Transmitting beam forming method and system based on engineering simulation receiving and transmitting simultaneous array

Abstract

The invention discloses a transmitting beam forming method and system based on an engineering simulation transmitting and receiving simultaneous array, and the method comprises the steps: measuring the attenuator response and phase shifter response of a transmitting array of the transmitting and receiving simultaneous array, and constructing a transmitting and receiving simultaneous array beam forming weight lookup table; determining effective omnidirectional radiation power; presetting an inter-antenna coupling matrix of the simultaneous receiving and transmitting array, and constructing an optimization problem by combining the effective omnidirectional radiation power, the initial transmitting beam forming vector and the simultaneous receiving and transmitting array beam forming weight lookup table; and optimizing the initial transmitting beam forming vector based on the optimization problem to obtain an optimized target transmitting beam forming vector. According to the method, the wave beam weight can be optimized by considering the response of the real world simulation attenuator and the phase shifter, and the precision of the target emission wave beam forming vector is improved. The transmitting beam forming method and system based on the engineering simulation receiving and transmitting simultaneous array can be widely applied to the technical field of wireless communication.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and in particular to a transmit beamforming method and system based on an engineered simulated simultaneous transmit and receive array. Background Technology

[0002] Simultaneous transmit and receive technology, also known as in-band full-duplex technology, enables the synchronous transmission and reception of signals on the same frequency band, doubling spectrum utilization and greatly alleviating the scarcity of spectrum resources. A significant challenge of simultaneous transmit and receive technology is the strong self-interference caused by the transmitted signal. These self-interference signals can easily saturate the receiver, thus overwhelming the signal of interest. With continuous technological advancements, research on self-interference suppression has primarily focused on three dimensions: the propagation domain, the analog domain, and the digital domain. However, compared to digital domain methods, the isolation achieved by antenna and analog domain methods is relatively limited. Especially in large-scale phased arrays with strong self-interference due to multi-dimensional cross-coupling between the transmitter and receiver, RF cancellation adds significant costs to the system in terms of size, complexity, and power consumption. Beamforming is an efficient technique that can improve the spatial isolation of STAR phased arrays. Numerous studies have proposed various algorithms for different types of arrays, effectively achieving spatial isolation of self-interference signals. STAR phased arrays can be categorized into three beamforming architectures: digital beamforming, analog beamforming, and hybrid beamforming. Considering the cost of phased arrays, most real-world phased arrays use analog beamforming instead of digital beamforming, leading to errors in beamforming weight control. Summary of the Invention

[0003] To address the aforementioned technical problems, the present invention aims to provide a transmit beamforming method and system based on an engineered simulated simultaneous transmit and receive array, which can optimize beam weights by taking into account the responses of real-world simulated attenuators and phase shifters, thereby improving the accuracy of the target transmit beamforming vector.

[0004] The first technical solution adopted in this invention is: a transmit beamforming method based on an engineering-simulated simultaneous transmit and receive array, comprising the following steps:

[0005] Measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and construct a beamforming weight lookup table for the simultaneous transmit and receive array.

[0006] Obtain the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and determine the effective omnidirectional radiation power;

[0007] An optimization problem is constructed by presetting the antenna coupling matrix of the simultaneous transmit and receive array, combining the effective omnidirectional radiated power, the initial transmit beamforming vector, and the beamforming weight lookup table of the simultaneous transmit and receive array;

[0008] The initial transmit beamforming vector is optimized based on the optimization problem to obtain the optimized target transmit beamforming vector.

[0009] Furthermore, the step of measuring the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and constructing a beamforming weight lookup table for the simultaneous transmit and receive array, specifically includes:

[0010] Measure the attenuator and phase shifter responses of the transmit array in a simultaneous transmit and receive array;

[0011] The attenuator response and the phase shifter response are multiplied to calculate the weighted lookup table for simultaneous transmit and receive array beamforming.

[0012] The specific expression for the simultaneous transmit and receive array beamforming weight lookup table is as follows:

[0013]

[0014] In the above formula, This indicates a lookup table for selectable beamforming weights for simultaneous transmission and reception. This indicates the attenuator response of the array transmit component during simultaneous transmission and reception. N represents the phase shifter response of the simultaneous transmit and receive array component. a N represents the number of bits in the digitally controlled attenuator. p Indicates the number of bits in a numerically controlled phase shifter, [·] :,j Represents a matrix slice, (·) T This indicates the matrix transpose.

[0015] Furthermore, the step of obtaining the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and determining the effective omnidirectional radiated power, specifically includes:

[0016] Initialize the transmit beamforming vector to obtain the initial transmit beamforming vector;

[0017] Determine the desired beam pointing angle, obtain the steering vector of the transmitting array and the maximum single-link transmit power;

[0018] The effective omnidirectional radiation power is determined based on the desired beam pointing angle, the guiding vector of the transmitting array, and the initial transmitted beamforming vector.

[0019] Furthermore, the expression for determining the effective isotropic radiated power is specifically as follows:

[0020]

[0021] In the above formula, φ represents the azimuth angle in the spherical coordinate system, and θ represents the pitch angle in the spherical coordinate system. Indicates the transmitted beamforming vector. The guide vector of the transmitting array is represented by (·). H G represents the conjugate transpose of a matrix. t This indicates the radiation pattern of the transmitting array element.

[0022] Furthermore, the step of constructing an optimization problem by pre-setting the antenna coupling matrix of the simultaneous transmit and receive array, combining the effective omnidirectional radiated power, the initial transmit beamforming vector, and the beamforming weight lookup table of the simultaneous transmit and receive array, specifically includes:

[0023] Pre-set the inter-antenna coupling matrix of the array for simultaneous transmission and reception;

[0024] The self-interference signal power of the receiving array element is determined based on the antenna coupling matrix of the simultaneous transmitting and receiving array and the initial transmitted beamforming vector.

[0025] The gain pattern of the transmitting array is determined based on the effective omnidirectional radiated power, and the objective function is set in combination with the self-interference signal power of the receiving array element.

[0026] Obtain the total transmit power of the transmit array and set the first constraint condition;

[0027] The second constraint condition is set according to the simultaneous transmit and receive array beamforming weight lookup table;

[0028] Based on the first constraint, the second constraint, and the objective function, construct the optimization problem.

