Active array multi-channel calibration method and system based on quadrature phase shift modulation

Abstract

The application provides a kind of active array multichannel calibration method and system based on quadrature phase shift modulation, it is related to radar detection technical field, including the following steps: active array is placed in wave-absorbing darkroom or outdoor open area, a calibration signal source is placed in the position that is directly opposite active array and the vertical distance with active array is set distance R;Calibration signal source emits pulse signal according to fixed pulse repetition frequency;In N pulse periods, the signal of each receiving channel is modulated using N*N element orthogonal matrix, the amplitude estimation value and phase estimation value of each receiving channel are obtained by correlating calculation of the conjugate complex code corresponding to each receiving channel and the synthesized signal, and then the amplitude calibration coefficient and phase calibration coefficient are obtained, the calibration of each channel of active array is realized, and the problem that the mutual coupling effect between each channel in the active array of traditional calibration method cannot be reflected in analog beam forming architecture is solved.

Description

Technical Field

[0001] This invention relates to the field of radar detection technology, specifically to an active array multi-channel calibration method and system based on quadrature phase shift modulation. Background Technology

[0002] For multi-channel active arrays, there are active or passive devices such as low-noise amplifiers, phase shifters, and filters in each channel. Due to the influence of manufacturing processes, the electrical parameters of the devices in different channels are not completely consistent. Moreover, during use, the operating characteristics of each device will vary due to the influence of operating voltage, operating time, ambient temperature, and other conditions. In addition, the antenna elements of each channel have mutual coupling and edge effects, which will also lead to amplitude and phase inconsistencies between channels, i.e., channel amplitude and phase mismatch.

[0003] Channel amplitude-phase mismatch can severely impact the performance of active array radar systems. For multi-channel active array radar systems, beamforming relies on the amplitude and phase consistency of the signals in each channel. Differences in amplitude and phase between channels can lead to beam pointing deviation, increased sidelobe levels, or decreased gain. To ensure the normal operation of an active array radar system, calibration of the active array is necessary.

[0004] Currently, for active arrays with analog beamforming architecture, the output of their RF common port is the superposition of signals from each receiving channel. However, the traditional method of individually activating each receiving channel for sampling and calibration cannot reflect the influence of the mutual coupling effect between the channels, making it difficult to achieve accurate calibration of each channel of the active array.

[0005] Therefore, how to calibrate multiple channels of an active array while taking into account the mutual coupling effect between channels is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] To address the shortcomings of existing technologies, this invention provides a method and system for calibrating active arrays based on quadrature phase shift modulation. This solves the technical problem that the traditional method of individually activating each receiving channel for sampling and calibration during the calibration of active arrays with analog beamforming architectures cannot reflect the influence of mutual coupling effects between channels.

[0008] (II) Technical Solution

[0009] To achieve the above objectives, the present invention provides the following technical solution:

[0010] In a first aspect, the present invention provides an active array multi-channel calibration method and system based on quadrature phase shift modulation, comprising the following steps:

[0011] Place the active array in an anechoic chamber or an open outdoor area, and place a calibration signal source at a position directly opposite the active array and at a set distance R perpendicular to the active array.

[0012] The calibration signal source emits pulse signals at a fixed pulse repetition frequency;

[0013] Within N pulse cycles, the signals of each receiving channel are modulated using an N×N unit orthogonal matrix to obtain the modulated signals of each receiving channel, and the composite signal output by the combined signals of each receiving channel is recorded.

[0014] Correlation calculations are performed on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude and phase estimates of each receiving channel.

[0015] By selecting the first receiving channel as the reference channel and comparing the amplitude and phase estimates of each receiving channel, the amplitude calibration coefficient and phase calibration coefficient of the i-th receiving channel relative to the first receiving channel can be obtained.

[0016] The amplitude and phase of each receiving channel can be compensated by using the obtained amplitude and phase calibration coefficients, thus completing the calibration of each receiving channel in the active array.

[0017] Preferably, the active array adopts an analog beamforming architecture. Each receiving channel of the active array includes a receiving antenna. Multiple channel output ports are combined into a common channel output port through a power unit. Each receiving channel of the active array receives signals through the receiving antenna and outputs them through the combined common channel output port.

