from different transmitters are orthogonal. The product of two orthogonal vectors is equal to zero. Therefore, when m ≠ m′,

[0037] In this embodiment, the amplitude matrix of the signal transmitter is the m-th... t The amplitude matrix of each transmitter RHS is as follows ψ t Let m be the signal radiation matrix of a single metamaterial unit at the transmitting end RHS, and m be the amplitude matrix at the receiving end. r The amplitude matrix of the RHS at each receiver is as follows ψ r This is the signal radiation matrix of a single metamaterial unit at the receiver RHS.

[0038] The received signal at the signal receiving end The expression is:

[0039]

[0040] Where E is the total energy of the transmitted signal. Refers to the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the target reflection coefficient of the holographic metasurface. and They are respectively the mtht The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the propagation matrix in the holographic metasurface. For the mth r Each receiver can reconstruct the amplitude matrix of the holographic metasurface. and Refers to the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the guiding vector of the holographic metasurface. For the mth t The amplitude matrix of the holographic metasurface can be reconstructed at each emitter. In order to transmit signals, Refers to the mth r Each receiver can reconstruct the Gaussian white noise signal received at the radiating unit of the holographic metasurface, and The mean is 0 and the variance is σ. 2 .

[0041] In this embodiment, according to the central limit theorem, It approximately follows a Gaussian distribution with a mean of 0 and a variance of 1.

[0042] It is understandable that when using phased array antennas, the detection accuracy of phased array radar is quite limited given the high power consumption of hardware components such as phase shifters and power dividers. In this embodiment, the radiated power of each transmitter can be expressed as: Where tr() represents the trace of the matrix. for The transpose matrix. For example, when the radiated power of each transmitter is 1, i.e.

[0043] In this embodiment, in order to reduce noise in the received signal, after obtaining the signal representation of the signal receiver and before constructing the objective function based on the received signal, the embodiment further includes: matching a filter for each signal receiver, filtering the received signal received by the signal receiver based on the filter, and obtaining the transmitted signal associated with the current filter.

[0044] In this embodiment, the filtered received signal It can be represented as: Indicates that by transmitting the signal The corresponding filter for the received signal Perform filtering to extract and The corresponding transmitted signal.

[0045] Since the transmitted signals of different RHSs are orthogonal and each transmitted signal is different, the received signal contains the transmitted signals of multiple transmitters. In order for each signal receiver to both receive different transmitted signals and distinguish between them, in this embodiment, a signal receiver can be matched with multiple filters simultaneously. For example, the first filter, the second filter, and the third filter are associated with transmitted signal A, transmitted signal B, and transmitted signal C, respectively. When the received signal includes transmitted signal B and transmitted signal C, the signal receiver extracts the corresponding transmitted signal B through the second filter and extracts the corresponding transmitted signal C through the third filter.

[0046] S302. Construct a target function based on the received signal. The target function represents the probability that the signal receiver detects the target object.

[0047] In this embodiment, constructing a target function based on the received signal includes: obtaining a first function and a second function of the received signal; obtaining the log-likelihood ratio of the first function and the second function based on the first function and the second function; and obtaining the target function based on the probability of a second condition occurring when the log-likelihood ratio is greater than a preset value.

[0048] The first function is generated under the first condition, and the second function is generated under the second condition. The first and second conditions are opposites of each other. For example, if the first condition H0 is that the target object does not exist within the target control, and the second condition H1 is that the target object exists within the target control, then the first function is:

[0049]

[0050] The second function is:

[0051]

[0052] Where A1 is the normalized coefficient corresponding to the first function, A2 is the normalized coefficient corresponding to the second function, and M... r m is the total number of receivers. r For the mth r One receiver, For the mth r The signal received by the receiver Let E be the variance and E be the total energy of the transmitted signal.

[0053] In this embodiment, the log-likelihood ratio of the first function and the second function is T = log(p(y|H1) / p(y|H0)), with a preset value of δ. When T > δ, the second condition H1 is considered to be true; otherwise, the first condition H0 is considered to be true. When the second condition is true, it indicates a higher probability of detecting the target object. Increasing the probability of the second condition being true can improve the detection accuracy.

