Frequency domain response test method, system and electronic device

Abstract

This invention discloses a frequency domain response testing method, system, and electronic device. The method includes: receiving a test execution command sent by a master control terminal; transmitting a first radio frequency (RF) signal and a first local oscillator (LO) signal in response to the test execution command; receiving a reference mixing signal, an auxiliary LO signal, and a feedback mixing signal; and feeding back the reference mixing signal, the auxiliary LO signal, and the feedback mixing signal to the master control terminal, so that the master control terminal can determine the frequency domain response test result based on the reference mixing signal, the auxiliary LO signal, and the feedback mixing signal. This invention solves the technical problem of inaccurate frequency domain response testing in related technologies when performing frequency domain response testing on RF systems.

Description

Technical Field

[0001] This invention relates to the field of wireless communication, and more specifically, to a frequency domain response testing method, system, and electronic device. Background Technology

[0002] In related technologies, frequency domain response testing is a test for objects under test, such as antennas and arrays, anechoic chamber system calibration, and radio frequency devices and channel responses, in order to achieve a quantitative assessment of the transmission performance, spatial radiation characteristics, and system distortion of the objects under test. However, in related technologies, there is a technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on objects under test.

[0003] There is currently no effective solution to the above problems. Summary of the Invention

[0004] This invention provides a frequency domain response testing method, system, and electronic device to at least solve the technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on radio frequency systems in related technologies.

[0005] According to one aspect of the present invention, a frequency domain response testing method is provided, comprising: receiving a test execution command sent by a master control terminal; transmitting a first radio frequency signal and a first local oscillator signal in response to the test execution command; receiving a reference mixing signal, an auxiliary local oscillator signal, and a feedback mixing signal, and feeding back the reference mixing signal, the auxiliary local oscillator signal, and the feedback mixing signal to the master control terminal, so that the master control terminal determines a frequency domain response test result based on the reference mixing signal, the auxiliary local oscillator signal, and the feedback mixing signal, wherein the reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal, and the auxiliary local oscillator signal is determined based on the backward local oscillator signal along the signal feedback direction. The transmitted signal is obtained by transmitting the return mixing signal along the signal return direction based on the test mixing signal. The test mixing signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is obtained by transmitting the first radio frequency signal after frequency multiplication, which is emitted by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point, along the transmission direction. The first radio frequency signal after frequency multiplication is the radio frequency signal after frequency multiplication of the first radio frequency signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by signal splitting of the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

[0006] Optionally, the second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction through the forward test link, and the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction through the backward test link; wherein, the forward test link includes: a first electro-optical module, a first circulator, a second circulator, a power divider, a first optical-to-electrical module, and a first optical fiber, and the power divider is connected between the first electro-optical module and the first optical-to-electrical module through the first optical fiber; the backward test link includes: a first circulator, a second optical fiber, and a second optical-to-electrical module, the first circulator is connected between the first electro-optical module and the power divider through the first optical fiber, the second circulator is connected between the first circulator and the power divider through the first optical fiber, and the first circulator is connected to the second optical-to-electrical module through the second optical fiber.

[0007] Optionally, the first optical fiber and the second optical fiber are the same type of optical fiber.

[0008] Optionally, the return mixing signal is obtained by transmitting the test mixing signal along the signal return direction through the return test link; wherein, the return test link includes: a third electro-optical module, a third optical fiber and a third optical-electrical module, and the third electro-optical module is connected to the third optical-electrical module through the third optical fiber.

[0009] Optionally, the reference mixing signal is obtained by performing a first signal processing on the first radio frequency signal and the first local oscillator signal through an upconverter, wherein the upconverter is deployed at a first location, and the spatial distance between the first location and the terminal location of the main control terminal is less than a first distance threshold. The first signal processing includes: performing frequency multiplication on the first radio frequency signal to obtain a frequency-multiplied first radio frequency signal; performing frequency multiplication on the first local oscillator signal to obtain a frequency-multiplied first local oscillator signal; and performing frequency mixing on the frequency-multiplied first radio frequency signal and the frequency-multiplied first local oscillator signal to obtain the reference mixing signal.

[0010] Optionally, the test mixed signal is obtained by performing a second signal processing on the second radio frequency signal and the second local oscillator signal through a downconverter, wherein the downconverter is deployed at a second location, and the spatial distance between the second location and the terminal location of the main control terminal is greater than a second distance threshold. The second signal processing includes: performing frequency multiplication on the second local oscillator signal to obtain a frequency-multiplied second local oscillator signal; and performing frequency mixing processing on the frequency-multiplied second local oscillator signal and the second radio frequency signal to obtain the test mixed signal.

[0011] According to one aspect of the present invention, a frequency domain response testing method is provided, comprising: receiving a response test request sent by a user terminal, wherein the response test request carries a frequency domain response test task; in response to the response test request, determining a sampling point sequence corresponding to the frequency domain response test task; controlling a transmitting antenna on a three-dimensional scanning gantry to reach a corresponding sampling point according to the execution order of each sampling point in the sampling point sequence, and sending a test execution command to a vector network analyzer; receiving a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal fed back by the vector network analyzer, wherein the reference mixing signal is determined based on a first radio frequency signal and a first local oscillator signal transmitted by the vector network analyzer, the auxiliary local oscillator signal is obtained based on the backward local oscillator signal transmitted along the signal return direction, and the return mixing signal is obtained based on the test mixing signal transmitted along the signal return direction. The test mixing signal is determined based on a second radio frequency (RF) signal and a second local oscillator (LO) signal. The second RF signal is obtained by transmitting a frequency-doubled first RF signal transmitted by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point along the transmission direction. The frequency-doubled first RF signal is the RF signal obtained by frequency-doubled processing of the first RF signal. The second LO signal is obtained by transmitting a forward LO signal along the signal transmission direction. The forward LO signal and the backward LO signal are obtained by signal splitting of the first LO signal. The forward LO signal and the backward LO signal have the same frequency and phase. Based on the auxiliary LO signal, the return mixing signal is corrected to obtain a corrected mixing signal. Based on the corrected mixing signal and the reference mixing signal, the test result of the corresponding sampling point is determined until all sampling points are completed, and the frequency domain response test result is obtained.

[0012] According to one aspect of the present invention, a frequency domain response testing method is provided, comprising: after controlling a three-dimensional scanning rig to reach a corresponding sampling point via a master control terminal, receiving and transmitting a frequency-doubled first radio frequency signal, so that the frequency-doubled first radio frequency signal is transmitted along the signal transmission direction to obtain a second radio frequency signal; determining a test mixing signal based on the second radio frequency signal and a second local oscillator signal; obtaining a return mixing signal based on the test mixing signal transmitted along the signal return direction; and receiving the return mixing signal, a reference mixing signal, and an auxiliary local oscillator signal by the master control terminal, and determining the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal based on the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal. The frequency domain response test results are determined, wherein the first radio frequency signal after frequency doubling is obtained by frequency doubling the first radio frequency signal emitted by the vector network analyzer, the second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction, the reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal emitted by the vector network analyzer, the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction, the forward local oscillator signal and the backward local oscillator signal are obtained by signal splitting the first local oscillator signal, and the forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

[0013] According to one aspect of the present invention, a frequency domain response testing system is provided, comprising: a vector network analyzer, configured to receive a test execution command sent by a master control terminal; in response to the test execution command, transmit a first radio frequency signal and a first local oscillator signal; receive a reference mixing signal, an auxiliary local oscillator signal and a return mixing signal, and feed back the reference mixing signal, the auxiliary local oscillator signal and the return mixing signal to the master control terminal; the master control terminal, configured to receive a response test request sent by a user terminal, wherein the response test request carries a frequency domain response test task; in response to the response test request, determine a sampling point sequence corresponding to the frequency domain response test task; and perform sampling point testing according to the sampling point sequence. The execution order of each sampling point in the column controls the transmitting antenna on the 3D scanning rig to reach the corresponding sampling point and sends a test execution command to the vector network analyzer; it receives the reference mixing signal, auxiliary local oscillator signal and return mixing signal fed back by the vector network analyzer; based on the auxiliary local oscillator signal, the return mixing signal is corrected to obtain a corrected mixing signal; based on the corrected mixing signal and the reference mixing signal, the test result of the corresponding sampling point is determined until each sampling point is completed, and the frequency domain response test result is obtained; the transmitting antenna on the 3D scanning rig is used to receive and transmit the first radio frequency signal after frequency doubling after the 3D scanning rig reaches the corresponding sampling point through the main control terminal.

[0014] According to one aspect of the present invention, an electronic device is provided, comprising: a processor; a memory for storing processor-executable instructions; wherein the processor is configured to execute the instructions to implement the frequency domain response testing method described in any of the preceding embodiments.

[0015] According to one aspect of the present invention, a computer-readable storage medium is provided, wherein when the instructions in the computer-readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to perform the frequency domain response test method described above.

[0016] According to one aspect of the present invention, a computer program product is provided, comprising a computer program that, when executed by a processor, implements the steps of the frequency domain response testing method described in any of the preceding claims.