[0029] Furthermore, the step of pre-setting the inter-antenna coupling matrix of the simultaneous transmit and receive array specifically includes:

[0030] Obtain the propagation coefficient from the transmitting array to the receiving array element, the total number of transmitting links, and the total number of receiving links in the transmitting and receiving array simultaneously;

[0031] Based on the propagation coefficient, the total number of transmit links, and the total number of receive links, the antenna coupling matrix of the simultaneous transmit and receive array is preset;

[0032] The specific expression for the inter-antenna coupling matrix of the simultaneous transmit and receive array is as follows:

[0033]

[0034] In the above formula, S k,j J represents the propagation coefficient from transmitting element j to receiving element k, and J and K represent the total number of transmission and reception links, respectively.

[0035] Furthermore, the expression for determining the self-interference signal power of the receiving array element is as follows:

[0036]

[0037] In the above formula, This represents the power of the self-interference component at the receiving antenna. Let η represent the ideal inter-antenna coupling matrix of the simultaneous transmit and receive array. Diag(·) represents a function that takes the diagonal elements of the square matrix to form a vector or transforms a vector into a diagonal matrix. t This indicates the signal-to-noise ratio of the transmission link.

[0038] The specific expression for the optimization problem is as follows:

[0039]

[0040] In the above formula, formula (1) is the objective function of the optimization problem, which is to maximize the transmit pattern gain and minimize the self-interference signal power at each receiving element. The self-interference power in the denominator is the sum of the self-interference power at each receiving antenna. Formulas (2) and (3) are constraints. Formula (2) constrains that the transmit power of the transmit link does not exceed the maximum transmit power of a single link. Formula (3) constrains that the discrete value range of the simulated beamforming weight is within the lookup table.

[0041] Furthermore, the step of optimizing the initial transmit beamforming vector based on an optimization problem to obtain the optimized target transmit beamforming vector specifically includes:

[0042] By relaxing the optimization problem and removing the constraint on the discrete range of values ​​of the simulated beamforming weights, a solvable optimization problem is obtained.

[0043] By performing secondary optimization on a solvable optimization problem, a relaxed optimization problem is obtained;

[0044] Solve the relaxation optimization problem to obtain the upper bound of the optimization problem and the optimal solution of the transmitted beamforming vector;

[0045] The simultaneous transmit and receive array beamforming weight lookup table is divided with the optimal solution of the transmit beamforming vector to obtain the division result;

[0046] Based on the upper bound of the optimization problem, the phases of the division results are sorted, and the subspace containing the error between the phase and the optimal solution is retained within a preset range.

[0047] The amplitudes of the subspace are sorted, and the result with the amplitude closest to the optimal solution is retained as the optimization result. The optimized target transmission beamforming vector is then output.

[0048] The second technical solution adopted in this invention is: a transmit beamforming system based on an engineered simulated simultaneous transmit and receive array, comprising:

[0049] The first module is used to measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and to construct the beamforming weight lookup table of the simultaneous transmit and receive array.

[0050] The second module is used to obtain the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and to determine the effective omnidirectional radiation power.

[0051] The third module is used to pre-set the antenna coupling matrix of the simultaneous transmit and receive array, and combine the initial transmit beamforming vector with the beamforming weight lookup table of the simultaneous transmit and receive array to construct an optimization problem;

[0052] The fourth module is used to optimize the initial transmit beamforming vector based on an optimization problem, so as to obtain the optimized target transmit beamforming vector.

[0053] The beneficial effects of the method and system of this invention are as follows: This invention measures the attenuator and phase shifter responses of the transmit array in a simultaneous transmit / receive array, constructs a beamforming weight lookup table for the simultaneous transmit / receive array, uses a computer-controlled vector network analyzer and numerically controlled attenuators and phase shifters of the transmit components to measure the S-parameters of all attenuation and phase shift states, generates a lookup table of actual attenuation and phase shift at the operating frequency based on the measured S-parameters, optimizes self-interference suppression beamforming based on the lookup table, further obtains the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array in the simultaneous transmit / receive array, determines the effective omnidirectional radiation power, further pre-sets the inter-antenna coupling matrix of the simultaneous transmit / receive array, and combines the initial transmit beamforming vector with the transmit / receive weight lookup table. An optimization problem is constructed using a lookup table for beamforming weights in a time array. The optimization objectives are minimizing the maximum incident power of all receiving array elements and maximizing the transmit gain pattern. The constraints are the maximum transmit power of a single channel and the weights selected from the lookup table. This establishes an optimization problem for simulated beamforming. Finally, the initial transmit beamforming vector is optimized based on the optimization problem to obtain the optimized target transmit beamforming vector. The constraints of the optimization problem are relaxed, transforming it into an easily solvable form. Then, the subspace sorting search method is used to solve for the beamforming weight optimization result that satisfies all constraints. This method can consider the responses of attenuators and phase shifters in the real world to optimize the beam weights, thereby improving the accuracy of the target transmit beamforming vector. Attached Figure Description

[0054] Figure 1 This is a flowchart of the steps of the transmit beamforming method based on an engineered simulated simultaneous transmit and receive array of the present invention;

[0055] Figure 2 This is a structural block diagram of the transmit beamforming system based on an engineered simulated simultaneous transmit and receive array of the present invention;

[0056] Figure 3 This is a schematic diagram of the steps for beamforming in a specific embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of the simultaneous transmit and receive array structure and signal provided in a specific embodiment of the present invention;

[0058] Figure 5 This is the attenuator response provided in a specific embodiment of the present invention. Phase shifter response Schematic diagram of automatic measurement.

[0059] Figure 6 This is a schematic diagram of the amplitude of S21 of the transmission channel when the numerically controlled attenuator is controlled to have different attenuation values, according to a specific embodiment of the present invention.

[0060] Figure 7 This is a schematic diagram of the S21 phase of the transmission channel under different attenuation values ​​when the numerically controlled attenuator is controlled according to a specific embodiment of the present invention;

[0061] Figure 8 This is a schematic diagram of the S21 phase of the transmission channel under different phase shift values ​​when the numerically controlled phase shifter is controlled according to a specific embodiment of the present invention;

[0062] Figure 9 This is a schematic diagram of the amplitude of S21 of the transmission channel when the numerically controlled phase shifter is controlled to have different phase shift values, according to a specific embodiment of the present invention.

