Darkroom calibration and verification method, device and system for curved surface phased array antenna

Abstract

The invention discloses a darkroom calibration and verification method, device and system for a curved surface phased array antenna, and belongs to the field of antennae, and the method comprises the steps: building a darkroom calibration environment; the phased-array antenna can be rotated through a built darkroom calibration environment, so that the azimuth can be changed from 0 to 360 degrees, and the pitching can be changed from 0 to 90 degrees; the rotation time and angle and the calibration instruction issuing time of the debugging computer are adjusted, so that the rotation time and angle and the calibration instruction issuing time of the debugging computer are mutually cooperated to traverse all azimuth pitching calibration processes, and a calibration result is issued to the storage module, so that the full-link automatic calibration of the curved surface array can be realized in combination with the mechanical arm; the method not only can obtain the phase and amplitude of each channel required by beam forming, but also can detect antenna internal hardware such as an array element, a radio frequency front end, a channel, an AD channel and the like and calculate performance indexes so as to verify a calibration result, and has the advantages of high efficiency, safety and rapidness.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically, to a method, apparatus, and system for anechoic chamber calibration and verification of curved phased array antennas. Background Technology

[0002] The key to beamforming of a phased array antenna is the consistency of amplitude and phase characteristics of the antenna element channels. Inconsistency in amplitude and phase has a significant impact on technical indicators such as beam pointing and sidelobe level, and in severe cases, it may even prevent beamforming. Due to factors such as the machining precision of components, the installation of various components, connectors, and connecting cables, the amplitude and phase characteristics of each channel are also inconsistent. Therefore, it is necessary to calibrate the amplitude and phase consistency of the antenna element channels. The amplitude and phase data obtained from the calibration can be used to calculate weights, which are used to compensate the corresponding channels in the digital domain during beamforming. This is one of the differences from the calibration of traditional parabolic antenna telemetry and control stations.

[0003] An existing solution, a phased array antenna amplitude and phase calibration method (publication number CN119199289A), relies on test data from two test systems. Each test system involves steps such as anechoic chamber installation and environmental setup, and requires manual operation of a ground-based testing computer to acquire amplitude and phase data at different waveforms and frequencies for each receiving channel. The setup of two test systems and the need to operate the ground-based testing computer to acquire amplitude and phase data at different waveforms and frequencies for each receiving channel result in long testing cycles, low efficiency, high testing costs, and the inability to detect antenna hardware status, hindering troubleshooting.

[0004] An existing solution, a rapid automatic calibration method for the angle measurement coefficients of a phased array radar (publication number CN118962606A), obtains the effective values ​​of the azimuth and elevation angle measurement coefficients of the phased array radar system under different operating frequencies and waveforms by traversing all frequency points and all operating waveforms. However, this solution requires repeated manual loading of target information parameters and switching the radar system on and off during the traversal of all frequency points and waveforms. The process is cumbersome, requiring continuous manual switching to complete the traversal of frequency points and waveforms, resulting in a long testing cycle. Furthermore, it cannot detect the internal hardware status of the antenna, making troubleshooting difficult. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method, device and system for anechoic chamber calibration and verification of curved phased array antennas. It can not only obtain the phase and amplitude of each channel required for beamforming, but also detect the internal hardware of the antenna such as array elements, radio frequency front-end, channel, and AD channel, and calculate the performance indicators, thereby verifying the calibration results. It has the advantages of high efficiency, safety and speed.

