A method and system for testing phase difference of a variable frequency phased array antenna

Abstract

The application discloses a variable frequency phased array antenna phase difference test method and system, and relates to the technical field of radio frequency test. The test method comprises the following steps: respectively calibrating the phase error of a transmitting and receiving chain link matrix switch and generating a compensation table; during transmission test, the net signal is transmitted to the net through frequency conversion, a TR component, a phased array antenna, a reflecting surface and a feed antenna, and the transmitting phase difference is obtained after compensating the switch error; during reception test, the net excitation is transmitted to the net through the feed antenna, the reflecting surface, the phased array antenna, the TR component and the frequency conversion, and the receiving phase difference is obtained after compensating the switch error. The application does not need a special variable frequency net, ensures the test precision through switch error calibration and compensation, realizes integrated automatic test, adapts to real scenes, reduces the cost and improves the efficiency, and is suitable for the research and development and production test of variable frequency phased array antennas.

Description

Technical Field

[0001] This invention relates to the field of radio frequency testing and multi-channel frequency conversion components, specifically to a phase difference testing method and system for frequency conversion phased array antennas. Background Technology

[0002] In phased array radar and multi-channel wireless communication systems, the frequency conversion phased array antenna is the core hardware. It is usually composed of multiple 1-to-N (positive integer multiples of 2) TR components and multi-channel independent frequency conversion modules. Each TR component is connected to one channel of the frequency conversion module. Each channel of the frequency conversion module contains an independent up-conversion transmission channel and an independent down-conversion reception channel. The phase consistency between the channels directly determines the system's beam pointing accuracy, signal synthesis quality, and airspace coverage capability.

[0003] Existing phase testing solutions for such frequency-converting phased array antenna systems suffer from several technical bottlenecks: First, they require dedicated vector network analyzers that support frequency-converting phase measurement, resulting in high equipment procurement costs, poor versatility, and significantly increased R&D and production costs. Second, if matrix switches are used to automatically switch between multiple frequency-converting channels and multiple TR component signals, the inherent phase inconsistencies between different channels of the switch matrix introduce additional phase errors, leading to low test accuracy and failing to meet the phase consistency requirements of frequency-converting phased array antennas. Third, they cannot achieve integrated testing of transmit and receive phase differences for frequency-converting phased array architectures, requiring two separate test systems, which is cumbersome and inefficient. Fourth, they lack effective methods for eliminating phase errors in the switch matrix and do not separately calibrate and compensate for the transmit and receive links, making it difficult to balance test efficiency and accuracy. Fifth, existing solutions are not adapted to the actual test scenarios of reflectors and feed antennas, and cannot accurately test the true performance of frequency-converting phased array antennas. Summary of the Invention

[0004] This invention addresses the specific architecture of frequency-converting phased array antenna systems by proposing a phase difference testing scheme that employs a matrix switch to switch channels, eliminates switching errors through calibration compensation at the transmitting and receiving ends, adapts to ordinary vector network antennas, and combines the phase difference test of the reflector and feed antenna. This scheme overcomes the shortcomings of existing technologies, balances testing efficiency and accuracy, and fully meets the real hardware testing requirements of frequency-converting phased array antennas.

[0005] The specific solution of this invention is: a phase difference testing system for a frequency-converting phased array antenna, comprising: A vector network analyzer, used as a test excitation source and phase data acquisition terminal; A matrix switch, covering frequencies from DC to 20GHz, enables automatic time-division switching of multiple frequency conversion channels. It connects multiple frequency conversion channels to the test link, allowing switching of multiple transmit signals corresponding to multiple frequency conversion channels in the transmit link and switching of multiple receive signals corresponding to multiple frequency conversion channels in the receive link, replacing manual cable switching and improving test efficiency. Simultaneously, in conjunction with an error calibration and compensation module, it eliminates the inherent phase errors introduced by different channels in the transmit and receive links, adapting to the multi-channel test requirements of frequency conversion phased array antennas.

