An antenna polarization testing apparatus and method

Abstract

The application discloses an antenna polarization testing device and method, and relates to the technical field of antenna testing, wherein the polarization wave generating module comprises a linear polarization antenna unit combination arranged orthogonally, a bridge unit with variable phase, and a switch network; the switch network is used for receiving a control signal of a control module, and the input channel and the output channel of the bridge unit are selected by the control signal; the bridge unit is used for accessing the linear polarization antenna unit combination through the input channel selected by the switch network, and generating polarization electromagnetic wave signals with different polarization directions according to the linear polarization signals emitted by the linear polarization antenna unit combination; and the electromagnetic wave transceiving module is used for sending the polarization electromagnetic wave signals to the antenna to be tested, receiving the response signal amplitude value returned by the antenna to be tested, and calculating the axial ratio and the inclination angle of the antenna to be tested. Only one set of orthogonal linear polarization antennas is needed, and the antenna can be tested without testing the phase, so that the structure is simple, the measurement result is accurate, and the testing efficiency is high.

Description

Technical Field

[0001] This invention relates to the field of antenna testing technology, and specifically to an antenna polarization testing device and method. Background Technology

[0002] Circularly polarized antennas are widely used in satellite communications, radar, the Internet of Things (IoT), and RFID industries due to their excellent resistance to multipath interference, rain and fog attenuation, and attitude insensitivity. Here, polarization refers to the trajectory of the endpoint of the electromagnetic wave's electric field intensity vector at a fixed point in space as it changes over time. If the trajectory of the vector's endpoint is a straight line, it is called a linearly polarized wave; if the trajectory is a circle, it is called a circularly polarized wave; and if the trajectory is an ellipse, it is called an elliptically polarized wave.

[0003] The electromagnetic waves generated by what are commonly referred to as circularly polarized antennas are actually non-ideal circularly polarized waves, namely elliptical polarized waves. The ratio of the major axis to the minor axis of an elliptical polarized wave is called the axial ratio, which is a very important indicator of circularly polarized antennas. A larger axial ratio indicates that the major axis is longer and the minor axis is shorter, and therefore the polarization type is closer to linear polarization. Conversely, a smaller axial ratio indicates that the major axis and minor axis are closer in size, and therefore the polarization type is closer to ideal circular polarization. In some testing scenarios, there is another indicator called the ellipse tilt angle, which is the angle between the major axis of the ellipse and the X-axis. It is usually used to guide and optimize the design of the circularly polarized antenna under test.

[0004] There are generally three ways to test the axial ratio and tilt angle of circularly polarized antennas: 1. Polarization Pattern Method: The circularly polarized antenna under test is fixed, while a linearly polarized auxiliary antenna is rotated. Alternatively, the circularly polarized antenna under test can be rotated while the linearly polarized auxiliary antenna remains fixed. Since the antenna under test is not ideally circularly polarized, the energy received by the receiving antenna is not consistent during rotation. The ratio of its maximum to minimum level is the axial ratio of the antenna under test. If the test curve is represented in polar coordinates, the angle between the major axis and the X-axis is the tilt angle. This method requires a rotatable polarization turntable, and rotation can easily cause jitter, leading to amplitude and phase measurement errors, especially in the high-frequency millimeter-wave band where such jitter errors are more pronounced. Furthermore, because the measurement process requires a 360-degree rotation, the measurement efficiency is not high.

[0005] 2. Circular Polarized Antenna Method: This method uses two standard circularly polarized antennas with opposite rotation directions as auxiliary antennas. The antenna under test transmits, and the auxiliary antennas receive. The energy received by each auxiliary antenna with opposite rotation directions is measured, and the axial ratio is calculated using a formula. However, it cannot measure the tilt angle. This method requires high-performance standard circularly polarized antennas, which are difficult to manufacture and implement. Furthermore, it requires repeatedly replacing the two auxiliary antennas with opposite rotation directions, impacting testing efficiency.

[0006] 3. Amplitude-Phase Method: This method calculates the axial ratio and tilt angle of the antenna under test by measuring the amplitude and phase information transmitted or received by two orthogonal linearly polarized antennas and then substituting this information into a formula. This method requires testing the antenna's phase; however, phase testing in typical antenna testing environments is limited by the testing equipment, resulting in significant errors, especially in the high-frequency millimeter-wave band. Furthermore, phase testing is often impossible in certain antenna testing scenarios, thus this method also has limitations.