[0006] The objective of this invention is achieved through the following solution: A method for anechoic chamber calibration and verification of a curved phased array antenna, comprising the following steps: S1, Set up a darkroom calibration environment; S2, after installation, can rotate the phased array antenna through the built anechoic chamber calibration environment to achieve azimuth changes from 0 to 360° and elevation changes from 0 to 90°; by adjusting the rotation time, angle and the time of calibration command issued by the debugging computer, the two can work together to traverse the calibration process of all azimuth and elevation. After the calibration process is completed, the calibration results are sent to the flash storage module. S3, execute the calibration process; S4. After calibration, the calibration results are verified by calculating performance indicators, including aperture level and G / T value. After the debugging software issues the beamforming command, the ZYNQ software verifies the beamforming results according to formula (1) based on the channel amplitude. Channel phase The weights are obtained to compensate for system inconsistencies. The frequency control word is calculated based on the frequency point and clock frequency according to equation (2). The relevant parameters are then sent to the FPGA software. (1); (2); Where i represents the channel number. Indicates the desired output frequency. Indicates the working clock, This represents the ratio of antenna gain G to system noise temperature T. The FPGA software weights the AD data using a complex multiplier based on the weights, then accumulates the data, and finally performs orthogonal downconversion and filtering on the accumulated result to complete beamforming. After beamforming, the carrier-to-noise ratio is measured by connecting a spectrum analyzer through the intermediate frequency signal observation port. The effective isotropic radiated power is calculated using equation (3). The outlet level is calculated using equation (4). Calculated using equation (5) The value is used to verify whether the calibration results are correct. (3); +20 (4); (5).

[0007] Furthermore, in step S1, the establishment of the darkroom calibration environment specifically includes the following sub-steps: Two robotic arms are installed in an anechoic chamber, and their positions are calibrated. The two arms are independently controlled and automatically rotate according to time and angle settings. The first robotic arm is equipped with a horn antenna, which is connected to a signal source outside the anechoic chamber via an RF cable. The horn antenna's normal is aligned with the phased array antenna under test, and it transmits a single-carrier signal. The RF cable loss is [missing information]. The gain of the horn antenna is The frequency of the single-carrier signal transmitted by the signal source is The transmission power is A phased array antenna is mounted on the second robotic arm, and the phased array antenna and the horn antenna are aligned in their normal directions, with a spatial distance of [missing information]. The intermediate frequency signal observation port and network port of the phased array antenna are connected to the spectrum analyzer and debugging computer outside the anechoic chamber, respectively. The debugging computer is equipped with debugging software.

[0008] Furthermore, in step S2, the phased array antenna can be rotated in the constructed anechoic chamber calibration environment to achieve azimuth changes from 0 to 360° and elevation changes from 0 to 90°; this is achieved by adjusting the rotation time, angle, and the timing of calibration commands issued by the calibration computer, specifically including: The second robotic arm rotates the phased array antenna to achieve azimuth changes from 0 to 360°, and the second robotic arm itself can rotate to achieve pitch changes from 0 to 90°. The timing and angle of the second robotic arm's rotation are adjusted, as well as the timing of calibration commands issued by the computer.

[0009] Furthermore, in step S2, the storage module includes a storage flash.

[0010] Furthermore, in step S3, the calibration process specifically includes the following sub-steps: S31: After the debugging software issues calibration commands according to the azimuth and elevation traversal, the ZYNQ software sets and issues calibration-related parameters for each channel, with the frequency control word being a fixed value. S32: After receiving the relevant calibration parameters, the FPGA software weights the real and imaginary AD data in the digital domain using a complex multiplier, then accumulates them, and then downconverts and filters the accumulated results to form reference beam data and calibration beam data. S33: Perform phase and amplitude calibration calculations; S34: After receiving the data calculated by the FPGA calibration, the ZYNQ software performs an arctangent operation on the phase to convert it into degrees, thus obtaining the calibrated phase; it then performs a square root operation on the ratio of the amplitudes; and finally sends the calibration result to the debugging software. S35: After confirming the calibration results, the debugging software sends out the calibration results, and the ZYNQ software writes the calibration results to the storage flash. S36: Turn off the signal source. If the reference channel number issued by the debugging software is modified to a selected channel number, that is, the reference channel phase is a DC signal, the antenna transmits the corresponding frequency signal through the internal channel, which is coupled to the AD channel through the antenna subarray. Repeat the process of steps S32-S34 to detect whether the internal phase of each channel of the antenna has changed and to verify whether the internal hardware state of the antenna has changed.

[0011] Furthermore, in step S31, the calibration-related parameters specifically include: reference channel number, calibration channel number, frequency control word, reference beam reference channel weight, and calibration beam channel weight.

[0012] Furthermore, in step S33, the phase calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data, and low-pass filtering and comb filtering are combined to achieve selective enhancement and noise suppression of the frequency band signal; second, conjugate operation is performed; and finally, time-domain integration and periodic reset are performed again.

