Mode configuration and position deployment method of RIS auxiliary radar system

Abstract

This invention discloses a method for mode configuration and location deployment of a RIS-assisted radar system, comprising: First, determining the corresponding receive signal-to-noise ratio (RSNR) algorithm for the radar system based on the characteristic parameters and locations of the radar, target, and RIS in the RIS-assisted radar system. Then, using the corresponding RSNR algorithm, calculating the RSNR of the RIS-assisted radar system under different configuration modes and / or different locations. Finally, comparing all calculated RSNR values, selecting the configuration mode and / or deployment location corresponding to the highest RSNR, and configuring the configuration mode of the RIS-assisted radar system and / or the location of the RIS deployment, thereby achieving the goal of improving radar detection performance with excellent cost-effectiveness.

Description

Technical Field

[0001] This invention relates to the field of positioning or presence detection technology using the reflection or re-radiation of radio waves, and specifically to a method for mode configuration and location deployment of a RIS-assisted radar system. Background Technology

[0002] In 2019, the Singapore University of Technology and Design (SUT / DI) improved the energy efficiency of a RIS-assisted multi-user MIMO system downlink by optimizing the RIS phase; further considering indoor applications, they utilized deep neural networks to optimize the RIS phase. In 2021, the European Telecommunications Institute (ETI) addressed the issue of large-scale IoT device access by using RIS to improve system performance and data rate. The University of Derich-Alexander in Germany applied RIS to millimeter-wave massive MIMO systems. Furthermore, from 2020 to 2024, Chalmers University of Technology in Sweden, the University of Oulu in Finland, and the University of Southampton in the UK conducted research on RIS-assisted positioning. However, existing research primarily focuses on optimizing the performance of wireless communication systems, with limited research on using RIS to enhance the detection capabilities of radar systems.

[0003] In 2021, the Air Force Early Warning Academy of the Chinese People's Liberation Army and the University of Sino, Italy, proposed the concept of RIS-assisted radar. The University of Naples Federico II, Italy, used RIS as a far-field reflector to extend the radar's scanning field of view and proposed a location deployment method. In 2022, the University of Sino, Italy, proposed a general RIS-assisted architecture for monostation or bistation radars, where the radar's transmitting and receiving antenna arrays utilize RIS deployed nearby to illuminate and observe targets.

[0004] The aforementioned deployment mode for RIS-assisted radar utilizes indirect echoes to modify the radar's field of view. As long as the radar system deployment scheme is chosen appropriately, it can compensate for the additional path loss in the radar-RIS link, aligning and merging the indirect and direct echoes provided by the RIS. This not only improves radar detection performance but also offers excellent cost-effectiveness. Therefore, a technology for the rational deployment of RIS-assisted radar is urgently needed. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention proposes a mode configuration and location deployment method for a RIS-assisted radar system, which can improve radar detection performance with excellent cost-effectiveness. The specific technical solution is as follows:

[0006] In a first aspect, a mode configuration method for a RIS-assisted radar system is provided. In a first implementable embodiment of the first aspect, the configuration modes of the RIS-assisted radar system include:

[0007] Mode 1: The radar is configured with one transmit beam and two receive beams. The transmit beam is pointed at the target, one receive beam is pointed at the target, and the other receive beam is pointed at the RIS.

[0008] And / or Mode 2, the radar is configured with two transmit beams and one receive beam, with the receive beam pointing towards the target, one transmit beam pointing towards the target, and the other transmit beam pointing towards the RIS;

[0009] And / or Mode 3, the radar is configured with two transmit beams and one receive beam, the receive beam is pointed at the target, one transmit beam is pointed at the target, and the other transmit beam is pointed at the RIS, and the echo delay is resolved by the orthogonal waveforms transmitted by the two transmit beams;

[0010] The configuration method includes:

[0011] The receiving signal-to-noise ratio algorithm is determined based on the characteristic parameters and location of the radar, RIS, and target for different configuration modes.

[0012] Using the corresponding receive signal-to-noise ratio algorithm, the receive signal-to-noise ratio of the RIS-assisted radar system under different configuration modes is calculated respectively;

[0013] The received signal-to-noise ratios corresponding to different configuration modes are compared, and the optimal configuration mode is selected to configure the RIS-assisted radar system.

