Phased array antenna active standing wave test method and test system

Abstract

The application provides a phased array antenna active standing wave test method and a test system, relates to the technical field of antenna testing, is applied to a control unit of a test system, and the test system further comprises a phase synchronization device, a multi-channel signal source, a switch network, a vector network analyzer and a directional coupling component connected in series in an excitation path. First, the phase synchronization device is controlled to synchronize each radio frequency channel to establish a phase reference, and then the switch network is switched to obtain channel basic parameters and component system errors, and calibration end face correction parameters for compensating amplitude and phase deviation are generated. Then, based on the parameters, each channel is controlled to synchronously output excitation signals to the phased array antenna to be tested, incident and reflected signals are collected, and active standing wave data is calculated according to the vector ratio. The application can ensure the simulation of real working conditions of full-array simultaneous excitation, unify the calibration end face to the antenna port to eliminate the fixed phase deviation of the link, correct the parameters once to realize repeated calibration-free at multiple frequency points and in multiple states, and significantly improve the test precision and efficiency.

Description

Technical Field

[0001] This invention relates to the field of antenna testing technology, and in particular to a method and system for testing active standing waves of phased array antennas. Background Technology

[0002] In the transmitting or receiving state, phased array antennas exhibit electromagnetic energy coupling between their individual antenna elements, known as mutual coupling. This mutual coupling alters the impedance matching characteristics of the antenna elements, thereby affecting the beamform and gain of the array. The mismatch between antenna elements caused by mutual coupling generates active standing waves (VSWs). While reducing the antenna's radiated power, these SSWs increase the power handling capacity of the transmitting / receiving components, posing a potential threat to their long-term safety. Therefore, active standing wave parameters are a key indicator for evaluating the performance of phased array antennas.

[0003] Currently, the testing of active standing wave ratio (VSWR) parameters typically relies on a combination of a vector network analyzer and a switching matrix. During testing, the test ports of the vector network analyzer are connected to the antenna element under test (DUT), while the remaining ports are terminated with matching loads. The switching matrix sequentially switches the ports, measuring the reflection coefficient of each element and calculating the VSWR. For multi-channel testing requirements, multiple signal sources are typically used to output excitation signals separately. However, since each signal source operates independently, the relative phase relationship between their output signals is uncertain.

[0004] However, the aforementioned existing technologies have significant drawbacks. First, port-by-port testing cannot simulate the real-world operating condition where all units are simultaneously excited, leading to an underestimation of the active standing wave ratio (VSWR) and affecting component safety assessment. Second, in conventional multi-channel systems, the initial phase of each channel is not fixed upon power-on, making it difficult to accurately reproduce the phase distribution required for beam scanning, resulting in distortion of the excitation state. Third, the reference plane definition in existing calibration methods is inaccurate, leading to systematic biases in the measurement results. Furthermore, repeated calibration is required during multi-frequency or multi-scan testing, resulting in low testing efficiency and making it difficult to meet the timeliness requirements of large-scale array engineering testing. Summary of the Invention

[0005] This invention provides a method and system for testing active standing waves of phased array antennas, which solves the technical problems of existing active standing wave testing methods for phased array antennas, such as the inability to simulate the real working conditions of the entire array surface, uncontrollable excitation phase, low calibration accuracy, and poor testing efficiency.

[0006] This invention provides a method for testing active standing waves (VSWR) of a phased array antenna, applied to the control unit of a test system. The test system further includes a phase coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. The method includes: The phase-coherent synchronization device is controlled to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with a fixed initial phase. By switching the test path of the switching network, the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component are obtained respectively, and calibration end face correction parameters are generated to compensate for the amplitude and phase deviation of each excitation channel. Based on the calibration end face correction parameters, the excitation signals of each RF channel are synchronously output and applied to the phased array antenna under test. The incident and reflected signals extracted by the directional coupling component are collected by the vector network analyzer. The active standing wave test data of the phased array antenna under test are calculated based on the vector ratio of the incident signal and the reflected signal.

[0007] According to the present invention, an active standing wave (VSWR) test method for a phased array antenna is provided, wherein controlling the phase coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with an initial fixed phase includes: The coherent synchronization device distributes a common reference clock and a synchronization trigger signal to the multi-channel signal source, so that each radio frequency channel outputs an initial coherent signal based on the common reference clock and at the edge of the synchronization trigger signal. Read the pre-stored phase calibration data and perform reverse compensation on the fixed phase deviation of each radio frequency channel in the initial phase coherent signal, so that the compensated initial phase coherent signal reaches the reference state with the initial phase fixed at the output end.

[0008] According to the active standing wave (VSWR) test method for phased array antennas provided by the present invention, the basic calibration parameters of each excitation channel are obtained by switching the test path of the switching network, including: The first radio frequency channel of the multi-channel signal source is connected to the vector network analyzer via the switching network as a reference channel. With the reference channel remaining connected, the remaining radio frequency channels are sequentially connected to the vector network analyzer via the switch network. The amplitude, phase, and time delay deviations of each excitation channel are determined based on the reference channel and used as the basic calibration parameters. The multi-channel signal source, via the switching network and the directional coupling component, connects to the port of the phased array antenna under test, forming each excitation channel.