[0013] Furthermore, in step S33, the amplitude calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data; then, the real and imaginary parts of the reference and calibration beams are respectively subjected to sum of squares; and finally, time-domain integration and periodic reset are performed again.

[0014] An anechoic chamber calibration and verification device for a curved phased array antenna includes a processor and a memory, wherein the memory stores a computer program that, when loaded by the processor, executes the method described in any of the preceding methods.

[0015] An anechoic chamber calibration and verification system for a curved phased array antenna includes the anechoic chamber calibration and verification device for the curved phased array antenna as described above.

[0016] The beneficial effects of this invention include: (1) This invention constructs a new anechoic chamber calibration environment: it involves setting up two robotic arms in the anechoic chamber, one for installing a horn antenna and the other for installing a phased array antenna. The robotic arms can be independently controlled and rotated automatically, adjusting the rotation time and angle of the robotic arm 2 and the time when the calibration command is issued by the debugging computer, thereby covering all azimuth and elevation angles; (2) This invention realizes the concept of automating the calibration process: by relying on the cooperation between the robotic arm and the calibration process, each orientation and pitch can be automatically traversed, which is simple to operate, saves calibration time, simplifies the calibration process, and is efficient and safe; (3) The implementation concept of the calibration method of the present invention: the phase and amplitude are calculated by the reference beam and the calibration beam, and the weight is calculated by the phase and amplitude. The inconsistency of the system is compensated by the weight. If the reference beam is taken as a DC signal, the calibration can check whether the phase of each channel has changed, which can verify whether the internal hardware state of the antenna has changed, and facilitate troubleshooting. (4) Implementation concept of the calibration architecture of this invention: In the calibration process, ZYNQ software and FPGA software work together. ZYNQ software is responsible for configuring and issuing calibration parameters, while FPGA software is responsible for processing AD data and performing phase and amplitude calibration calculations. A new coordinated workflow is proposed to achieve the effect of fast processing speed; (5) The calibration method of the present invention enhances the signal-to-noise ratio through time-domain integration and periodic reset, resulting in high accuracy and strong stability. The correctness of the calibration results can be verified by calculating the antenna performance indicators. Attached Figure Description

[0017] 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.

[0018] Figure 1 Schematic diagram of the darkroom calibration environment; Figure 2 A flowchart of the calibration process; Figure 3 This is a flowchart of beamforming. 1- Horn antenna, 2- First robotic arm, 3- Phased array antenna of the surface under test, 4- Second robotic arm. Detailed Implementation

[0019] All features disclosed in all embodiments of this specification, or steps in all methods or processes implied in the disclosure, may be combined and / or extended or replaced in any way, except for mutually exclusive features and / or steps.

[0020] This invention discloses an automatic anechoic chamber calibration and verification method for curved phased array antennas. The aim is to provide an automatic anechoic chamber calibration method for phased array antennas, which not only obtains the phase and values ​​of each channel required for beamforming, but also tests the internal hardware of the antenna and calculates performance indicators, thereby verifying the calibration results. More specifically, it includes the following steps: Step S1: Set up the darkroom calibration environment.

[0021] a) In the dark room, the two robotic arms follow the... Figure 1 The robotic arms are installed and their positions are calibrated. The two robotic arms can be controlled independently and can be set to rotate automatically according to time and angle. b): A horn antenna 1 is mounted on the first robotic arm 2. The horn antenna 1 is connected to a signal source outside the anechoic chamber via an RF cable. The normal of the horn antenna 1 is aligned with the phased array antenna 3 of the surface under test, and it transmits a single-carrier signal. The RF cable loss is... The gain of the horn antenna is The frequency of the single-carrier signal transmitted by the signal source is The transmission power is ; c): The phased array antenna 3 for the surface to be tested is mounted on the second robotic arm 4. The phased array antenna and the horn antenna are aligned in their normal directions, with a spatial distance of [missing information]. The intermediate frequency signal observation port and network port of the phased array antenna are connected to the spectrum analyzer and debugging computer outside the anechoic chamber, respectively. The debugging computer is equipped with debugging software.