[0054] In this embodiment, based on the probability of the second condition occurring when the log-likelihood ratio is greater than a preset value, the objective function is obtained as p. d =p(T>δ|H1), the objective function can represent the probability of detecting the target object. When the probability reaches its maximum value, the detection accuracy can be improved.

[0055] It is understandable that in practical applications, detection using a multistatic radar system involves a probability of false detection. Furthermore, according to the Neyman-Pearson criterion, by pre-determining the risk probability of one type of error based on the importance of the two types of errors to the test results, an appropriate discrimination boundary can be determined to minimize the impact of statistical test results on decision-making errors in production and scientific research. Therefore, in this embodiment, after obtaining the objective function, the false detection probability is also obtained. Specifically, the probability of the first condition occurring when the log-likelihood ratio is greater than a preset value is taken as the false detection probability of the multistatic radar system, where p is the false detection probability. f It can be calculated using the following formula: p f =p(T>δ|H0). The false positive probability can be used as an optimization parameter when finding the optimal solution to the objective function.

[0056] S303. Solve the optimization problem of the objective function. If the optimization problem has an optimal solution, detect the target object using a multi-static radar system.

[0057] Understandably, the essence of an optimization problem is to select a set of variables or parameters to achieve the optimal value of the design objective under a series of relevant constraints. In other words, the objective of an optimization problem is to maximize the detection probability of the objective function under given constraints. When the objective function is maximized, the multistatic radar system has the maximum detection probability, enabling it to accurately detect targets and thus ensuring its detection accuracy. Compared to phased array antennas, this embodiment can improve the detection probability at a given power.

[0058] Therefore, in order to maximize the detection probability of the objective function, this embodiment, after constructing the objective function based on the received signal, further includes: determining the optimization problem based on preset constraints and solving the optimal solution of the optimization problem; wherein, the preset constraints include the false detection probability being equal to the preset probability, the signal transmission power of each transmitter being the preset power, and the vectors of the amplitude matrix of the signal transmitter and the amplitude matrix of the signal receiver satisfying preset values.

[0059] In this embodiment, the objective of optimizing the objective function is to maximize the detection probability given a false detection probability. Specifically, when the false detection probability equals a preset probability, the false detection probability constraint is:

[0060] stp f=γ

[0061] Where γ is the preset probability, st is the subject to, and stp is the target probability. f =γ represents p f Condition p needs to be satisfied f =γ.

[0062] When the signal transmission power of each transmitter is at a preset power, the power constraint condition is:

[0063]

[0064] in, Indicates the m-th t The preset power value of each transmitter, for example...

[0065] When the vectors of the amplitude matrix at the signal transmitter and the amplitude matrix at the signal receiver satisfy a preset value, the matrix constraint condition is:

[0066]

[0067] in and Representing vectors respectively and The nth element.

[0068] Based on the above constraints on false detection probability, power, and matrix, the optimization problem is determined. The optimization problem can be solved by iterative optimization to obtain the optimal solution. When the optimization problem has an optimal solution, the maximum detection probability of the objective function can be obtained under a series of relevant constraints.

[0069] The above method is a detection method for a multistatic radar system provided in this embodiment. Both the signal transmitter and the signal receiver employ reconfigurable holographic metasurfaces, which can reduce system costs. The received signal is obtained from the transmitted signal, the amplitude matrix of the transmitter, and the amplitude matrix of the receiver. Then, an objective function representing the probability of the receiver detecting a target is constructed based on the received signal. An optimization problem of the objective function is solved. When the optimization problem has an optimal solution, the multistatic radar system can improve the target detection probability and achieve high-accuracy target detection.

[0070] The application provides a detection device for a multistatic radar system, which is used to execute the detection method for a multistatic radar system described in the above embodiments, such as... Figure 4 As shown, the detection device 400 of the multi-base radar system includes:

[0071] The signal processing module 401 is used to obtain the received signal of the signal receiving end based on the transmitted signal of the signal transmitting end, the amplitude matrix of the signal transmitting end, and the amplitude matrix of the signal receiving end.