[0009] According to the present invention, an active standing wave (VSWR) test method for a phased array antenna is provided, which obtains the system error introduced by the directional coupling component by switching the test path of the switching network, including: The first radio frequency channel is directly connected to the vector network analyzer through the switching network to measure the first phase value; Disconnect the first RF channel from the vector network analyzer, connect the second RF channel in series with the directional coupling component through the switch network to the vector network analyzer, and measure the second phase value. The second RF channel is any RF channel in the multi-channel signal source that is pre-specified other than the first RF channel. The difference between the second phase value and the first phase value is taken as the system error introduced by the directional coupling component.

[0010] According to the active standing wave (VSWR) test method for phased array antennas provided by the present invention, the step of generating calibration endface correction parameters for compensating for amplitude and phase deviations of each excitation channel includes: The calibration end face correction parameters are generated by superimposing the basic calibration parameters and the system error. The calibration end face is the physical interface surface of the port from the switch network output to the phased array antenna under test.

[0011] According to the present invention, an active standing wave (VSWR) test method for a phased array antenna is provided, wherein the step of controlling the synchronous output excitation signal of each radio frequency channel to act on the phased array antenna under test based on the calibration end face correction parameters includes: When the calibration end face correction parameters are in effect, the excitation signal with a preset amplitude and phase distribution is synchronously output by each radio frequency channel, and the excitation signal is simultaneously applied to all array elements of the phased array antenna under test.

[0012] According to the present invention, an active standing wave (VSWR) test method for a phased array antenna is provided, wherein when the number of ports of the phased array antenna under test is greater than the number of radio frequency channels configured in the current multi-channel signal source, the method further includes: The multi-channel signal source and the switching network are cascaded to match the number of ports of the phased array antenna under test. The reference clock and trigger signal are synchronously distributed to all expanded RF channels, and amplitude and phase calibration and error compensation are performed on all expanded excitation channels. The expanded full array is controlled to synchronously output the excitation signal.

[0013] According to the active standing wave (VSWR) test method for phased array antennas provided by the present invention, after generating the calibration end face correction parameters, the method further includes: Keeping the amplitude compensation value and time delay compensation value in the calibration end face correction parameters unchanged, independently configure the phase compensation value of each RF channel to simulate different scanning angles, and synchronously perform antenna pattern testing.

[0014] The present invention also provides a test system comprising: a control unit and a phased-coordinate synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer communicatively connected to the control unit, wherein a directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test, and the control unit is configured to perform any of the above-described active standing wave test methods for phased array antennas.

[0015] The present invention also provides a testing device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the active standing wave test method for phased array antennas as described above.

[0016] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the active standing wave test method for phased array antennas as described above.

[0017] The present invention also provides a computer program product, including a computer program that, when executed by a processor, implements the active standing wave test method for phased array antennas as described above.

[0018] This invention provides a method and system for testing active standing waves (VSWR) of a phased array antenna. The test system is applied to a control unit and includes a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. First, the coherent synchronization device synchronizes each RF channel of the multi-channel signal source to establish a reference state with a fixed initial phase. Then, by switching the test path of the switching network, the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component are obtained, generating calibration end-face correction parameters to compensate for the amplitude and phase deviations of each excitation channel. Based on the calibration end-face correction parameters, each RF channel is controlled to synchronously output excitation signals to the phased array antenna under test. The incident and reflected signals extracted by the directional coupling component are acquired by the vector network analyzer, and the active VSWR test data of the phased array antenna under test is calculated based on the vector ratio of the incident and reflected signals. Therefore, this approach can achieve real-world simulation of simultaneous excitation of all elements across the entire array, ensuring the determinism and repeatability of the relative phase of the output signals from each RF channel. It unifies the calibration endpoint to the physical interface of the antenna port to eliminate fixed phase deviations in the link. Furthermore, once the calibration endpoint correction parameters are generated at once, multi-frequency or multi-scan state tests do not require repeated calibration, thereby significantly improving test accuracy and efficiency. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in this 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 some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the test system provided by the present invention.

[0021] Figure 2 This is a flowchart illustrating the active standing wave test method for phased array antennas provided by the present invention.

[0022] Figure 3 This is a block diagram illustrating the synchronization principle of the vector excitation signal generation subsystem of the present invention.

[0023] Figure 4 This is a schematic diagram illustrating the calibration path switching and error compensation principle provided by the present invention.

[0024] Figure 5 This is a schematic diagram of the signal excitation and standing wave acquisition path provided by the present invention.