[0014] In conjunction with the first possible implementation of the first aspect, in the second possible implementation of the first aspect, the algorithm for determining the received signal-to-noise ratio corresponding to different configuration modes includes:

[0015] When the positions of the radar and RIS satisfy ξ<λD t hour,

[0016] The specific formula for calculating the received signal-to-noise ratio for Mode 1 is as follows:

[0017]

[0018] And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 2 is as follows:

[0019]

[0020] And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 3 is as follows:

[0021]

[0022] in,

[0023]

[0024] Where ξ is the angle between the line connecting the target and the radar, and the line connecting the target and the RIS, λ is the radar signal wavelength, and D t Let P be the target shape, σ be the target surface area observed by radar, and P be the target shape. w Let P be the variance, ε∈[0,1] be the radar's transmit power coefficient, and P be the transmit power coefficient. r For radar transmission power, G rt G is the gain for the radar beam pointing towards the target. rs , l Let λ be the gain of the radar beam pointing to the l-th element of RIS, and λ be the wavelength of the radar transmitted signal. sr , l S is the effective aperture of the l-th element of the RIS in the path from target to RIS to radar. st , l Let be the effective aperture of the l-th cell of the RIS in the path from radar to RIS to target; ρ be the distance from the radar to the target; and d be the effective aperture of the l-th cell of the RIS. t Let d be the distance from the center of the RIS to the target. r , l Let be the distance from the l-th unit of RIS to the radar.

[0025] In conjunction with the first possible implementation of the first aspect, in the third possible implementation of the first aspect, the algorithm for determining the received signal-to-noise ratio corresponding to different configuration modes includes:

[0026] When the positions of the radar and RIS satisfy ξ≥λD t ;

[0027] The specific formula for calculating the received signal-to-noise ratio in Mode 1 is as follows:

[0028] SNR1, 1 = SNR0;

[0029]

[0030] And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 2 is as follows:

[0031] SNR2,1=εSNR0;

[0032]

[0033] And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 3 is as follows:

[0034]

[0035] in,

[0036]

[0037] Where, σs is the target surface area observed by the RIS, G sr , l is the gain of the l-th unit of the RIS in the path from the target → RIS → radar, G st , l is the gain of the l-th unit of the RIS in the path from the radar → RIS → target.

[0038] Combined with any one of the first to third implementation manners of the first aspect, in the fourth implementation manner of the first aspect, when the position of the RIS is at d t + d r - ρ ≥ c / W, the configuration mode of the radar is configured as mode 2, d r is the distance from the radar to the center of the RIS, c is the speed of light, and W is the radar signal bandwidth.

[0039] Combined with any one of the first to third implementation manners of the first aspect, in the fifth implementation manner of the first aspect, when the position of the RIS is at d t + d r - ρ < c / W, the configuration mode of the radar is configured as mode 3.

[0040] Second aspect, a method for deploying the position of a RIS-assisted radar system is provided. In the first implementation manner of the second aspect, the deployment method of the RIS-assisted radar system includes proximal deployment and distal deployment, and the position deployment method includes:

[0041] Determine the corresponding deployment method of the RIS at different deployment positions according to the characteristic parameters and positions of the radar and the target;

[0042] Adopt the received signal-to-noise ratio algorithm matching the corresponding deployment method, and calculate the received signal-to-noise ratio of the RIS-assisted radar system when the RIS is deployed at different deployment positions respectively;

[0043] Compare all the calculated received signal-to-noise ratios, and select the best deployment position to deploy the RIS.

[0044] Combined with the first implementation manner of the second aspect, in the second implementation manner of the second aspect, determining the corresponding deployment method of the RIS at the deployment position includes:

[0045] Determine the target shape D t and the radar signal wavelength λ according to the characteristic parameters of the radar and the target;

[0046] Determine the included angle ξ between the line connecting the target and the radar and the line connecting the target and the RIS through the positions of the radar and the target and the deployment position of the RIS;

[0047] Based on the included angle ξ and the target shape D t Determine the deployment method based on the radar signal wavelength λ:

[0048] When ξ < λD t At that time, the deployment method is near-end deployment;

[0049] When ξ≥λD t At that time, the deployment method was remote deployment.