[0072] Function construction module 402 is used to construct a target function based on the received signal, wherein the target function characterizes the probability that the signal receiving end detects the target object;

[0073] The detection module 403 is used to solve the optimization problem of the objective function, and to detect the target object through a multi-static radar system when the optimal solution of the optimization problem is obtained.

[0074] In a feasible example, the signal receiver receives the signal. The expression is:

[0075]

[0076] Where E is the total energy of the transmitted signal. Refers to the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the target reflection coefficient of the holographic metasurface. and They are respectively the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the propagation matrix in the holographic metasurface. For the mth r Each receiver can reconstruct the amplitude matrix of the holographic metasurface. and Refers to the mth t The emitter can reconfigurate the holographic metasurface and the m-th... r Each receiver can reconstruct the guiding vector of the holographic metasurface. For the mth t The amplitude matrix of the holographic metasurface can be reconstructed at each emitter. In order to transmit signals, Refers to the mth r Each receiver can reconstruct the Gaussian white noise signal received at the radiating unit of the holographic metasurface.

[0077] In one feasible example, the signal processing module 401 is configured to, after obtaining the signal representation of the signal receiver, and before constructing an objective function based on the received signal, match a filter for each signal receiver, the filter being correlated with the transmitted signal received by the signal receiver; and filter the received signal received by the signal receiver based on the filter.

[0078] In a feasible example, the function construction module 402 is used to obtain a first function and a second function of the received signal, wherein the first function is generated under a first condition and the second function is generated under a second condition, and the first condition and the second condition are opposite conditions to each other; based on the first function and the second function, the log-likelihood ratio of the first function and the second function is obtained; based on the probability of the second condition occurring when the log-likelihood ratio is greater than a preset value, the target function is obtained.

[0079] In a feasible example, the function construction module 402 is further configured to, after obtaining the objective function, use the probability of the first condition occurring when the log-likelihood ratio is greater than a preset value as the false detection probability of the multi-static radar system.

[0080] In a feasible example, the function construction module 402 is also used to determine the optimization problem according to preset constraints and solve the optimal solution of the optimization problem; wherein, the preset constraints include the false detection probability being equal to a preset probability, the signal transmission power of each transmitter being a preset power, the amplitude matrix of the signal transmitter and the amplitude matrix of the signal receiver.

[0081] The detection device for the multistatic radar system provided in the above embodiments of the present invention and the detection method for the multistatic radar system provided in the embodiments of the present invention are based on the same inventive concept and have the same beneficial effects as the methods adopted, run or implemented by the application programs stored therein.

[0082] This embodiment provides a multistatic radar system, which includes: one or more processors; a memory for storing one or more programs; and a radar module for detecting targets within a target space. When one or more programs are executed by one or more processors, the one or more processors implement the detection method of the multistatic radar system.

[0083] Please refer to Figure 5 This illustrates another schematic diagram of a multistatic radar system provided by some embodiments of the present invention. For example... Figure 5 As shown, the multistatic radar system 20 includes: a processor 200, a memory 201, a bus 202, a communication interface 203, and a radar module 204. The processor 200, the communication interface 203, and the memory 201 are connected via the bus 202. The memory 201 stores a computer program that can run on the processor 200. When the processor 200 runs the computer program, it executes the detection method of the multistatic radar system provided in any of the foregoing embodiments of the present invention.

[0084] The memory 201 may include high-speed random access memory (RAM) or non-volatile memory, such as at least one disk storage device. Communication between this system network element and at least one other network element is achieved through at least one communication interface 203 (which can be wired or wireless), such as the Internet, wide area network, local area network, or metropolitan area network.

[0085] Bus 202 can be an ISA bus, PCI bus, or EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. Memory 201 is used to store programs. After receiving an execution instruction, processor 200 executes the program. The detection method of the multi-static radar system disclosed in any of the foregoing embodiments of the present invention can be applied to processor 200, or implemented by processor 200.

[0086] The processor 200 may be an integrated circuit chip with signal processing capabilities. In implementation, each step of the above method can be completed by the integrated logic circuitry in the hardware of the processor 200 or by instructions in software form. The processor 200 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this invention. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this invention can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules may reside in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory 201. The processor 200 reads the information in memory 201 and, in conjunction with its hardware, completes the steps of the above method.