[0025] Figure 6 This is a schematic diagram of the test equipment provided by the present invention. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0027] Existing active standing wave (VSWR) testing methods for phased array antennas typically employ a port-by-port excitation approach with the remaining ports connected to matched loads. This method fails to simulate the mutual coupling environment generated by simultaneous excitation of all elements in actual operation, leading to test results deviating from the true active VSWR value. Furthermore, the initial phase of each channel in a conventional multi-channel signal generator is not fixed after power-on, making it difficult to accurately reproduce the phase distribution required for beam scanning. In addition, the inaccurate definition of the reference plane in existing calibration methods results in systematic biases in the measurement results, and repeated calibration is required under multi-frequency or multi-scan conditions, resulting in low testing efficiency.

[0028] To address the aforementioned problems in existing technologies, this invention provides a method and system for testing active standing waves (VSWR) of phased array antennas. The inventive concept is as follows: First, a phase-coherent synchronization device establishes a reference state with fixed initial phases for each RF channel of a multi-channel signal source, ensuring the deterministic and repeatable relative phase of the output signals from each channel. Then, by switching the path of the switching network, the basic calibration parameters of each excitation channel and the system errors introduced by the directional coupling components connected in series on the excitation path are obtained respectively. Correction parameters are generated with the physical interface surface of the antenna port as the calibration endpoint, thereby unifying the calibration reference surface to the antenna port and compensating for the amplitude and phase deviation of the entire link in one go. Finally, based on the calibration endpoint correction parameters, all RF channels are controlled to synchronously output excitation signals, putting the phased array antenna in a true working state of simultaneous excitation of the entire array surface. The incident and reflected signals are extracted using the series-connected directional coupling components to calculate the active standing wave. Therefore, this invention can achieve realistic, accurate, and efficient testing of the active standing wave of a phased array antenna.

[0029] The active standing wave test method and test system for phased array antennas provided by the present invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0030] Figure 1 This is a schematic diagram of the structure of the testing system provided by the present invention, as shown below. Figure 1 As shown, the test system includes: a control unit (such as...) Figure 1 11. Control computer and testing software shown) 12. Multi-channel signal source (such as...) Figure 1 The system includes a vector excitation signal generation subsystem (13), a switch network (14), and a vector network analyzer (15). The control unit (11) is connected to the multi-channel signal source (13), switch network (14), and vector network analyzer (15) via a network switch (16) to uniformly schedule the hardware modules and execute test control logic. The test system also includes a coherent synchronization device. A control connection is established between the control unit (11) and the coherent synchronization device. The coherent synchronization device is used to configure synchronization parameters and initiate the coherent synchronization process. The synchronization signal allocation logic and physical connection architecture of the coherent synchronization device are as follows: Figure 3 As shown in the image.

[0031] Specifically, the multi-channel signal source 13 can be constructed by cascading multiple dual-channel signal generators, for example, 8 devices forming 16 RF channels. Each signal generator includes a baseband processing module and an RF link module. The baseband part is used to generate baseband IQ (In-phase / Quadrature modulation) signals according to the set signal type, such as continuous wave (CW), modulated signal, etc. and format. The IQ signal enters the RF link, and after processing such as broadband IQ modulation, up-conversion, and signal conditioning, the required RF signal is generated from the output port. The signal frequency, power, amplitude, phase, and relative delay of each RF channel can be independently configured and precisely adjusted by software. The coherent synchronization device has a trigger distribution function, distributing a common reference clock (clk) and a synchronous trigger signal (trig) to each signal generator through equal-length cables. The switching network 14 is a multiple-input multiple-output RF matrix used to construct and dynamically switch calibration channel paths and signal excitation channel paths.

[0032] It should be noted that, Figure 1 This is a schematic diagram of the core control and measurement architecture of the test system. In the actual physical link, directional coupling components, such as dual directional coupling devices, are connected in series on each excitation path between the switch network 14 and the phased array antenna under test. These components are passive microwave testing devices used to separate the incident and reflected waves during excitation signal transmission. Their coupling port and isolation port are respectively connected to the receiving port of the vector network analyzer 15. In actual operation, those skilled in the art can adapt and connect directional coupling components to the RF link between the output of the switch network 14 and the antenna port according to the actual test frequency band and power requirements.

[0033] Optionally, the spectrum analyzer 17 and system testing device 18 shown in Figure 1 are optional auxiliary monitoring modules for the test system, used to monitor the spectral purity of the excitation signal and the health status of the system link in real time. They can be configured according to actual engineering needs, and the present invention does not limit them.

[0034] Based on the above Figure 1 The schematic diagram illustrates the test system architecture. This invention provides an active standing wave test method for phased array antennas, in which the control unit of the test system executes the corresponding steps in the method shown below.

[0035] Figure 2 The flowchart of the active standing wave test method for phased array antennas provided by the present invention is shown below. Figure 2 As shown, the method includes: S101. Control the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with a fixed initial phase.