[0050] In conjunction with the first feasible method of the second aspect, in the third feasible method of the second aspect, the received signal-to-noise ratio of the RIS-assisted radar system is calculated when the RIS is deployed at different deployment locations, including:

[0051] When the radar system is deployed at the near end and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0052]

[0053] And / or, when the radar system is deployed at the near end and configured in mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0054]

[0055] And / or, when the radar system is deployed at the near end and configured in mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0056]

[0057] in,

[0058]

[0059] Where σ is the target surface area observed by the radar, and P w Let P be the variance, ε∈[0,1] be the radar's transmit power coefficient, and P be the transmit power coefficient. r For radar transmission power, G rt G is the gain for the radar beam pointing towards the target. rs , l Let λ be the gain of the radar beam pointing to the l-th element of RIS, and λ be the wavelength of the radar transmitted signal. sr , l S is the effective aperture of the l-th element of the RIS in the path from target to RIS to radar. st , l Let be the effective aperture of the l-th cell of the RIS in the path from radar to RIS to target; ρ be the distance from the radar to the target; and d be the effective aperture of the l-th cell of the RIS. t Let d be the distance from the center of the RIS to the target. r , lLet be the distance from the l-th unit of RIS to the radar.

[0060] In conjunction with the first possible implementation of the second aspect, in the fourth possible implementation of the second aspect, the received signal-to-noise ratio of the RIS-assisted radar system is calculated when the RIS is deployed at different deployment locations, including:

[0061] When the radar system is deployed remotely and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0062] SNR1, 1 = SNR0;

[0063]

[0064] And / or, when the radar system is deployed remotely and configured in Mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0065] SNR2,1=εSNR0;

[0066]

[0067] And / or, when the radar system is deployed remotely and configured in mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0068]

[0069] in,

[0070]

[0071] Where, σ s G represents the target surface area observed by RIS. sr , l G represents the gain of the l-th unit of the RIS in the path from target to RIS to radar. st , l This represents the gain of the l-th unit of the RIS in the path from radar to RIS to target.

[0072] Thirdly, a method for deploying a RIS-assisted radar system is provided, including:

[0073] Based on the characteristic parameters and location of the radar and the target, determine the deployment mode of the RIS at different deployment locations;

[0074] Using an algorithm that matches the deployment method and configuration mode of the RIS, the received signal-to-noise ratio of the RIS-assisted radar system under different deployment locations and configuration modes is calculated respectively.

[0075] The calculated received signal-to-noise ratios are compared, and the optimal configuration mode and deployment location are selected to configure the radar and deploy the RIS.

[0076] Beneficial effects: The mode configuration and location deployment method of the RIS-assisted radar system of the present invention can be used to calculate the received signal-to-noise ratio (SNR) of the RIS when deployed in different locations or the radar system in different configuration modes using a matching algorithm. By comparing the SNR of the radar system in different deployment locations or different configuration modes, the optimal deployment scheme with the highest SNR can be selected, and the deployment location of the RIS or the configuration mode of the radar in the RIS-assisted radar system can be reasonably deployed, thereby improving the radar detection performance with excellent cost-effectiveness. Attached Figure Description

[0077] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the specific embodiments will be briefly described below. In all the drawings, the elements or parts are not necessarily drawn to scale.

[0078] Figure 1 A flowchart illustrating a mode configuration method for a RIS-assisted radar system according to an embodiment of the present invention;

[0079] Figure 2 A flowchart illustrating a method for deploying a RIS-assisted radar system according to an embodiment of the present invention;

[0080] Figure 3 A flowchart illustrating a method for deploying a RIS-assisted radar system according to an embodiment of the present invention;

[0081] Figure 4 This is a structural diagram of a RIS-assisted radar system according to an embodiment of the present invention;

[0082] Figure 5 This is a schematic diagram of near-end deployment provided in an embodiment of the present invention;

[0083] Figure 6 This is a schematic diagram of remote deployment provided in an embodiment of the present invention. Detailed Implementation

[0084] The embodiments of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings. These embodiments are merely illustrative of the technical solution of the present invention and are therefore intended to limit the scope of protection of the present invention.