[0017] In this embodiment of the invention, a test execution command sent by a master control terminal is received, and a first radio frequency signal and a first local oscillator signal are transmitted in response to the test execution command. Then, a reference mixing signal, an auxiliary local oscillator signal, and a feedback mixing signal are received, and these signals are fed back to the master control terminal. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal; the auxiliary local oscillator signal is obtained by transmitting the back-to-back local oscillator signal along the signal feedback direction; the feedback mixing signal is obtained by transmitting the test mixing signal along the signal feedback direction; and the test mixing signal is determined based on a second radio frequency signal and a second local oscillator signal. The second radio frequency signal is a frequency-multiplied first radio frequency signal transmitted after the transmitting antenna on the three-dimensional scanning gantry reaches the corresponding sampling point. The signal is transmitted along the transmission direction. The first radio frequency signal after frequency doubling is the radio frequency signal after frequency doubling of the first radio frequency signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by splitting the first local oscillator signal and have the same frequency and phase. This allows the main control terminal to simultaneously obtain the original mixing reference, the link transmission error characterization signal and the actual mixing signal after spatial transmission. The auxiliary local oscillator signal with the same source split and the same phase is used to compensate for the link phase drift and amplitude attenuation in the return mixing signal, thereby eliminating the error introduced by long-distance transmission and frequency doubling. This solves the technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on radio frequency systems in related technologies. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0019] Figure 1This is a flowchart of a frequency domain response testing method according to an embodiment of the present invention;

[0020] Figure 2 This is a flowchart of a second frequency domain response testing method according to an embodiment of the present invention;

[0021] Figure 3 This is a flowchart of frequency domain response testing method three according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the frequency domain response test framework in an optional embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the frequency domain response testing method in an optional embodiment of the present invention;

[0024] Figure 6 This is a schematic diagram of the phase drift of the forward test link in an optional embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of phase drift of the backward test link in an optional embodiment of the present invention;

[0026] Figure 8 This is a schematic diagram of the link phase result after phase compensation in an optional embodiment of the present invention;

[0027] Figure 9 This is a schematic diagram of the phase distribution of the main array elements in an optional embodiment of the present invention;

[0028] Figure 10 This is a schematic diagram of the angle-delay-power spectrum distribution obtained by measuring a uniform circular array in an optional embodiment of the present invention;

[0029] Figure 11 This is a schematic diagram of the angle-delay-power spectrum after array signal processing in an optional embodiment of the present invention;

[0030] Figure 12 This is a structural block diagram of a frequency domain response testing system according to an embodiment of the present invention. Detailed Implementation

[0031] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0033] Example 1

[0034] According to an embodiment of the present invention, an embodiment of a frequency domain response testing method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0035] Figure 1 This is a flowchart of a frequency domain response testing method according to an embodiment of the present invention, as shown below. Figure 1 As shown, the method includes the following steps:

[0036] S102, receives the test execution command sent by the main control terminal;

[0037] This involves a master control terminal, a control device used to send test execution commands and control the frequency domain response test process. It can issue commands to test instruments such as vector network analyzers, receive feedback data, and perform data analysis. Specifically, the memory in the master control terminal includes random access memory or non-volatile memory, with non-volatile memory including, but not limited to, at least one disk storage device. The processor in the master control terminal is a general-purpose processor or a special-purpose processor, including, but not limited to, a central processing unit (CPU), a network processor, as well as digital signal processors, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components.

[0038] This involves test execution commands, which are control commands sent by the main control terminal to the vector network analyzer to trigger frequency domain response testing. These commands may include frequency sweep start commands, parameter configuration commands, trigger acquisition commands, etc., to trigger the vector network analyzer to start transmitting and receiving corresponding signals according to preset parameters.

[0039] By receiving test execution commands sent by the main control terminal, the vector network analyzer can start the frequency domain response test process under the unified control timing of the main control terminal, ensuring that the subsequent actions of transmitting the first radio frequency signal and the first local oscillator signal are executed in an orderly manner according to the preset parameters.

[0040] S104, in response to the test execution command, transmits a first radio frequency signal and a first local oscillator signal;

[0041] This involves a first radio frequency (RF) signal, which is a fundamental RF excitation signal emitted by the vector network analyzer in response to a test execution command for frequency domain response testing. Specifically, the frequency range of this first RF signal is any set frequency point or sweep sequence within the operating frequency band of the vector network analyzer, which is subsequently multiplied by a frequency and used as a carrier signal for spatial radiation.

[0042] This involves a first local oscillator signal, which is a local oscillator reference signal for frequency conversion emitted by the vector network analyzer in response to a test execution command. It can be used to provide a stable frequency and phase reference.

[0043] The system responds to test execution commands and transmits the first radio frequency signal and the first local oscillator signal, which can establish an accurate excitation source and a stable local oscillator reference for subsequent frequency domain response tests.

[0044] S106: Receive a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal, and feed these signals back to the main control terminal. This allows the main control terminal to determine the frequency domain response test result based on the reference mixing signal, auxiliary local oscillator signal, and return mixing signal. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal. The auxiliary local oscillator signal is obtained by transmitting the signal back along the signal return direction based on the forward local oscillator signal. The return mixing signal is obtained by transmitting the test mixing signal along the signal return direction. The signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is obtained by transmitting the first radio frequency signal after frequency multiplication, which is transmitted along the transmission direction after the transmitting antenna on the three-dimensional scanning frame reaches the corresponding sampling point. The first radio frequency signal after frequency multiplication is the radio frequency signal after frequency multiplication of the first radio frequency signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by decomposing the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

[0045] This involves a reference mixing signal, which is a mixing output signal determined based on the first radio frequency signal and the first local oscillator signal. For example, the reference mixing signal is generated by frequency multiplication and mixing of the first radio frequency signal and the first local oscillator signal. Its main function is to provide the main control terminal with the original reference signal that has not been transmitted in space, which is used to compare with the returned mixing signal to eliminate system errors.

[0046] This involves an auxiliary local oscillator signal, which is a local oscillator reference signal obtained by transmitting the backward local oscillator signal along the signal return direction. It provides the main control terminal with an error reference for link transmission phase drift and amplitude attenuation.

[0047] This involves a return mixing signal, which is a mixing output signal obtained by transmitting the test mixing signal along the signal return direction. It carries the actual measurement data after spatial transmission and mixing processing.

[0048] This involves a test mixing signal, which is a mixing output signal determined based on the second radio frequency signal and the second local oscillator signal. For example, the test mixing signal is generated by the mixing process of the second radio frequency signal and the second local oscillator signal through a downconverter. Its main function is to downconvert the high-frequency radio frequency signal after spatial transmission to the intermediate frequency range that can be transmitted back.

[0049] This involves a second radio frequency signal, which is the radio frequency signal obtained by transmitting the first radio frequency signal (which is frequency-doubled and transmitted at the corresponding sampling point through the transmitting antenna on the three-dimensional scanning frame) along the transmission direction, and carries the amplitude attenuation and phase shift data introduced by spatial transmission.

[0050] This involves a first radio frequency signal after frequency multiplication. This first radio frequency signal after frequency multiplication is a radio frequency signal after frequency multiplication of the first radio frequency signal (e.g., the frequency of the output signal after frequency multiplication is an integer multiple of the input signal frequency). For example, this first radio frequency signal after frequency multiplication is obtained by processing the first radio frequency signal through the frequency multiplication module of the upconverter, so as to boost the basic radio frequency excitation to the target test frequency band and meet the frequency requirements of high-frequency testing and transmission.

[0051] This involves a second local oscillator signal, which is a local oscillator reference signal obtained by transmitting the forward local oscillator signal along the signal transmission direction, and is used to provide a frequency conversion reference from the same source.

[0052] This involves a forward local oscillator signal, which is a local oscillator signal that is obtained by splitting the first local oscillator signal and is transmitted along the signal transmission direction.

[0053] This involves a backward local oscillator signal, which is obtained by splitting the first local oscillator signal and transmitting another local oscillator signal along the signal return direction. The forward and backward local oscillator signals maintain consistent frequency and phase characteristics during the splitting process. For example, the first local oscillator signal is split using the equal-division characteristic of a power divider to obtain the forward and backward local oscillator signals. This ensures that the two local oscillator signals have identical references before transmission, thus accurately characterizing the phase difference introduced by the link in subsequent comparisons.

[0054] This involves a 3D scanning frame, which is a device used for moving and positioning in three-dimensional space, and is used to carry a transmitting antenna to reach a designated sampling point.

[0055] This involves a transmitting antenna, which is an antenna on a three-dimensional scanning rig used to transmit (specifically, to radiate) the first radio frequency signal after frequency doubling.

[0056] By receiving the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal and feeding them back to the main control terminal, the main control terminal simultaneously obtains three sets of related signals: the original reference, the link error characterization, and the spatial transmission result. This is because the reference mixing signal is directly determined based on the original transmitted first radio frequency signal and the first local oscillator signal; the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal after splitting it from the same source along the signal return direction; and the return mixing signal is obtained by sequentially transmitting the first radio frequency signal after frequency doubling and mixing it with the second local oscillator signal obtained by transmitting the forward local oscillator signal from the same source before returning.

[0057] Through the above steps S102-S106, the system receives a test execution command sent by the main control terminal, transmits a first radio frequency signal and a first local oscillator signal in response to the test execution command, and then receives a reference mixing signal, an auxiliary local oscillator signal, and a feedback mixing signal. The reference mixing signal, auxiliary local oscillator signal, and feedback mixing signal are then fed back to the main control terminal. Specifically, the reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal; the auxiliary local oscillator signal is obtained by transmitting the back-to-back local oscillator signal along the signal feedback direction; the feedback mixing signal is obtained by transmitting the test mixing signal along the signal feedback direction; and the test mixing signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is the first local oscillator signal after being frequency-multiplied and transmitted by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point. The radio frequency (RF) signal is transmitted along the transmission direction. The first RF signal after frequency doubling is the RF signal obtained by frequency doubling the first RF signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by splitting the first local oscillator signal and have the same frequency and phase. This allows the main control terminal to simultaneously obtain the original mixing reference, the link transmission error characterization signal, and the actual mixing signal after spatial transmission. The auxiliary local oscillator signal with the same source split and the same phase is used to compensate for the link phase drift and amplitude attenuation in the return mixing signal, thereby eliminating the errors introduced by long-distance transmission and frequency doubling. This solves the technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on RF systems in related technologies.

[0058] As an optional embodiment, the second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction through the forward test link, and the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction through the backward test link. The forward test link includes: a first electro-optical module, a first circulator, a second circulator, a power divider, a first optical-to-electrical module, and a first optical fiber. The power divider is connected between the first electro-optical module and the first optical-to-electrical module via the first optical fiber. The backward test link includes: a first circulator, a second optical fiber, and a second optical-to-electrical module. The first circulator is connected between the first electro-optical module and the power divider via the first optical fiber, and the second circulator is connected between the first circulator and the power divider via the first optical fiber. The first circulator is also connected to the second optical-to-electrical module via the second optical fiber.

[0059] This involves a forward test link, which is a path for transmitting the forward local oscillator signal from a local end (where the spatial distance to the main control terminal / vector network analyzer is less than or equal to a predetermined spatial distance threshold) to a remote end (where the spatial distance to the main control terminal / vector network analyzer is greater than the predetermined spatial distance threshold). This forward test link includes a first electro-optical module, a first circulator, a second circulator, a power divider, a first optical-to-electrical module, and a first optical fiber to achieve long-distance transmission of the forward local oscillator signal. The signal transmission direction is from the local end to the remote end. The signal return direction is from the remote end to the local end. The spatial distance between the local end and the remote end is greater than the predetermined distance threshold to meet the far-field test conditions.