[0006] A frequency conversion phased array antenna system under test includes a phased array antenna, a reflector, at least one multi-channel frequency conversion module, and multiple TR components; each channel of the multi-channel frequency conversion module independently includes an up-conversion link and a down-conversion link, and each channel is respectively connected to one of the TR components. One reverse frequency conversion module is the same multi-channel frequency conversion module, but only one channel is used to downconvert the high-frequency signal transmitted by the phased array antenna to the intermediate frequency received by the vector network, or to upconvert the intermediate frequency signal transmitted by the vector network to a high-frequency signal for the frequency conversion phased array antenna to receive, and then downconvert it to an intermediate frequency signal for the vector network after passing through the multi-channel frequency conversion module. A feed antenna, connected to an inverting frequency conversion module and a general-purpose vector network analyzer, is used to receive signals reflected by the reflector and transmit them to the inverting frequency conversion module, or to receive signals output by the inverting frequency conversion module and transmit them to the reflector. A control computing unit, configured as follows: The matrix switch is controlled to switch channels, and the relative phase error of each channel in the direction of transmitting signal flow and receiving signal flow is pre-calibrated to generate an error compensation table; and based on the phase data collected by the general vector network analyzer, combined with the error compensation table, the phase difference between the transmitting and receiving channels is calculated after offsetting the common mode error of the receiving end or transmitting end and the phase error of the matrix switch.

[0007] For the direction of the transmitted signal, the output terminal of the vector network analyzer is connected to the common terminal of the matrix switch, and each branch port is connected to the receiving terminal of the vector network analyzer through an equal phase cable. By selecting each channel one by one and measuring the phase, the relative phase error of each channel is calculated and stored with one of them as a reference, forming a transmission error compensation table. For the direction of the received signal, the output of the vector network analyzer is connected to each port of the matrix switch via an equal phase cable, and the common terminal is connected to the receiving end of the vector network analyzer. By selecting each channel one by one and measuring the phase, the relative phase error of each channel is calculated and stored using one of the channels as a reference, thus forming a receiving error compensation table.

[0008] During the test of the transmission phase difference, the first test link is established, so that the intermediate frequency signal emitted by the vector network analyzer is transmitted through the matrix switch, the up-conversion link of the multi-channel frequency conversion module under test, the TR component, and the phased array antenna, and then through the reflector, the feed antenna, and the down-conversion link of the reverse frequency conversion module, and returns to the vector network analyzer. Based on the phase values ​​of each channel collected, the matrix switch error is deducted by combining the error compensation table, and the common mode characteristic of the same receiving path is used to cancel the receiving end error, and the transmission channel phase difference is calculated. When testing the received phase difference, a second test link is established, so that the intermediate frequency signal emitted by the vector network analyzer passes through the up-conversion link of the reverse conversion module, the feed antenna, the reflector, the phased array antenna, the TR component, the down-conversion link of the multi-channel conversion module under test, and the matrix switch, and returns to the vector network analyzer. Based on the collected phase values ​​of each channel, the matrix switch error is deducted by combining the error compensation table, and the common mode characteristic of the same transmission path is used to cancel the transmitter error, and the received channel phase difference is calculated.

[0009] As a preferred embodiment of the present invention, the general-purpose vector network analyzer, as a test excitation source and phase data acquisition terminal, only has basic radio frequency signal output, amplitude and phase measurement functions, and does not require the installation of frequency conversion measurement options, which greatly reduces the threshold of test equipment and adapts to system test requirements.

[0010] In a preferred embodiment of the present invention, the frequency-converting phased array antenna system under test is as follows: (1) TR component: Each TR component adopts a 1-to-N (positive integer multiple of 2) structure, which has the ability to adjust the phase offset of each of its own transmit and receive channels. Each TR component is connected to an independent channel of the multi-channel frequency conversion module to realize multiple transmit and receive frequency conversion channels, corresponding to the signal interface of the phased array antenna. (2) Multi-channel frequency conversion module: It contains multiple completely independent transceiver channels. Each channel has the same structure and is equipped with one up-conversion module (responsible for transmitting signal frequency conversion) and one down-conversion module (responsible for receiving signal frequency conversion). The up-conversion and down-conversion modules of each channel are synchronously locked with the same source local oscillator to ensure the consistency of frequency conversion phase. (3) Phased array antenna: It converts multiple electrical signals output by multiple TR components into electromagnetic signals, or receives external electromagnetic signals and converts them into electrical signals for transmission to TR components. It is the signal transceiver terminal of the frequency conversion phased array system. (4) Reflector: It is responsible for reflecting the multiple electromagnetic signals emitted by the phased array antenna into parallel waves and sending them to the feed antenna, or reflecting the electromagnetic signals emitted by the feed antenna into parallel waves and sending them to the phased array antenna, simulating the signal transmission path in the real working scenario of the frequency conversion phased array antenna.