[0085] It should be understood that in this embodiment, RIS is short for Reconfigurable Smart Surface, which can be used to assist radar in monitoring various parameters of targets with known positions and characteristic parameters, such as displacement and deformation.

[0086] Example 1

[0087] like Figure 1 The flowchart shown illustrates the mode configuration method for a RIS-assisted radar system. This radar system includes multiple configuration modes, namely:

[0088] In mode 1, the radar has one transmit beam and two receive beams. The transmit beam is pointed at the target, one receive beam is pointed at the target, and the other receive beam is pointed at the RIS.

[0089] And / or Mode 2, the radar has two transmit beams and one receive beam, the receive beam is pointed at the target, one transmit beam is pointed at the target, and the other transmit beam is pointed at the RIS;

[0090] In mode 3 and / or mode 4, the radar has two transmit beams and one receive beam, with the receive beam pointing towards the target, one transmit beam pointing towards the target, and the other transmit beam pointing towards the RIS, and transmits orthogonal waveforms to resolve echo delay through the two transmit beams.

[0091] Specifically, such as Figure 4 As shown, the RIS-assisted radar system includes a radar and a RIS. The radar has three configuration modes: Mode 1, Mode 2, and Mode 3.

[0092] In mode 1, the radar has one transmit beam and two receive beams. The transmit beam is pointed at the target, one receive beam is pointed at the target, and the other receive beam is pointed at the RIS.

[0093] In Mode 2, the radar has two transmit beams and one receive beam. The receive beam is pointed at the target, one transmit beam is pointed at the target, and the other transmit beam is pointed at the RIS.

[0094] In Mode 3, the radar has two transmit beams and one receive beam. The receive beam is pointed at the target, one transmit beam is pointed at the target, and the other transmit beam is pointed at the RIS. The radar transmits orthogonal waveforms through the two transmit beams to resolve the echo delay.

[0095] During the radar system's detection process, the configuration mode of the radar system can be configured according to the detection effect on the target in order to enable the radar system to achieve the best detection performance.

[0096] In this embodiment, the optional configuration mode configuration method for the RIS-assisted radar system includes:

[0097] Step 1: Determine the receiving signal-to-noise ratio algorithm corresponding to different configuration modes based on the characteristic parameters and positions of the radar, RIS, and target;

[0098] Step 2: Using the corresponding receive signal-to-noise ratio algorithm, calculate the receive signal-to-noise ratio of the RIS-assisted radar system under different configuration modes;

[0099] Step 3: Compare the received signal-to-noise ratios corresponding to different configuration modes, and select the best configuration mode to configure the RIS-assisted radar system.

[0100] Specifically, firstly, the receive signal-to-noise ratio (RSR) algorithm corresponding to different configuration modes can be determined based on the characteristic parameters and positions of the radar, RIS, and target in the RIS-assisted radar system. Then, the RSR of the RIS-assisted radar system under different configuration modes can be calculated using the corresponding RSR algorithm. Finally, the calculated RSRs for different configuration modes are compared, and the configuration mode corresponding to the highest RSR is selected to configure the radar system, thereby improving radar detection performance with excellent cost-effectiveness.

[0101] In this embodiment, optionally, in step 1, determining the received signal-to-noise ratio algorithm corresponding to different configuration modes includes:

[0102] When the positions of the radar and RIS satisfy ξ<λD t hour,

[0103] The specific formula for calculating the received signal-to-noise ratio for Mode 1 is as follows:

[0104]

[0105] And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 2 is as follows:

[0106]

[0107] And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 3 is as follows:

[0108]

[0109] in,

[0110]

[0111] Where ξ is the angle between the line connecting the target and the radar, and the line connecting the target and the RIS, λ is the radar signal wavelength, and D t Let P be the target shape, σ be the target surface area observed by radar, and P be the target shape. w Let P be the variance, ε∈[0,1] be the radar's transmit power coefficient, and P be the transmit power coefficient. r For radar transmission power, G rt G is the gain for the radar beam pointing towards the target. rs ,l Let λ be the gain of the radar beam pointing to the l-th element of RIS, and λ be the wavelength of the radar transmitted signal. sr , l S is the effective aperture of the l-th element of the RIS in the path from target to RIS to radar. st , l Let be the effective aperture of the l-th cell of the RIS in the path from radar to RIS to target; ρ be the distance from the radar to the target; and d be the effective aperture of the l-th cell of the RIS. t Let d be the distance from the center of the RIS to the target. r , l Let be the distance from the l-th unit of RIS to the radar.