[0087] In this embodiment, the radar module 204 includes multiple signal transmitting ends with reconfigurable holographic metasurfaces and multiple signal receiving ends with reconfigurable holographic metasurfaces. Each signal transmitting end includes multiple sets of one-to-one corresponding transmitters and a first reconfigurable holographic metasurface. The transmitters are used to transmit radar signals, which are then transmitted to the target space via the first reconfigurable holographic metasurface. Each signal receiving end includes multiple sets of one-to-one corresponding second reconfigurable holographic metasurfaces and receivers. The second reconfigurable holographic metasurfaces are used to receive reflected signals from the target space and transmit them to the receivers. Specifically, the structure of the radar module 204 is as follows: Figure 1 and Figure 2 The structure shown.

[0088] This invention also provides a computer-readable storage medium corresponding to the detection method of the multistatic radar system provided in the foregoing embodiments. Please refer to [link / reference]. Figure 6 The computer-readable storage medium shown is an optical disc 30, on which a computer program (i.e., a program product) is stored. When the computer program is run by a processor, it executes the detection method of the multi-static radar system provided in any of the foregoing embodiments.

[0089] It should be noted that examples of the computer-readable storage medium may also include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical and magnetic storage media, which will not be elaborated here.

[0090] The computer-readable storage medium provided in the above embodiments of the present invention and the detection method of the multi-static radar system provided in the embodiments of the present invention are based on the same inventive concept and have the same beneficial effects as the methods adopted, run or implemented by the application programs stored therein.

[0091] It should be noted that:

[0092] The algorithms and displays provided herein are not inherently related to any particular computer, virtual system, or other device. Various general-purpose systems can also be used in conjunction with the teachings herein. The required structure for constructing such systems is apparent from the above description. Furthermore, this invention is not directed to any particular programming language. It should be understood that the contents of the invention described herein can be implemented using various programming languages, and the above description of specific languages ​​is for the purpose of disclosing the best mode of implementation of the invention.

[0093] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0094] Similarly, it should be understood that, in order to simplify the invention and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this disclosure should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0095] Those skilled in the art will understand that modules in the device of the embodiments can be adaptively changed and placed in one or more devices different from that embodiment. Modules, units, or components in the embodiments can be combined into a single module, unit, or component, and further, they can be divided into multiple sub-modules, sub-units, or sub-components. Except where at least some of such features and / or processes or units are mutually exclusive, any combination can be used to combine all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or units of any method or device so disclosed. Unless expressly stated otherwise, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature that serves the same, equivalent, or similar purpose.

[0096] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the following claims, any of the claimed embodiments can be used in any combination.

[0097] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some or all of the components in the virtual machine creation system according to embodiments of the present invention. The present invention can also be implemented as a device or system program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0098] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several systems, several of these systems may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0099] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in the present invention, and these should all be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A detection method for a multi-static radar system, characterized in that, The multistatic radar system includes multiple signal transmitters with reconfigurable holographic metasurfaces and multiple signal receivers with reconfigurable holographic metasurfaces; the method includes: The received signal of the signal receiving end is obtained based on the transmitted signal of the signal transmitting end, the amplitude matrix of the signal transmitting end, and the amplitude matrix of the signal receiving end. A target function is constructed based on the received signal, and the target function characterizes the probability that the signal receiver detects the target object. Solve the optimization problem of the objective function, and when the optimization problem has an optimal solution, detect the target object through the multi-static radar system; Among them, the transmitted signals from multiple signal transmitters are orthogonal; the amplitude matrix of the signal transmitter is the first... The amplitude matrix of each transmitter RHS is as follows , The signal radiation matrix of a single metamaterial unit at the transmitting end RHS is given by the amplitude matrix at the receiving end. The amplitude matrix of each receiver RHS is as follows , This is the signal radiation matrix of a single metamaterial unit at the receiver RHS.