[0011] As a preferred embodiment of the present invention, the reverse frequency conversion module is an identical multi-channel frequency conversion module, using only one channel to down-convert the high-frequency signal transmitted by the phased array antenna to the intermediate frequency received by the vector network scattering system (VRF), or to up-convert the intermediate-frequency signal transmitted by the VRF into a high-frequency signal for the frequency-converted phased array antenna to receive. After being down-converted to an intermediate-frequency signal by the multi-channel frequency conversion module and transmitted to the VRF, the same-frequency phase measurement is achieved.

[0012] In a preferred embodiment of the present invention, the feed antenna is connected to the reverse frequency conversion module and the general vector network analyzer, and is used to receive the signal reflected by the reflector and transmit it to the reverse frequency conversion module, or to receive the signal output by the reverse frequency conversion module and transmit it to the reflector, thereby completing the transmission and reception relay of the test signal of the frequency conversion phased array antenna.

[0013] In a preferred embodiment of the present invention, the control and computing unit, namely the engineering test computer, includes automated test software and is connected to a general-purpose vector network analyzer and a matrix switch to complete phase data acquisition, matrix switch phase error calibration, error compensation, phase difference calculation, and test report output. At the same time, it can guide the adjustment of the phase shifter of the TR component based on the phase difference test results to ensure the phase consistency of the frequency conversion phased array antenna.

[0014] Compared with existing technologies, this invention is fully compatible with the hardware architecture of frequency conversion phased array antenna systems, incorporates real-world testing scenarios for reflectors and feed antennas, and specifically addresses the matrix switching phase error problem, as follows: 1. Innovative Channel Architecture: The device under test is a frequency conversion phased array antenna system, which consists of multiple 1-to-N (positive integer multiples of 2) TR components and multi-channel independent frequency conversion modules. Each frequency conversion channel has its own up-conversion (transmit) and down-conversion (receive) modules. There is no centralized frequency conversion module, which realizes complete independence of multi-channel transmission and reception and is adapted to the actual hardware structure of frequency conversion phased array antennas. 2. Switching and Error Elimination: A DC-20GHz matrix switch is used to achieve automatic switching of multiple frequency conversion channels, thereby enabling time-division testing of multiple TR component signals and improving testing efficiency. At the same time, the phase error of the matrix switch is calibrated for the transmit and receive links respectively, and corresponding error compensation tables are generated. Real-time compensation is performed during testing to completely eliminate the phase deviation caused by different channels of the matrix switch, balancing efficiency and accuracy to meet the high-precision testing requirements of frequency conversion phased array antennas. 3. Transmission Test Principle: The vector network analyzer outputs an intermediate frequency (IF) excitation signal, which is switched by a matrix switch to the upconversion module of the frequency conversion module. The upconversion module upconverts the IF signal to a high frequency signal, which is then transmitted to the TR (Transmission Transformer) component. The TR component expands the signal into multiple transmit signals, which are then input to the frequency-converted phased array antenna. The multiple high-frequency signals transmitted by the phased array antenna are reflected as parallel waves by a reflector and received by the feed antenna, then transmitted to the inverse frequency conversion module. The inverse frequency conversion module downconverts the high-frequency signal to an IF signal and transmits it to the vector network analyzer receiver. All phase errors (including switch matrix errors) in the receiver cable, inverse frequency conversion module, matrix switch, and vector network analyzer receiver are eliminated through a dual method of single-channel common-mode characteristic and switch error compensation. The final phase difference only reflects the actual difference between the multiple transmit channels (upconversion + TR component) and is used to adjust the phase shifter at the transmitter end of the TR component to ensure the phase consistency of the frequency-converted phased array antenna. 4. Reception Test Principle: The vector network analyzer outputs an intermediate frequency (IF) excitation signal, which is transmitted to the inverting frequency conversion module. The inverting frequency conversion module upconverts the signal to a high-frequency signal, which is then transmitted to the reflector via the feed antenna. The reflector reflects the signal as a parallel wave to the frequency-converting phased array antenna. The multiple high-frequency signals received by the phased array antenna are transmitted to the downconversion module of the frequency conversion module via the TR component. The downconversion module downconverts the high-frequency signals to an IF signal, which is then switched by a matrix switch and time-division multiplexed to the vector network analyzer receiver. All inherent errors (including switch matrix errors) of the transmitting cable, inverting frequency conversion module, feed antenna, and reflector are canceled by common mode and compensated for by switch errors. The final phase difference only reflects the actual difference of the multiple receiving channels (downconversion + TR component), and is used to adjust the phase shifter at the TR component receiver to ensure the phase consistency of the frequency-converting phased array antenna. 5. Innovative Equipment Adaptation: The entire process uses a standard vector network analyzer, eliminating the need for a dedicated frequency-converting vector network analyzer. It achieves the conversion between high-frequency and intermediate-frequency signals through a reverse frequency conversion module, adapting to the same-frequency phase measurement logic of a standard vector network analyzer, thus significantly reducing the testing equipment cost for frequency-converting phased array antennas. 6. Innovative Scenario Adaptation: By integrating the reflector and feed antenna, it fully simulates the real working scenario of the frequency conversion phased array antenna. The test results are more in line with the actual application requirements, making it more practical and directly applicable to the research, development, production, and testing of frequency conversion phased array antennas. Attached Figure Description