[0112] When the positions of RIS, radar, and target satisfy ξ < λD t This allows both the radar and the RIS to be illuminated by the same echo reflected from the target, making the target surface area observed by both the radar and the RIS appear the same. In this case, the phase of the RIS is set to... This allows the received signals from the direct echo path and the indirect echo path to be phase-aligned, and the best detection performance can be obtained by adding and merging the two signals.

[0113] in, β is the RIS phase, β is the target-radar channel phase, {ψ r,l |l=1,…,L} represents the radar-RIS channel phase, {ψ t,l |l=1,…,L} represents the RIS-target channel phase.

[0114] Example 2

[0115] Example 2 is largely the same as Example 1, with the main difference being: the algorithm for determining the received signal-to-noise ratio corresponding to different configuration modes includes:

[0116] When the positions of the radar, target, and RIS satisfy ξ≥λD t At that time, the radar and RIS are illuminated by different echoes reflected from the target, resulting in different target surface areas observed by the radar and RIS. Since the positions of the radar and RIS are fixed, the radar waveform is determined. By setting the phase of the RIS to... This allows the received signals from the direct and indirect echo paths to be phase-aligned, and the optimal detection performance can be obtained by adding and combining the two signals. β s For the target-RIS first unit channel phase β s =ψ t,1 .

[0117] At this point, the specific formula for calculating the received signal-to-noise ratio in Mode 1 is as follows:

[0118] SNR1, 1 = SNR0;

[0119]

[0120] And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 2 is as follows:

[0121] SNR2,1=εSNR0;

[0122]

[0123] And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 3 is as follows:

[0124]

[0125] in,

[0126]

[0127] Where, σ s G represents the target surface area observed by RIS. sr , l G represents the gain of the l-th unit of the RIS in the path from target to RIS to radar. st , l This represents the gain of the l-th unit of the RIS in the path from radar to RIS to target.

[0128] Example 3

[0129] Implementation 3 is largely the same as Implementation 2, with the main difference being that: in this embodiment, optionally, when the RIS is deployed at location d... t +d r When -ρ≥c / W, the radar is configured in mode 2, d r Where c is the distance from the radar to the center of RIS, and W is the speed of light.

[0130] Specifically, before calculating the received signal-to-noise ratio (SNR), the distance from the radar to the RIS center, the distance ρ from the radar to the target, and the distance d from the RIS center to the target can be used as a reference. t A preliminary assessment is made regarding the required radar configuration mode. This is based on the following conditions: the distance from the radar to the RIS center, the distance from the radar to the target, and the distance from the RIS center to the target satisfy d. t +d rWhen -ρ≥c / W, the direct echo delay of the radar-target-radar path and the indirect echo delay of the radar-RIS-target-radar path are indistinguishable, which means that the delay cannot be resolved by transmitting orthogonal waveforms through two transmitting beams. Therefore, when the RIS is arranged at this deployment position, the radar needs to be configured in Mode 2. In this way, when the RIS is arranged at this deployment position, only the received signal-to-noise ratio of the radar system in Mode 2 needs to be calculated. Thus, the amount of data calculation is reduced and the deployment efficiency is improved.

[0131] Similarly, when the deployment position of the RIS is at d t +d r When -ρ<c / W, the configuration mode of the radar is configured as Mode 3. The direct echo delay of the radar-target-radar path and the indirect echo delay of the radar-RIS-target-radar path are distinguishable, which means that the delay can be resolved by transmitting orthogonal waveforms through two transmitting beams. Therefore, when the RIS is arranged at this deployment position, the radar needs to be configured in Mode 3. In this way, when the RIS is arranged at this deployment position, only the received signal-to-noise ratio of the radar system in Mode 3 needs to be calculated. Thus, the amount of data calculation is reduced and the deployment efficiency is improved.