[0036] This step establishes a stable and reproducible underlying phase reference system for subsequent calibration and full-array excitation testing. In active standing wave (VSWR) testing of phased array antennas, the mutual coupling effect and beam pointing of the array elements of the phased array antenna under test are highly dependent on the relative phase distribution between each excitation channel. If the initial phase of the multi-channel signal source drifts randomly during power-on or state switching, it cannot accurately simulate the true phase gradient during antenna scanning, leading to the failure of the test reference. This step sends commands from the control unit to the phase-coherent synchronization device, controlling all RF channels to leave the independent oscillation state and enter a unified frequency and timing control, thereby eliminating phase uncertainty during the power-on phase. It is worth noting that the established reference state with a fixed initial phase does not refer to a fixed absolute phase value, but rather to the deterministic and highly repeatable relative phase relationship between the output signals of each channel, providing a reliable signal source foundation for subsequent switching network path switching, directional coupler error extraction, and active VSWR vector calculation.

[0037] Figure 3 This is a block diagram illustrating the synchronization principle of the vector excitation signal generation subsystem of the present invention. It schematically shows the hardware topology and signal distribution path between the coherent synchronization and triggering device and multiple multi-channel signal generators. In some embodiments, step S101 may include two coordinated stages: hardware timing alignment and software precision compensation.

[0038] Specifically, during the hardware synchronization and alignment phase, the control unit controls the coherent synchronization device to distribute multiple co-source reference clocks and synchronization trigger signals to the multi-channel signal source. For example... Figure 3 As shown, the coherent synchronization device outputs multiple sets, such as 16 sets, of the same source reference clock signals (e.g., ...). Figure 3 CLK in the middle) and synchronous trigger signal (Hardware Trigger Signal, such as Figure 3 (TRIG in the image), each signal is connected to a coaxial cable of equal length, such as... Figure 3The diagram shows two dual-channel signal generators. A common reference clock provides a coherent frequency reference for each RF channel, and a synchronization trigger signal serves as the multi-channel start command. Each RF channel outputs a baseband IQ signal simultaneously upon receiving the edge of the synchronization trigger signal. After being generated in the baseband section, the baseband IQ signal is modulated onto a coherent high-frequency carrier via wideband IQ modulation, ultimately outputting an initial coherent signal. Through hardware mechanisms such as fixed-frequency coherent clock, edge-triggered alignment, and equal-length coaxial cable transmission, the coherence of the multiple RF signals output by the multi-channel signal source is ensured, and the initial phase is deterministic, thereby achieving multi-channel signal synchronization and establishing the synchronization hardware foundation for the entire test system. It should be noted that synchronization control is uniformly scheduled by the control unit and coordinated with the local control flow of the multi-channel signal source equipment to ensure accurate issuance of synchronization commands and strict alignment of multi-channel states.

[0039] During the software precision compensation stage, due to inherent phase differences in the local oscillators of each RF channel in the multi-channel signal source, amplitude and phase consistency differences in the RF link, and the possibility of slight propagation delay differences in the transmission cables despite their equal-length design, a fixed phase deviation still exists in each RF channel after hardware synchronization. To address this, the control unit reads pre-stored phase calibration data and performs reverse compensation for the fixed phase deviation of each RF channel in the initial phasor signal. Specifically, the phase control parameters of the orthogonal complex modulation unit in the baseband processing module can be configured to independently and precisely adjust the phase of the output signal of each channel. The phase adjustment range is continuously adjustable from 0° to 360° with a resolution better than 0.05°, and joint calibration is performed using power and time delay parameters. After reverse compensation, the inherent amplitude and phase consistency differences of each RF channel can be completely eliminated, ensuring that the compensated initial phasor signal reaches a reference state with a fixed initial phase at the output end, retaining only a very small range of random jitter differences, thus meeting the phase consistency requirements between multiple signals after power-on.

[0040] It should be noted that, Figure 3 The LO (Local Oscillator Distribution Signal) is the local oscillator distribution signal, which is uniformly fed to each signal generator by the local oscillator distribution module to ensure the phase consistency and frequency stability of the mixing link. The SYNC (Phase Synchronization Signal) is the phase synchronization signal, which is used to align the initial phase and output timing of each channel, and to establish a reference state with a fixed initial phase in conjunction with the coherent synchronization device.

[0041] S102. By switching the test path of the switching network, the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component are obtained respectively, and calibration end face correction parameters are generated to compensate for the amplitude and phase deviation of each excitation channel.

[0042] This step uses a dynamically switching test path to separate and collect the inherent amplitude and phase discrete values ​​of each excitation channel and the fixed phase offset of the directional coupling component on the physical link, and then fuses them to generate calibration end-face correction parameters that act on the physical interface of the antenna port. Figure 4 This is a schematic diagram illustrating the calibration path switching and error compensation principle provided by the present invention. The calibration process is based on the coordinated operation of the phase correction end face on the left (i.e., the port measurement of the vector network analyzer) and the calibration end face on the right (i.e., the port physical interface of the phased array antenna under test output by the switch network). The left end face is used for the acquisition and comparison measurement of the original calibration data, while the right end face is used for the final application of the compensation parameters and the excitation output reference. The two are precisely mapped through data translation logic.