[0015] Figure 1 This is an overall block diagram of the frequency conversion phased array antenna phase difference testing system of the present invention; Figure 2 This is a flowchart of the phase error calibration process for the transmitter matrix switch of the present invention; Figure 3 This is a flowchart of the phase error calibration process for the matrix switch at the receiving end of the present invention. Figure 4 This is a flowchart of the phase difference test process for the transmission channel of the present invention; Figure 5 This is a flowchart of the phase difference test process for the receiving channel of the present invention. Detailed Implementation

[0016] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0017] like Figure 1 As shown, this embodiment takes a 16TR frequency conversion phased array antenna as an example. There are a total of 4 1-to-4 TR components. Each TR component is connected to one channel of the 4-frequency conversion module. Each channel of the frequency conversion module includes an up-converted transmit channel and a down-converted receive channel. The intermediate frequency band is 1.7GHz and the high frequency band is 17GHz.

[0018] 1. System Hardware Components General-purpose vector network analyzer: It only has basic RF signal output, amplitude and phase measurement functions, and does not require frequency conversion measurement options.

[0019] Frequency conversion phased array antenna: TR component: Internally splits into four, capable of adjusting the phase offset of the four transmit and receive channels. 4-channel frequency converter module: Contains 4 completely independent transceiver channels, each with the same structure: Independent up-conversion module and independent down-conversion module.

[0020] Array antenna: converts multiple signals into electromagnetic signals.

[0021] Matrix switch: Connects the transceiver channel of the frequency converter module, with a frequency range of DC to 20GHz.

[0022] Reflector: Responsible for reflecting the 16 signals from the phased array antenna into parallel waves for the source antenna, or reflecting the signals transmitted by the feed antenna into parallel waves for the phased array antenna. Reverse frequency conversion module: This is a 4-channel frequency conversion module. Only one channel is used to downconvert the high-frequency signal transmitted by the antenna to the vector network intermediate frequency (VRF), or to upconvert the low-frequency signal transmitted by the VRF to the high-frequency signal received by the phased array antenna. After being downconverted to an intermediate frequency signal by the 4-channel frequency conversion module, it is sent to the VRF intermediate frequency to achieve co-frequency phase measurement.

[0023] Feed antenna: Connects the reverse frequency conversion module and the vector network, used for receiving and transmitting signals.

[0024] Control and Calculation Unit: The industrial computer runs automated testing software to complete phase acquisition, error compensation, phase difference calculation, and report output.

[0025] like Figure 2 As shown: Transmitter matrix switch phase error calibration: Connection method: Vector network output (Port A) → Matrix switch common terminal → Matrix switch 4-channel output → Equal length RF cable → Vector network receiver (Port B).

[0026] Vector network setup: Frequency: 1.7GHz, Test power: -10dBm, Measurement parameter: Phase.

[0027] Test procedure: Sequentially switch the four channels of the matrix switch and record the phase as follows: TX_φ_switch1; TX_φ_switch2; TX_φ_switch3; TX_φ_switch4; Using channel 1 as the reference, calculate the relative phase error between each channel and channel 1: TX_Δφ_switch1 (result is 0); TX_Δφ_switch2; TX_Δφ_switch3; TX_Δφ_switch4; Generate a matrix switch transmit phase error compensation table and store it in the test software for subsequent real-time compensation.