[0132] Embodiment 4

[0133] As Figure 2 shown in the flowchart of the location deployment method of the RIS-assisted radar system method, this deployment method includes:

[0134] Step S1: Determine the corresponding deployment methods of the RIS at different deployment positions according to the characteristic parameters and positions of the radar and the target;

[0135] Step S2: Adopt the received signal-to-noise ratio algorithm matching the corresponding deployment method, and calculate the received signal-to-noise ratio of the RIS-assisted radar system when the RIS is deployed at different deployment positions respectively;

[0136] Step S3: Compare all the calculated received signal-to-noise ratios, and select the best deployment position to deploy the RIS.

[0137] Specifically, firstly, the deployment method of the RIS (Radio Assisted Rectifier) ​​at different deployment locations can be determined based on the characteristic parameters and positions of the radar and the target. In this embodiment, the deployment methods include near-end deployment and far-end deployment. Since the target echoes received by the RIS differ depending on whether it is deployed near or far from the radar, after determining the deployment method corresponding to the RIS at the deployment location, an algorithm matching the deployment method and the configuration mode of the RIS-assisted radar system can be used to calculate the received signal-to-noise ratio (SNR) of the RIS-assisted radar system at different deployment locations. Finally, all calculated SNRs are compared, and the deployment location corresponding to the highest SNR is selected for RIS deployment, thereby achieving the goal of improving radar detection performance with excellent cost-effectiveness.

[0138] In this embodiment, optionally, in step S1, determining the deployment method corresponding to the RIS at the deployment location includes:

[0139] Determine the target shape D based on radar and target characteristic parameters. t and radar signal wavelength λ;

[0140] By determining the positions of the radar and the target, as well as the deployment location of the RIS, the angle ξ between the line connecting the target and the radar, and between the line connecting the target and the RIS is determined.

[0141] Based on the included angle ξ and the target shape D t Determine the deployment method based on the radar signal wavelength λ:

[0142] When ξ < λD t At that time, the deployment method is near-end deployment, such as Figure 5 As shown;

[0143] When ξ≥λD t At that time, the deployment method is remote deployment, such as Figure 6 As shown.

[0144] Specifically, when determining the deployment method of a RIS at its deployment location, the first step is to determine the angle between the line connecting the target and the radar and the line connecting the target and the RIS, based on the known deployment location, radar location, and target location. Then, the target shape and radar signal wavelength can be determined using the characteristic parameters of the radar and the target. Finally, by using the angle, radar signal wavelength, and target shape, it can be determined whether the RIS is deployed at a long-range or short-range location.

[0145] In this embodiment, optionally, in step S2, calculating the received signal-to-noise ratio of the RIS-assisted radar system when the RIS is deployed at different deployment locations includes:

[0146] When the radar system is deployed at the near end and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0147]

[0148] And / or, when the radar system is deployed at the near end and configured in mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0149]

[0150] And / or, when the radar system is deployed at the near end and configured in mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0151]

[0152] in,

[0153]

[0154] Where σ is the target surface area observed by radar, and P w Let P be the variance, ε∈[0,1] be the radar's transmit power coefficient, and P be the transmit power coefficient. r For radar transmission power, G rt G is the gain for the radar beam pointing towards the target. rs , l Let λ be the gain of the radar beam pointing to the l-th element of RIS, and λ be the wavelength of the radar transmitted signal. sr , l S is the effective aperture of the l-th element of the RIS in the path from target to RIS to radar. st , l Let be the effective aperture of the l-th cell of the RIS in the path from radar to RIS to target; ρ be the distance from the radar to the target; and d be the effective aperture of the l-th cell of the RIS. t Let d be the distance from the center of the RIS to the target. r , l Let be the distance from the l-th unit of RIS to the radar.

[0155] Among them, the distance ρ from the radar to the target and the distance d from the center of the RIS to the target are... t The distance d from the l-th unit of RIS to the radar r , l All of these can be calculated from the deployment location of radar and RIS, and the target location.