[0018] Preferably, the active array is a two-dimensional array containing N receiving channels, where N=N x ×N y N x N represents the number of receive channels in the x-direction of the active array. y N represents the number of receive channels in the y-direction of the active array. x ≥1, N y ≥1, and N x and N y They are not both equal to 1.

[0019] Preferably, the active array is placed in an anechoic chamber or an open outdoor area, and a calibration signal source is placed directly opposite the active array at a predetermined distance R perpendicular to it.

[0020] The set distance R between the active array and the calibration signal source needs to meet the following conditions:

[0021]

[0022]

[0023]

[0024] Where R1 is the distance that the active array needs to satisfy in the x-direction, and L... x R0 is the length of the active array in the x-direction, R2 is the distance that the active array needs to satisfy in the y-direction, and L0 is the length of the active array in the x-direction. y Let λ be the length of the active array in the y-direction, and λ be the wavelength corresponding to the center frequency of the active array.

[0025] Preferably, within N pulse periods, an N×N unit orthogonal matrix is ​​used to modulate the signals of each receiving channel, obtain the modulated signals of each receiving channel, and record the composite signal output after synthesis from each receiving channel:

[0026] The modulation of the received signals by each receiving channel is achieved through the phase shifter built into each receiving channel;

[0027] In this N×N unit orthogonal matrix, each element is either 1 or -1, each row of the matrix is ​​mutually orthogonal, each row of the orthogonal matrix corresponds to a receiving channel, and each channel uses one row of the matrix as a coded code group during modulation.

[0028] For the i-th receiving channel, the modulated signal s i (t) can be represented as:

[0029]

[0030] Where 1≤i≤N, For quadrature modulation signals, t is the pulse period number, 1≤t≤N, a i Let φ be the gain of the i-th receiving channel. i Let n be the phase of the i-th receiving channel. i The inherent noise of the i-th receiving channel;

[0031] The composite signal s output after combining the individual channels c (t) can be represented as:

[0032] .

[0033] Preferably, correlation calculations are performed on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude estimate and phase estimate of each receiving channel:

[0034] Among them, the composite signal s cThe correlation calculation between (t) and the conjugate complex digital codes corresponding to the quadrature modulation signals of each receiving channel can be expressed as:

[0035]

[0036] in, It is the conjugate complex digital code corresponding to the quadrature modulation signal of the i-th receiving channel.

[0037] Preferably, when using the obtained amplitude calibration coefficients and phase calibration coefficients to compensate for the amplitude and phase of each receiving channel:

[0038] Wherein, the amplitude calibration coefficient A of the i-th receiving channel relative to the 1st receiving channel mpi and phase calibration coefficient A ci Specifically:

[0039]

[0040]

[0041] The calibrated signal S of the i-th receiving channel bci It can be represented as:

[0042] .

[0043] Secondly, the present invention provides an active array multi-channel calibration system based on quadrature phase shift modulation, the calibration system comprising:

[0044] Signal source positioning module: The active array is placed in an anechoic chamber or an open outdoor area. A calibration signal source is placed at a position directly opposite the active array and at a set distance R perpendicular to the active array.

[0045] Pulse signal transmission module: The calibration signal source transmits pulse signals at a fixed pulse repetition frequency;

[0046] Signal modulation module: Within N pulse cycles, the signal of each receiving channel is modulated using an N×N unit orthogonal matrix to obtain the modulated signal of each receiving channel, and the composite signal output after synthesis from each receiving channel is recorded.

[0047] Signal calculation module: Performs correlation calculations on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude estimate and phase estimate of each receiving channel;

[0048] Estimated value comparison module: Select the first receiving channel as the reference channel, compare the amplitude and phase estimates of each receiving channel, and obtain the amplitude calibration coefficient and phase calibration coefficient of the i-th receiving channel relative to the first receiving channel;

[0049] Channel compensation module: The amplitude and phase of each receiving channel are compensated using the obtained amplitude calibration coefficients and phase calibration coefficients, thereby completing the calibration of each receiving channel in the active array.

[0050] Thirdly, the present invention provides a computer-readable storage medium for an active array multi-channel calibration method and system based on quadrature phase shift modulation, which stores a computer program for calibrating the system, wherein the computer program causes a computer to execute the active array multi-channel calibration method.

[0051] Fourthly, the present invention provides an active array multi-channel calibration method and system electronic device based on quadrature phase shift modulation, comprising:

[0052] One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including methods for performing the active array multichannel calibration method.