[0007] It can be seen that the above three methods require phase measurement, antenna rotation or installation, and replacement with a high-precision circularly polarized antenna during implementation, resulting in low antenna testing efficiency and low accuracy. Summary of the Invention

[0008] The purpose of this invention is to provide an antenna polarization testing device and method. By setting up a bridge unit with fixed phase change and switching the output phase of the bridge through a switching network, a set of orthogonal linearly polarized antennas can transmit or receive electromagnetic waves in multiple polarization directions for testing. Only one set of orthogonal linearly polarized antennas is needed, without changing the antennas. Antenna testing can be achieved by only testing the amplitude of the antennas and not the phase. The structure is simple, the measurement results are accurate, and the testing efficiency is high.

[0009] To achieve the above objectives, this application provides the following solution: On one hand, the present invention provides an antenna polarization testing device, including a polarization wave generation module, a control module, and an electromagnetic wave transceiver module, wherein: The polarized wave generation module includes an orthogonally arranged linearly polarized antenna element combination, a bridge element with a fixed phase difference, and a switching network, wherein: The switching network is used to receive control signals generated by the control module according to the test mode of the antenna under test, and to select the signal transmission channel of the bridge unit through the control signals; The bridge unit is used to generate polarized electromagnetic wave signals with different polarization directions, and to transmit polarized electromagnetic wave signals between the online polarized antenna unit combination and the electromagnetic wave transceiver module according to the selected signal transmission channel. The electromagnetic wave transceiver module is used to send test signals to the polarization wave generation module or the antenna under test according to the test mode of the antenna under test, and to receive the electromagnetic wave response signals returned in response to the test signals to calculate the axial ratio and tilt angle of the antenna under test.

[0010] In some specific implementations, the linearly polarized antenna element combination includes orthogonally arranged first and second linearly polarized antenna elements. The first linearly polarized antenna element is used to generate horizontally polarized electromagnetic wave signals, and the second linearly polarized antenna element is used to generate vertically polarized electromagnetic wave signals. The switching network includes a first switching network and a second switching network, and the bridge unit includes several signal transmission ports, wherein: The selection terminals of the first and second switching networks are respectively connected to the signal transmission ports of the bridge unit, and the signal transmission ports selected according to the control signal form a signal transmission channel for transmitting polarized electromagnetic wave signals with different polarization directions. The signal terminals of the first switching network are connected to the first linearly polarized antenna unit and the second linearly polarized antenna unit, respectively, and the signal terminals of the second switching network are connected to the electromagnetic wave transceiver module.

[0011] In some specific implementations, the bridge unit includes a ring bridge with four signal transmission ports: a first port, a second port, a sum port, and a difference port. The first and second ports are connected to the gating terminals of a first switching network, and the sum and difference ports are connected to the gating terminals of a second switching network. When the sum port and the first port are selected, a horizontally polarized electromagnetic wave signal is transmitted through the first port; when the sum port and the second port are selected, a vertically polarized electromagnetic wave signal is transmitted through the second port. When selecting the gating port, the first port, and the second port, polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the first port and the second port; when selecting the gating port, the first port, and the second port, two polarized electromagnetic wave signals with equal amplitude and a phase difference of 180 degrees are transmitted through the first port and the second port.

[0012] In some specific implementations, a 90-degree 3dB bridge is connected between the first switching network and the linearly polarized antenna element combination. The 90-degree 3dB bridge has four ports: a first access port, a second access port, a third access port, and a fourth access port. The first and second access ports are respectively connected to the signal terminals of the first switching network, and the third and fourth access ports are respectively connected to the first and second linearly polarized antenna elements. When the second switching network selects the sum or difference port, if the first switching network selects the first port and the first access port, then two polarized electromagnetic wave signals with equal amplitude and a 90-degree phase difference are transmitted through the third and fourth access ports. If the first switch network selects the first port and the second access terminal, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the third access terminal and the fourth access terminal.