[0156] Example 5

[0157] Example 5 is largely the same as Example 4, the main difference being that step S2 includes:

[0158] When the radar system is deployed remotely and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0159] SNR1, 1 = SNR0;

[0160]

[0161] And / or, when the radar system is deployed remotely and configured in Mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0162] SNR2,1=εSNR0;

[0163]

[0164] And / or, when the radar system is deployed remotely and configured in mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows:

[0165]

[0166] in,

[0167]

[0168] Where, σ s G represents the target surface area observed by RIS. sr , l G represents the gain of the l-th unit of the RIS in the path from target to RIS to radar. st , l This represents the gain of the l-th unit of the RIS in the path from radar to RIS to target.

[0169] By comparing the received signal-to-noise ratios (SNRs) of the RIS-assisted radar system at various deployment locations, the deployment location with the highest SNR can be selected to place the RIS, thereby improving radar detection performance with excellent cost-effectiveness.

[0170] Example 6

[0171] Example 6 is largely the same as the examples above, with the main difference being: Figure 3 As shown, the deployment method includes:

[0172] Step D1: Based on the characteristic parameters and location of the radar and the target, determine the deployment method of the RIS at different deployment locations;

[0173] Step D2: Using an algorithm that matches the deployment method and configuration mode of the RIS, calculate the received signal-to-noise ratio of the RIS-assisted radar system under different deployment locations and configuration modes;

[0174] Step D3: Compare all the calculated received signal-to-noise ratios, select the best configuration mode and deployment location to configure the radar and deploy the RIS.

[0175] Specifically, firstly, based on the characteristic parameters of the radar and the target, the deployment mode corresponding to the RIS (Radio Receiving System) at different deployment locations can be determined. In this embodiment, the deployment modes include near-end deployment and far-end deployment. Since the target echo received by the RIS differs when deployed near-end and far-end, after determining the deployment mode corresponding to the RIS at the deployment location, an algorithm matching the deployment mode can be used to calculate the received signal-to-noise ratio (SNR) of the RIS under different configuration modes. This yields the received signal ratios corresponding to the three configuration modes when the RIS is deployed at different locations. Finally, all calculated SNRs are compared, and the configuration mode and deployment location corresponding to the highest SNR are selected to form a deployment scheme. The configuration mode of the radar system and the deployment location of the RIS are then configured according to the deployment scheme, thereby achieving the goal of improving radar detection performance with excellent cost-effectiveness.

[0176] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A mode configuration method for a RIS-assisted radar system, characterized in that: The configuration modes of the RIS-assisted radar system include: Mode 1: The radar is configured with one transmit beam and two receive beams. The transmit beam is pointed at the target, one receive beam is pointed at the target, and the other receive beam is pointed at the RIS. And / or Mode 2, the radar is configured with two transmit beams and one receive beam, with the receive beam pointing towards the target, one transmit beam pointing towards the target, and the other transmit beam pointing towards the RIS; And / or Mode 3, the radar is configured with two transmit beams and one receive beam, the receive beam is pointed at the target, one transmit beam is pointed at the target, and the other transmit beam is pointed at the RIS, and the echo delay is resolved by the orthogonal waveforms transmitted by the two transmit beams; The configuration method includes: The receiving signal-to-noise ratio algorithm is determined based on the characteristic parameters and location of the radar, RIS, and target for different configuration modes. Using the corresponding receive signal-to-noise ratio algorithm, the receive signal-to-noise ratio of the RIS-assisted radar system under different configuration modes is calculated respectively; The received signal-to-noise ratios corresponding to different configuration modes are compared, and the optimal configuration mode is selected to configure the RIS-assisted radar system. Determining the received signal-to-noise ratio algorithm corresponding to different configuration modes includes: When the positions of the radar and RIS satisfy hour, The specific formula for calculating the received signal-to-noise ratio for Mode 1 is as follows: ； And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 2 is as follows: ； And / or, the specific formula for calculating the received signal-to-noise ratio corresponding to Mode 3 is as follows: ； in, , , ; ， ； in, The angle between the line connecting the target and the radar, and the angle between the line connecting the target and the RIS. For the target shape, The target surface area as observed by radar. For variance, This represents the radar's transmit power coefficient. For radar transmission power, The gain for the radar beam pointing towards the target. The gain for the radar beam pointing to the l-th element of RIS. The wavelength of the radar transmitted signal. The effective aperture of the l-th element of the RIS in the path from target to RIS to radar. The effective aperture of the l-th cell in the radar → RIS → target path; The distance at which the radar reaches its target. The distance from the RIS center to the target. Let L be the distance from the l-th unit of the RIS to the radar, and L be the number of units in the RIS. Determining the received signal-to-noise ratio algorithm corresponding to different configuration modes includes: When the positions of the radar and RIS satisfy ; The specific formula for calculating the received signal-to-noise ratio in Mode 1 is as follows: ； ； And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 2 is as follows: ； ； And / or, the specific formula for calculating the received signal-to-noise ratio in Mode 3 is as follows: ； in, ; ； ； in, The target surface area observed by RIS. The gain of the l-th unit of the RIS in the path from target to RIS to radar. This represents the gain of the l-th unit of the RIS in the path from radar to RIS to target.