[0060] Among them, a first electro-optical conversion module is involved. The first electro-optical conversion module is a device that converts electrical signals into optical signals. It is used to convert a first local oscillator signal into a local oscillator optical signal for low-loss transmission in optical fiber.

[0061] This involves a first optical-to-electrical module, which is a device that converts optical signals into electrical signals.

[0062] This involves a first optical fiber, which is a medium for transmitting optical signals and its main function is to transmit signals over long distances in a low-loss and low-interference manner.

[0063] This involves a power divider, which is a passive device that splits an input signal into multiple (specifically two or more) outputs, such as splitting the local oscillator signal equally and ensuring that the frequencies and phases of the two signals (forward local oscillator signal and backward local oscillator signal) obtained after splitting are the same.

[0064] This involves a backward test link, which is a path used to transmit the backward local oscillator signal from a remote end to a local end. The backward test link includes: a first circulator, a second optical fiber, and a second optical-to-electrical converter module, used to transmit the backward local oscillator signal back to characterize the phase drift and amplitude attenuation introduced by the link transmission.

[0065] This involves a second optical fiber, which is a medium for transmitting backward local oscillator optical signals and is used to transmit the backward local oscillator optical signals separated by the first circulator to the second optical-to-electrical module.

[0066] This involves a second optical-to-electrical converter module, which is a device that converts optical signals into electrical signals. It is used to restore the backward local oscillator optical signal transmitted through the second optical fiber into an electrical signal, which is then fed back to the main control terminal as an auxiliary local oscillator signal for link error compensation. This second optical-to-electrical converter module can be the same as the first optical-to-electrical converter module.

[0067] This involves a first circulator, which is a non-reciprocal multi-port passive device, to enable the corresponding signal to be transmitted along a specified unidirectional path.

[0068] This involves a second circulator, which is a non-reciprocal multi-port passive device designed to transmit the corresponding signal along a specified unidirectional path. Similar to the first circulator, it is used to transmit the backward local oscillator signal output from the power divider back while isolating the forward transmission signal. This second circulator can be the same as the first circulator.

[0069] Taking a first circulator with three ports (first port, second port, and third port) and a second circulator with three ports (fourth port, fifth port, and sixth port) as an example, in the scenario where the unidirectional transmission of the first circulator includes unidirectional transmission from the first port to the second port and unidirectional transmission from the second port to the third port, and the unidirectional transmission of the second circulator includes unidirectional transmission from the fourth port to the fifth port and unidirectional transmission from the sixth port to the fourth port: the first port of the first circulator is connected to the first electro-optical module, the second port of the first circulator is connected to the fourth port of the second circulator, and the third port of the first circulator is connected to the second optical-to-electrical module; the fifth port of the second circulator is connected to the input of the power divider, the sixth port of the second circulator is connected to the second output of the power divider (used to output the backward local oscillator signal), and the first output of the power divider (used to output the forward local oscillator signal) is connected to the first optical-to-electrical module, thereby achieving isolation of bidirectional signals in the shared optical fiber path and avoiding crosstalk between bidirectional signals.

[0070] Specifically, the first local oscillator signal is electro-optically converted by the first electro-optical module to obtain a local oscillator optical signal; the local oscillator optical signal is transmitted to a power divider through the first optical fiber, and the power divider divides the transmitted local oscillator optical signal into a forward local oscillator signal and a backward local oscillator signal; the forward local oscillator signal is transmitted to the first optical-to-electrical module through the first optical fiber, and the transmitted forward local oscillator signal is photoelectrically converted by the first optical-to-electrical module to obtain a second local oscillator signal.

[0071] Furthermore, the signal flow direction of the local oscillator optical signal in the first circulator is as follows: it is transmitted from the first port to the second port, and after being transmitted through the first optical fiber, it reaches the second circulator. In the second circulator, the signal flow direction is transmitted from the fourth port to the fifth port. After reaching the power divider, the power divider divides the transmitted local oscillator optical signal into a forward local oscillator signal and a backward local oscillator signal. The forward local oscillator signal is output from the first output terminal of the power divider and transmitted through the first optical fiber to the first optical-to-electrical module. The backward local oscillator signal is output from the second output terminal of the power divider to the sixth port of the second circulator and then transmitted from the sixth port to the fourth port to realize the backhaul of the backward local oscillator signal.

[0072] The first local oscillator signal is electro-optically converted from an electrical signal to an optical signal by a first electro-optical module. This optical signal is then transmitted via the first optical fiber, leveraging the low loss and electromagnetic interference resistance of the fiber to achieve long-distance signal transmission. This avoids signal distortion caused by attenuation and interference in long-distance cable transmission. Furthermore, the power divider splits the first local oscillator signal into a forward local oscillator signal and a backward local oscillator signal, ensuring that the two signals have identical frequency and phase before transmission. Simultaneously, the non-reciprocal characteristics of the first and second circulators isolate the forward and backward transmission paths, ensuring that the local oscillator signal / forward local oscillator signal and the backward local oscillator signal do not interfere with each other during bidirectional transmission in the first optical fiber and experience the same fiber phase disturbance. This allows the auxiliary local oscillator signal to accurately characterize the phase drift and amplitude attenuation introduced by the forward test link, providing a precise reference for subsequent link error compensation of the return mixing signal and solving the technical problem of phase inconsistency caused by long-distance optical fiber transmission.

[0073] As an optional embodiment, the first optical fiber and the second optical fiber are the same type of optical fiber.

[0074] Since the first and second optical fibers are the same type of fiber, and both have the same refractive index, dispersion characteristics, and temperature response coefficient, the forward local oscillator signal undergoes the same phase change and attenuation characteristics per unit length when it is transmitted in the first fiber and the backward local oscillator signal is transmitted in the second fiber. Therefore, the auxiliary local oscillator signal can more accurately characterize the phase drift and amplitude attenuation introduced by the forward test link, thereby improving the accuracy of link error compensation and solving the technical problem of inconsistent bidirectional transmission characteristics caused by differences in fiber materials.

[0075] As an optional embodiment, the return mixing signal is obtained by transmitting the test mixing signal along the signal return direction through the return test link; wherein, the return test link includes: a third electro-optical module, a third optical fiber and a third optical-to-electrical module, and the third electro-optical module is connected to the third optical-to-electrical module through the third optical fiber.

[0076] This involves a backhaul test link, which is a path for transmitting the test mixed signal from the remote end to the local end. The backhaul test link includes a third electro-optical module, a third optical fiber, and a third optical-to-electrical module, which are used to convert the test mixed signal into an optical signal and then transmit it back via the optical fiber with low loss, and restore it to an electrical signal at the local end as the backhaul mixed signal.

[0077] This involves a third electro-optical conversion module, which is a device that converts electrical signals into optical signals. This module is used to convert the test mixing signal into an optical signal for low-loss transmission in a third optical fiber. This third electro-optical conversion module can be the same as the first electro-optical conversion module.

[0078] This involves a third optical fiber, which serves as the medium for transmitting optical signals. This third optical fiber is used to transmit the optical signal corresponding to the test mixing signal over long distances with low loss and low interference. The first, second, and third optical fibers can be the same type of optical fiber.

[0079] This involves a third optical-to-electrical converter module, which is a device that converts optical signals into electrical signals. It is used to restore the optical signals transmitted through the third optical fiber to electrical signals, which are then used as a return mixing signal for subsequent processing. This third optical-to-electrical converter module can be the same as the first optical-to-electrical converter module and / or the second optical-to-electrical converter module.

[0080] Specifically, the third electro-optical module converts the test mixed signal into an optical signal, which is then recorded as the test optical signal. This optical signal is then transmitted back to the third optical-to-electrical module via the third optical fiber. The third optical-to-electrical module converts the transmitted test optical signal into an electrical signal to obtain the return mixed signal, which is then transmitted back to the vector network analyzer.

[0081] Since the return mixed signal is obtained by transmitting the test mixed signal along the signal return direction through the return test link, and the return test link uses a third electro-optical module to convert the test mixed signal into an optical signal, which is then transmitted through a third optical fiber and then restored to an electrical signal by a third optical-to-electrical module, the low loss and anti-electromagnetic interference characteristics of optical fiber can be used to achieve long-distance low-distortion return of the test mixed signal. This avoids signal distortion caused by attenuation and interference in long-distance cable transmission of electrical signals, thereby ensuring that the return mixed signal received by the main control terminal accurately carries the actual measurement information after spatial transmission, and solving the technical problem of signal distortion during long-distance return.

[0082] As an optional embodiment, the reference mixing signal is obtained by performing a first signal processing on a first radio frequency signal and a first local oscillator signal through an upconverter. The upconverter is deployed at a first location, and the spatial distance between the first location and the terminal location of the main control terminal is less than a first distance threshold. The first signal processing includes: performing frequency multiplication on the first radio frequency signal to obtain a frequency-multiplied first radio frequency signal; performing frequency multiplication on the first local oscillator signal to obtain a frequency-multiplied first local oscillator signal; and performing frequency mixing on the frequency-multiplied first radio frequency signal and the frequency-multiplied first local oscillator signal to obtain a reference mixing signal.

[0083] This involves an up-converter, a device for performing a first signal processing on the input signal. This first signal processing includes frequency multiplication and mixing (to boost the fundamental frequency signal to the target test frequency band and generate a mixed signal). The up-converter is deployed at a first location (i.e., the location corresponding to the local terminal), and the spatial distance between this first location and the terminal location of the main control terminal is less than a first distance threshold. This allows the up-converter to be close to the main control terminal and / or the vector network analyzer, facilitating connection via short cables and reducing transmission loss and interference.

[0084] For example, the upconverter includes a first frequency multiplier module and a first frequency mixer module. The first frequency multiplier module is used to multiply the frequency of a first radio frequency signal to obtain a frequency-multiplied first radio frequency signal, and to multiply the frequency of a first local oscillator signal to obtain a frequency-multiplied first local oscillator signal; the first frequency mixer module is used to mix the frequency-multiplied first radio frequency signal and the frequency-multiplied first local oscillator signal to obtain a reference mixed signal.

[0085] After the transmitting antenna on the 3D scanning rig reaches the corresponding sampling point, the vector network analyzer transmits the first radio frequency signal and the first local oscillator signal. The first radio frequency signal and the first local oscillator signal are processed by the upconverter, so that the vector network analyzer has configurable expansion capability for different target test frequency bands.