[0063] Figure 10 This is the automatic measurement attenuator response provided in a specific embodiment of the present invention. and phase shifter response A schematic diagram of the attenuation phase shift lookup table (amplitude) for the subsequently generated 7GHz transmit channel 1;

[0064] Figure 11 This is the automatic measurement attenuator response provided in a specific embodiment of the present invention. Phase shifter response A schematic diagram of the attenuation phase lookup table (phase) for the subsequently generated 7GHz transmit channel 1;

[0065] Figure 12 This is a schematic diagram of the maximum self-interference of all receiving antennas in all beam directions at different operating frequencies provided in a specific embodiment of the present invention;

[0066] Figure 13 This is a schematic diagram of the beam direction at -5° at different operating frequencies provided in a specific embodiment of the present invention;

[0067] Figure 14 This is a schematic diagram illustrating the standard deviation of the actual attenuator and phase shifter characteristics at different operating frequencies provided in a specific embodiment of the present invention;

[0068] Figure 15 This is a schematic diagram of the measured results of self-interference suppression beamforming provided in a specific embodiment of the present invention; Detailed Implementation

[0069] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The step numbers in the following embodiments are only for ease of explanation and do not limit the order of the steps. The execution order of each step in the embodiments can be adapted according to the understanding of those skilled in the art.

[0070] Before providing a detailed description of the embodiments of this application, some of the nouns and terms involved in the embodiments of this application will be explained first. The nouns and terms involved in the embodiments of this application are subject to the following interpretations.

[0071] 1) Simultaneous Transmit and Receive (STAR): A technique that transmits and receives electromagnetic wave signals at the same time and in the same frequency band within the same radio system. It is also known as in-band full-duplex (IBFD).

[0072] 2) Receive-Transmit(R / T) Isolation: This refers to the ratio of power coupled (leaked) from the transmit channel to the receive channel in an antenna duplexer, usually denoted by I. Receive-transmit isolation is a measure of power leakage from the transmit channel to the receive channel, equal to the ratio of the input power of the transmit channel to the power leaked into the receive channel, and its unit is usually expressed in dB.

[0073] 3) Self-Interference Cancellation (SIC): This refers to the process of suppressing strong self-interference signals from the transmitter using different methods in different parts of the system during simultaneous transmission and reception, including the propagation domain, analog domain, and digital domain. Self-interference cancellation is the key to achieving simultaneous transmission and reception technology.

[0074] 4) Adaptive Beamforming (ABF): This refers to the dynamic adjustment of the beamforming vector to adapt the transmit or receive beam to the actual channel environment and requirements. Its meaning is the same as beamforming optimization. In this embodiment of the invention, ABF before and after refers to adaptive transmit / receive beamforming optimization before and after.

[0075] In the current field of simultaneous transmit and receive array systems, the following main problems exist:

[0076] 1) Self-interference signals generated at the transmitting end can saturate the low-noise amplifier (LNA) at the receiving RF front end, generating a large number of nonlinear components, and can also saturate the receiving ADC, preventing the signal of interest from being received correctly.

[0077] 2) Simulated beamforming uses analog attenuators and phase shifters to control the weight of beamforming, but the accuracy of analog attenuators and phase shifters is limited, which leads to a decrease in the performance of self-interference suppression.

[0078] 3) The attenuation step and inherent phase shift of the real-world analog attenuator are different under different attenuation states and operating frequencies. The phase shift step and inherent attenuation of the real-world analog phase shifter are different under different phase shift states and operating frequencies, which leads to errors in the control of beamforming weights.

[0079] Based on this, this invention proposes an engineering-based method for implementing transmit beamforming in a simulated simultaneous transmit and receive array. It considers the responses of real-world simulated attenuators and phase shifters to optimize beam weights, demonstrating high engineering practicality. First, a computer-controlled vector network analyzer and numerically controlled attenuators and phase shifters of the transmit component are used to measure the S-parameters of all attenuation and phase shift states. A lookup table of actual attenuation and phase shifts at the operating frequency is generated based on the measured S-parameters. Self-interference suppression beamforming is then optimized using this lookup table. With minimizing the maximum incident power of all receiving array elements and maximizing the transmit gain pattern as optimization objectives, and the maximum transmit power and weights of a single channel selected from the lookup table as constraints, an optimization problem for simulated beamforming is established. Since this optimization problem is non-convex and difficult to solve, this invention relaxes the constraints, transforming the optimization problem into an easily solvable form. Then, a subspace sorting search method is used to solve for the optimized beamforming weights that satisfy all constraints.

[0080] Reference Figure 1 This invention provides a transmit beamforming method based on an engineered simulated simultaneous transmit and receive array, the method comprising the following steps:

[0081] S100. Measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and construct a beamforming weight lookup table for the simultaneous transmit and receive array.

[0082] First, it needs to be explained that, as Figure 4As shown, to meet the requirements of high isolation and long-distance sensing or communication scenarios in simultaneous transmit / receive arrays, this invention provides an engineered method for simulating transmit beamforming in a simultaneous transmit / receive array. The aim is to reduce the impact of errors in real-world analog attenuators and phase shifters, and by optimizing transmit beamforming, improve the spatial isolation between the transmit and receive arrays in a simultaneous transmit / receive phased array, preventing saturation of the low-noise amplifier and analog-to-digital converter at the receiver. The simultaneous transmit / receive array system is an analog array architecture without a reference link. The transmit RF link includes an analog-to-digital converter, up-converter, power amplifier, power divider, digitally controlled attenuator, and digitally controlled phase shifter; the receive link includes a low-noise amplifier, digitally controlled attenuator, digitally controlled phase shifter, combiner, down-converter, power amplifier, and analog-to-digital converter, etc. Figure 4 As shown. The function of the digital-to-analog converter (DAC) is to convert the intermediate frequency (IF) digital signal into an IF analog signal. The up-conversion function multiplies the IF analog signal with the local oscillator signal, up-converting it to the transmission frequency band. The power amplifier amplifies the signal power. The power divider divides the transmitted signal into multiple signals of equal power. The digitally controlled attenuator controls the amplitude of the beamforming weights. The digitally controlled phase shifter controls the phase of the beamforming weights. The low-noise amplifier amplifies the received signal while reducing the noise figure of the receiver link. The combiner combines multiple received signals into a single signal. The down-conversion function multiplies the RF received signal with the local oscillator signal, down-converting it to the IF frequency. The analog-to-digital converter (ADC) converts the IF analog signal into an IF digital signal.