[0013] In some specific implementations, the bridge unit includes a first bridge, a second bridge, and a third bridge. The first bridge, the second bridge, and the third bridge are all 90-degree 3dB bridges, and each includes four signal transmission ports, namely a first signal port, a second signal port, a third signal port, and a fourth signal port. The first signal port and the second signal port of the first bridge are respectively connected to the selection terminal of the second switching network. The third signal port and the fourth signal port of the first bridge are respectively connected to the second signal port of the second bridge and the first signal port of the third bridge. The first signal port of the second bridge and the second signal port of the third bridge are respectively connected to a load. The third signal port and the fourth signal port of the second bridge and the third bridge are respectively connected to the selection terminal of the first switching network.

[0014] In some specific implementations, when the second switching network selects the first signal port of the first bridge, the relative phases of the second bridge and the third bridge are as follows: the third signal port and the fourth signal port of the second bridge are 90 degrees and 0 degrees respectively, and the third signal port and the fourth signal port of the third bridge are 90 degrees and 180 degrees respectively. When the second switching network selects the second signal port of the first bridge, the relative phases of the second bridge and the third bridge are as follows: The third and fourth signal ports of the second bridge are 180 degrees and 90 degrees respectively, while the third and fourth signal ports of the third bridge are 0 degrees and 90 degrees respectively.

[0015] In some specific implementations, when the second switching network selects the first signal port of the first bridge, if the first switching network selects the third or fourth signal port of the second bridge, then the horizontally polarized electromagnetic wave signal is transmitted through the third or fourth signal port of the second bridge; if the first switching network selects the third or fourth signal port of the third bridge, then the vertically polarized electromagnetic wave signal is transmitted through the third or fourth signal port of the third bridge. If the first switching network simultaneously selects the third signal ports of the second bridge and the third bridge, then two polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the third signal ports of the second bridge and the third bridge. If the first switching network simultaneously selects the fourth signal ports of the second bridge and the third bridge, then two polarized electromagnetic wave signals with equal amplitude and a phase difference of 180 degrees are transmitted through the fourth signal ports of the second bridge and the third bridge. If the first switching network simultaneously selects the third signal port of the second bridge and the fourth signal port of the third bridge, or simultaneously selects the fourth signal port of the second bridge and the third signal port of the third bridge, then two polarized electromagnetic wave signals with equal amplitude and 90 degrees phase difference are transmitted through the second bridge and the third bridge. When the second switching network selects the second signal port of the first bridge and the first switching network simultaneously selects the third signal port of the second bridge and the fourth signal port of the third bridge, or simultaneously selects the fourth signal port of the second bridge and the third signal port of the third bridge, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the second bridge and the third bridge.

[0016] In some specific implementations, the first switching network is a phase-shifting network, and the bridge unit includes a 90-degree 3dB bridge. The 90-degree 3dB bridge includes four signal transmission ports, namely a first transmission port, a second transmission port, a third transmission port, and a fourth transmission port. The third and fourth transmission ports are respectively connected to the selection terminals of the phase-shifting network. The first and second transmission ports are respectively connected to the selection terminals of the second switching network. The signal terminals of the phase-shifting network are respectively connected to the first linearly polarized antenna unit and the second linearly polarized antenna unit. The second switching network selects the sum and difference ports of the 90-degree 3dB bridge according to the control signal. The phase-shifting network selects the third transmission port and / or the fourth transmission port according to the control signal, so as to connect the first linearly polarized antenna unit and / or the second linearly polarized antenna unit to the 90-degree 3dB bridge and match the phase of the signals connected to the 90-degree 3dB bridge.

[0017] In some specific implementations, when the second switching network selects the first transmission port and the phase shifting network selects the third or fourth transmission port, the horizontally polarized electromagnetic wave signal or the vertically polarized electromagnetic wave signal is transmitted through the third or fourth transmission port. The second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports, and matches the third and fourth transmission ports with 90-degree and 0-degree phases respectively. Two polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the third and fourth transmission ports. The second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports, and matches the third and fourth transmission ports with 0 degrees and 90 degrees of phase respectively. Two polarized electromagnetic wave signals with equal amplitude and 180 degrees of phase difference are transmitted through the third and fourth transmission ports. When the second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports and both are matched with 0 degrees of phase, two polarized electromagnetic wave signals with equal amplitude and 90 degrees of phase difference are transmitted through the third and fourth transmission ports. When the second switching network selects the second transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports and both are matched with a 0-degree phase, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the third and fourth transmission ports.