[0043] Reference Figure 4 The calibration channel path is shown by the dashed line in the diagram. The control unit first controls the switch network to switch to the calibration channel path and performs basic parameter acquisition on the left phase correction end face. Specifically, the first RF channel of the multi-channel signal source is connected to the vector network analyzer as a reference channel. While maintaining physical connectivity with this reference channel, the control switch network sequentially switches the remaining RF channels to other receiving ports of the vector network analyzer. At this time, the vector network analyzer uses the signal of the first RF channel as the absolute reference and acquires the complex transmission response of the currently connected channel in real time on the left phase correction end face. For example, by analyzing the difference in magnitude and argument, it directly determines the amplitude deviation, phase deviation, and time delay deviation of each excitation channel relative to the reference channel and uses them as basic calibration parameters. The ports of the multi-channel signal source to the phased array antenna under test via the switch network and directional coupling components constitute each excitation channel. This end-to-end definition ensures that the reference measurement covers all physical nodes of the actual signal transmission.

[0044] Furthermore, at the time delay calibration execution level, if the current test signal is a continuous wave, the time delay deviation calibration can be equivalent to phase deviation calibration. If time delay calibration is required for multiple vector signals, a pulse triggering method can be used to trigger the simultaneous generation of multiple signals. This, combined with external measurement equipment, calibrates the time delay of each channel signal and synchronously incorporates the calibrated time delay data into the basic calibration parameters. This reference channel-based, one-to-one comparison measurement method, combined with the corresponding frequency routing compensation data pre-stored in the switching network, and calculated and fused by the control unit, can complete the amplitude, phase, and time delay consistency calibration of each excitation channel.

[0045] After completing the basic parameter acquisition, in order to accurately isolate the inherent deviations introduced by passive components at the end of the link, such as... Figure 4As shown, the system error of the directional coupling component is independently quantified on the same left-side phase correction end face. Specifically, the control unit directly connects the first RF channel to the vector network analyzer via a switching network to measure the first phase value. The control unit disconnects the direct connection of the first RF channel, switches the routing through the switching network, connects the second RF channel in series with the directional coupling component, and then connects it to the vector network analyzer. At this time, the signal must completely pass through the internal transmission network of the directional coupling component. The vector network analyzer collects the phase response after the directional coupling component is loaded on the same left-side phase correction end face and records it as the second phase value. The difference between the second phase value and the first phase value measured in the direct connection state is calculated. This difference reflects the fixed phase shift introduced by the structure of the directional coupling component itself and is directly quantified as the system error. This measurement logic of direct connection reference and series connection comparison can effectively separate the channel hardware discreteness and the inherent phase shift of the coupling device, ensuring the purity of subsequent compensation data. The second RF channel is any pre-specified RF channel in the multi-channel signal source other than the first RF channel.

[0046] Based on the fundamental calibration parameters and system errors independently obtained from the left phase correction end face, the control unit superimposes and calculates the results to generate the effect applied to... Figure 4 The calibration end face correction parameters are located on the right side of the calibration end face. In actual execution, frequency compensation data for different routing paths pre-stored within the switching network can be called to equivalently shift the measurement reference from the left phase correction end face to the right calibration end face. The calibration end face correction parameters generated after this reference plane transfer calculation can directly apply to the physical interface plane of the port from the switching network output to the phased array antenna under test, completely eliminating all fixed phase deviations introduced by routing differences within the switching network, transmission cable delays, and directional coupling components. This dual-end face collaborative calibration mechanism can ensure precise decoupling between the measurement plane and the compensation plane, enabling the compensated excitation signal to achieve strict amplitude and phase consistency at the calibration end face, providing an end-to-end high-precision signal reference for subsequent full-array synchronous excitation and active standing wave vector calculation.

[0047] S103. Based on the calibration end face correction parameters, control each RF channel to synchronously output excitation signals to the phased array antenna under test. Collect the incident and reflected signals extracted by the directional coupling components through a vector network analyzer. Solve the active standing wave test data of the phased array antenna under test according to the vector ratio of the incident and reflected signals.

[0048] This step transforms the amplitude and phase compensation reference generated during the calibration phase into a full-array synchronous excitation under actual operating conditions, and completes the vector acquisition and solution of active standing wave data. Figure 5 This is a schematic diagram of the signal excitation and standing wave acquisition path provided by the present invention, as shown below. Figure 5As shown, after generating the calibration end-face correction parameters, the control unit switches the switch network from the calibration channel path to the signal excitation channel path. In this state, the calibration end-face correction parameters are loaded and take effect. With the calibration end-face correction parameters in effect, the control unit drives each RF channel to synchronously output excitation signals with preset amplitude and phase distributions. This preset distribution is pre-set by the beam pointing or scanning angle state required for the test. After the multi-channel signals, after amplitude and phase compensation, achieve phase consistency at the calibration end-face, they are routed to the antenna port through the switch network, so that the excitation signal simultaneously acts on all array elements of the phased array antenna under test. This simultaneous excitation mechanism of the entire array can overcome the limitations of traditional static testing with single-port excitation and matching loads at the other ports, and physically excites the electromagnetic mutual coupling effect between array elements, enabling the antenna system to enter an active operating condition that is highly consistent with the actual transmit / receive operating state.