[0086] This involves frequency multiplication, which is an operation that multiplies the frequency of the input signal by an integer multiple. For example, the first radio frequency signal and the first local oscillator signal are boosted to the target test frequency band to meet the high-frequency test requirements, thereby achieving flexible coverage of the target test frequency band in different application scenarios.

[0087] This involves frequency mixing, which is the operation of mixing two signals (which can be signals of different frequencies).

[0088] Since the upconverter is deployed at the first location and the spatial distance between this location and the main control terminal is less than the first distance threshold, the upconverter is close to the vector network analyzer. This allows for a short cable connection to reduce transmission loss and interference. Simultaneously, by performing frequency multiplication on the first RF signal and the first local oscillator signal respectively, the fundamental frequency is raised to the target test frequency band, enabling the vector network analyzer to have cross-frequency band testing capabilities and meet high-frequency testing requirements. Then, the two frequency-multiplied signals are mixed (specifically, a stable intermediate frequency signal with a frequency difference between the two signals is generated) to obtain a reference mixed signal. Therefore, the original mixed reference signal that has not undergone long-distance spatial transmission can be obtained near the signal source side (i.e., the local end), avoiding the influence of phase drift and amplitude attenuation introduced by subsequent link transmission on the reference signal, thereby providing an accurate reference for the main control terminal.

[0089] As an optional embodiment, the test mixed signal is obtained by performing a second signal processing on the second radio frequency signal and the second local oscillator signal through a downconverter. The downconverter is deployed at a second location, and the spatial distance between the second location and the terminal location of the main control terminal is greater than a second distance threshold. The second signal processing includes: performing frequency multiplication on the second local oscillator signal to obtain a frequency-multiplied second local oscillator signal; and performing frequency mixing processing on the frequency-multiplied second local oscillator signal and the second radio frequency signal to obtain the test mixed signal.

[0090] This involves a downconverter, a device for performing a second signal processing on the input signal. This second signal processing includes frequency multiplication and mixing (to boost the fundamental frequency signal to the target test frequency band and generate a mixed signal). The downconverter is deployed at a second location (i.e., a remote location), and the spatial distance between this second location and the terminal location of the main control terminal is greater than a second distance threshold. This allows the downconverter to be close to the receiving antenna deployed at the remote end, facilitating remote processing of the spatially transmitted signal.

[0091] For example, the downconverter includes a second frequency multiplier module and a second frequency mixer module. The second frequency multiplier module is used to multiply the frequency of the second local oscillator signal to obtain a frequency-multiplied second local oscillator signal. The second frequency mixer module is used to mix the frequency-multiplied second local oscillator signal and the second radio frequency signal to obtain a test mixed signal.

[0092] Because the downconverter is deployed at the second location and the spatial distance between this location and the main control terminal is greater than the second distance threshold, the downconverter is close to the remote receiving antenna. This allows the downconverter to directly process the second radio frequency signal after spatial transmission at the remote end. At the same time, the second local oscillator signal is frequency-multiplied to obtain a frequency-multiplied second local oscillator signal. This frequency-multiplied second local oscillator signal is then mixed with the second radio frequency signal to obtain a test mixed signal. This downconverts the high-frequency spatial transmission signal to the intermediate frequency range, which facilitates low-loss and low-interference long-distance transmission to the local end through the backhaul test link. This avoids signal distortion caused by attenuation of high-frequency signals during long-distance cable transmission and solves the technical problem of low-distortion long-distance backhaul of high-frequency spatial transmission signals.

[0093] Figure 2 This is a flowchart of the second frequency domain response testing method according to an embodiment of the present invention, as follows: Figure 2 As shown, the method includes the following steps:

[0094] S202, Receive a response test request sent by the user terminal, wherein the response test request carries a frequency domain response test task;

[0095] This involves the user terminal, which is the device that initiates frequency domain response test requests to the main control terminal. The user terminal includes a test management computer, an operation terminal, or an automated test platform, and its main function is to provide an entry point for test task configuration and test process initiation.

[0096] This involves a response test request, which is a request sent by the user terminal to the main control terminal to start the frequency domain response test. The response test request includes data such as test task identifier and test parameter configuration, and its main function is to trigger the main control terminal to start executing the corresponding frequency domain response test process.

[0097] Among them, frequency domain response testing tasks are involved. These tasks are related to the frequency domain response characteristics of the tested objects such as radio frequency systems, antenna arrays, and microwave devices. They include amplitude frequency response characteristics and phase response characteristics, which are used for radio frequency related tests such as wireless channel measurement, microwave anechoic chamber probe calibration, array diagnostic calibration, and microwave material parameter measurement. The frequency domain response testing tasks include test frequency range, sampling space, and sweep frequency parameters.

[0098] By receiving response test requests sent by the user, the frequency domain response test task can be clearly defined, which will facilitate targeted testing later.

[0099] S204, in response to the response test request, determine the sampling point sequence corresponding to the frequency domain response test task;

[0100] This involves a sampling point sequence, which is a set of multiple test positions arranged in a certain order within the sampling space. For example, the sampling point sequence includes information such as the spatial coordinates, movement order, and execution number of each sampling point. Its main function is to define the test positions and execution order that the transmitting antenna on the 3D scanning gantry arrives at in sequence, so as to achieve complete coverage of the entire sampling space.

[0101] In response to the test request, the sequence of sampling points corresponding to the frequency domain response test task is determined to ensure that the transmitting antenna on the 3D scanning frame can reach each test position in sequence according to the predetermined trajectory, avoiding measurement omissions due to missing sampling point definitions or disordered order, thereby providing a complete position execution basis for the subsequent frequency domain response test of each sampling point.

[0102] S206, according to the execution order of each sampling point in the sampling point sequence, controls the transmitting antenna on the three-dimensional scanning frame to reach the corresponding sampling point, and sends the test execution command to the vector network analyzer;

[0103] This involves a transmitting antenna on a 3D scanning gantry. The transmitting antenna on the 3D scanning gantry is a radio frequency radiation unit (RF antenna) installed on the 3D scanning gantry. Specifically, the transmitting antenna can be a dual-polarized antenna, whose main function is to transmit the first radio frequency signal after frequency doubling into space after reaching the sampling point.

[0104] This involves a test execution command, which is a control command issued by the main control terminal to the vector network analyzer to start the test. This command triggers the vector network analyzer to start transmitting the first radio frequency signal and the first local oscillator signal after the transmitting antenna is in place, as well as receiving the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal.

[0105] Because the main control terminal controls the transmitting antenna on the 3D scanning frame to reach the corresponding sampling point according to the execution order of each sampling point in the sampling point sequence, and then sends the test execution command to the vector network analyzer, it can ensure that the transmitting antenna is in the correct position before triggering the vector network analyzer to start transmitting signals and receiving feedback. Therefore, it can avoid measurement deviations caused by misalignment, and at the same time ensure that the test timing and position positioning of each sampling point are accurately synchronized, thus providing a dual guarantee of position and timing for obtaining accurate frequency domain response data for each sampling point.

[0106] S208 receives a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal from a vector network analyzer. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal transmitted by the vector network analyzer. The auxiliary local oscillator signal is obtained based on the backward local oscillator signal transmitted along the signal return direction. The return mixing signal is obtained based on the test mixing signal transmitted along the signal return direction. The test mixing signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is obtained based on the first radio frequency signal after frequency multiplication transmitted by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point, transmitted along the transmission direction. The first radio frequency signal after frequency multiplication is the radio frequency signal after frequency multiplication of the first radio frequency signal. The second local oscillator signal is obtained based on the forward local oscillator signal transmitted along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained after signal splitting of the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

[0107] Since the reference mixing signal is directly determined based on the original transmitted first radio frequency signal and first local oscillator signal, the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal after splitting it from the same source along the signal return direction, and the return mixing signal is obtained by sequentially transmitting through space and mixing before being transmitted back, after the main control terminal receives the reference mixing signal, auxiliary local oscillator signal and return mixing signal fed back by the vector network analyzer, the main control terminal can simultaneously obtain three sets of related signals: the original reference, the link error characterization and the spatial transmission result. Thus, it can use the auxiliary local oscillator signal, which is from the same source and has the same frequency and phase, to compensate for the link phase drift and amplitude attenuation in the return mixing signal, thereby eliminating the measurement error introduced by long-distance transmission and frequency doubling, and solving the technical problem of inaccurate frequency domain response testing.

[0108] S210, based on the auxiliary local oscillator signal, corrects the return mixing signal to obtain the corrected mixing signal;

[0109] Among them, the correction of the return mixing signal is the process by which the main control terminal uses the auxiliary local oscillator signal to perform link error compensation on the return mixing signal. Its function is to eliminate the phase drift and amplitude attenuation introduced by the transmission link and obtain a pure signal that only reflects the spatial transmission characteristics.

[0110] This involves a corrected mixing signal, which is a signal obtained by correcting the return mixing signal, and is used as clean measurement data to compare with a reference mixing signal, in order to calculate the frequency domain response test results.

[0111] Since the link error in the auxiliary local oscillator signal and the return mixing signal originates from the same source, correcting the return mixing signal based on the auxiliary local oscillator signal can effectively eliminate the phase drift and amplitude attenuation introduced by the transmission link, and obtain a corrected mixing signal that only reflects the spatial transmission characteristics. This ensures that the subsequent comparison with the reference mixing signal is not affected by the link error, and solves the technical problem of measurement result distortion caused by link instability.

[0112] S212, based on the corrected mixing signal and the reference mixing signal, determines the test results of the corresponding sampling points until all sampling points have been processed, and obtains the frequency domain response test results.

[0113] The test results are obtained by comparing the corrected mixing signal with the reference mixing signal at a single sampling point. The test results include the amplitude frequency response and phase frequency response characteristics of the sampling point. The main function is to quantify and characterize the frequency domain transmission characteristics of the tested object at the sampling point.

[0114] This includes the frequency domain response test results, which are the final test results determined by comprehensively considering the test results of all sampling points. The frequency domain response test results include the amplitude frequency response data and phase frequency response data corresponding to each sampling point, which can comprehensively present the frequency domain response characteristics of the tested object in the entire sampling space.