[0028] like Figure 3 As shown: Phase error calibration of the receiver matrix switch Connection method: Vector network output (Port A) → Equal length RF cable → 4-channel output of matrix switch → Common terminal of matrix switch → Vector network receiver (Port B).

[0029] Vector network settings: frequency 1.7GHz, test power: -10dBm, measurement parameter: phase.

[0030] Test procedure: Sequentially switch the four channels of the matrix switch and record the phase as follows: RX_φ_switch1; RX_φ_switch2; RX_φ_switch3; RX_φ_switch4; Using channel 1 as a reference, calculate the relative phase error: RX_Δφ_switch1 (result is 0); RX_Δφ_switch2; RX_Δφ_switch3; RX_Δφ_switch4; A phase error compensation table for the matrix switch receiver is generated and stored in the test software for subsequent real-time compensation.

[0031] like Figure 4 As shown: Transmission channel phase difference test System connection: Vector network output (Port A) → Matrix switch common terminal → Matrix switch 4-channel output → Equal length RF cable → 4-channel frequency conversion module TX_in (transmit signal input) → 4 1-to-4 TR components → 16TR phased array antenna → Reflector → Feed antenna → Down-conversion test channel → Vector network receiver (Port B).

[0032] Vector network settings: frequency 1.7GHz, test power: -10dBm, measurement parameter: phase.

[0033] Test steps: Upon system power-up, the local oscillator of the four channels of the frequency converter module and the down-conversion test channel are synchronously locked. Turn on the receive switch of the reverse downconversion test channel, switch the transmit link matrix switch channel, and control the four transmit channels of the TR component connected to this channel to turn on sequentially, and measure the phase of the four transmit channels: TX_φ1~TX_φ4, Similarly, the 12 transmit phases of TR components 2~4 were measured sequentially: TX_φ5~TX_φ16. Subtract the matrix switch transmit phase error respectively. Among them, TX_φ1~TX_φ4 need to be subtracted from TX_Δφ_switch1; Among them, TX_φ5~TX_φ8 need to be subtracted from TX_Δφ_switch2; Among them, TX_φ9~TX_φ12 need to be subtracted from TX_Δφ_switch3; Among them, TX_φ13~TX_φ16 need to be subtracted from TX_Δφ_switch4; That is, the phase difference of the transmission channel: TX_Δφ1=TX_φ1-TX_Δφ_switch1, TX_Δφ2=TX_φ2-TX_Δφ_switch1, TX_Δφ3=TX_φ3-TX_Δφ_switch1, TX_Δφ4=TX_φ4-TX_Δφ_switch1, ... TX_Δφ13=TX_φ13-TX_Δφ_switch4; TX_Δφ14=TX_φ14-TX_Δφ_switch4; TX_Δφ15=TX_φ15-TX_Δφ_switch4; TX_Δφ16=TX_φ16-TX_Δφ_switch4; Since the receiving ends share the same receiving link, the transmit phase offset of the device under test is: TX_Δφ1~TX_Δφ16; Based on the above results, the phase shifter at the transmitter end of the TR component is adjusted to ensure the phase consistency of the phased array antenna.

[0034] like Figure 5 As shown: Receive channel phase difference test System connection: Vector network output (Port A) → Upconversion test channel → Feed antenna → Reflector → 16TR phased array antenna → 4 TR components → RX_out (received signal output) of 4-channel frequency conversion module → Equal length RF cable → 4 inputs of matrix switch → Common terminal of matrix switch → Vector network receiver (Port B).

[0035] Vector network setup: Frequency: 1.7GHz, Test power: -10dBm, Measurement parameter: Phase.

