Bistatic communication perception integrated beam forming design method based on interference utilization

Abstract

The invention provides a bistatic communication perception integrated beam forming design method based on interference utilization, which belongs to the technical field of base communication, constructs a bistatic communication perception integrated system, and re-derives a Cramer-Rao bound of point target angle estimation under a bistatic model. 16 QAM constructive interference is introduced into communication and perception integrated beam forming design for the first time, the communication and perception integrated beam forming design is modeled into an optimization problem with an optimization variable being a communication signal beam forming matrix, and a target function of the problem is a Cramer-Rao bound of angle estimation of a point target representing perception performance; the constraints include that the power of a base station transmitting signal must be within a power prediction and the communication user receiving signal constraint satisfying 16QAM constructive interference, and the Cramer-Rao bound of the perception performance is reduced as much as possible on the premise that the communication user side satisfies the constructive interference constraint.

Description

Technical Field

[0001] The present invention belongs to the technical field of base communication, and in particular relates to a dual-base communication perception integrated beamforming design method based on interference utilization. Background Art

[0002] For the vision of future communication systems, 6G wireless communication technology needs to meet more stringent performance indicators, including extremely high throughput, ultra-low latency, and high energy efficiency. In addition, wireless networks need to support a variety of intelligent applications, which not only place higher demands on communication performance, but also have increasing demands on perception capabilities. Technology trends show that future networks will not only need to meet traditional communication needs, but will also provide ubiquitous environmental perception services.

[0003] With the evolution of technology, wireless sensing and wireless communication technologies have significant similarities in hardware architecture and signal processing algorithms, and they perform particularly well under high-frequency and broadband conditions. At the same time, the size of antennas in future systems will continue to increase, which provides technical feasibility for the deep integration of communication and perception. Therefore, integrating communication and perception into a unified platform to share spectrum, energy, and hardware resources becomes a natural and efficient solution. Integrated sensing and communications (ISAC) technology can significantly improve spectrum utilization efficiency and reduce software and hardware complexity by sharing software and hardware platforms in terms of time, frequency, and space resources, while serving communication and perception needs.

[0004] A large number of studies have been conducted on the ISAC system from different perspectives, and transmit beamforming design is an important part of it. Transmit beamforming can focus the transmitted wireless signal in the desired direction, thereby achieving high-speed data transmission and high-precision target perception. The beamforming problem has been studied a lot in the 5G era, but this problem is more difficult for the ISAC system, because the beamforming in the ISAC system often needs to meet the requirements of communication and perception at the same time. How to design the beamforming matrix at the transmitter so that both communication performance and perception performance can achieve a good effect is the key to the ISAC beamforming design. Most of the existing work focuses on the scenario setting of a single base station, expanding the communication base station into a full-duplex dual-function base station (BS) with both communication and perception functions. This model may have serious self-interference, limited sensing coverage and other problems. However, the current work on the design of integrated communication and perception beamforming for multiple base stations is still incomplete. Based on this, the present invention constructs a dual-base communication and perception integrated model, re-derives the Cramer-Rao bound for point target angle estimation based on the dual-base model, and introduces 16QAM constructive interference for the first time in the communication and perception integrated beamforming design, relaxes the constraints on communication users, and can achieve better communication performance while ensuring certain communication performance. In the above context, the communication and perception integrated beamforming design work is considered. Summary of the invention

[0005] The purpose of the present invention is to provide a dual-base communication perception integrated beamforming design method based on interference utilization, aiming to solve the problems that the model in the prior art may have serious self-interference and limited sensing coverage, as well as the current problem that the work on the communication perception integrated beamforming design of multiple base stations is still imperfect.