[0115] Since the corrected mixing signal eliminates link errors and the reference mixing signal provides the original benchmark, the test results of a single sampling point are determined by comparing the two. This allows for the accurate acquisition of the amplitude-frequency response and phase-frequency response characteristics of the object under test at that location. By sequentially traversing each sampling point until all are completed, a complete frequency domain response test result covering the entire sampling space can be obtained. This fully restores the frequency domain transmission characteristics of the object under test in the entire sampling space and avoids measurement deviations caused by link errors.

[0116] Figure 3 This is a flowchart of the frequency domain response test method three according to an embodiment of the present invention, as follows: Figure 3 As shown, the method includes the following steps:

[0117] S302, after controlling the three-dimensional scanning frame to reach the corresponding sampling point through the main control terminal, receives the first radio frequency signal after frequency doubling;

[0118] S304, transmits a frequency-doubled first radio frequency signal, so that the frequency-doubled first radio frequency signal is transmitted along the signal transmission direction to obtain a second radio frequency signal, and determines a test mixing signal based on the second radio frequency signal and the second local oscillator signal, and obtains a return mixing signal based on the test mixing signal transmitted along the signal return direction, so that the main control terminal receives the return mixing signal, the reference mixing signal, and the auxiliary local oscillator signal, and determines the frequency domain response test result based on the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal. Among them, the frequency-doubled first radio frequency signal is obtained by frequency-doubled processing of the first radio frequency signal transmitted by the vector network analyzer, the second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction, the reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal transmitted by the vector network analyzer, the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction, the forward local oscillator signal and the backward local oscillator signal are obtained by signal splitting of the first local oscillator signal, and the forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

[0119] After the 3D scanning frame reaches the corresponding sampling point (which can be regarded as the transmitting antenna on the 3D scanning frame reaching the corresponding sampling point), the first radio frequency signal after frequency doubling is received and transmitted along the transmission direction to obtain the second radio frequency signal. Then, the test mixing signal is determined based on the second radio frequency signal and the transmitted second local oscillator signal, and the return mixing signal is transmitted along the return direction. At the same time, the main control terminal also receives the reference mixing signal directly determined based on the original signal and the auxiliary local oscillator signal obtained based on the return local oscillator signal. Therefore, the main control terminal can use the auxiliary local oscillator signal with the same source and the same frequency and phase to compensate for the link error in the return mixing signal and compare it with the reference mixing signal, thereby eliminating the measurement error introduced by long-distance transmission and frequency doubling, and thus accurately obtaining the frequency domain response test result of the sampling point.

[0120] Based on the above embodiments and optional embodiments, an optional implementation method is provided, which is described in detail below.

[0121] In related technologies, frequency domain response testing is a test for the object under test, such as antennas and arrays, anechoic chamber system calibration, and radio frequency devices and channel responses, in order to achieve a quantitative assessment of the transmission performance, spatial radiation characteristics and system distortion of the object under test. However, in related technologies, there is a technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on the object under test.

[0122] There is currently no effective solution to the above problems.

[0123] Specifically, the development of technologies such as ultra-large-scale antenna arrays, millimeter-wave / terahertz bands, ultra-wideband signal systems, and integrated sensing for 6G (6th Generation mobile communication systems) has placed higher demands on testing systems in the R&D and manufacturing processes. These demands include achieving high-precision amplitude and phase measurements over a wider frequency range, supporting long-distance test links, and coherent calibration and measurement of large-scale arrays. These testing requirements are widespread across various testing scenarios, including wireless channel measurement, synthetic aperture sensing, probe calibration in microwave anechoic chambers, array diagnostic calibration, and microwave material and device parameter measurement. Therefore, a universal testing method that can balance wideband, long-distance, and phase stability is urgently needed.

[0124] Vector Network Analyzers (VNAs) are general-purpose RF test instruments capable of simultaneously measuring amplitude and phase information. They feature wide frequency coverage, high frequency domain measurement accuracy, ease of calibration and de-embedding, and the ability to obtain complete complex parameters, making them widely used in antenna and array testing, anechoic chamber system calibration, and RF device and channel response measurement. However, traditional VNAs typically rely on coaxial cables to extend the test port to the distant test location. High-frequency coaxial cables suffer significantly increased loss per unit length, limiting test distance and reducing system dynamic range. Furthermore, large-scale array testing often requires long-duration, multi-location, or multi-channel coherent measurements; any instability in the link, such as temperature changes or mechanical stress, can introduce phase drift, thus reducing calibration and measurement accuracy. Therefore, VNA systems relying solely on traditional coaxial extension methods are insufficient to meet the testing requirements of next-generation broadband, long-distance, large-scale array systems.

[0125] Furthermore, RF links are sensitive to temperature changes and mechanical stress, easily introducing random phase variations. When frequency doubling / mixing is introduced to achieve coverage of arbitrary target frequency bands, the phase error of the local oscillator link is amplified by frequency doubling, making it even more difficult to achieve compatibility with long distances, wide bandwidth, and phase coherence. Related technologies often struggle to simultaneously achieve distance extension, wide bandwidth coverage, and phase coherence, making it difficult to develop a universal VNA long-distance wideband extension solution for various testing scenarios.

[0126] In view of this, an optional embodiment of the present invention provides a frequency domain response testing method, which can effectively solve the above-mentioned technical problems.

[0127] Figure 4 This is a schematic diagram of the frequency domain response test framework in an optional embodiment of the present invention. Figure 5 This is a schematic diagram of the frequency domain response testing method in an optional embodiment of the present invention, as shown below. Figure 4 and Figure 5 As shown, specifically, the local end of this frequency domain response test framework is equipped with various devices for controlling and / or performing frequency domain response tests, such as a master control terminal, a vector network analyzer, a 3D scanning rig, an upconverter, and a transmitting antenna on the 3D scanning rig; the remote end is equipped with a downconverter and a receiving antenna; and a forward test link ROF3, a backward test link ROF4, and a return test link ROF5 are also set between the near end and the remote end, which will be described in detail below.

[0128] S1, the main control terminal receives and responds to the response test request sent by the user terminal. The response test request carries a frequency domain response test task (including but not limited to probe calibration, array calibration, channel measurement, synthetic aperture spatial sampling and other test tasks that require spatial sampling), and determines the sampling point sequence corresponding to the frequency domain response test task. Then, according to the execution order of each sampling point in the sampling point sequence, the main control terminal controls the transmitting antenna on the three-dimensional scanning frame to reach the corresponding sampling point.

[0129] Specifically, the main control terminal generates the scanning trajectory offline based on the sampling space corresponding to the frequency domain response test task, determines the sampling point sequence corresponding to each sampling point, and determines the movement control parameters of the three-dimensional scanning frame (specifically, an electrically controlled three-dimensional scanning frame) at each sampling point, including spatial coordinates, displacement and motion command parameters, so as to control the transmitting antenna on the three-dimensional scanning frame to reach the corresponding sampling point.

[0130] The main control terminal is connected to the vector network analyzer and is used to control the frequency domain response test process and data acquisition.

[0131] The master control terminal is a dedicated control device with program control, including a processor, memory, at least one control output port, several communication ports, and one data input port. The memory in the master control terminal includes random access memory or non-volatile memory, and the non-volatile memory includes, but is not limited to, at least one disk storage device, used to store test control programs, scan trajectory information, and / or test data. The processor in the master control terminal is a general-purpose processor or a dedicated processor, including, but not limited to, a central processing unit (CPU), a network processor, as well as a digital signal processor, application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), other programmable logic devices, discrete gate or transistor logic devices, and discrete hardware components.

[0132] The 3D scanning gantry includes an electrical control system, an X-axis drive motor, a Y-axis drive motor, a Z-axis drive motor, and a control port. It is used to realize the movement of the transmitting antenna (specifically, the radio frequency antenna) in three-dimensional space (i.e., within the sampling space). The electrical control system is a programmable logic controller (PLC). The PLC is electrically connected to the control output port of the main control terminal through the control port of the 3D scanning gantry, so that the main control terminal can control the 3D scanning gantry to perform three-dimensional movement. That is, the main control terminal can control the electrical control system of the 3D scanning gantry, thereby driving the X-axis, Y-axis, and Z-axis drive motors to move the transmitting antenna on the 3D scanning gantry according to the movement control parameters.

[0133] For example, suppose the 3D scanning frame has sampling points at each point in a single test. In the discrete scan positions, the first... Spatial coordinates of each location for:

[0134]

[0135] in, These represent the coordinate components of the m-th discrete scanning position of the 3D scanning frame on the X-axis, Y-axis, and Z-axis in the 3D spatial coordinate system, respectively, used to uniquely determine the spatial position of the sampling point.

[0136] S2, after the transmitting antenna on the three-dimensional scanning frame reaches the corresponding sampling point, the main control terminal sends a test execution command to the vector network analyzer. After receiving and responding to the test execution command sent by the main control terminal, the vector network analyzer transmits the first radio frequency signal and the first local oscillator signal.

[0137] For example, the main control terminal controls the 3D scanning gantry to move the transmitting antenna sequentially along the scanning trajectory according to the scanning progress. After the 3D scanning gantry moves to the designated sampling point, the main control terminal sends a communication command (i.e., a test execution command) to the vector network analyzer, configures the frequency sweep parameters, and starts the measurement. This enables the vector network analyzer to synchronously or quasi-synchronously acquire data from the forward and backward test links during the scanning process, and outputs a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal to complete the measurement sampling at different spatial locations. The main control terminal can trigger the vector network analyzer to complete the data reading of the corresponding sampling point, or control the vector network analyzer to maintain a continuous reading mode.

[0138] The vector network analyzer can be a multi-port vector network analyzer, including at least one excitation port, one local oscillator source, and multiple receiving ports (specifically, at least four receiving ports), to support parameter measurement under wideband, multi-port conditions. Specifically, the vector network analyzer generates test signals (including a first radio frequency signal and a first local oscillator signal) and receives echo signals (including a reference mixer signal, an auxiliary local oscillator signal, and a return mixer signal) to obtain the frequency domain response characteristics of the object under test, such as amplitude and phase parameters. The excitation port is used to transmit the first radio frequency signal, the local oscillator source is used to transmit the first local oscillator signal, and the multiple receiving ports are used to receive the echo signals, supporting multi-port parameter measurement. The communication port of the main control terminal is connected to the communication port of the vector network analyzer to control the frequency sweep and measurement process of the vector network analyzer.