[0083] exist Figure 4 In the process, the transmitted signal passes through a digital-to-analog converter, up-converter, power amplifier, J-channel power divider, digitally controlled attenuator, digitally controlled phase shifter, and power amplifier, and is then superimposed with Gaussian white noise n from the transmitting antenna. t After (n), the transmitting antenna signal t(n) is obtained. After passing through the self-interference channel, it generates interference at the receiving antenna. The receiving antenna signal contains the self-interference signal and the signal of interest s(n). The signal passes through the low-noise amplifier, digitally controlled attenuator, digitally controlled phase shifter, combiner, down-converter, power amplifier, analog-to-digital converter, etc. in the receiving link to obtain the received digital signal y(n).

[0084] S110. Measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array;

[0085] Specifically, attenuator response Phase shifter response Measurements were obtained by simultaneously controlling a vector network analyzer and a transmitter module using a computer. A measurement diagram is shown below. Figure 5 As shown, the attenuator response of the array transmit component is measured simultaneously with the transmit and receive operations. Phase shifter response Includes the following steps:

[0086] 1) Initialize parameter settings on the computer;

[0087] 2) The two ports of the vector network analyzer are connected to the input channel and one of the output channels of the transmitting component, respectively;

[0088] 3) Connect the vector network analyzer via Ethernet and set the measurement parameters;

[0089] 4) Connect the transmitting component using a serial port;

[0090] 5) Computer-controlled attenuator and phase shifter of the transmitting assembly;

[0091] 6) The computer triggers the vector network analyzer via Ethernet to perform frequency sweep measurements;

[0092] 7) After the vector network analyzer completes the frequency sweep, save the S-parameters to your local computer;

[0093] 8) Repeat steps 5), 6), and 7) until the status of all CNC attenuators and CNC phase shifters has been measured;

[0094] 9) Change the output channel of the transmitting component and repeat the above measurement operation until all transmitting channels have been measured.

[0095] Among them, the attenuator response of the simultaneous transmit and receive array component Phase shifter response The S-parameters of each attenuation and phase shift step of the attenuator and phase shifter in each channel of the transmitting component are defined as:

[0096]

[0097] In the above formula, It is the number of bits in the digitally controlled attenuator. It refers to the number of bits in the CNC phase shifter. This represents the number of transmission links.

[0098] In some specific embodiments, the number of bits of the digitally controlled attenuator The attenuation interval is 0.5dB; the number of bits in the CNC phase shifter is... The phase shift interval is 5.625°, and the states of the digitally controlled attenuator are as follows: Types of numerically controlled phase shifters have various states. For this type of measurement, there are 8 transmission channels, and a total of (64+64)×8=1024 S-parameters need to be measured.

[0099] S120. Perform product calculation on the attenuator response and phase shifter response, and construct a simultaneous transmit and receive array beamforming weight lookup table.

[0100] Specifically, it is assumed that the numerically controlled attenuator and numerically controlled phase shifter on the same link will not affect each other due to different attenuation and phase shifts. During transmission and reception, a certain state element of the array beamforming weight lookup table is equal to the product of the S-parameters of the numerically controlled attenuator and phase shifter in the corresponding state.

[0101] Simultaneous transmit and receive array selectable beamforming weight lookup table Defined as all possible values ​​of the simulated beamforming weights, it is a three-dimensional complex matrix, i.e.:

[0102]

[0103] This invention assumes that digitally controlled attenuators and digitally controlled phase shifters on the same link will not affect each other due to their different attenuation and phase shifts. Therefore, the expression for the simultaneous transmit and receive array beamforming weight lookup table is as follows:

[0104]

[0105] In the above formula, This indicates a lookup table for selectable beamforming weights for simultaneous transmission and reception. This indicates the attenuator response of the array transmit component during simultaneous transmission and reception. N represents the phase shifter response of the simultaneous transmit and receive array component. a N represents the number of bits in the digitally controlled attenuator. p Indicates the number of bits in a numerically controlled phase shifter, [·] :,j Represents a matrix slice, (·) T This indicates the matrix transpose.

[0106] S200: Obtain the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and determine the effective omnidirectional radiation power;

[0107] S210. Initialize the transmit beamforming vector to obtain the initial transmit beamforming vector;

[0108] S220. Determine the desired beam pointing angle, obtain the steering vector of the transmitting array and the maximum single-link transmit power;

[0109] S230. Determine the effective omnidirectional radiation power based on the desired beam pointing angle, the guiding vector of the transmitting array, and the initial transmitting beamforming vector.

[0110] The specific expression for determining the effective isotropic radiated power is as follows:

[0111]

[0112] In the above formula, φ represents the azimuth angle in the spherical coordinate system, and θ represents the pitch angle in the spherical coordinate system. Indicates the transmitted beamforming vector. The guide vector of the transmitting array is represented by (·). H G represents the conjugate transpose of a matrix. t This indicates the radiation pattern of the transmitting array element.

[0113] S300, the pre-set antenna coupling matrix of the simultaneous transmit and receive array, combined with the effective omnidirectional radiated power, the initial transmit beamforming vector and the beamforming weight lookup table of the simultaneous transmit and receive array, to construct an optimization problem;

[0114] S310, Preset the inter-antenna coupling matrix of the simultaneous transmit and receive array;

[0115] Specifically, the propagation coefficient, total number of transmission links, and total number of reception links of the transmitting array to the receiving array elements in the simultaneous transmitting and receiving array are obtained; based on the propagation coefficient, total number of transmission links, and total number of reception links, the inter-antenna coupling matrix of the simultaneous transmitting and receiving array is preset.

[0116] The specific expression for the inter-antenna coupling matrix of the simultaneous transmit and receive array is as follows:

[0117]

[0118] In the above formula, S k,j J represents the propagation coefficient from transmitting element j to receiving element k, and J and K represent the total number of transmission and reception links, respectively.

[0119] In some specific embodiments, the number of transmit and receive links J=8 and K=4 in this embodiment of the invention. Therefore, the ideal inter-antenna coupling matrix of the simultaneous transmit and receive array is a complex matrix of 4 rows and 8 columns, i.e. In the embodiments of the present invention, the propagation coefficients of each pair of transmit-to-receive antennas in the ideal transmit-receive antenna coupling matrix of the simultaneous transmit-receive array are obtained through HFSS simulation.