2. The method according to claim 1, characterized in that, The received signal of the signal receiving end The expression is: in, The total energy of the transmitted signal. Refers to the corresponding number The emitter can reconfigurable holographic metasurface and the first... Each receiver can reconstruct the target reflection coefficient of the holographic metasurface. and They are the first The emitter can reconfigurable holographic metasurface and the first... Each receiver can reconstruct the propagation matrix in the holographic metasurface. For the first Each receiver can reconstruct the amplitude matrix of the holographic metasurface. and They refer to the first The emitter can reconfigurable holographic metasurface and the first... Each receiver can reconstruct the guiding vector of the holographic metasurface. For the first The amplitude matrix of the holographic metasurface can be reconstructed at each emitter. In order to transmit signals, Refers to the first Each receiver can reconstruct the Gaussian white noise signal received at the radiating unit of the holographic metasurface.

3. The method according to claim 1, characterized in that, After obtaining the signal representation from the signal receiver but before constructing the objective function based on the received signal, the method further includes: A matching filter is provided for each signal receiver, and the filter is associated with the transmitted signal received by the signal receiver. The received signal is filtered according to the filter to obtain the transmitted signal associated with the current filter.

4. The method according to claim 1, characterized in that, The step of constructing the target function based on the received signal includes: A first function and a second function are used to acquire the received signal. The first function is generated under a first condition, and the second function is generated under a second condition. The first condition and the second condition are opposite conditions to each other. Based on the first function and the second function, the log-likelihood ratio of the first function and the second function is obtained; The objective function is obtained based on the probability of the second condition occurring when the log-likelihood ratio is greater than a preset value.

5. The method according to claim 4, characterized in that, After obtaining the objective function, the method further includes: The probability of the first condition occurring when the log-likelihood ratio is greater than a preset value is taken as the false detection probability of the multi-static radar system.

6. The method according to claim 5, characterized in that, The optimization problem of solving the objective function includes: determining the optimization problem according to preset constraints, and solving the optimal solution of the optimization problem; The preset constraints include the false detection probability being equal to a preset probability, the signal transmission power of each transmitter being a preset power, the amplitude matrix of the signal transmitter, and the amplitude matrix of the signal receiver.

7. A detection device for a multi-static radar system, characterized in that, The multi-static radar system includes multiple signal transmitters with reconfigurable holographic metasurfaces and multiple signal receivers with reconfigurable holographic metasurfaces. The device includes: The signal processing module is used to obtain the received signal of the signal receiving end based on the transmitted signal of the signal transmitting end, the amplitude matrix of the signal transmitting end, and the amplitude matrix of the signal receiving end. A function construction module is used to construct a target function based on the received signal, wherein the target function characterizes the probability that the signal receiving end detects the target object; The detection module is used to solve the optimization problem of the objective function, and when the optimization problem has an optimal solution, it detects the target object through the multi-static radar system. Among them, the transmitted signals from multiple signal transmitters are orthogonal; the amplitude matrix of the signal transmitter is the first... The amplitude matrix of each transmitter RHS is as follows , The signal radiation matrix of a single metamaterial unit at the transmitting end RHS is given by the amplitude matrix at the receiving end. The amplitude matrix of the RHS at each receiver is as follows , This is the signal radiation matrix of a single metamaterial unit at the receiver RHS.

8. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by a processor to implement the method as described in any one of claims 1-6.

9. A multi-static radar system, characterized in that, The multi-static radar system includes: One or more processors; Memory, used to store one or more programs; Radar module, used to detect targets within the target space; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in claims 1-6.

10. A multi-static radar system according to claim 9, characterized in that, The radar module includes multiple signal transmitters with reconfigurable holographic metasurfaces and multiple signal receivers with reconfigurable holographic metasurfaces. The signal transmitting end includes multiple sets of one-to-one corresponding transmitters and a first reconfigurable holographic metasurface. The transmitters are used to transmit radar signals, which are then transmitted to the target space via the first reconfigurable holographic metasurface. The signal receiving end includes multiple sets of one-to-one corresponding second reconfigurable holographic metasurfaces and receivers. The second reconfigurable holographic metasurfaces are used to receive reflected signals from the target space and transmit them to the receivers.

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