[0053] (III) Beneficial Effects

[0054] This invention provides a method and system for multi-channel calibration of active arrays based on quadrature phase shift modulation. Compared with existing technologies, it has the following advantages:

[0055] This invention provides a method and system for multi-channel calibration of active arrays based on orthogonal phase shift modulation. For active arrays with multi-channel analog beamforming architecture, a signal source placed in the far field of the active array antenna transmits pulse signals. Each receiving channel modulates the signal according to a preset orthogonal matrix. By performing correlation calculations between the synthesized signal and the conjugate complex digital code corresponding to each receiving channel, the amplitude estimate and phase estimate of each receiving channel are obtained, thereby obtaining the amplitude calibration coefficient and phase calibration coefficient, and realizing the calibration of each channel of the active array.

[0056] Therefore, it can be seen that the present invention only requires a simple calibration auxiliary device to realize the calibration of multiple channels of active array. The overall calibration method is simple and easy to implement, and it solves the problem that the mutual coupling effect between channels cannot be reflected in the traditional calibration method. Attached Figure Description

[0057] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 A flowchart illustrating an active array multi-channel calibration method and system based on quadrature phase shift modulation provided by the present invention.

[0059] Figure 2 This is a schematic diagram of an active array multi-channel calibration scenario provided by the present invention;

[0060] Figure 3 This invention provides a typical 8×8 element orthogonal matrix.

[0061] Figure 4 This invention provides a schematic diagram of an 8-channel active array quadrature phase shift modulation.

[0062] Figure 5 The signal waveforms of the eight receiving channels provided by this invention before modulation;

[0063] Figure 6 The modulation signal waveforms of the eight receiving channels provided by this invention;

[0064] Figure 7 The signal waveforms after quadrature modulation of the eight receiving channels provided by this invention;

[0065] Figure 8 The composite signal waveform output after combining the eight receiving channels provided by this invention;

[0066] Figure 9 The signal waveforms of the eight receiving channels provided by this invention are compensated by amplitude calibration coefficients and phase calibration coefficients. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] This application provides a method and system for calibrating active arrays based on quadrature phase shift modulation. This solves the problem that the traditional method of individually activating each receiving channel for sampling and calibration cannot reflect the mutual coupling effect between channels when calibrating active arrays with analog beamforming architectures. This method achieves accurate calibration of each channel of the active array.

[0069] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0070] The following is a detailed explanation of each step:

[0071] This invention provides a method and system for calibrating an active array multichannel based on quadrature phase shift modulation, comprising the following steps:

[0072] S1: Place the active array in an anechoic chamber or an open outdoor area. Place a calibration signal source directly opposite the active array at a predetermined distance R perpendicular to it. The active array is a two-dimensional array containing N receiving channels, where N = N0 x ×N y N x N represents the number of receive channels in the active array along the x-direction. y N represents the number of receive channels in the y-direction of the active array. x ≥1, N y ≥1, and N x and N y They are not both equal to 1.

[0073] It should be noted that the active array adopts an analog beamforming architecture. The received signals from each receiving channel of the active array are combined and output through a common port. Moreover, each receiving channel of the active array contains a receiving antenna and a phase shifter.

[0074] In an active array employing an analog beamforming architecture, multiple channels are directly combined into a single channel via a power combiner. Therefore, during normal operation, only the combined signal from multiple channels can be obtained, and it is impossible to obtain the signal of a single channel alone. Alternatively, when the signal of a single channel is obtained by shutting down other channels, the other channels are also shut down, and the obtained signal cannot take into account the influence of the mutual coupling between other channels. In this case, it is not in a normal operating state.

[0075] In addition, the set distance R between the active array and the calibration signal source needs to meet the following conditions:

[0076]

[0077]

[0078]

[0079] Where R1 is the distance that the active array needs to satisfy in the x-direction, and L... x R0 is the length of the active array in the x-direction, R2 is the distance that the active array needs to satisfy in the y-direction, and L0 is the length of the active array in the x-direction. y Let λ be the length of the active array in the y-direction, and λ be the wavelength corresponding to the center frequency of the active array.

[0080] like Figure 2As shown, the active array is placed in an anechoic chamber or an open outdoor area. A signal generator and a horn antenna are placed directly opposite the active array and at a set distance R perpendicular to the active array as a calibration signal source.