[0120] S320. Determine the self-interference signal power of the receiving array element based on the antenna coupling matrix of the simultaneous transmitting and receiving array and the initial transmitted beamforming vector.

[0121] Specifically, the expression for determining the self-interference signal power of the receiving array element is as follows:

[0122]

[0123] In the above formula, This represents the power of the self-interference component at the receiving antenna. Let η represent the ideal inter-antenna coupling matrix of the simultaneous transmit and receive array. Diag(·) represents a function that takes the diagonal elements of the square matrix to form a vector or transforms a vector into a diagonal matrix. t This indicates the signal-to-noise ratio of the transmission link.

[0124] S330. Determine the gain pattern of the transmitting array based on the effective omnidirectional radiation power, and set the objective function in conjunction with the self-interference signal power of the receiving array elements.

[0125] S340. Obtain the total transmit power of the transmit array and set the first constraint condition;

[0126] S350. Set the second constraint condition according to the simultaneous transmit and receive array beamforming weight lookup table.

[0127] S360. Based on the first constraint, the second constraint, and the objective function, construct the optimization problem.

[0128] Specifically, the expression for the optimization problem is as follows:

[0129]

[0130] In the above formula, formula (1) is the objective function of the optimization problem, which is to maximize the transmit pattern gain and minimize the self-interference signal power at each receiving element. The self-interference power in the denominator is the sum of the self-interference power at each receiving antenna. Formulas (2) and (3) are constraints. Formula (2) constrains that the transmit power of the transmit link does not exceed the maximum transmit power of a single link. Formula (3) constrains that the discrete value range of the simulated beamforming weight is within the lookup table.

[0131] The expression for the equivalent self-interference noise covariance matrix is ​​as follows:

[0132]

[0133] In the above formula, P t,m Indicates the maximum transmit power that a single transmit link can withstand, |·| 2 It represents the square of the modulus of a complex number.

[0134] S400. Based on the optimization problem, the initial transmit beamforming vector is optimized to obtain the optimized target transmit beamforming vector.

[0135] S410. Relax the optimization problem to remove the constraint on the discrete range of simulated beamforming weights, and obtain a solvable optimization problem.

[0136] S420. Perform secondary optimization on the solvable optimization problem to obtain a relaxed optimization problem;

[0137] S430. Solve the relaxation optimization problem to obtain the upper bound of the optimization problem and the optimal solution of the transmitted beamforming vector;

[0138] Specifically, by relaxing the optimization problem P1 and removing the constraint on the discrete range of the simulated beamforming weights, a solvable optimization problem P2 is obtained, whose expression is:

[0139]

[0140] The objective function of optimization problem P2 is in the form of the generalized Rayleigh quotient, which can be maximized. Further simplifying optimization problem P2, we get P3, whose expression is:

[0141]

[0142] Here, γ is the regularization coefficient, which controls the degree of self-interference suppression in the algorithm and the reduction in transmit pattern gain compared to uniform beamforming.

[0143] Solve the relaxed optimization problem P3 to obtain the upper bound of the optimization problem and the optimal solution b of the transmitted beamforming vector. t * Then, the subspace sorting search method is used to solve the final solution of the optimization problem that satisfies the discrete value constraints of the analog attenuator and phase shifter.

[0144] S440. Divide the simultaneous transmit and receive array beamforming weight lookup table with the optimal solution of the transmit beamforming vector to obtain the division result.

[0145] S450. Based on the upper bound of the optimization problem, sort the phases of the division results and retain the subspace where the error between the phase and the optimal solution is within a preset range.

[0146] S460. Sort the amplitudes of the subspace, retain the result whose amplitude is closest to the optimal solution as the optimization result, and output the optimized target transmission beamforming vector.

[0147] Specifically, the beamforming weight lookup table formed by the measured simulated attenuator phase shifter is divided by the optimal solution of the transmitted beamforming vector; the phases of the division results are sorted, and the subspaces whose phase errors with the optimal solution are within a certain range are retained; then the amplitudes of the subspaces are sorted, and the results whose amplitudes are closest to the optimal solution are retained as the optimization results.

[0148] In some specific embodiments, the transmit beamforming weight is defined as:

[0149]

[0150]

[0151] Among them, P t,m The maximum transmit power that a single transmit link can withstand, |·| 2 It is the square of the modulus of the complex number.

[0152] Specifically, the dimension of the transmit beamforming vector in this embodiment of the invention is 8×1, and the maximum transmit power of a single transmit link is 100W.

[0153] Furthermore, the effective isotropic radiated power of the transmitting array is defined as follows:

[0154] EIRP(φ,θ)=PtGt(φ,θ)

[0155] Among them, P t G represents the total transmit power of the transmitting array. t φ represents the transmit array gain; φ represents the azimuth angle in spherical coordinates; θ represents the elevation angle in spherical coordinates.

[0156] Furthermore, the total transmission power in this embodiment of the invention is:

[0157]

[0158] Therefore, the calculation of effective isotropic radiated power can be transformed into:

[0159]

[0160] Among them, b t Weighting is applied to the transmitted beam. H Represents the conjugate transpose of a matrix; g t The radiation pattern of the transmitting array element can be obtained from HFSS simulation. The steering vector of the transmitting array is expressed as:

[0161]

[0162] Where λ is the signal wavelength, x t and y t These are the x and y coordinates of the position of the array element.

[0163] Furthermore, the self-interference power of the receiving element of the simultaneous transmit and receive array is defined to reflect the self-interference isolation performance after beam optimization. By providing the signal flow graph of the simultaneous transmit and receive array, the expression of the incident signal arriving at the receiving element is determined; and the self-interference component power is calculated using the incident signal expression.

[0164] The signal flow diagram of the simultaneous transmit and receive array in this embodiment of the invention is as follows: Figure 3 The expression for the incident signal of the receiving array element is:

[0165] r(n) = Mb t x(n)+Mn t (n)+s(n)

[0166] Where x(n) is the signal to be transmitted, with a power of 1, i.e., E[|x(n)| 2 ] = 1. n t (n) represents the emitted noise. s(n) is the signal of interest at the receiving array element.