[0139] S3, the first local oscillator signal is divided into two paths. One path of the first local oscillator signal is transmitted to the up-converter to obtain the reference mixing signal and the first radio frequency signal after frequency multiplication. The other path of the first local oscillator signal enters the forward test link for transmission, and at the same time combines with the backward test link to obtain the second local oscillator signal and the auxiliary local oscillator signal.

[0140] The upconverter receives the first radio frequency signal and the first local oscillator signal, converts the first radio frequency signal and the first local oscillator signal to the corresponding target test frequency band, and obtains the frequency-doubled first radio frequency signal and the frequency-doubled first local oscillator signal. The frequency-doubled first radio frequency signal and the frequency-doubled first local oscillator signal are then mixed to obtain a reference mixed signal, which is then transmitted back to the vector network analyzer (specifically, the receiving port A of the vector network analyzer). The frequency-doubled first radio frequency signal is also transmitted to the transmitting antenna on the three-dimensional scanning frame.

[0141] The upconverter is deployed at a first location (i.e., the location corresponding to the local terminal). The spatial distance between the first location and the terminal location of the main control terminal is less than a first distance threshold, so that the upconverter is close to the main control terminal and / or the vector network analyzer, facilitating connection via a short cable and reducing transmission loss and interference. The upconverter includes a first frequency multiplier module and a first frequency mixer module. The first frequency multiplier module is used to multiply the first radio frequency signal to obtain a frequency-multiplied first radio frequency signal, and to multiply the first local oscillator signal to obtain a frequency-multiplied first local oscillator signal. The first frequency mixer module is used to mix the frequency-multiplied first radio frequency signal and the frequency-multiplied first local oscillator signal to obtain a reference mixed signal. Based on the upconverter, the vector network analyzer has configurable expansion capabilities for different target test frequency bands.

[0142] The input terminal of the upconverter is electrically connected to the excitation port of the vector network analyzer, and the output terminal of the upconverter (specifically the RF output terminal) is electrically connected to the transmitting antenna on the three-dimensional scanning frame. This is used to radiate the upconverted RF signal, that is, the first RF signal after frequency multiplication, into space through the transmitting antenna on the three-dimensional scanning frame, and to transmit the reference mixing signal back to the receiving port A of the vector network analyzer.

[0143] For example, the excitation port J of the vector network analyzer outputs a first radio frequency signal, and the excitation port S outputs a first local oscillator signal, wherein the frequency multiplication factor corresponding to the frequency multiplication processing is a positive integer. After frequency doubling, the high-frequency radio frequency (That is, the signal frequency of the first radio frequency signal after frequency doubling) and the high-frequency local oscillator (That is, the signal frequency of the first local oscillator signal after frequency doubling) are expressed as follows:

[0144]

[0145]

[0146] in, The frequency of the first local oscillator signal is also known as the local oscillator fundamental frequency.

[0147] Furthermore, the test configuration corresponding to the vector network analyzer satisfies the following:

[0148]

[0149] The first radio frequency signal after frequency multiplication and the first local oscillator signal after frequency multiplication are mixed to obtain the reference mixed signal. :

[0150]

[0151] The first local oscillator signal is divided into two paths, which can be achieved through a target distributor. The target distributor is electrically connected to the excitation port of the vector network analyzer and is used to distribute the test signal output by the vector network analyzer. Specifically, the target distributor is a power distributor, which can be the same as the power distributor in the forward test link.

[0152] The forward test link includes: a first electro-optical module, a first circulator, a second circulator, a power splitter, a first optical-to-electrical module, and a first optical fiber. The power splitter is connected between the first electro-optical module and the first optical-to-electrical module through the first optical fiber.

[0153] The backward test link includes: a first circulator, a second optical fiber, and a second optical-to-electrical module. The first circulator is connected between the first electrical-to-optical module and the power divider via the first optical fiber. The second circulator is connected between the first circulator and the power divider via the first optical fiber, and the first circulator is connected to the second optical-to-electrical module via the second optical fiber.

[0154] Specifically, the first local oscillator signal is electro-optically converted by the first electro-optical module to obtain the local oscillator optical signal; the local oscillator optical signal is transmitted to the power divider in the forward test link through the first optical fiber, and the power divider is used to divide the transmitted local oscillator optical signal into a forward local oscillator signal and a backward local oscillator signal;

[0155] The forward local oscillator signal is transmitted to the first optical fiber to the first optical-to-electric module, and the transmitted forward local oscillator signal is photoelectrically converted by the first optical-to-electric module to obtain the second local oscillator signal.

[0156] The backward local oscillator signal is transmitted along the signal return direction (back to the vector network analyzer, specifically the receiving port D of the vector network analyzer) through the backward test link so that the vector network analyzer can obtain an auxiliary local oscillator signal.

[0157] Meanwhile, the receiving port C of the vector network analyzer stores the first local oscillator signal that has not yet been transmitted as a reference. By using the data from receiving port C and receiving port D, the system parameters of radio frequency systems, such as optical links in long-distance systems, can be obtained.

[0158] It should be noted that the first and second optical fibers are the same type of optical fiber.

[0159] Since frequency doubling amplifies the phase disturbance of the local oscillator link, the local oscillator link is included in the phase error characterization range of the backward test link. Alternatively, a signal with equivalent perturbation to the local oscillator link can be included in the backward test link. This allows the backward test link to characterize the phase change before frequency doubling and compensate for the phase error caused by frequency doubling, thereby improving phase consistency across different target test frequency bands. In other words, the forward test link is used to transmit the forward local oscillator signal to obtain the response information of the object under test; the backward test link can transmit the backward local oscillator signal under conditions where it shares a long optical fiber with the forward test link or experiences equivalent fiber perturbation. In this system, the backward test link shares a long optical fiber or is transmitted with the forward test link through a circulator (such as a first circulator, a second circulator, or specifically an optical ring transmission device). This allows the backward local oscillator signal and the forward local oscillator signal to experience the same phase perturbation in the long optical fiber. Thus, fiber phase compensation is achieved through the forward and backward test links to characterize the phase error introduced by the optical fiber, thereby suppressing the influence of fiber phase drift on the test results and improving phase consistency under long-distance test conditions.

[0160] S4, the transmitting antenna on the three-dimensional scanning frame receives the first radio frequency signal after frequency doubling, and transmits the first radio frequency signal after frequency doubling to a distant end (e.g., radiates the first radio frequency signal after frequency doubling outward) so that the first radio frequency signal after frequency doubling can be transmitted in a predetermined space.

[0161] The transmitting antenna on the 3D scanning gantry can be a transmitting and receiving radio frequency antenna, including at least one antenna element. The antenna element supports any type of dual-polarized antenna structure. Each dual-polarized antenna element has two mutually orthogonal polarized antenna ports to support the transmission or reception of dual-polarized signals.

[0162] S5, the remote receiving antenna receives the second radio frequency signal (obtained by transmitting the first radio frequency signal after frequency multiplication by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point along the transmission direction, that is, the radio frequency signal corresponding to the first radio frequency signal after frequency multiplication is transmitted in the predetermined space), and transmits the second radio frequency signal to the downconverter.

[0163] S6. After receiving the second RF signal and the second local oscillator signal, the downconverter performs frequency multiplication on the second local oscillator signal to obtain the frequency-multiplied second local oscillator signal. Then, it performs frequency mixing on the second RF signal and the frequency-multiplied second local oscillator signal to obtain the test mixed signal. After that, the test mixed signal is transmitted to the vector network analyzer through the backhaul test link so that the vector network analyzer can receive the backhaul mixed signal (obtained by transmitting the test mixed signal along the signal backhaul direction through the backhaul test link).

[0164] The downconverter includes a second frequency multiplier module and a second frequency mixer module. The second frequency multiplier module multiplies the frequency of the second local oscillator signal to obtain a frequency-multiplied second local oscillator signal. The second frequency mixer module mixes the frequency-multiplied second local oscillator signal and the second radio frequency signal to obtain a test mixed signal.

[0165] The backhaul test link includes: a third electro-optical module, a third optical fiber, and a third optical-to-electrical module. The third electro-optical module is connected to the third optical-to-electrical module via the third optical fiber.

[0166] Specifically, the second radio frequency signal is received by the receiving antenna and input to the downconverter. Combined with the second local oscillator signal obtained from the forward test link, the downconverter processes the signal and outputs a test mixed signal. This signal is then transmitted back to the vector network analyzer via the backhaul test link. This backhaul to the vector network analyzer involves: a third electro-optical module converting the test mixed signal into an optical signal (denoted as the test optical signal), which is then transmitted back via a third optical fiber (long optical fiber) to a third optical-to-electrical module. The third optical-to-electrical module converts the transmitted test optical signal into an electrical signal, obtaining the backhaul mixed signal, which is then transmitted back to the vector network analyzer (specifically, to the receiving port B of the vector network analyzer) to complete the amplitude and phase parameter measurements. The data received from receiving ports A and B enable amplitude and phase measurements of the system under long-distance conditions.

[0167] The downconverter's RF input is electrically connected to the receiving antenna, and its IF output is electrically connected to the return test link. This connection is used to receive and process the second local oscillator signal and the high-frequency RF signal (i.e., the second RF signal) propagated spatially by the receiving antenna. The receiving antenna, specifically a transmitting and receiving RF antenna, includes at least one antenna element. Each antenna element supports any type of dual-polarized antenna structure, and each dual-polarized antenna element has two mutually orthogonal polarized antenna ports to support the transmission or reception of dual-polarized signals.

[0168] The forward test link and the backhaul test link can adopt the same radio-fiber transmission configuration as the forward test link to reduce system hardware complexity and ensure consistent long-distance transmission performance. The forward test link, the backhaul test link, and the backhaul test link together constitute the radio-fiber transmission module. Specifically, the radio-fiber transmission module includes at least two sets of electro-optical conversion modules (i.e., electro-to-optical modules, such as the first electro-to-optical module and the third electro-to-optical module) and at least three sets of opto-electric conversion modules (i.e., opto-to-electrical modules, such as the first opto-to-electrical module, the second opto-to-electrical module, and the third opto-to-electrical module). The electrical ports of the electro-to-optical modules are electrically connected to the ports of the vector network analyzer or the frequency converters (including up-converters and down-converters), and the optical ports are optically connected to the optical ports of the corresponding opto-to-electrical modules via long optical fibers (such as the first optical fiber, the second optical fiber, and the third optical fiber). Specifically, the electrical port of the first electro-to-optical module is electrically connected to the local oscillator port of the vector network analyzer; the electrical port of the third electro-to-optical module is electrically connected to the port of the down-converter. The optical port of the electro-optical conversion module is optically connected to the optical port of the corresponding photoelectric conversion module via a long optical fiber, thereby realizing long-distance, low-loss transmission of signals in the long optical fiber.