[0049] During signal transmission to the antenna port, directional coupling components (such as...) are connected in series at the ends of each excitation path. Figure 5 The dual directional bridge shown separates the forward and return waves in real time. The coupling port of the directional coupling component extracts the incident signal at the current port, and the isolation port extracts the reflected signal after reflection by the antenna array. Figure 5 The port connections shown are as follows: the coupling port and the isolation port are connected to port 1 and port 2 of the vector network analyzer via RF cables, respectively. The control unit configures the corresponding port of the vector network analyzer to receiver mode, so that it no longer transmits test signals, but instead synchronously acquires complex vector data containing amplitude and phase information of the incident and reflected signals.

[0050] Based on the acquired vector data, the control unit performs active standing wave (VSWR) calculation using the vector ratio of the incident and reflected signals. Specifically, the vector network analyzer synchronously acquires the incident and reflected signal vectors in receiver mode. The control unit first calculates the complex quotient of the reflected and incident signal vectors to obtain the active reflection coefficient of the antenna port under the current full-array excitation state. Then, the magnitude of the active reflection coefficient is substituted into the standard VSWR conversion formula to calculate the active voltage standing wave ratio (VSWR) of the port. By traversing or acquiring vector data from each antenna port in parallel, active VSWR test data for the phased array antenna under test covering the entire array is finally generated. This vector ratio calculation logic based on real mutual coupling conditions ensures that the test results accurately reflect the actual matching characteristics of the antenna under preset amplitude and phase distributions, providing high-fidelity data support for array performance evaluation and power tolerance analysis of transmitting components.

[0051] This invention provides an active standing wave (VSWR) test method for phased array antennas, applied to the control unit of a test system. The test system also includes a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. First, the coherent synchronization device synchronizes each RF channel of the multi-channel signal source to establish a reference state with a fixed initial phase. Then, by switching the test path of the switching network, the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component are obtained respectively, generating calibration end-face correction parameters to compensate for the amplitude and phase deviations of each excitation channel. Finally, the calibration end-face correction parameters control the synchronous output excitation signal of each RF channel to act on the phased array antenna under test. The incident and reflected signals extracted by the directional coupling component are acquired by the vector network analyzer, and the active VSWR test data of the phased array antenna under test is calculated based on the vector ratio of the incident and reflected signals. Therefore, this invention can achieve realistic simulation of simultaneous excitation of all array elements across the entire array surface, ensuring the determinism and repeatability of the relative phase of the output signals of each RF channel, and unifying the calibration endpoint to the physical interface of the antenna port to completely eliminate fixed phase deviations in the link. Furthermore, after the calibration endpoint correction parameters are generated once, multi-frequency or multi-scan state tests do not require repeated calibration, thereby significantly improving test accuracy and engineering efficiency.

[0052] Furthermore, the active standing wave (VSWR) testing method for phased array antennas provided by this invention also features a multi-state joint testing mode. For example, the control unit calls the generated calibration end-face correction parameters and keeps the amplitude compensation and time delay compensation values ​​in the calibration end-face correction parameters unchanged, independently configuring the phase compensation values ​​of each RF channel to simulate different scanning angles. Based on the beamforming principle of phased array antennas, the relative phase difference required for the corresponding target scanning angle is independently loaded for each RF channel through a linear phase gradient or nonlinear weighting algorithm. This phase compensation value is directly superimposed on the reference that has eliminated the inherent phase deviation of the link, driving each RF channel to output a new preset phase distribution. At this time, the multi-channel signal source synchronously outputs the excitation signal after amplitude and phase decoupling compensation, which acts on the entire array surface of the phased array antenna under test. Under the premise that the amplitude and time delay compensation parameters remain constant, the vector network analyzer or the matching far / near field test equipment synchronously collects the complex field strength distribution of the antenna radiation field, and calculates the antenna pattern test data under the current scanning angle through the beamforming algorithm.

[0053] It should be noted that since the amplitude attenuation and time delay deviation are mainly determined by the hardware link of the multi-channel signal source, the routing characteristics of the switching network, and the physical properties of the transmission cable, they are static inherent deviations that are independent of the beam scanning angle. Therefore, locking this part of the compensation value in different scanning states will continue to be effective, and there is no need for repeated calibration.