[0081] The required R value is calculated based on the frequency and length of the active array. For example, for a common S-band (e.g., a center frequency of 2.4 GHz, corresponding to a wavelength of 0.125 meters), the length L of the active array in the x-direction is... x The length L of the active array in the y-direction is 0.25 meters. y The distance R1 required for the active array in the x direction is 1 meter, and the distance R2 required for the active array in the y direction is 0.25 meters. Therefore, the set distance R between the active array and the calibration signal source should be at least 1 meter.

[0082] S2: The calibration signal source emits pulse signals at a fixed pulse repetition frequency.

[0083] It should be noted that the calibration signal source used can transmit the pulse signal required by the active array at a certain repetition frequency;

[0084] S3: Within N pulse periods, an N×N unit orthogonal matrix is ​​used to modulate the signals of each receiving channel, and the composite signal s output after combining the signals from each receiving channel is obtained. c (t) is used for recording.

[0085] It should be noted that each element of an N×N orthogonal matrix is ​​either 1 or -1, and each row of the matrix is ​​mutually orthogonal. Each row of the orthogonal matrix corresponds to a receiving channel, and during modulation, each channel uses one row of the matrix as the coded code group. For example: Figure 3 The image shows an 8×8 element Walsh-Hadamard matrix, which is a typical orthogonal matrix.

[0086] Example:

[0087] For an 8-channel active array, orthogonal modulation is performed using an 8×8 unit Walsh-Hadamard matrix, such as... Figure 4 As shown. The quadrature modulation signal is Where i is the index of the receiving channel, 1≤i≤N, t is the index of the pulse period, 1≤t≤N, and m is the element value of the i-th receiving channel in the orthogonal matrix corresponding to the t-th pulse. When m=1, the phase of the orthogonal modulation signal is 90°, and when m=-1, the phase of the orthogonal modulation signal is -90°. The modulation of the received signal of each receiving channel can be achieved by the phase shifter built into each receiving channel. It can be seen that the orthogonal modulation signal only changes the phase of the receiving channel signal, while keeping the amplitude of the receiving channel signal unchanged. For the i-th receiving channel, the modulated signal s i (t) can be represented as:

[0088]

[0089] Among them, a i Let φ be the gain of the i-th receiving channel. i Let n be the phase of the i-th receiving channel. i Let be the inherent noise of the i-th receiving channel.

[0090] The composite signal s output after combining the individual channels c (t) can be represented as:

[0091]

[0092] S4: For composite signal s c (t) Correlation calculations are performed with the conjugate complex digital codes corresponding to the quadrature modulation signals of each receiving channel to obtain the amplitude estimates of each receiving channel. and phase estimate .

[0093] It should be noted that the composite signal s c The correlation calculation between (t) and the conjugate complex digital codes corresponding to the quadrature modulation signals of each receiving channel can be expressed as:

[0094]

[0095] in, It is the conjugate complex digital code corresponding to the quadrature modulation signal of the i-th receiving channel.

[0096] S5: Select the first receiving channel as the reference channel, compare the amplitude and phase estimates of each receiving channel, and obtain the amplitude calibration coefficient A of the i-th receiving channel relative to the first receiving channel. mpi and phase calibration coefficient A ci Specifically:

[0097]

[0098]

[0099] in, This is the amplitude estimate for the first receiving channel. This is the phase estimate for the first receiving channel.

[0100] S6: Use the obtained amplitude calibration coefficient A mpi and phase calibration coefficient A ci By compensating for the amplitude and phase of each receiving channel, the calibration of each receiving channel in the active array can be completed.

[0101] It should be noted that: the signal S after calibration of the i-th receiving channel bci It can be represented as:

[0102]

[0103] Example:

[0104] Figures 5-9 The paper presents a comparison of the effects of the proposed method and system for multi-channel calibration of active arrays based on quadrature phase shift modulation on the active array before and after calibration.

[0105] In this scenario, the active array has a total of 8 receiving channels;

[0106] in, Figure 5 The signal waveforms of the eight receiving channels of the active array before modulation are given. It can be seen that there is inconsistency in the signal amplitude and phase between the channels.