[0167] Specifically, using the incident signal expression, the power of the self-interference component at the receiving antenna is:

[0168]

[0169] Among them, the self-interference component power at the receiving antenna The function Diag(·) is defined as taking the diagonal elements of a square matrix to form a vector or converting a vector into a diagonal matrix, η t This represents the signal-to-noise ratio of the transmission link.

[0170] Furthermore, due to The power of the self-interference component at the receiving antenna can be rewritten as:

[0171]

[0172] Among them, M bt,k It is the equivalent self-interference noise covariance matrix, expressed as:

[0173]

[0174] The optimization of the transmitted beamforming vector includes: determining the optimization objective; determining the constraints; establishing an optimization problem model based on the optimization objective and constraints; and solving the optimization problem.

[0175] Specifically, the optimization objective is determined to maximize the gain of the transmit pattern of interest while minimizing the self-interference signal power of each receive antenna. The expression for the optimization objective can be written as:

[0176]

[0177] The constraints are defined, including: constraint 1, which is the maximum transmit power that a single transmit link can withstand; and constraint 2, which is that beamforming weights can only be selected from a lookup table.

[0178] Among them, taking the maximum transmit power that a single transmit link can withstand as constraint condition 1, it can be written as:

[0179] |b t,j | 2 ≤P t,m j = 1, 2, ..., J

[0180] Among them, constraint 2, which stipulates that beamforming weights can only take values ​​from the lookup table, can be written as:

[0181]

[0182] Specifically, based on the optimization objective and constraints, an optimization problem model is established, namely:

[0183]

[0184] The first line represents the objective function of the optimization problem, which is to maximize the transmit pattern gain and minimize the self-interference signal power at each receiver element. The self-interference power in the denominator is the sum of the self-interference power at each receiver antenna. The second and third lines represent the constraints. The second line constrains the transmit power of the transmit link to not exceed the maximum transmit power of a single link, and the third line constrains the discrete values ​​of the simulated beamforming weights to be within the lookup table.

[0185] However, optimization problem P1 is a non-convex problem and difficult to solve because the decision variables are discrete. Therefore, by relaxing optimization problem P1 and removing the constraint of the discrete range of simulated beamforming weights, a solvable optimization problem P2 is obtained:

[0186]

[0187] st|b t,j | 2 ≤P t,m j = 1, 2, ..., J

[0188] Since the objective function of optimization problem P2 is b t The generalized Rayleigh quotient, which can be maximized, allows the optimization problem P2 to be further simplified to:

[0189]

[0190] Here, γ is the regularization coefficient, which controls the degree of self-interference suppression and transmit pattern gain reduction in the algorithm. When the value of γ is large, the degree of self-interference suppression is low, and the transmit pattern gain reduction is less compared with uniform beamforming; when the value of γ is small, the degree of self-interference suppression is large, and the transmit pattern gain reduction is also larger compared with uniform beamforming.

[0191] Furthermore, by solving the relaxed optimization problem P3, we obtain the upper bound of the optimization problem and the optimal solution b of the transmitted beamforming vector. t *Then, the subspace sorting search method is used to solve the final solution of the optimization problem that satisfies the discrete value constraints of the simulated attenuator and phase shifter. The process of the subspace sorting search method is as follows: the measured beamforming weights formed by the simulated attenuator and phase shifter are used to look up the table. The beamforming weights are divided by the optimal solution of the transmitted beamforming vector. The phases of the division results are then sorted, retaining subspaces where the phase error with the optimal solution is within a certain range. The amplitudes of these subspaces are then sorted, and the result closest to the optimal solution is retained as the optimized result. Since the phase of the beamforming weights significantly affects self-interference suppression and the synthetic pattern gain, the sorting search method first limits the phase error and then sorts the amplitudes, ensuring that the phase error does not exceed a certain value.

[0192] Furthermore, the optimized beamforming vector is multiplied by the steering vector to construct the transmit beam in the target direction. Based on the optimized beamforming vector, the self-interference signal power before and after beam optimization is calculated using the self-interference component power expression.

[0193] like Figure 6 as well as Figure 7 As shown, to control the amplitude and phase of S21 of the transmission channel under different attenuation values ​​of the digitally controlled attenuator, taking transmission channel 1 as an example, port 1 of the vector network analyzer is connected to the input of the 8-way power divider of the transmission component 1, and port 2 is connected to the output of the power divider, digitally controlled phase shifter, digitally controlled attenuator and power amplifier. Figure 6 The display shows the S21 amplitude of the transmission channel under different attenuation values ​​of the digitally controlled attenuator. It can be seen that the S21 amplitude of the attenuator gradually decreases with control, and the attenuation control interval is about 0.5dB. However, the actual attenuation interval of the attenuator has errors, with some intervals being greater than 0.5dB and some intervals being less than 0.5dB. Figure 7 The S21 phase of the transmit channel is shown when the digitally controlled attenuator has different attenuation values. It can be seen that in some frequency bands, such as 12-18GHz, the additional phase of the attenuator varies greatly under different attenuation values.

[0194] like Figure 8 as well as Figure 9 The figure shows the phase and amplitude of S21 in the transmit channel when the numerically controlled phase shifter is set to different phase shift values. Experimental setup and... Figure 6 as well as Figure 7 same. Figure 8 The display shows the S21 phase of the transmission channel under different phase shift values ​​of the CNC phase shifter. It can be seen that the S21 phase of the phase shifter gradually moves with the control. The theoretical phase shift control interval is about 5.625°, but the actual phase shift interval error is large. Figure 9The display shows the S21 amplitude of the transmit channel with different phase shift values ​​for the digitally controlled phase shifter. It can be seen that at certain frequency points, the additional attenuation of the phase shifter differs with different phase shift values, with a difference of approximately 1 dB. (Summary) Figure 6 , Figure 7 , Figure 8 as well as Figure 9 The experiment shows that due to the imperfections in the characteristics of actual attenuators and phase shifters, the weight control of simulated beamforming is easily affected.

[0195] like Figure 10 as well as Figure 11 The image shows the response of the automatically measured attenuator. Phase shifter response The attenuation and phase shift lookup table for the 7GHz transmit channel 1 was subsequently generated. Based on the actual measured lookup table, the optimized beamforming weights were generated, taking into account the imperfections of the actual numerically controlled attenuators and phase shifters, as well as the amplitude and phase inconsistencies between channels (when both the attenuator and phase shifter are at 0, the measured response is the inherent response of the channel), making the simulated beamforming self-interference suppression more practical.