[0169] S7, the vector network analyzer receives the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal, and feeds the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal back to the main control terminal;

[0170] S8: After receiving the reference mixing signal, auxiliary local oscillator signal, and return mixing signal from the vector network analyzer, the main control terminal corrects the return mixing signal based on the auxiliary local oscillator signal to obtain the corrected mixing signal. Based on the corrected mixing signal and the reference mixing signal, the test results of the corresponding sampling points are determined until all sampling points have been completed, and the frequency domain response test results are obtained.

[0171] Specifically, for the reference mixing signal The complex amplitude and phase are measured to obtain the measured object across the entire frequency vector. The complex response on the surface. That is, the transmitting antenna on the 3D scanning gantry moves to each... Upon completion of the measurement, the frequency domain response test results are obtained.

[0172] Specifically, the frequency domain response test results include the parameter information of the tested object and the broadband complex frequency response dataset. The measured object parameter information includes, but is not limited to, scattering parameters, array channel response, probe calibration coefficients, complex frequency response data obtained from spatial sampling, and its derived parameters. At the sampling point The corresponding first radio frequency signal frequency The complex frequency domain response of the object under test.

[0173] The broadband complex frequency response data set is equivalent to a set of data composed of... The array elements are composed of, and their positions are as follows: The virtual array measurement data can be used for array calibration, probe calibration, channel measurement, and synthetic aperture imaging / sensing, etc.

[0174] For example, the main control terminal receives and stores the reference mixing signal, auxiliary local oscillator signal, and return mixing signal fed back by the vector network analyzer. Based on the measurement data corresponding to the reference mixing signal, auxiliary local oscillator signal, and return mixing signal, the main control terminal marks the sampling points of the measurement data and optionally performs timestamp alignment and / or frequency point alignment processing. Based on the measurement data of the auxiliary local oscillator signal, the main control terminal characterizes the phase change introduced by long fiber transmission and performs phase compensation and / or de-embedding calibration on the measurement data of the return mixing signal to obtain phase-stable parameter information of the measured object.

[0175] Specifically, after the forward local oscillator signal is transmitted through the forward test link, a second local oscillator signal is obtained. Then, the second local oscillator signal, after frequency doubling, and the second radio frequency signal are mixed to obtain a test mixed signal, which is then transmitted back to the vector network analyzer to obtain a return mixed signal. It can be seen that the return mixed signal contains the frequency domain response of the test object and the forward test link error. Therefore, phase compensation and / or de-embedding calibration are performed based on the auxiliary local oscillator signal. That is, based on the auxiliary local oscillator signal, the complex measurement parameters of the forward and backward test links are obtained for phase compensation and / or de-embedding calibration, wherein:

[0176] Forward test links, backward test links (and return test links) can all be considered as fiber optic links. In fiber optic links, signal phase perturbations can be equivalent to propagation delay perturbations. The resulting phase change is expressed by the formula:

[0177]

[0178] in, Indicates the phase (complex argument) of an optical fiber link; This indicates phase disturbance in the fiber optic link; This indicates the signal frequency in the fiber optic link.

[0179] Therefore, after frequency doubling the second local oscillator signal to obtain the frequency-doubled second local oscillator signal, when the signal frequency of the second local oscillator signal is changed from... (That is, the local oscillator fundamental frequency) is increased to The phase perturbation is amplified proportionally, as shown in the formula:

[0180]

[0181] in, This indicates that when the signal frequency of the second local oscillator signal is changed from... Upgraded to Phase perturbation at time, This indicates the signal frequency of the second local oscillator signal after frequency doubling; This refers to the phase disturbance corresponding to the second local oscillator signal, which is the phase disturbance corresponding to the forward local oscillator signal after transmission through the forward test link.

[0182] In response, due to the proportionally amplified effect of phase perturbation, the complex measurement parameters of the forward test link... Represented as:

[0183]

[0184] in, Characterizes the frequency domain response (complex response) of the measured object; Characterizes the link transmission characteristics of the forward local oscillator signal in the forward test link (amplitude response of the forward test link), reflecting the amplitude attenuation or gain after transmission through the forward test link. The signal frequency of the second local oscillator signal after frequency doubling; These are the corresponding sampling points.

[0185] The auxiliary local oscillator signal has not undergone frequency doubling; therefore, the complex measurement parameters of the backward test link are... Represented as:

[0186]

[0187] in, Sampling points The corresponding backward local oscillator signal has the link transmission characteristics (complex response) in the backward test link. Sampling points The corresponding forward local oscillator signal exhibits transmission characteristics in the forward test link. Since the forward and backward local oscillator signals are derived from the same source as the first local oscillator signal, they have the same frequency. Therefore, the frequencies of the forward and backward local oscillator signals can be expressed as follows: (That is, the local oscillator fundamental frequency).

[0188] Furthermore, the complex measurement parameters of the backward test link Represented as:

[0189]

[0190]

[0191]

[0192]

[0193] in, The imaginary unit; To assist the phase disturbance corresponding to the local oscillator signal.

[0194] In this case, ignoring the variation of fiber amplitude with frequency, .

[0195] For example, Figure 6 This is a schematic diagram of the phase drift of the forward test link in an optional embodiment of the present invention. Figure 7 This is a schematic diagram of the phase drift of the backward test link in an optional embodiment of the present invention, as shown below. Figure 6 and Figure 7 As shown, the phase of the forward and backward test links under physical rotation and temperature drift conditions during testing is illustrated. Specifically, due to temperature drift or physical disturbance, the phase of each measurement (a total of 10 measurements) exhibited varying degrees of drift, and the phase responses of the two links can be observed to be multiples of each other. Relationship. In this regard, the link transmission characteristics can be characterized as:

[0196]

[0197] Finally, at the sampling point The signal frequency of the first radio frequency signal after frequency multiplication The complex frequency domain response of the tested object (i.e., the true complex response of the tested object at high frequencies) can be expressed as:

[0198]

[0199] Figure 8 This is a schematic diagram of the link phase result after phase compensation in an optional embodiment of the present invention, as shown below. Figure 8 As shown, the results of 10 measurements after phase compensation are presented. It can be seen that the phase error was controlled within 10 degrees, indicating that the phase compensation method used has good stability.

[0200] Taking the synthesis of a two-dimensional uniform circular array using a three-dimensional scanning frame and a high-frequency directional antenna as an example, Figure 9 This is a schematic diagram of the phase distribution of the main array elements in an optional embodiment of the present invention, such as... Figure 9 As shown, the measured phase is highly consistent with the theoretical phase, verifying the accuracy of the constructed array model and measurement method. Figure 10 This is a schematic diagram of the angle-time delay-power spectrum distribution obtained by measuring a uniform circular array in an optional embodiment of the present invention, as shown below. Figure 10As shown, this can be used to initially characterize the range of arrival angles of the received signal. Under phase-stable conditions, further algorithmic processing can be performed on the array signal. Figure 11 This is a schematic diagram of the angle-delay-power spectrum after array signal processing in an optional embodiment of the present invention, as shown below. Figure 11 As shown, the classic beamforming algorithm is used as an example to process the array signal. The angle-delay-power spectrum obtained shows a significant improvement in the resolution of the received signal in the angular dimension compared to the unprocessed result.

[0201] The above optional implementation methods can achieve at least the following beneficial effects:

[0202] (1) Compared with related technologies, the present invention receives a test execution command sent by the main control terminal, transmits a first radio frequency signal and a first local oscillator signal in response to the test execution command, and then receives a reference mixing signal, an auxiliary local oscillator signal and a feedback mixing signal, and feeds the reference mixing signal, the auxiliary local oscillator signal and the feedback mixing signal back to the main control terminal. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal, the auxiliary local oscillator signal is obtained based on the back-to-back local oscillator signal transmitted along the signal feedback direction, the feedback mixing signal is obtained based on the test mixing signal transmitted along the signal feedback direction, and the test mixing signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is the first local oscillator signal after frequency multiplication, transmitted by the transmitting antenna on the three-dimensional scanning frame after reaching the corresponding sampling point. The radio frequency (RF) signal is transmitted along the transmission direction. The first RF signal after frequency doubling is the RF signal obtained by frequency doubling the first RF signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by splitting the first local oscillator signal and have the same frequency and phase. This allows the main control terminal to simultaneously obtain the original mixing reference, the link transmission error characterization signal, and the actual mixing signal after spatial transmission. The auxiliary local oscillator signal with the same source split and the same phase is used to compensate for the link phase drift and amplitude attenuation in the return mixing signal, thereby eliminating the errors introduced by long-distance transmission and frequency doubling. This solves the technical problem of inaccurate frequency domain response testing when performing frequency domain response testing on RF systems in related technologies.

[0203] (2) Compared with related technologies, this invention introduces key technologies such as radio fiber transmission, frequency doubling / mixing frequency expansion, backward test link phase compensation and virtual array synthesis, realizing wide-band, long-distance large-scale array testing, ensuring the amplitude and phase stability frequency domain response measurement requirements of large-scale array systems under wide-band, long-distance conditions, and fully meeting the testing requirements of various application scenarios such as anechoic chamber calibration, antenna array testing, wireless channel measurement and synthetic aperture imaging and sensing. It is suitable for wide-band, long-distance and ultra-large-scale array system testing.

[0204] (3) Compared with related technologies, the present invention drives the transmitting and receiving radio frequency antennas to sample at multiple spatial locations through a three-dimensional scanning frame, thereby forming an "equivalent array / virtual array" composed of multiple scanning positions. At the same time, broadband frequency sweep is performed on the target frequency band in the frequency domain, and a backward test link is constructed through ROF4 to calibrate and compensate for the phase drift introduced by the long optical fiber in the forward link, which significantly improves the accuracy of the test.

[0205] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the present invention is not limited to the described order of actions, because according to the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to the present invention.