[0022] Step S2, according to... Figure 1 After installation, the azimuth of the phased array antenna can be changed from 0 to 360° by rotating the second robotic arm 4, and the pitch can be changed from 0 to 90° by rotating the second robotic arm 4 itself. By adjusting the rotation time and angle of the second robotic arm 4 and the time of the calibration command issued by the debugging computer, the two can work together to traverse the calibration process of all azimuth and pitch. After the calibration process is completed, the calibration results are sent to the flash memory module.

[0023] Step S3, calibration process, as follows Figure 2 .

[0024] a) After the debugging software automatically traverses and issues calibration commands according to azimuth and elevation, the ZYNQ software sets and issues calibration-related parameters for each channel (reference channel number, calibration channel number, frequency control word, reference beam reference channel weight, calibration beam channel weights, etc.), and the frequency control word is a fixed value; b): After receiving the relevant calibration parameters, the FPGA software weights the real and imaginary AD data in the digital domain using a complex multiplier, then accumulates them, and then downconverts and filters the accumulated results to form reference beam data and calibration beam data. c): Subsequently, phase and amplitude calibration calculations are performed. In the phase calibration calculation, the reference and calibration beam data are first integrated in the time domain and periodically reset. Low-pass filtering and comb filtering are combined to achieve selective enhancement and noise suppression of signals in specific frequency bands. Then, conjugate operation is performed, and finally, time domain integration and periodic reset are performed again. In the amplitude calibration calculation, the reference and calibration beam data are first integrated in the time domain and periodically reset. Then, the real and imaginary parts of the reference and calibration beams are squared and summed, and finally, time domain integration and periodic reset are performed again. d): After receiving the data from the FPGA calibration calculation, the ZYNQ software performs an arctangent operation on the phase to convert it into degrees, thus obtaining the calibrated phase; it then performs a square root operation on the amplitude ratio. The calibration results are then sent to the debugging software. e): After confirming the calibration results, the debugging software sends out the calibration results, and the ZYNQ software writes the calibration results to the flash.

[0025] f): Turn off the signal source. If the reference channel number issued by the debugging software is modified to a specific channel number, that is, the reference channel phase is a DC signal, the antenna transmits the corresponding frequency signal through the internal channel, which is coupled to the AD channel through the antenna subarray. Repeat the bd process to detect whether the internal phase of each channel of the antenna has changed, and to verify whether the internal hardware state of the antenna has changed, which is convenient for troubleshooting.

[0026] Step S4: After calibration, the calibration results can be verified by calculating performance indicators such as port level and G / T value. Figure 3 As shown, after the debugging software issues the beamforming command, the ZYNQ software uses the amplitude according to equation (1). Phase The weights are obtained to compensate for system inconsistencies. The frequency control word is calculated based on the frequency point and clock frequency according to equation (2). The relevant parameters are then sent to the FPGA software. (1); (2); The FPGA software weights the AD data using a complex multiplier based on the weights, then accumulates the data, and finally performs orthogonal downconversion and filtering on the accumulated result to complete beamforming. After beamforming, the carrier-to-noise ratio can be measured by connecting the beamformer to the intermediate frequency signal observation port. The effective isotropic radiation power can be calculated using equation (3). The outlet level is calculated using equation (4). Calculated using equation (5) The value can be used to verify whether the calibration result is correct.

[0027] (3); +20 (4); (5); In summary, the present invention has the following advantages: (1) In the present invention, two robotic arms are used to install a phased array antenna and a passive horn antenna in an anechoic chamber. The rotation delay and angle are set, and the robotic arms rotate automatically to realize the automatic control of the azimuth and elevation of the phased array antenna. Combined with the robotic arms, the entire link of the curved phased array is automatically calibrated. (2) In the present invention, the calibration algorithm calculates the phase and amplitude through the reference beam and the calibration beam, calculates the weights from the phase and amplitudes, and compensates for the inconsistency of the system through the weights; if the reference beam is taken as a DC signal, the calibration can check whether the phase inside each channel changes, and verify whether the internal hardware state of the antenna has changed, which is convenient for troubleshooting. (3) In the present invention, the phased array antenna is implemented based on FPGA+ZYNQ architecture. It is connected to the debugging computer via network cable. The software sets the automatic calibration delay, which is consistent with the rotation delay of the robotic arm. The robotic arm and the phased array antenna work together to complete the calibration process of all azimuth elevations. After that, the calibration results are written into the flash memory module. (4) In the present invention, the weights are calculated by calling the calibration file, beamforming is performed, the intermediate frequency signal observation port of the phased array is connected to the spectrum analyzer to observe the carrier-to-noise ratio, and the performance indicators such as port level and G / T value are calculated to verify the correctness of the calibration results.