[0006] To achieve the above object, the present invention provides the following technical solutions: A dual-base communication perception integrated beamforming design method based on interference utilization includes the following steps: Step 1: After the signal transmitted by the transmitting base station detects the sensing target, an echo signal is generated, which is received by the sensing base station. The sensing base station performs angle estimation based on the echo signal and derives the Cramér-Rao Bound (CRB) of the angle estimation. Step 2: Introduce 16QAM constructive interference (CI), and select the corresponding communication constraints under constructive interference according to the transmitted 16QAM signal; Step 3. According to the derived communication constraints based on constructive interference and the Cramer-Rao bound of angle estimation, a problem of minimizing the Cramer-Rao bound of angle estimation while ensuring communication performance is constructed. The original non-convex problem is transformed into a convex problem through the semidefinite relaxation (SDR) method, and the CVX toolbox is used to solve it to obtain the optimal beamforming matrix.

[0007] As a preferred solution of the present invention, the scene includes a transmitter station, a sensing base station, at least one downlink communication user and a sensing target, and the transmitting base station sends to the first The 16QAM signal of a communication user is , No. The beamforming matrix of a communication user is , transmit signal for: , Furthermore, the baseband signals sent to different communication users are independent of each other, and the baseband signals are known at the transmitting base station and the sensing base station.

[0008] As a preferred solution of the present invention, setting and Corresponding to the angle of the target relative to the transmitting base station and the sensing base station, the sensing channel matrix of the transmitting base station via the sensing target to the sensing base station It is expressed as: , in and are the receiving array response vector and the transmitting array response vector, respectively, It is the reflection coefficient that takes into account the path loss and radar cross-section (RCS) of the perceived target. represents the conjugate transpose of a vector, Represents the transpose of a vector.

[0009] As a preferred solution of the present invention, the echo signal received by the sensing base station is: ; In the formula, for A noise vector, where each item has a mean of 0 and a variance of Additive Gaussian white noise in the perceptual channel; The unknown parameters in the sensing channel are given by Composition, of which , , the Fisher information matrix for estimating the unknown target parameters is expressed as: ; Where: Indicates vectorization of the received signal. represents taking the real part; In the matrix: , , , Each entry in the matrix can be calculated as follows: ; So each entry in the matrix is: , ; , ; , ; , ; , ; in, , express right Seeking guidance, express right Seeking guidance, ; The perceived CRB matrix is: ;

[0010] estimate and The Cramero boundary is The diagonal elements of For estimation and The sum of Cramer-Rao bounds is used as a representation of perceptual performance.

[0011] As a preferred embodiment of the present invention, The received signal at each user It is expressed as: ; in, Indicates the transmitting base station to the The channels of the communication users, The mean is 0 and the variance is The additive Gaussian white noise is Noise at each user.

[0012] As a preferred solution of the present invention, based on the 16QAM constellation diagram, it is divided into four parts, and their constructive interference (CI) are as follows: Ⅰ: For the four constellation points enclosed in the 16QAM constellation diagram, if the transmitted signal Corresponding to one of these four points, the constraint is: ; ; II: For the four constellation points on the upper and lower sides of the 16QAM constellation diagram close to the imaginary axis, the constructive area extends along the decision boundaries on the left and right sides of the constellation point away from the real axis. Corresponding to one of these four points, the constraint is: ; ; III: For the four constellation points on the left and right sides of the 16QAM constellation diagram close to the real axis, the constructive area extends along the decision boundaries on both sides of the constellation point away from the imaginary axis. Corresponding to one of these four points, the constraint is: ; ; IV: For the constellation points at the four outer vertices in the 16QAM constellation diagram, the constructive area extends infinitely away from the imaginary axis and the real axis. Corresponding to one of these four points, the constraint is: ; ; in, Indicates The noise-free received signal of each communication user is Indicates The threshold of the signal to interference plus noise ratio (SINR) of each communication user, The SINR of a communication user without CI is , after the introduction of CI, it becomes , and satisfy the corresponding conversion relationship; In the formula: Symbol Indicates that different symbols correspond to different quadrants. In the first quadrant, represent ; In the second quadrant, the real axis represent , the imaginary axis part represent ; In the third quadrant, represent ; In the fourth quadrant, the real axis represent , the imaginary axis part represent .