[0054] By sequentially traversing or switching the phase compensation values ​​of each RF channel, this invention can continuously simulate multiple beam pointing states and simultaneously complete multiple antenna pattern tests without interrupting the hardware link or repeating the calibration process. This completely decouples hardware link calibration, such as amplitude / delay calibration, from beam scanning control, avoiding the efficiency bottleneck of traditional methods where full-link amplitude and phase calibration must be performed every time the scanning angle is switched. Only one calibration is needed before testing, which can take into account both active standing wave and pattern joint testing, significantly improving the engineering efficiency and data consistency of phased array antenna full-condition performance evaluation.

[0055] In some embodiments, the active standing wave (VSWR) testing method for phased array antennas provided in this application also supports modular cascading of hardware channels to adapt to the testing requirements of large-scale phased array antennas. When the number of ports of the phased array antenna under test is greater than the number of RF channels configured in the current multi-channel signal source, the control unit controls the multi-channel signal source and the switching network to cascade and expand, so that the total number of channels in the expanded system matches the number of antenna ports.

[0056] After cascading expansion, the control unit can fully reuse the synchronization, calibration, and excitation test procedures described in the aforementioned embodiments in the expanded system architecture. Specifically, firstly, a common reference clock and synchronization trigger signal are synchronously distributed to all expanded RF channels to ensure that the new channels and the original channels establish an initial phase-fixed reference state under a unified timing framework. Subsequently, the calibration process of acquiring basic calibration parameters, quantifying the system error of directional coupling components, and generating calibration end-face correction parameters is sequentially executed on all expanded excitation channels to eliminate the amplitude, phase, and delay discreteness introduced by the expansion link. Finally, with the calibration end-face correction parameters in effect, the expanded full array is controlled to synchronously output excitation signals to complete the active standing wave test of the large-scale array.

[0057] This cascaded expansion mechanism requires no reconstruction of the underlying control algorithm or modification of the calibration logic. It can smoothly transition to test scenarios for 32-channel, 64-channel, or larger arrays simply by stacking hardware modules and configuring the number of channels. By reusing existing synchronous benchmarking, end-to-end error compensation, and full-array real-condition simulation processes, this invention can effectively overcome the physical bottleneck of the number of channels in a single test device, significantly improving the compatibility and engineering scalability of the test system at different stages of phased array antenna development and mass production.

[0058] Figure 6 This is a schematic diagram of the structure of the testing equipment provided by the present invention, as shown below. Figure 6As shown, the test device may include: a processor 610, a communication interface 620, a memory 630, and a communication bus 640, wherein the processor 610, the communication interface 620, and the memory 630 communicate with each other through the communication bus 640. The processor 610 can call logic instructions in the memory 630 to execute an active standing wave test method for a phased array antenna. This method is applied to the control unit of the test system, which also includes a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. The method includes: controlling the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with an initial fixed phase; acquiring the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component by switching the test path of the switching network, and generating calibration end-face correction parameters for compensating for the amplitude and phase deviation of each excitation channel; controlling each radio frequency channel to synchronously output excitation signals to the phased array antenna under test based on the calibration end-face correction parameters; acquiring the incident signal and reflected signal extracted by the directional coupling component through the vector network analyzer; and calculating the active standing wave test data of the phased array antenna under test based on the vector ratio of the incident signal and the reflected signal.

[0059] Furthermore, the logical instructions in the aforementioned memory 630 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0060] On the other hand, the present invention also provides a test system, characterized in that it includes: a control unit and a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer communicatively connected to the control unit. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. The control unit is configured to execute an active standing wave test method for the phased array antenna. The method includes: controlling the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with an initial fixed phase; acquiring the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component by switching the test path of the switching network, and generating calibration end-face correction parameters for compensating for the amplitude and phase deviation of each excitation channel; controlling each radio frequency channel to synchronously output excitation signals to the phased array antenna under test based on the calibration end-face correction parameters; acquiring the incident signal and reflected signal extracted by the directional coupling component through the vector network analyzer; and calculating the active standing wave test data of the phased array antenna under test based on the vector ratio of the incident signal and the reflected signal.

[0061] In another aspect, the present invention also provides a computer program product, which includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the active standing wave test method for phased array antennas provided by the above methods. This method is applied to the control unit of the test system, which also includes a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. The method includes: controlling the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with an initial fixed phase; obtaining the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component by switching the test path of the switching network, and generating calibration end face correction parameters for compensating for the amplitude and phase deviation of each excitation channel; controlling each radio frequency channel to synchronously output excitation signals to the phased array antenna under test based on the calibration end face correction parameters; collecting the incident signal and reflected signal extracted by the directional coupling component through the vector network analyzer; and calculating the active standing wave test data of the phased array antenna under test based on the vector ratio of the incident signal and the reflected signal.