[0028] It should be noted that, within the scope of protection defined in the claims of this invention, the following embodiments can be combined and / or extended or replaced in any logical manner from the above specific embodiments, such as the disclosed technical principles, disclosed technical features or implicitly disclosed technical features.

[0029] Example 1 A method for anechoic chamber calibration and verification of a curved phased array antenna, comprising the following steps: S1, Set up a darkroom calibration environment; S2, after installation, can rotate the phased array antenna through the built anechoic chamber calibration environment to achieve azimuth changes from 0 to 360° and elevation changes from 0 to 90°; by adjusting the rotation time, angle and the time of calibration command issued by the debugging computer, the two can work together to traverse the calibration process of all azimuth and elevation. After the calibration process is completed, the calibration results are sent to the flash storage module. S3, execute the calibration process; S4. After calibration, the calibration results are verified by calculating performance indicators, including aperture level and G / T value. After the debugging software issues the beamforming command, the ZYNQ software verifies the beamforming results according to formula (1) based on the channel amplitude. Channel phase The weights are obtained to compensate for system inconsistencies. The frequency control word is calculated based on the frequency point and clock frequency according to equation (2). The relevant parameters are then sent to the FPGA software. (1); (2); Where i represents the channel number. Indicates the desired output frequency. Indicates the working clock, This represents the ratio of antenna gain G to system noise temperature T. The FPGA software weights the AD data using a complex multiplier based on the weights, then accumulates the data, and finally performs orthogonal downconversion and filtering on the accumulated result to complete beamforming. After beamforming, the carrier-to-noise ratio is measured by connecting a spectrum analyzer through the intermediate frequency signal observation port. The effective isotropic radiated power is calculated using equation (3). The outlet level is calculated using equation (4). Calculated using equation (5) The value is used to verify whether the calibration results are correct. (3); +20 (4); (5).

[0030] Example 2 Based on Example 1, step S1, which involves setting up the darkroom calibration environment, specifically includes the following sub-steps: Two robotic arms are installed in an anechoic chamber, and their positions are calibrated. The two arms are independently controlled and automatically rotate according to time and angle settings. The first robotic arm is equipped with a horn antenna, which is connected to a signal source outside the anechoic chamber via an RF cable. The horn antenna's normal is aligned with the phased array antenna under test, and it transmits a single-carrier signal. The RF cable loss is [missing information]. The gain of the horn antenna is The frequency of the single-carrier signal transmitted by the signal source is The transmission power is A phased array antenna is mounted on the second robotic arm, and the phased array antenna and the horn antenna are aligned in their normal directions, with a spatial distance of [missing information]. The intermediate frequency signal observation port and network port of the phased array antenna are connected to the spectrum analyzer and debugging computer outside the anechoic chamber, respectively. The debugging computer is equipped with debugging software.

[0031] Example 3 Based on Example 2, in step S2, the phased array antenna can be rotated through the constructed anechoic chamber calibration environment, achieving azimuth changes from 0 to 360° and elevation changes from 0 to 90°; this is achieved by adjusting the rotation time, angle, and the timing of calibration commands issued by the computer, specifically including: The second robotic arm rotates the phased array antenna to achieve azimuth changes from 0 to 360°, and the second robotic arm itself can rotate to achieve pitch changes from 0 to 90°. The timing and angle of the second robotic arm's rotation are adjusted, as well as the timing of calibration commands issued by the computer.

[0032] Example 4 Based on Embodiment 1, in step S2, the storage module includes a storage flash.