[0013] As a preferred solution of the present invention, based on the 16QAM constellation diagram, it is divided into four parts, and their constructive interference (CI) are as follows: Ⅰ: For the four constellation points enclosed in the 16QAM constellation diagram, if the transmitted signal Corresponding to one of these four points, the constraint is: ; ; II: For the four constellation points on the upper and lower sides of the 16QAM constellation diagram close to the imaginary axis, the constructive area extends along the decision boundaries on the left and right sides of the constellation point away from the real axis. Corresponding to one of these four points, the constraint is: ; ; III: For the four constellation points on the left and right sides of the 16QAM constellation diagram close to the real axis, the constructive area extends along the decision boundaries on both sides of the constellation point away from the imaginary axis. Corresponding to one of these four points, the constraint is: ; ; IV: For the constellation points at the four outer vertices in the 16QAM constellation diagram, the constructive area extends infinitely away from the imaginary axis and the real axis. Corresponding to one of these four points, the constraint is: ; ; in, Indicates The noise-free received signal of each communication user is Indicates The threshold of the signal to interference plus noise ratio (SINR) of each communication user, The SINR of a communication user without CI is , after the introduction of CI, it becomes , and satisfy the corresponding conversion relationship; In the formula: Symbol Indicates that different symbols correspond to different quadrants. In the first quadrant, represent ; In the second quadrant, the real axis represent , the imaginary axis part represent ; In the third quadrant, represent ; In the fourth quadrant, the real axis represent , the imaginary axis part represent .

[0014] As a preferred solution of the present invention, the power constraint of the transmitted signal is: ; In the formula, Represents a given power budget.

[0015] As a preferred solution of the present invention, the optimization problem to be solved after introducing CI is: ; Converting this into its equivalent form: ; in is the auxiliary matrix, tr(·) represents the trace of the matrix, which becomes: ; Here As auxiliary variables, relax it to , which is equivalent to the following linear matrix inequality: ; The final optimization problem is transformed into: ; The transformed optimization problem is a convex optimization problem, which is solved using the CVX tool.

[0016] As a preferred solution of the present invention, it includes a transmitting base station, a sensing base station, at least one downlink communication user and a sensing target. The transmitting base station transmits signals to communicate with the communication user and sense the target. The sensing base station is used to receive the target echo signal and perform angle estimation.

[0017] As a preferred solution of the present invention, the transmitting base station is equipped with antennas, the sensing base station is equipped with antennas, and , the communication user is configured with a single antenna, and the sensing target is a stationary point object.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention constructs a dual-base communication and perception integrated model, based on which the Cramer-Rao bound for point target angle estimation is re-derived. In this way, a more accurate basis for system performance evaluation is provided. Compared with the single-base station model, it can better adapt to communication and perception tasks in multi-base station scenarios, effectively reduce self-interference and expand the sensing coverage, thereby improving the overall performance of the system.

[0019] 2. The present invention introduces 16QAM constructive interference into the communication-aware integrated beamforming design for the first time, formulates corresponding communication constraints by analyzing different areas of the 16QAM constellation diagram, and relaxes the communication constraints while ensuring communication reliability. This enables the system to utilize interference more effectively, convert multi-user interference into beneficial interference, improve the communication achievable rate of legitimate users, and optimize communication performance.