2. The mode configuration method for the RIS-assisted radar system according to claim 1, characterized in that, When RIS is located In this situation, the radar is configured in mode 2. The distance from the radar to the center of the RIS At the speed of light, This refers to the radar signal bandwidth.

3. The mode configuration method for the RIS-assisted radar system according to claim 1, characterized in that, When RIS is located In this case, the radar is configured in mode 3.

4. A method for deploying a RIS-assisted radar system, characterized in that, The RIS-assisted radar system can be deployed in both near-end and far-end configurations, with the following location deployment methods: Based on the characteristic parameters and location of the radar and the target, determine the deployment mode of the RIS at different deployment locations; Using the corresponding signal-to-noise ratio (SNR) algorithm that matches the deployment method, the SNR of the RIS-assisted radar system is calculated when the RIS is deployed at different locations. Compare all the calculated received signal-to-noise ratios and select the optimal deployment location for the RIS; Determine the deployment method for the RIS at the deployment location, including: Determine the target shape based on radar and target characteristic parameters. and radar signal wavelength ; By determining the positions of the radar and the target, as well as the deployment location of the RIS, the angles between the lines connecting the target and the radar, and between the target and the RIS, can be established. ; According to the included angle Target shape and radar signal wavelength Determine the deployment method: when At that time, the deployment method is near-end deployment; when At that time, the deployment method was remote deployment; Calculate the received signal-to-noise ratio of the RIS-assisted radar system when deployed at different locations, including: When the radar system is deployed at the near end and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows: ； And / or, when the radar system is deployed at the near end and configured in mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows: ； And / or, when the radar system is deployed at the near end and configured in mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows: ； in, , , ; ， ； in, The target surface area as observed by radar. For variance, This represents the radar's transmit power coefficient. For radar transmission power, The gain for the radar beam pointing towards the target. The gain for the radar beam pointing to the l-th element of RIS. The wavelength of the radar transmitted signal. The effective aperture of the l-th element of the RIS in the path from target to RIS to radar. The effective aperture of the l-th cell in the radar → RIS → target path; The distance at which the radar reaches its target. The distance from the RIS center to the target. This represents the distance from the l-th unit of the RIS to the radar. Calculate the received signal-to-noise ratio of the RIS-assisted radar system when deployed at different locations, including: When the radar system is deployed remotely and configured in Mode 1, the specific formula for calculating the received signal-to-noise ratio is as follows: ； ； And / or, when the radar system is deployed remotely and configured in Mode 2, the specific formula for calculating the received signal-to-noise ratio is as follows: ； ； And / or, when the radar system is deployed remotely and configured in Mode 3, the specific formula for calculating the received signal-to-noise ratio is as follows: ； in, ; ； ； in, The target surface area observed by RIS. The gain of the l-th unit of the RIS in the path from target to RIS to radar. This represents the gain of the l-th unit of the RIS in the path from radar to RIS to target.

5. A method for deploying a RIS-assisted radar system, characterized in that, include: Based on the characteristic parameters and location of the radar and the target, the deployment method described in claim 4 is used to determine the deployment mode of the RIS at different deployment locations; Using the mode configuration method as described in claim 1, the received signal-to-noise ratio of the RIS assisted radar system under different deployment locations and configuration modes is calculated respectively; The calculated signal-to-noise ratios of all receivers are compared, and the optimal configuration mode and deployment location are selected to configure the radar and deploy the RIS.

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