[0206] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0207] Example 2

[0208] According to embodiments of the present invention, a system for implementing the above-described frequency domain response testing method is also provided. Figure 12 This is a structural block diagram of a frequency domain response testing system according to an embodiment of the present invention, as shown below. Figure 12 As shown, the device includes a vector network analyzer 1202, a main control terminal 1204, and a transmitting antenna 1206 on a three-dimensional scanning rig. The device will be described in detail below.

[0209] The vector network analyzer 1202 is used to receive test execution commands sent by the master control terminal; in response to the test execution commands, it transmits a first radio frequency signal and a first local oscillator signal; it receives a reference mixing signal, an auxiliary local oscillator signal and a feedback mixing signal, and feeds back the reference mixing signal, the auxiliary local oscillator signal and the feedback mixing signal to the master control terminal.

[0210] The main control terminal 1204, connected to the aforementioned vector network analyzer 1202, is used to receive response test requests sent by the user terminal, wherein the response test request carries a frequency domain response test task; in response to the response test request, it determines the sampling point sequence corresponding to the frequency domain response test task; according to the execution order of each sampling point in the sampling point sequence, it controls the transmitting antenna on the three-dimensional scanning frame to reach the corresponding sampling point and sends a test execution command to the vector network analyzer; it receives the reference mixing signal, auxiliary local oscillator signal, and return mixing signal fed back by the vector network analyzer; based on the auxiliary local oscillator signal, it corrects the return mixing signal to obtain a corrected mixing signal; based on the corrected mixing signal and the reference mixing signal, it determines the test result of the corresponding sampling point until each sampling point is executed, and obtains the frequency domain response test result;

[0211] The transmitting antenna 1206 on the three-dimensional scanning rig is connected to the main control terminal 1204 and is used to receive and transmit the first radio frequency signal after the three-dimensional scanning rig reaches the corresponding sampling point under the control of the main control terminal.

[0212] It should be noted that the vector network analyzer 1202, the main control terminal 1204, and the transmitting antenna 1206 on the three-dimensional scanning frame are the same as the examples and application scenarios implemented in the frequency domain response test method, but are not limited to the content disclosed in the above embodiment 1.

[0213] Example 3

[0214] According to another aspect of the present invention, an electronic device is also provided, comprising: a processor; and a memory for storing processor-executable instructions, wherein the processor is configured to execute instructions to implement the frequency domain response testing method of any of the above embodiments.

[0215] Example 4

[0216] According to another aspect of the present invention, a computer-readable storage medium is also provided, which, when the instructions in the computer-readable storage medium are executed by a processor of an electronic device, enables the electronic device to perform the frequency domain response test method described above.

[0217] Example 5

[0218] According to another aspect of the present invention, a computer program product is also provided, including a computer program that, when executed by a processor, implements the steps of the frequency domain response testing method described above.

[0219] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0220] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0221] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0222] 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 units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0223] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0224] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it 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 all or 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, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0225] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A frequency domain response testing method, characterized in that, include: Receive test execution commands sent by the main control terminal; In response to the test execution command, a first radio frequency signal and a first local oscillator signal are transmitted; The system receives a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal, and feeds these signals back to the main control terminal. The main control terminal then determines the frequency domain response test result based on these signals. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal. The auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction. The return mixing signal is obtained by transmitting the test mixing signal along the signal return direction. The test mixing signal is determined based on the second radio frequency signal and the second local oscillator signal. The second radio frequency signal is obtained by transmitting the first radio frequency signal after frequency multiplication, which is transmitted along the transmission direction after the transmitting antenna on the three-dimensional scanning frame reaches the corresponding sampling point. The first radio frequency signal after frequency multiplication is the radio frequency signal after frequency multiplication of the first radio frequency signal. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by signal splitting of the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

2. The method according to claim 1, characterized in that, The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction through the forward test link, and the auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction through the backward test link. The forward test link includes: a first electro-optical module, a first circulator, a second circulator, a power divider, a first optical-to-electrical module, and a first optical fiber. The power divider is connected between the first electro-optical module and the first optical-to-electrical module through the first optical fiber. The backward test link includes: a first circulator, a second optical fiber, and a second optical-to-electrical module. The first circulator is connected between the first electrical-to-optical module and the power divider via the first optical fiber. The second circulator is connected between the first circulator and the power divider via the first optical fiber, and the first circulator is connected to the second optical-to-electrical module via the second optical fiber.

3. The method according to claim 2, characterized in that, The first optical fiber and the second optical fiber are the same type of optical fiber.

4. The method according to claim 1, characterized in that, The return mixing signal is obtained by transmitting the test mixing signal along the signal return direction through the return test link. The backhaul test link includes: a third electro-optical module, a third optical fiber, and a third optical-to-electrical module. The third electro-optical module is connected to the third optical-to-electrical module through the third optical fiber.

5. The method according to claim 1, characterized in that, The reference mixing signal is obtained by performing a first signal processing on the first radio frequency signal and the first local oscillator signal through an upconverter. The upconverter is deployed at a first location, and the spatial distance between the first location and the terminal location of the main control terminal is less than a first distance threshold. The first signal processing includes: By performing frequency multiplication on the first radio frequency signal, a frequency-multiplied first radio frequency signal is obtained; By performing frequency multiplication on the first local oscillator signal, the frequency-multiplied first local oscillator signal is obtained; The reference mixed signal is obtained by mixing the first radio frequency signal after frequency doubling and the first local oscillator signal after frequency doubling.

6. The method according to claim 1, characterized in that, The test mixing signal is obtained by performing a second signal processing on the second radio frequency signal and the second local oscillator signal through a downconverter. The downconverter is deployed at a second location, and the spatial distance between the second location and the terminal location of the main control terminal is greater than a second distance threshold. The second signal processing includes: By performing frequency multiplication on the second local oscillator signal, the frequency-multiplied second local oscillator signal is obtained; A test mixed signal is obtained by mixing the frequency-doubled second local oscillator signal and the second radio frequency signal.

7. A frequency domain response testing method, characterized in that, include: Receive a response test request sent by the user terminal, wherein the response test request carries a frequency domain response test task; In response to the response test request, determine the sampling point sequence corresponding to the frequency domain response test task; According to the execution order of each sampling point in the sampling point sequence, the transmitting antenna on the three-dimensional scanning frame is controlled to reach the corresponding sampling point, and the test execution command is sent to the vector network analyzer. The system receives a reference mixer signal, an auxiliary local oscillator signal, and a return mixer signal from the vector network analyzer. The reference mixer signal is determined based on a first radio frequency (RF) signal and a first local oscillator signal transmitted by the vector network analyzer. The auxiliary local oscillator signal is obtained by transmitting a backward local oscillator signal along the signal return direction. The return mixer signal is obtained by transmitting a test mixer signal along the signal return direction. The test mixer signal is determined based on a second RF signal and a second local oscillator signal. The second RF signal is obtained by transmitting a frequency-doubled first RF signal transmitted by the transmitting antenna on the 3D scanning gantry after reaching the corresponding sampling point along the transmission direction. The frequency-doubled first RF signal is a RF signal obtained by frequency-doubled processing of the first RF signal. The second local oscillator signal is obtained by transmitting a forward local oscillator signal along the signal transmission direction. The forward local oscillator signal and the backward local oscillator signal are obtained by signal splitting of the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase. Based on the auxiliary local oscillator signal, the return mixing signal is corrected to obtain the corrected mixing signal; Based on the corrected mixing signal and the reference mixing signal, the test results of the corresponding sampling points are determined until all sampling points are completed, and the frequency domain response test results are obtained.

8. A frequency domain response testing method, characterized in that, include: After the 3D scanning frame reaches the corresponding sampling point under the control of the main control terminal, it receives and transmits a frequency-doubled first radio frequency (RF) signal, which is then transmitted along the signal transmission direction to obtain a second RF signal. A test mixing signal is determined based on the second RF signal and the second local oscillator signal. A return mixing signal is obtained by transmitting the test mixing signal along the signal return direction. The main control terminal receives the return mixing signal, a reference mixing signal, and an auxiliary local oscillator signal. Based on the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal, the frequency domain response test result is determined. The first radio frequency signal after frequency multiplication is obtained by multiplying the first radio frequency signal emitted by the vector network analyzer. The second local oscillator signal is obtained by transmitting the forward local oscillator signal along the signal transmission direction. The reference mixing signal is determined based on the first radio frequency signal and the first local oscillator signal emitted by the vector network analyzer. The auxiliary local oscillator signal is obtained by transmitting the backward local oscillator signal along the signal return direction. The forward local oscillator signal and the backward local oscillator signal are obtained by splitting the first local oscillator signal. The forward local oscillator signal and the backward local oscillator signal have the same frequency and phase.

9. A frequency domain response testing system, characterized in that, include: The vector network analyzer is used to receive test execution commands sent by the main control terminal; In response to the test execution command, a first radio frequency signal and a first local oscillator signal are transmitted; Receive a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal, and feed back the reference mixing signal, the auxiliary local oscillator signal, and the return mixing signal to the main control terminal; The main control terminal is used to receive a response test request sent by the user terminal, wherein the response test request carries a frequency domain response test task; in response to the response test request, it determines a sampling point sequence corresponding to the frequency domain response test task; according to the execution order of each sampling point in the sampling point sequence, it controls the transmitting antenna on the three-dimensional scanning frame to reach the corresponding sampling point and sends a test execution command to the vector network analyzer; it receives a reference mixing signal, an auxiliary local oscillator signal, and a return mixing signal fed back by the vector network analyzer; based on the auxiliary local oscillator signal, it corrects the return mixing signal to obtain a corrected mixing signal; based on the corrected mixing signal and the reference mixing signal, it determines the test result of the corresponding sampling point until each sampling point is executed, and obtains the frequency domain response test result; The transmitting antenna on the 3D scanning rig is used to receive and transmit the first radio frequency signal after it has been frequency-doubled, once the 3D scanning rig reaches the corresponding sampling point under the control of the main control terminal.

10. An electronic device, characterized in that, include: processor; Memory used to store the processor's executable instructions; The processor is configured to execute the instructions to implement the frequency domain response test method as described in any one of claims 1 to 8.

11. A computer-readable storage medium, characterized in that, When the instructions in the computer-readable storage medium are executed by the processor of the electronic device, the electronic device is able to perform the frequency domain response test method as described in any one of claims 1 to 8.

12. A computer program product, characterized in that, It includes a computer program that, when executed by a processor, implements the steps of the frequency domain response test method as described in any one of claims 1 to 8.

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