[0020] 3. In the present invention, by comprehensively considering the communication constraints based on constructive interference and the Cramer-Rao bound of angle estimation, an optimization problem is constructed and solved, and the original non-convex problem is transformed into a convex problem to solve the optimal beamforming matrix. While ensuring the communication performance, the Cramer-Rao bound of angle estimation is reduced as much as possible, thereby realizing the joint optimization of communication and perception performance. This enables the system to significantly improve the perception performance while ensuring a certain communication performance, thereby achieving a better overall performance balance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings: Figure 1 It is a system model diagram in the present invention; Figure 2 Schematic diagram of 16QAM constructive interference in the present invention; Figure 3 is a curve diagram showing the variation of the Cramer-Rao bound with the power budget in the present invention; Figure 4 It is a curve diagram showing the variation of the achievable rate with the power budget in the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Example 1 See also Figure 1 - Figure 4 , the present invention provides the following technical solutions: A dual-base communication perception integrated beamforming design method based on interference utilization includes the following steps: Step 1: After the signal transmitted by the transmitting base station detects the sensing target, an echo signal is generated, which is received by the sensing base station. The sensing base station performs angle estimation based on the echo signal and derives the Cramér-Rao Bound (CRB) of the angle estimation. Step 2: Introduce 16QAM constructive interference (CI), and select the corresponding communication constraints under constructive interference according to the transmitted 16QAM signal; Step 3. According to the derived communication constraints based on constructive interference and the Cramer-Rao bound of angle estimation, a problem of minimizing the Cramer-Rao bound of angle estimation while ensuring communication performance is constructed. The original non-convex problem is transformed into a convex problem through the semidefinite relaxation (SDR) method, and the CVX toolbox is used to solve it to obtain the optimal beamforming matrix.

[0024] In a specific embodiment of the present invention, the purpose of the present invention is to solve the problem of communication-perception integrated beamforming design, and to establish a communication-perception integrated system model. The model is composed of dual bases, multiple communication users and a single perception target, and constructive interference is introduced to relax communication constraints while ensuring communication performance. By deriving the Cramer-Rao bound of angle estimation under the dual-base model, under the communication constraints of constructive interference and the transmission signal power budget constraints, the beamforming vector of the transmitting end is optimized to minimize the Cramer-Rao bound of angle estimation, thereby reducing the Cramer-Rao bound of angle estimation as much as possible while ensuring communication performance, and improving perception performance. Figure 1 The scenario of the present invention is demonstrated, where a transmitting base station transmits a signal to communicate with a communication user, and at the same time uses the transmitted signal to sense a target object in the scene, and the generated echo signal is received by the sensing base station and parameter estimation is performed; Figure 2 The constructive interference diagram of the 16QAM constellation diagram is shown. The constructive interference of 16QAM is introduced, and the corresponding constructive interference constraint is selected according to the area where the constellation point of the generated 16QAM signal is located. The echo signal is represented by establishing a dual-base station perception channel model, and the Cramer-Rao bound of the angle estimation is derived based on the echo signal. Under the communication constraints of constructive interference and the power budget constraints of the transmitted signal, the Cramer-Rao bound is minimized to obtain the transmitting end beamforming vector that makes the transmitted signal meet the communication constraints and has good perception performance.

[0025] For details, please refer to Figure 1 - Figure 2 , the following is a more detailed description of the process in which the transmitting base station sends a signal to communicate with the communication user, and uses the signal to sense the target to generate an echo signal, and the echo signal is received by the sensing base station as a scenario: The present invention considers the beamforming design of the dual-base station communication perception integrated system, and the transmitting base station has antennas, sensing base stations have antennas, and , the communication user is a single antenna configuration, the single point target is a stationary point object, the transmitting base station transmits a communication signal, and uses the signal to sense the single point target in the scene while communicating with the downlink communication user; the transmitting signal of the transmitting base station is expressed as:

[0026] in, The transmitting base station sends The 16QAM signal of each communication user is randomly generated. The transmitter is for The beamforming matrix of each communication user sends baseband signals to different communication users. Independent of each other, , express and The baseband signal is known at both the transmitting base station and the sensing base station; According to the transmitted signal, the power of the transmitted signal can be obtained as , represents the square of the vector modulus, so the power constraint is: ; in for a predetermined power budget; set up and They correspond to the angle of the target relative to the transmitting base station and the angle of the target relative to the sensing base station. Since the sensing target is stationary and the transmitting base station and the sensing base station are fixed, the two angles are fixed. Then, the sensing channel in the sensing system It is expressed as: ; in, is a complex coefficient that takes into account the perceived path loss and radar cross-section (RCS), and is taken here as , is the wavelength, is the speed of light, is the carrier frequency, is an imaginary unit, , is the distance from the target to the base station. is the receiving array response vector, is the transmit array response vector, represents the conjugate transpose of a vector, represents the transpose of the vector; the echo signal received by the sensing base station is: ; in, for A noise vector, where each item has a mean of 0 and a variance of Additive white Gaussian noise in the perceptual channel.