[0062] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon. When executed by a processor, the computer program implements the active standing wave test method for phased array antennas provided by the above methods. This method is applied to the control unit of a test system, which also includes a coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer. A directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test. The method includes: controlling the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with an initial fixed phase; acquiring the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component by switching the test path of the switching network, and generating calibration end-face correction parameters for compensating for the amplitude and phase deviation of each excitation channel; controlling each radio frequency channel to synchronously output excitation signals to the phased array antenna under test based on the calibration end-face correction parameters; acquiring the incident signal and reflected signal extracted by the directional coupling component through the vector network analyzer; and calculating the active standing wave test data of the phased array antenna under test based on the vector ratio of the incident signal and the reflected signal.

[0063] The embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0064] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; 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; and these 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 testing active standing wave ratios of a phased array antenna, characterized in that, A control unit is applied to a test system, the test system further including a phase-coherent synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer, wherein a directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test; the method includes: The phase-coherent synchronization device is controlled to synchronize each radio frequency channel of the multi-channel signal source to establish a reference state with a fixed initial phase. By switching the test path of the switching network, the basic calibration parameters of each excitation channel and the system error introduced by the directional coupling component are obtained respectively. Based on the superposition of the basic calibration parameters and the system error, calibration end face correction parameters are generated to compensate for the amplitude and phase deviation of each excitation channel. The calibration end face is the physical interface surface of the port from the switch network output to the phased array antenna under test. Based on the calibration end face correction parameters, the excitation signals of each RF channel are synchronously output and applied to the phased array antenna under test. The incident and reflected signals extracted by the directional coupling component are collected by the vector network analyzer. The active standing wave test data of the phased array antenna under test are calculated based on the vector ratio of the incident signal and the reflected signal.

2. The method according to claim 1, characterized in that, The method of controlling the coherent synchronization device to synchronize each radio frequency channel of the multi-channel signal source to establish an initial phase-fixed reference state includes: The coherent synchronization device distributes a common reference clock and a synchronization trigger signal to the multi-channel signal source, so that each radio frequency channel outputs an initial coherent signal based on the common reference clock and at the edge of the synchronization trigger signal. Read the pre-stored phase calibration data and perform reverse compensation on the fixed phase deviation of each radio frequency channel in the initial phase coherent signal, so that the compensated initial phase coherent signal reaches the reference state with the initial phase fixed at the output end.

3. The method according to claim 1, characterized in that, By switching the test path of the switch network, the basic calibration parameters of each excitation channel are obtained, including: The first radio frequency channel of the multi-channel signal source is connected to the vector network analyzer via the switching network as a reference channel. With the reference channel remaining connected, the remaining radio frequency channels are sequentially connected to the vector network analyzer via the switch network. The amplitude, phase, and time delay deviations of each excitation channel are determined based on the reference channel and used as the basic calibration parameters. The multi-channel signal source, via the switching network and the directional coupling component, connects to the port of the phased array antenna under test, forming each excitation channel.

4. The method according to claim 3, characterized in that, By switching the test path of the switching network, the system error introduced by the directional coupling component is obtained, including: The first radio frequency channel is directly connected to the vector network analyzer through the switching network to measure the first phase value; Disconnect the first RF channel from the vector network analyzer, connect the second RF channel in series with the directional coupling component through the switch network to the vector network analyzer, and measure the second phase value. The second RF channel is any RF channel in the multi-channel signal source that is pre-specified other than the first RF channel. The difference between the second phase value and the first phase value is taken as the system error introduced by the directional coupling component.

5. The method according to any one of claims 1 to 4, characterized in that, The step of controlling the synchronous output excitation signal of each RF channel to act on the phased array antenna under test based on the calibration end face correction parameters includes: When the calibration end face correction parameters are in effect, the excitation signal with a preset amplitude and phase distribution is synchronously output by each radio frequency channel, and the excitation signal is simultaneously applied to all array elements of the phased array antenna under test.

6. The method according to claim 5, characterized in that, When the number of ports of the phased array antenna under test is greater than the number of radio frequency channels configured in the current multi-channel signal source, it also includes: The number of ports of the phased array antenna under test is matched by cascading the multi-channel signal source and the switching network. The reference clock and trigger signal are synchronously distributed to all expanded RF channels, and amplitude and phase calibration and error compensation are performed on all expanded excitation channels. The expanded full array is controlled to synchronously output the excitation signal.

7. The method according to claim 1, characterized in that, After generating the calibration end face correction parameters, the process also includes: Keeping the amplitude compensation value and time delay compensation value in the calibration end face correction parameters unchanged, independently configure the phase compensation value of each RF channel to simulate different scanning angles, and synchronously perform antenna pattern testing.

8. A testing system, characterized in that, include: The control unit, along with a phased-coordinate synchronization device, a multi-channel signal source, a switching network, and a vector network analyzer communicatively connected to the control unit, wherein a directional coupling component is connected in series on the excitation path between the switching network and the phased array antenna under test, and the control unit is configured to perform the active standing wave test method for phased array antennas as described in any one of claims 1 to 7.

9. A testing device, characterized in that, The method includes a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that the processor executes the computer program to implement the active standing wave test method for a phased array antenna as described in any one of claims 1 to 7.

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