[0107] Figure 6 The quadrature modulation signal is given, and Figure 3 The elements of the 8×8 element orthogonal matrix shown correspond to each other;

[0108] Figure 7 The signal waveforms after quadrature modulation of the 8 receiving channels of the active array are given;

[0109] Figure 8 The waveform of the composite signal output after combining the eight receiving channels of the active array is given;

[0110] Figure 9 The signal waveforms of the eight receiving channels of the active array after compensation with amplitude and phase calibration coefficients are given. It can be seen that after the calibration method is performed, the signal amplitude and phase of each channel are basically consistent, which significantly improves the amplitude and phase consistency of each channel of the active array.

[0111] In summary, compared with existing technologies, it has the following beneficial effects:

[0112] This invention provides a method and system for multi-channel calibration of active arrays based on orthogonal phase shift modulation. For active arrays with multi-channel analog beamforming architecture, a signal source placed in the far field of the active array antenna transmits pulse signals. Each receiving channel modulates the signal according to a preset orthogonal matrix. By performing correlation calculations between the synthesized signal and the conjugate complex digital code corresponding to each receiving channel, the amplitude estimate and phase estimate of each receiving channel are obtained, thereby obtaining the amplitude calibration coefficient and phase calibration coefficient, and realizing the calibration of each channel of the active array.

[0113] Therefore, it can be seen that the present invention only requires a simple calibration auxiliary device to realize the calibration of multiple channels of active array. The overall calibration method is simple and easy to implement, and it solves the problem that the mutual coupling effect between channels cannot be reflected in the traditional calibration method.

[0114] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0115] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for calibrating a multi-channel active array based on quadrature phase shift modulation, characterized in that, Includes the following steps: Place the active array in an anechoic chamber or an open outdoor area, and place a calibration signal source at a position directly opposite the active array and at a set vertical distance from the active array. The calibration signal source emits pulse signals at a fixed pulse repetition frequency; Within N pulse cycles, the signals of each receiving channel are modulated using an N×N unit orthogonal matrix to obtain the modulated signals of each receiving channel, and the composite signal output by the combined signals of each receiving channel is recorded. In this N×N unit orthogonal matrix, each element is either 1 or -1, each row of the matrix is ​​mutually orthogonal, each row of the orthogonal matrix corresponds to a receiving channel, and each channel uses one row of the matrix as a coded code group during modulation. For an 8-channel active array, orthogonal modulation is performed using an 8×8 element Walsh-Hadamard matrix. The orthogonal modulation signal is... ; Where i is the sequence number of the receiving channel, 1≤i≤N, t is the sequence number of the pulse period, 1≤t≤N, and m is the element value of the i-th receiving channel in the t-th pulse in the orthogonal matrix. When m=1, the phase of the orthogonal modulation signal is 90°, and when m=-1, the phase of the orthogonal modulation signal is -90°. The modulation of the received signal of each receiving channel is achieved by the phase shifter built into each receiving channel. Correlation calculations are performed on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude and phase estimates of each receiving channel. By selecting the first receiving channel as the reference channel and comparing the amplitude and phase estimates of each receiving channel, the amplitude calibration coefficient and phase calibration coefficient of the i-th receiving channel relative to the first receiving channel can be obtained. The amplitude and phase of each receiving channel can be compensated by using the obtained amplitude and phase calibration coefficients, thus completing the calibration of each receiving channel in the active array.

2. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 1, characterized in that, The active array adopts an analog beamforming architecture. Each receiving channel of the active array contains a receiving antenna. Multiple channel output ports are combined into a common channel output port through a power unit. Each receiving channel of the active array receives signals through the receiving antenna and outputs them through the combined common channel output port.

3. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 1, characterized in that, The active array is a two-dimensional array containing N receiving channels, where N=N x ×N y N x N represents the number of receive channels in the active array along the x-direction. y N represents the number of receive channels in the y-direction of the active array. x ≥1, N y ≥1, and N x and N y They are not both equal to 1.

4. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 1, characterized in that, Place the active array in an anechoic chamber or an open outdoor area, and place a calibration signal source at a predetermined distance directly opposite the active array and perpendicular to it. The set distance R between the active array and the calibration signal source needs to meet the following conditions: Where R1 is the distance that the active array needs to satisfy in the x-direction, and L... x R0 is the length of the active array in the x-direction, R2 is the distance that the active array needs to satisfy in the y-direction, and L0 is the length of the active array in the x-direction. y Let λ be the length of the active array in the y-direction, and λ be the wavelength corresponding to the center frequency of the active array.

5. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 1, characterized in that, Within N pulse periods, an N×N unit orthogonal matrix is ​​used to modulate the signals of each receiving channel, acquire the modulated signals of each receiving channel, and record the composite signal output from the combined signals of each receiving channel: The modulation of the received signals by each receiving channel is achieved through the phase shifter built into each receiving channel; In this N×N unit orthogonal matrix, each element is either 1 or -1, each row of the matrix is ​​mutually orthogonal, each row of the orthogonal matrix corresponds to a receiving channel, and each channel uses one row of the matrix as a coded code group during modulation. For the i-th receiving channel, the modulated signal s i (t) can be represented as: Where 1≤i≤N, For quadrature modulation signals, t is the pulse period number, 1≤t≤N, a i Let φ be the gain of the i-th receiving channel. i Let n be the phase of the i-th receiving channel. i The inherent noise of the i-th receiving channel; The composite signal s output after combining the individual channels c (t) can be represented as: 。 6. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 5, characterized in that, Correlation calculations are performed on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude and phase estimates for each receiving channel: Among them, the composite signal s c The correlation calculation between (t) and the conjugate complex digital codes corresponding to the quadrature modulation signals of each receiving channel can be expressed as: in, It is the conjugate complex digital code corresponding to the quadrature modulation signal of the i-th receiving channel; This is an estimate of the magnitude. This is the phase estimate.

7. The active array multi-channel calibration method based on quadrature phase shift modulation as described in claim 6, characterized in that, When using the obtained amplitude calibration coefficients and phase calibration coefficients to compensate for the amplitude and phase of each receiving channel: Wherein, the amplitude calibration coefficient A of the i-th receiving channel relative to the 1st receiving channel mpi and phase calibration coefficient A ci Specifically: The calibrated signal S of the i-th receiving channel bci It can be represented as: 。 8. An active array multi-channel calibration system based on quadrature phase shift modulation, characterized in that, The calibration system includes: Signal source positioning module: The active array is placed in an anechoic chamber or an open outdoor area. A calibration signal source is placed at a position directly opposite the active array and at a set distance R perpendicular to the active array. Pulse signal transmission module: The calibration signal source transmits pulse signals at a fixed pulse repetition frequency; Signal modulation module: Within N pulse cycles, the signal of each receiving channel is modulated using an N×N unit orthogonal matrix to obtain the modulated signal of each receiving channel, and the composite signal output after synthesis from each receiving channel is recorded. In this N×N unit orthogonal matrix, each element is either 1 or -1, each row of the matrix is ​​mutually orthogonal, each row of the orthogonal matrix corresponds to a receiving channel, and each channel uses one row of the matrix as a coded code group during modulation. For an 8-channel active array, orthogonal modulation is performed using an 8×8 element Walsh-Hadamard matrix. The orthogonal modulation signal is... ; Where i is the sequence number of the receiving channel, 1≤i≤N, t is the sequence number of the pulse period, 1≤t≤N, and m is the element value of the i-th receiving channel in the t-th pulse in the orthogonal matrix. When m=1, the phase of the orthogonal modulation signal is 90°, and when m=-1, the phase of the orthogonal modulation signal is -90°. The modulation of the received signal of each receiving channel is achieved by the phase shifter built into each receiving channel. Signal calculation module: Performs correlation calculations on the conjugate complex digital signals corresponding to the composite signal and the quadrature modulation signals of each receiving channel to obtain the amplitude estimate and phase estimate of each receiving channel; Estimated value comparison module: Select the first receiving channel as the reference channel, compare the amplitude and phase estimates of each receiving channel, and obtain the amplitude calibration coefficient and phase calibration coefficient of the i-th receiving channel relative to the first receiving channel; Channel compensation module: The amplitude and phase of each receiving channel are compensated using the obtained amplitude calibration coefficients and phase calibration coefficients, thereby completing the calibration of each receiving channel in the active array.

9. A computer-readable storage medium for an active array multi-channel calibration method based on quadrature phase shift modulation, characterized in that, It stores a computer program for calibrating the system, wherein the computer program causes the computer to perform the active array multichannel calibration method as described in any one of claims 1 to 7.

10. An electronic device based on an active array multi-channel calibration method using quadrature phase shift modulation, characterized in that, include: One or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the programs including methods for performing an active array multichannel calibration method as described in any one of claims 1 to 7.

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