[0027] Specifically, the unknown parameters of perception are given by Composition, of which , ; The Fisher information matrix for estimating unknown target parameters is expressed as: ; Here Indicates vectorization of the received signal. represents the real part operation, , , , and each item in the matrix can be calculated by the following formula: ; express right Derivative, each item in the matrix is ​​specifically expressed as: , ; , ; , ; , ; , ; in, , express right Seeking guidance, express right Seeking guidance, represents the covariance matrix of the transmitted signal.

[0028] The perceived CRB matrix is ​​obtained by the inverse of the Fisher information matrix. The perceived CRB matrix is:

[0029] estimate and The Cramero boundary is The diagonal elements of represent Indicates an estimate and The sum of the Cramero bounds, Represents the trace operation of a matrix.

[0030] Set the channel state information (CSI) of the downlink communication channel to be available to the transmitting base station, The received signal at each communication user It is expressed as:

[0031] in Indicates the transmitting base station to the A communication channel for a communication user, the communication channel is set to be a Rayleigh fading channel; The mean is 0 and the variance is The additive Gaussian white noise is Noise at each user.

[0032] Constructive interference (CI) is defined as interference that makes the constellation point of the received symbol far away from the constellation diagram decision threshold. The idea is to relax the constraints on the transmitted symbol so that it is in the constructive interference area. Being in the constructive interference area can be considered as correct identification of the received signal. The constructive interference area is larger than the general traditional area, which also makes the introduction of CI technology able to provide more relaxed optimization for the communication system; Based on the 16QAM constellation diagram, the constellation diagram is divided into four parts to discuss CI constraints separately, as shown in the attached figure Figure 2 As shown: (1) For Figure 2 The constellation points in the box marked with "1" in the figure are completely surrounded by the decision boundary. The constraints should ensure that the received signal reaches the precise constellation point to avoid exceeding the decision boundary. Assuming that the transmitted signal For a point in the region, the corresponding constraint is expressed as:

[0033]

[0034] (2) For Figure 2 The constellation points in the box marked as "2" in the figure should ensure that the received signal falls within the detection area far away from the decision boundary (i.e., the dotted line parallel to the real axis); assuming that the transmitted signal For a point in the region, the corresponding constraint is expressed as:

[0035]

[0036] (3) For Figure 2 The constellation points in the box marked as "3" in the figure should ensure that the received signal falls within the detection area far away from the decision boundary (i.e., the dotted line parallel to the imaginary axis). Assuming that the transmitted signal For a point in the region, the corresponding constraint is expressed as:

[0037]

[0038] (4) For Figure 2 The constellation points in the box marked with "4" in the figure should ensure that the received signal falls in the detection area far away from the decision boundary, because the constellation points in the box marked with "4" are not completely surrounded by the decision boundary and thus have a larger infinitely extended detection area. Assuming that the transmitted signal For a point in the region, the corresponding constraint is expressed as:

[0039]

[0040] in, Indicates Each communication user receives the signal without noise. Indicates The threshold of the signal to interference plus noise ratio (SINR) of each communication user is predefined before the signal is transmitted. The SINR of a communication user without CI is , after the introduction of CI, it becomes .symbol Indicates that different quadrants correspond to different symbols. For example, in the first quadrant, represent ; In the second quadrant, the real axis represent , the imaginary axis part represent ; In the third quadrant, represent ; In the fourth quadrant, the real axis represent , the imaginary axis part represent .