[0196] like Figure 12 as well as Figure 13 As shown, Figure 12 The maximum self-interference of all receiving antennas in all beam directions at different operating frequencies. Figure 13 The beam patterns at -5° for different operating frequencies were compared with uniform beamforming, traditional analog beamforming methods that directly quantize without considering actual attenuation phase shifter characteristics, and the method of this invention. Simulations were performed at frequencies of 6 GHz, 7 GHz, 9 GHz, 15 GHz, and 18 GHz. The results show that the method of this invention considers the actual attenuation phase shifter characteristics. Compared with uniform beamforming, the maximum self-interference of all receiving antennas in all beam directions at different operating frequencies is reduced most at 6 GHz (26.12 dB) and least at 18 GHz (19 dB). Compared with the traditional directly quantized analog beamforming method, the self-interference power at 7 GHz remains basically the same, while the self-interference power at other frequencies is reduced, with the largest reduction at 18 GHz (6.61 dB). The method presented in this paper has a transmit pattern gain that is basically consistent with that of traditional analog beamforming methods. Compared with uniform beamforming, the transmit pattern gain is reduced by about 5dB. This is because in the beamforming self-interference suppression algorithm, self-interference power and transmit pattern are a pair of contradictory quantities. When the degree of self-interference suppression is large, the transmit pattern gain will inevitably decrease.

[0197] Figure 14 The standard deviation of the actual attenuator and phase shifter characteristics at different operating frequencies. Figure 14In the figure, (a) represents the maximum phase standard deviation of the attenuator under all attenuation and phase shift control conditions for all transmission channels at different operating frequencies. Figure 14 (b) represents the maximum phase standard deviation of the phase shifter phase shift interval under all attenuation phase shift control conditions for all transmit channels at different operating frequencies. Figure 14 In the figure, (c) represents the maximum amplitude standard deviation of the attenuation interval of the attenuator under all attenuation phase shift control conditions for all transmit channels at different operating frequencies. Figure 14 In the figure, (d) represents the maximum amplitude standard deviation of the phase shifter under all attenuation phase shift control conditions for all transmit channels at different operating frequencies. This result explains, to some extent, the... Figure 12 as well as Figure 13 The results show that at a working frequency of 7 GHz, the standard deviation of the attenuator phase shifter characteristics is small, indicating that the actual characteristics of the attenuator phase shifter are close to the ideal situation. In this case, the method in this paper does not improve upon the traditional method. However, when the standard deviation of the attenuator phase shifter characteristics is large, it indicates that the actual characteristics of the attenuator phase shifter deviate significantly from the ideal situation. In this case, the method of this invention shows a significant improvement compared to the traditional method.

[0198] Finally, as Figure 15 The figure shows the experimental results of self-interference suppression beamforming. Uniform beamforming (CBF) at 7 GHz with beam pointing to 0 was measured, along with the self-interference signal power of each receiving antenna using the proposed method. Experimental results show that the beamforming method proposed in this invention effectively achieves self-interference suppression. In the actual measurements, the largest reduction in self-interference signal power was achieved at antenna 1, a reduction of 19.2 dB. The worst suppression was observed at receiving antenna 2, with a self-interference signal power reduction of 14.44 dB.

[0199] In summary, as Figure 3 As shown in the embodiment of the present invention, an engineering simulation method for transmitting and receiving simultaneously arrays is provided, comprising: determining the configuration parameters of the transmitting and receiving simultaneously array system, wherein determining the configuration parameters of the transmitting and receiving simultaneously array system includes determining the number of transmitting and receiving links of the transmitting and receiving simultaneously array system; determining the distribution shape parameters of the transmitting and receiving simultaneously array; determining the element spacing parameters of the transmitting and receiving simultaneously array system; determining the scanning range of the main beam of the transmitting and receiving simultaneously array system; determining the center frequency of the transmitting and receiving simultaneously array system; the transmitting and receiving simultaneously array is an 8-transmit 4-receive uniform linear array, and the elements adopt coaxially fed helical antennas.

[0200] Further define the ideal inter-antenna coupling matrix M of the simultaneous transmit / receive array; define the attenuator response of the transmit component of the simultaneous transmit / receive array. and phase shifter response Define a simultaneous transmit and receive array beamforming weight lookup table Define the transmit beamforming weight b in a simultaneous transmit and receive array.t The following parameters are defined as optimization items: The effective omnidirectional radiation power of the transmitting array is defined to reflect the transmission pattern after beam optimization; the self-interference power of the receiving elements of the array during transmission and reception is defined to reflect the self-interference isolation performance after beam optimization; the transmitting beamforming vector is optimized; and the transmitting beam in the target direction is constructed based on the optimized beamforming vector. The self-interference signal power before and after beam optimization is calculated based on the optimized beamforming vector.

[0201] Reference Figure 2 A transmit beamforming system based on an engineered simulated simultaneous transmit and receive array includes:

[0202] The first module 201 is used to measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and to construct a beamforming weight lookup table for the simultaneous transmit and receive array.

[0203] The second module 202 is used to obtain the initial transmit beamforming vector, steering vector and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and to determine the effective omnidirectional radiation power;

[0204] The third module 203 is used to pre-set the antenna coupling matrix of the simultaneous transmit and receive array, and to construct an optimization problem by combining the initial transmit beamforming vector and the beamforming weight lookup table of the simultaneous transmit and receive array.

[0205] The fourth module 204 is used to optimize the initial transmit beamforming vector based on an optimization problem, so as to obtain the optimized target transmit beamforming vector.

[0206] The content of the above method embodiments is applicable to this system embodiment. The specific functions implemented in this system embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.

[0207] The above is a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A transmit beamforming method based on an engineering-simulated simultaneous transmit and receive array, characterized in that, Includes the following steps: Measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and construct a beamforming weight lookup table for the simultaneous transmit and receive array. Obtain the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and determine the effective omnidirectional radiation power; An optimization problem is constructed by pre-setting the antenna coupling matrix of the simultaneous transmit and receive array, combining the effective omnidirectional radiated power, the initial transmit beamforming vector, and the beamforming weight lookup table of the simultaneous transmit and receive array; The initial transmit beamforming vector is optimized based on the optimization problem to obtain the optimized target transmit beamforming vector.

2. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 1, characterized in that, The step of measuring the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and constructing the beamforming weight lookup table for the simultaneous transmit and receive array, specifically includes: Measure the attenuator and phase shifter responses of the transmit array in a simultaneous transmit and receive array; The attenuator response and the phase shifter response are multiplied to calculate the weighted lookup table for simultaneous transmit and receive array beamforming. The specific expression for the simultaneous transmit and receive array beamforming weight lookup table is as follows: In the above formula, This indicates a lookup table for selectable beamforming weights for simultaneous transmission and reception. This indicates the attenuator response of the array transmit component during simultaneous transmission and reception. N represents the phase shifter response of the simultaneous transmit and receive array component. a N represents the number of bits in the digitally controlled attenuator. p Indicates the number of bits in a numerically controlled phase shifter, [·] :,j Represents a matrix slice, (·) T This indicates the matrix transpose.

3. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 2, characterized in that, The step of obtaining the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and determining the effective omnidirectional radiated power, specifically includes: Initialize the transmit beamforming vector to obtain the initial transmit beamforming vector; Determine the desired beam pointing angle, obtain the steering vector of the transmitting array and the maximum single-link transmit power; The effective omnidirectional radiation power is determined based on the desired beam pointing angle, the guiding vector of the transmitting array, and the initial transmitted beamforming vector.

4. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 3, characterized in that, The specific expression for determining the effective isotropic radiated power is as follows: In the above formula, φ represents the azimuth angle in the spherical coordinate system, and θ represents the pitch angle in the spherical coordinate system. Indicates the transmitted beamforming vector. The guide vector of the transmitting array is represented by (·). H G represents the conjugate transpose of a matrix. t This indicates the radiation pattern of the transmitting array element.

5. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 4, characterized in that, The step of constructing the optimization problem by pre-setting the inter-antenna coupling matrix of the simultaneous transmit and receive array, combining the effective omnidirectional radiated power, the initial transmit beamforming vector, and the beamforming weight lookup table of the simultaneous transmit and receive array, specifically includes: Pre-set the inter-antenna coupling matrix of the array for simultaneous transmission and reception; The self-interference signal power of the receiving array element is determined based on the antenna coupling matrix of the simultaneous transmitting and receiving array and the initial transmitted beamforming vector. The gain pattern of the transmitting array is determined based on the effective omnidirectional radiated power, and the objective function is set in combination with the self-interference signal power of the receiving array element. Obtain the total transmit power of the transmit array and set the first constraint condition; The second constraint condition is set according to the simultaneous transmit and receive array beamforming weight lookup table; Based on the first constraint, the second constraint, and the objective function, construct the optimization problem.

6. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 5, characterized in that, The step of presetting the inter-antenna coupling matrix of the simultaneous transmit and receive array specifically includes: Obtain the propagation coefficient from the transmitting array to the receiving array element, the total number of transmitting links, and the total number of receiving links in the transmitting and receiving array simultaneously; Based on the propagation coefficient, the total number of transmit links, and the total number of receive links, the antenna coupling matrix of the simultaneous transmit and receive array is preset; The specific expression for the inter-antenna coupling matrix of the simultaneous transmit and receive array is as follows: In the above formula, S k,j J represents the propagation coefficient from transmitting element j to receiving element k, and J and K represent the total number of transmission and reception links, respectively.

7. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 6, characterized in that, The specific expression for determining the self-interference signal power of the receiving array element is as follows: In the above formula, This represents the power of the self-interference component at the receiving antenna. Let η represent the ideal inter-antenna coupling matrix of the simultaneous transmit and receive array. Diag(·) represents a function that takes the diagonal elements of the square matrix to form a vector or transforms a vector into a diagonal matrix. t This indicates the signal-to-noise ratio of the transmission link.

8. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 7, characterized in that, The specific expression for the optimization problem is as follows: In the above formula, formula (1) is the objective function of the optimization problem, which is to maximize the transmit pattern gain and minimize the self-interference signal power at each receiving element. The self-interference power in the denominator is the sum of the self-interference power at each receiving antenna. Formulas (2) and (3) are constraints. Formula (2) constrains that the transmit power of the transmit link does not exceed the maximum transmit power of a single link. Formula (3) constrains that the discrete value range of the simulated beamforming weight is within the lookup table.

9. The transmit beamforming method based on an engineered simulated simultaneous transmit and receive array according to claim 8, characterized in that, The step of optimizing the initial transmit beamforming vector based on an optimization problem to obtain the optimized target transmit beamforming vector specifically includes: By relaxing the optimization problem and removing the constraint on the discrete range of values ​​of the simulated beamforming weights, a solvable optimization problem is obtained. By performing secondary optimization on a solvable optimization problem, a relaxed optimization problem is obtained; Solve the relaxation optimization problem to obtain the upper bound of the optimization problem and the optimal solution of the transmitted beamforming vector; The simultaneous transmit and receive array beamforming weight lookup table is divided with the optimal solution of the transmit beamforming vector to obtain the division result; Based on the upper bound of the optimization problem, the phases of the division results are sorted, and the subspace containing the error between the phase and the optimal solution is retained within a preset range. The amplitudes of the subspace are sorted, and the result with the amplitude closest to the optimal solution is retained as the optimization result. The optimized target transmission beamforming vector is then output.

10. A transmit beamforming system based on an engineered simulated simultaneous transmit and receive array, characterized in that, Includes the following modules: The first module is used to measure the attenuator response and phase shifter response of the transmit array of the simultaneous transmit and receive array, and to construct the beamforming weight lookup table of the simultaneous transmit and receive array. The second module is used to obtain the initial transmit beamforming vector, steering vector, and maximum single-link transmit power of the transmit array of the simultaneous transmit and receive array, and to determine the effective omnidirectional radiation power. The third module is used to pre-set the antenna coupling matrix of the simultaneous transmit and receive array, and combine the initial transmit beamforming vector with the beamforming weight lookup table of the simultaneous transmit and receive array to construct an optimization problem; The fourth module is used to optimize the initial transmit beamforming vector based on an optimization problem, so as to obtain the optimized target transmit beamforming vector.

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