[0033] Example 5 Based on Example 1, step S3, which involves executing the calibration process, specifically includes the following sub-steps: S31: After the debugging software issues calibration commands according to the azimuth and elevation traversal, the ZYNQ software sets and issues calibration-related parameters for each channel, with the frequency control word being a fixed value. S32: After receiving the relevant calibration parameters, the FPGA software weights the real and imaginary AD data in the digital domain using a complex multiplier, then accumulates them, and then downconverts and filters the accumulated results to form reference beam data and calibration beam data. S33: Perform phase and amplitude calibration calculations; S34: After receiving the data calculated by the FPGA calibration, the ZYNQ software performs an arctangent operation on the phase to convert it into degrees, thus obtaining the calibrated phase; it then performs a square root operation on the ratio of the amplitudes; and finally sends the calibration result to the debugging software. S35: After confirming the calibration results, the debugging software sends out the calibration results, and the ZYNQ software writes the calibration results to the storage flash. S36: Turn off the signal source. If the reference channel number issued by the debugging software is modified to a selected channel number, that is, the reference channel phase is a DC signal, the antenna transmits the corresponding frequency signal through the internal channel, which is coupled to the AD channel through the antenna subarray. Repeat the process of steps S32-S34 to detect whether the internal phase of each channel of the antenna has changed and to verify whether the internal hardware state of the antenna has changed.

[0034] Example 6 Based on Example 5, in step S31, the calibration-related parameters specifically include: reference channel number, calibration channel number, frequency control word, reference beam reference channel weight, and calibration beam channel weight.

[0035] Example 7 Based on Example 5, in step S33, the phase calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data, and low-pass filtering and comb filtering are combined to achieve selective enhancement and noise suppression of the frequency band signal; second, conjugate operation is performed; and finally, time-domain integration and periodic reset are performed again.

[0036] Example 8 Based on Example 5, in step S33, the amplitude calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data; then, the real and imaginary parts of the reference and calibration beams are respectively subjected to the sum of squares operation; and finally, time-domain integration and periodic reset are performed again.

[0037] Example 9 An anechoic chamber calibration and verification device for a curved phased array antenna includes a processor and a memory. The memory stores a computer program, which, when loaded by the processor, executes the method described in any one of Embodiments 1 to 8.

[0038] Example 10 An anechoic chamber calibration and verification system for a curved phased array antenna includes the anechoic chamber calibration and verification device for the curved phased array antenna described in Example 9.

[0039] The units described in the embodiments of the present invention can be implemented in software or hardware, and the described units can also be located in a processor. The names of these units do not necessarily limit the specific unit itself.

[0040] According to one aspect of the present invention, a computer program product or computer program is provided, the computer program product or computer program including computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium, and executes the computer instructions, causing the computer device to perform the methods provided in the various optional implementations described above.

[0041] In another aspect, embodiments of the present invention also provide a computer-readable medium, which may be included in the electronic device described in the above embodiments; or it may exist independently and not assembled into the electronic device. The computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to perform the methods described in the above embodiments.

Claims

1. A method for anechoic chamber calibration and verification of a curved phased array antenna, characterized in that, Includes the following steps: S1, Set up a darkroom calibration environment; S2, after installation, can rotate the phased array antenna through the built anechoic chamber calibration environment to achieve azimuth changes from 0 to 360° and elevation changes from 0 to 90°; by adjusting the rotation time, angle and the time of calibration command issued by the debugging computer, the two can work together to traverse the calibration process of all azimuth and elevation. After the calibration process is completed, the calibration results are sent to the flash storage module. S3, execute the calibration process; S4. After calibration, the calibration results are verified by calculating performance indicators, including the port level and G / T value. After the debugging software issues the beamforming command, the ZYNQ software uses the channel amplitude according to equation (1). Channel phase The weights are obtained to compensate for system inconsistencies. The frequency control word is calculated based on the frequency point and clock frequency according to equation (2). The relevant parameters are then sent to the FPGA software. (1)； (2)； Where i represents the channel number. Indicates the desired output frequency. Indicates the working clock, This represents the ratio of antenna gain G to system noise temperature T. The FPGA software weights the AD data using a complex multiplier based on the weights, then accumulates the data, and finally performs orthogonal downconversion and filtering on the accumulated result to complete beamforming. After beamforming, the carrier-to-noise ratio is measured by connecting a spectrum analyzer through the intermediate frequency signal observation port. The effective isotropic radiated power is calculated using equation (3). The outlet surface level is calculated using equation (4). Calculated using equation (5) The value is used to verify whether the calibration results are correct. (3)； +20 (4)； (5)。 2. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 1, characterized in that, In step S1, the establishment of the darkroom calibration environment specifically includes the following sub-steps: Two robotic arms are installed in an anechoic chamber, and their positions are calibrated. The two arms are independently controlled and automatically rotate according to time and angle settings. The first robotic arm is equipped with a horn antenna, which is connected to a signal source outside the anechoic chamber via an RF cable. The horn antenna's normal is aligned with the phased array antenna under test, and it transmits a single-carrier signal. The RF cable loss is [missing information]. The gain of the horn antenna is The frequency of the single-carrier signal transmitted by the signal source is The transmission power is A phased array antenna is mounted on the second robotic arm, and the phased array antenna and the horn antenna are aligned in their normal directions, with a spatial distance of [missing information]. The intermediate frequency signal observation port and network port of the phased array antenna are connected to the spectrum analyzer and debugging computer outside the anechoic chamber, respectively. The debugging computer is equipped with debugging software.

3. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 2, characterized in that, In step S2, the phased array antenna can be rotated in the constructed anechoic chamber calibration environment, achieving azimuth changes from 0 to 360° and elevation changes from 0 to 90°. This is achieved by adjusting the rotation time, angle, and the timing of calibration commands issued by the computer. Specifically, this includes: The second robotic arm rotates the phased array antenna to achieve azimuth changes from 0 to 360°, and the second robotic arm itself can rotate to achieve pitch changes from 0 to 90°. The timing and angle of the second robotic arm's rotation are adjusted, as well as the timing of calibration commands issued by the computer.

4. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 1, characterized in that, In step S2, the storage module includes a storage flash.

5. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 1, characterized in that, In step S3, the calibration process specifically includes the following sub-steps: S31: After the debugging software issues calibration commands according to the azimuth and elevation traversal, the ZYNQ software sets and issues calibration-related parameters for each channel, with the frequency control word being a fixed value. S32: After receiving the relevant calibration parameters, the FPGA software weights the real and imaginary AD data in the digital domain using a complex multiplier, then accumulates them, and then downconverts and filters the accumulated results to form reference beam data and calibration beam data. S33: Perform phase and amplitude calibration calculations; S34: After receiving the data calculated by the FPGA calibration, the ZYNQ software performs an arctangent operation on the phase to convert it into degrees, thus obtaining the calibrated phase; it then performs a square root operation on the ratio of the amplitudes; and finally sends the calibration result to the debugging software. S35: After confirming the calibration results, the debugging software sends out the calibration results, and the ZYNQ software writes the calibration results to the storage flash. S36: Turn off the signal source. If the reference channel number issued by the debugging software is modified to a selected channel number, that is, the reference channel phase is a DC signal, the antenna transmits the corresponding frequency signal through the internal channel, which is coupled to the AD channel through the antenna subarray. Repeat the process of steps S32-S34 to detect whether the internal phase of each channel of the antenna has changed and to verify whether the internal hardware state of the antenna has changed.

6. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 5, characterized in that, In step S31, the calibration-related parameters specifically include: reference channel number, calibration channel number, frequency control word, reference beam reference channel weight, and calibration beam channel weight.

7. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 5, characterized in that, In step S33, the phase calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data, and low-pass filtering and comb filtering are combined to achieve selective enhancement and noise suppression of the frequency band signal; second, conjugate operation is performed; and finally, time-domain integration and periodic reset are performed again.

8. The anechoic chamber calibration and verification method for curved phased array antennas according to claim 5, characterized in that, In step S33, the amplitude calibration calculation includes the following sub-steps: first, time-domain integration and periodic reset are performed on the reference and calibration beam data; then, the real and imaginary parts of the reference and calibration beams are respectively subjected to the sum of squares operation; and finally, time-domain integration and periodic reset are performed again.

9. An anechoic chamber calibration and verification device for a curved phased array antenna, characterized in that, It includes a processor and a memory, wherein the memory stores a computer program that, when loaded by the processor, executes the method as described in any one of claims 1 to 8.

10. An anechoic chamber calibration and verification system for a curved phased array antenna, characterized in that, The device includes the anechoic chamber calibration and verification apparatus for the curved phased array antenna as described in claim 9.

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