[0041] After introducing constructive interference, the Cramer-Rao bound of angle estimation is minimized while ensuring the communication performance of the communication users, that is, the following optimization problem is solved: ; Analyze the problem and find it difficult to solve. Convert it into the following equivalent but easier to handle form: ; in is the auxiliary matrix, and then semidefinite relaxation is used to solve the transformed optimization problem. After semidefinite relaxation, the problem becomes: ; Here and They all represent the transmitted signal power. As auxiliary variables, relax it to , which is equivalent to the following linear matrix inequality: ; The final question turns into:

[0042] The transformed problem is a convex optimization problem, which can be solved directly using the CVX tool.

[0043] For details, please refer to Figure 3 - Figure 4 , the analysis method proposed in this technical solution is numerically simulated, and this technical solution is compared with the other two solutions. The results are as follows Figure 3 and Figure 4 As shown, the technical solution is referred to as "CI" in the figure, and the comparison scheme is a scheme in which the technical solution does not adopt CI, which is referred to as "COM" in the figure, and the other is a scheme in which the technical solution does not adopt CI. The scheme with all values ​​being 0 is represented by “SEN” in the figure. The “SEN” scheme represents the pursuit of ultimate perceptual performance. Figure 3 The relationship between the power budget and Cramer-Rao bound of the three schemes is described. Figure 3 It can be seen that under the same power budget, the CRB value of the "COM" scheme is the largest, the "CI" scheme is second, and the "SEN" scheme is the smallest, which is in line with expectations. Because the "CI" scheme introduces CI technology and relaxes the communication function constraints, its perception performance is better than that of the "COM" scheme under the same power constraint. The "SEN" scheme focuses on improving the perception performance without considering the communication performance. Therefore, it can obtain the smallest CRB value under the same power constraint, that is, it can obtain the best perception performance.

[0044] Figure 4 The relationship between the power budget and the achievable rate of the three schemes is described, among which the first scheme of the present invention The achievable rate of a communication user is expressed as: ; The other two options The achievable rate of a communication user is expressed as: ; The difference is that the "CI" scheme uses CI technology to convert multi-user interference into beneficial interference, so the communication rate of legitimate users does not include multi-user interference, while the "COM" scheme and the "SEN" scheme do not use CI technology, so there is multi-user interference. Figure 4 It can be seen that the achievable rate of the “CI” scheme is the highest, the achievable rate of the “COM” scheme is the second highest, and the achievable rate of the “SEN” scheme is the lowest.

[0045] pass Figure 3 , Figure 4 The comparison results show that among the three solutions, this technical solution can achieve a good level of communication performance while ensuring a certain level of perception performance.

[0046] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dual-base communication perception integrated beamforming design method based on interference utilization, characterized by: The steps include: Step 1: After the signal transmitted by the transmitting base station detects the sensing target, an echo signal is generated, which is received by the sensing base station. The sensing base station estimates the angle based on the echo signal and derives the Cramer-Rao bound of the angle estimation. Step 2: Introduce 16QAM constructive interference, and select the corresponding communication constraints under constructive interference according to the transmitted 16QAM signal; Step 3. According to the derived communication constraints based on constructive interference and the Cramer-Rao bound of angle estimation, a problem of minimizing the Cramer-Rao bound of angle estimation while ensuring communication performance is constructed. The original non-convex problem is transformed into a convex problem through a semidefinite relaxation method, and the CVX toolbox is used to solve it to obtain the optimal beamforming matrix.

2. According to claim 1, a dual-base communication perception integrated beamforming design method based on interference utilization is characterized in that: The scenario includes a transmitter station, a sensing base station, at least one downlink communication user and a sensing target. The 16QAM signal of a communication user is , No. The beamforming matrix of a communication user is , transmit signal for: ， Furthermore, the baseband signals sent to different communication users are independent of each other, and the baseband signals are known at the transmitting base station and the sensing base station.

3. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 2, characterized in that: set up and Corresponding to the angle of the target relative to the transmitting base station and the sensing base station, the sensing channel matrix of the transmitting base station via the sensing target to the sensing base station It is expressed as: ， in and are the receiving array response vector and the transmitting array response vector, respectively, It takes into account the path loss of the perceived target and the reflection coefficient of the radar scattering cross section. represents the conjugate transpose of a vector, Represents the transpose of a vector.

4. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 3 is characterized in that: The echo signal received by the sensing base station is: ； In the formula, for A noise vector, where each item has a mean of 0 and a variance of Additive white Gaussian noise in the perceptual channel; The unknown parameters in the sensing channel are given by Composition, of which , , the Fisher information matrix for estimating the unknown target parameters is expressed as: ； Where: Indicates vectorization of the received signal. represents taking the real part; In the matrix: ， ， ， Each entry in the matrix can be calculated as follows: ； So each entry in the matrix is: ， ； ， ； ， ； ， ； ， ； in, , express right Seeking guidance, express right Seeking guidance, ; The perceived CRB matrix is: ； estimate and The Cramero boundary is The diagonal elements of For estimation and The sum of Cramer-Rao bounds is used as a representation of perceptual performance.

5. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 4, characterized in that: No. The received signal at each user It is expressed as: ； in, Indicates the transmitting base station to the The channels of the communication users, The mean is 0 and the variance is The additive Gaussian white noise is Noise at each user.

6. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 5, characterized in that: Based on the 16QAM constellation diagram, it is divided into four parts, and their constructive interference is as follows: Ⅰ: For the four constellation points enclosed in the 16QAM constellation diagram, if the transmitted signal Corresponding to one of these four points, the constraint is: ； ； II: For the four constellation points on the upper and lower sides of the 16QAM constellation diagram close to the imaginary axis, the constructive area extends along the decision boundaries on the left and right sides of the constellation point away from the real axis. Corresponding to one of these four points, the constraint is: ； ； III: For the four constellation points on the left and right sides of the 16QAM constellation diagram close to the real axis, the constructive area extends along the decision boundaries on both sides of the constellation point away from the imaginary axis. Corresponding to one of these four points, the constraint is: ； ； IV: For the constellation points at the four outer vertices in the 16QAM constellation diagram, the constructive area extends infinitely away from the imaginary axis and the real axis. Corresponding to one of these four points, the constraint is: ； ； in, Indicates The noise-free received signal of each communication user is Indicates The threshold of the signal to interference plus noise ratio (SINR) of each communication user, The SINR of a communication user without CI is , after the introduction of CI, it becomes , and satisfy the corresponding conversion relationship; In the formula: Symbol Indicates that different symbols correspond to different quadrants. In the first quadrant, represent ; In the second quadrant, the real axis part represent , the imaginary axis part represent ; In the third quadrant, represent ; In the fourth quadrant, the real axis represent , the imaginary axis part represent .

7. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 6, characterized in that: The power constraint of the transmitted signal is: ； In the formula, Represents a given power budget.

8. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 7, characterized in that: The optimization problem solved after introducing CI is: ； Converting this into its equivalent form: ; in is the auxiliary matrix, tr(·) represents the trace of the matrix, which becomes: ； Here As auxiliary variables, relax it to , which is equivalent to the following linear matrix inequality: ； The final optimization problem is transformed into: ； The transformed optimization problem is a convex optimization problem, which is solved using the CVX tool.

9. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 8, characterized in that: It includes a transmitting base station, a sensing base station, at least one downlink communication user and a sensing target. The transmitting base station adopts the beamforming design method described in any one of claims 1 to 8 to transmit signals to communicate with the communication user and sense the target. The sensing base station is used to receive the target echo signal and perform angle estimation.

10. The method for designing dual-base communication perception integrated beamforming based on interference utilization according to claim 9, characterized in that: The transmitting base station is equipped with antennas, the sensing base station is equipped with antennas, and , the communication user is configured with a single antenna, and the sensing target is a stationary point object.

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