[0036] Test procedure: Power on the system, and lock the local oscillator of the four channels of the frequency converter module and the up-conversion test channel synchronously; Turn on the transmit switch of the upconversion test channel, switch the receive link matrix switch channel 1, and control the TR component connected to this channel to turn on the 4 receivers in sequence, and measure the phase of the 4 receivers: RX_φ1~RX_φ4, Similarly, RX_φ5~RX_φ16 were measured sequentially. Subtract the phase error of the matrix switch receiver respectively. Among them, RX_Δφ_switch1 needs to be subtracted from RX_φ1~RX_φ4; Among them, RX_φ5~RX_φ8 need to be subtracted from RX_Δφ_switch2; Among them, RX_φ9~RX_φ12 need to be subtracted from RX_Δφ_switch3; Among them, RX_φ13~RX_φ16 need to be subtracted from RX_Δφ_switch4; That is, the phase difference of the receiving channel: RX_Δφ1=RX_φ1-RX_Δφ_switch1, RX_Δφ2=RX_φ2-RX_Δφ_switch1, RX_Δφ3=RX_φ3-RX_Δφ_switch1, RX_Δφ4=RX_φ4-RX_Δφ_switch1, ... RX_Δφ13=RX_φ13-RX_Δφ_switch4, RX_Δφ14=RX_φ14-RX_Δφ_switch4, RX_Δφ15=RX_φ15-RX_Δφ_switch4, RX_Δφ16=RX_φ16-RX_Δφ_switch4, Since the transmitting ends share the same transmission link, the receiving phase offset of the device under test is: RX_Δφ1~RX_Δφ16, Based on the above results, the phase shifter at the receiver of the TR component is adjusted to ensure the transmit phase consistency of the phased array antenna.

[0037] The technical effects that can be achieved through the above embodiments are as follows: The entire process uses only a standard vector network analyzer, without the need for a dedicated frequency conversion phase test function; The matrix switch automatically switches, reducing testing time by more than 75%. The switching phase error is completely eliminated through calibration compensation, and the phase accuracy is ≤ 3°; A single system can simultaneously perform overall phase error testing of the transmit and receive functions of a frequency conversion phased array antenna system. It perfectly matches the real hardware architecture and is highly targeted.

[0038] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A phase difference testing system for a frequency-converting phased array antenna, characterized in that, include: A vector network analyzer, used as a test excitation source and phase data acquisition terminal; A matrix switch connects multiple frequency converter channels to the test link, and is used to switch multiple transmit signals corresponding to multiple frequency converter channels in the transmit link and switch multiple receive signals corresponding to multiple frequency converter channels in the receive link. A frequency conversion phased array antenna system under test includes a phased array antenna, a reflector, at least one multi-channel frequency conversion module, and multiple TR components; each channel of the multi-channel frequency conversion module independently includes an up-conversion link and a down-conversion link, and each channel is respectively connected to one of the TR components. One reverse frequency conversion module is the same multi-channel frequency conversion module, but only one channel is used to downconvert the high-frequency signal transmitted by the phased array antenna to the intermediate frequency received by the vector network, or to upconvert the intermediate frequency signal transmitted by the vector network to a high-frequency signal for the frequency conversion phased array antenna to receive, and then downconvert it to an intermediate frequency signal for the vector network after passing through the multi-channel frequency conversion module. A feed antenna, connected to an inverting frequency conversion module and a general-purpose vector network analyzer, is used to receive signals reflected by the reflector and transmit them to the inverting frequency conversion module, or to receive signals output by the inverting frequency conversion module and transmit them to the reflector. A control computing unit, configured as follows: The matrix switch is controlled to switch channels, and the relative phase error of each channel of the matrix switch in the direction of transmitting signal flow and receiving signal flow is pre-calibrated to generate an error compensation table; Based on the phase data collected by the general-purpose vector network analyzer, and combined with the error compensation table, the phase difference between the transmit and receive channels is calculated after offsetting the common-mode error of the receiver or transmitter and the phase error of the matrix switch.

2. The testing system according to claim 1, characterized in that, The process by which the control calculation unit performs the pre-calibration is specifically as follows: For the direction of the transmitted signal, the output terminal of the vector network analyzer is connected to the common terminal of the matrix switch, and each branch port is connected to the receiving terminal of the vector network analyzer through an equal phase cable. By selecting each channel one by one and measuring the phase, the relative phase error of each channel is calculated and stored with one of the channels as a reference, and a transmission error compensation table is formed. For the direction of the received signal, the output of the vector network analyzer is connected to each port of the matrix switch via an equal phase cable, and the common terminal is connected to the receiving end of the vector network analyzer. By selecting each channel one by one and measuring the phase, the relative phase error of each channel is calculated and stored using one of the channels as a reference, thus forming a receiving error compensation table.

3. The testing system according to claim 1, characterized in that, The process by which the control calculation unit performs the calculation of the phase difference between the transceiver channels is specifically as follows: When testing the transmission phase difference, the first test link is established, so that the intermediate frequency signal emitted by the vector network analyzer is transmitted through the matrix switch, the up-conversion link of the multi-channel frequency conversion module under test, the TR component, and the phased array antenna, and then returns to the vector network analyzer through the reflector, the feed antenna, and the down-conversion link of the reverse frequency conversion module. Based on the collected phase values ​​of each channel, the matrix switch error is deducted by combining the error compensation table, and the receiver error is canceled by using the common mode characteristic of the same receiving path, and the phase difference of the transmitting channel is calculated. When testing the received phase difference, a second test link is established, so that the intermediate frequency signal emitted by the vector network analyzer passes through the up-conversion link of the reverse frequency conversion module, the feed antenna, the reflector, the phased array antenna, the TR component, the down-conversion link of the multi-channel frequency conversion module under test, and the matrix switch, and returns to the vector network analyzer. Based on the collected phase values ​​of each channel, the matrix switch error is deducted by combining the error compensation table, and the common mode characteristic of the same transmission path is used to cancel the transmitter error, and the phase difference of the receiving channel is calculated.

4. The testing system according to claim 3, characterized in that, In the multi-channel frequency converter module under test, all independent up-conversion links and down-conversion links share the same local oscillator source and are synchronously locked to ensure the phase consistency of each channel's frequency conversion link.

5. The testing system according to claim 1, characterized in that, The TR component is a 1-to-N structure, where N is a positive integer power of 2. It has an adjustable phase shifter inside, which is used to compensate and adjust the phase offset of each branch signal according to the phase difference between the transmit and receive channels calculated by the control calculation unit.

6. The testing system according to claim 3, characterized in that, In the multi-channel frequency converter module under test, the phased array antenna converts the multiple electrical signals output by multiple TR components into electromagnetic signals, or receives external electromagnetic signals and converts them into electrical signals for transmission to the TR components, serving as the signal transceiver terminal of the frequency converter phased array system. The reflector is responsible for reflecting the multiple electromagnetic signals emitted by the phased array antenna into parallel waves and sending them to the feed antenna, or reflecting the electromagnetic signals emitted by the feed antenna into parallel waves and sending them to the phased array antenna, thus simulating the signal transmission path in the real working scenario of the frequency conversion phased array antenna.

7. A method for testing the phase difference of a frequency-converting phased array antenna, implemented based on the system described in any one of claims 1-6, characterized in that, include: Transmitter matrix switch phase error calibration: Connect the vector network output terminal to the common terminal of the matrix switch, and connect each output terminal of the matrix switch to the vector network receiver through cables of equal length. Switch the matrix switch channels one by one, measure the phase value of each channel, calculate the relative phase error with the first channel as the reference, generate a transmitter error compensation table and store it. Receiver matrix switch phase error calibration: Connect the vector network output terminal to each output terminal of the matrix switch through cables of equal length, connect the common terminal of the matrix switch to the vector network receiver, switch the matrix switch channels one by one, measure the phase value of each channel, calculate the relative phase error with the first channel as the reference, generate the receiver error compensation table and store it. Transmit channel phase difference test: The vector network input signal is up-converted by a matrix switch and a multi-channel frequency conversion module, and output to the phased array antenna by the TR component. It is then transmitted to the vector network receiver through the receiving channel of the reflector, feed antenna, and reverse frequency conversion module. The phase value is collected channel by channel, the error compensation table of the transmitter is called to deduct the switch error, and the common mode error of the receiver is offset to obtain the true phase difference of the transmit channel. The phase shifter of the TR component transmitter is then adjusted. Receive channel phase difference test: The vector network input signal is transmitted through the transmit channel of the reverse frequency conversion module to the feed antenna, reflector, phased array antenna, TR component, down-conversion of the multi-channel frequency conversion module, matrix switch and transmitted to the vector network receiver. The phase value is collected for each channel, the error compensation table of the receiver is called to deduct the switch error and cancel the common mode error of the transmitter to obtain the true phase difference of the receive channel. The phase shifter of the TR component receiver is then adjusted.

8. The test method according to claim 7, characterized in that: The parameters for calibrating the phase error of the matrix switches at the transmitting and receiving ends are consistent with those in the formal test, and are recalibrated once before each daily test; the phase difference test of the transmitting and receiving channels is also conducted.

9. The test method according to claim 7, characterized in that: The common-mode error includes cable delay, inverter phase drift, matrix switch switching error, and inherent deviation of the receiver of the general vector network analyzer. It is completely offset by the dual means of common-mode characteristics and switch error compensation in the same receiving link or the same transmitting link.

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