[0018] Secondly, this application provides an antenna polarization testing method, specifically including the following steps: S1. Configure the test equipment according to the test parameters and test modes of the antenna under test. The test parameters include the type of antenna under test and the operating frequency band. The test modes include the receiving mode and the transmitting mode. The test equipment is an antenna polarization test equipment as described in the first aspect. S2. When the test mode of the antenna under test is the receiving mode, the electromagnetic wave transceiver module generates a test signal according to the type of the antenna under test and the operating frequency band and sends it to the polarization wave generation module. The polarization wave generation module converts the test signal into polarized electromagnetic wave signals with different polarization directions and radiates them to the antenna under test. The electromagnetic wave transceiver module receives the electromagnetic wave response signal after the polarized electromagnetic wave signal is converted by the antenna under test, and calculates the axial ratio and tilt angle of the antenna under test. S3. When the test mode of the antenna under test is the transmit mode, the electromagnetic wave transceiver module sends a test signal to the antenna under test, and the antenna under test converts the test signal into an electromagnetic wave signal. The polarization wave generation module converts the electromagnetic wave signal received from the antenna under test into polarized electromagnetic wave signals with different polarization directions and sends them to the electromagnetic wave transceiver module. The electromagnetic wave transceiver module calculates the axial ratio and tilt angle of the antenna under test based on the polarized electromagnetic wave signals with different polarization directions.

[0019] The beneficial effects of this invention are as follows: This invention requires only a set of orthogonal linearly polarized antennas (such as conventional dual-polarized horn antennas), a bridge unit with variable phase, and a switch network combination. By controlling the switches to generate two sets of orthogonal linearly polarized waves, various performance indicators of circularly polarized antennas can be tested without rotating or replacing the antenna, thus greatly improving testing efficiency. Furthermore, by adding a 90-degree 3dB bridge, circularly polarized waves can also be generated to determine the rotation direction of the antenna under test.

[0020] This invention requires only one set of orthogonal linearly polarized antennas and does not require measuring the antenna phase. This avoids the scenario where the axial ratio and tilt angle of a circularly polarized antenna cannot be tested due to the inability to measure the phase. In most testing scenarios, the phase accuracy of the testing equipment is much worse than the amplitude accuracy. The method of measuring the phase will lead to a deterioration in the accuracy of the axial ratio and tilt angle. This invention only needs to test the amplitude of two sets of orthogonal linearly polarized waves to obtain the axial ratio and tilt angle. It does not require the manufacture of high-precision standard circularly polarized antennas, which are difficult to manufacture and costly. It is simple, efficient and accurate. At the same time, it does not require the additional use of rotating antennas under test or auxiliary antennas, avoiding the introduction of amplitude and phase jitter caused by rotation. This invention is applicable to various testing scenarios for linearly polarized antennas. It can be used not only for testing circularly polarized antennas but also for testing linearly polarized antennas because the polarization wave generation module itself generates linearly polarized waves. By switching the electromagnetic wave signal output in different polarization directions through the switching network, it can be directly used for testing various indicators of linearly polarized antennas, avoiding the need to repeatedly replace the reference antenna. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure and connection of an antenna polarization testing device provided in Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the structure and connection of another antenna polarization testing device provided in Embodiment 2 of the present invention; Figure 3 This is a schematic diagram of the structure and connection of another antenna polarization testing device provided in Embodiment 3 of the present invention; Figure 4 This is a schematic diagram of the structure and connection of another antenna polarization testing device provided in Embodiment 4 of the present invention; Figure 5 This is a schematic diagram of the structure and connection of another antenna polarization testing device provided in Embodiment 5 of the present invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention.

[0024] At the same time, it should be understood that, for ease of description, the dimensions of the various parts shown in the accompanying drawings are not drawn according to actual scale.

[0025] Furthermore, for clarity and brevity, descriptions of well-known structures, functions, and configurations may have been omitted. Those skilled in the art will recognize that various changes and modifications can be made to the examples described herein without departing from the spirit and scope of this disclosure.

[0026] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0027] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0028] Example 1 like Figure 1 As shown, this embodiment provides an antenna polarization testing device, including a polarization wave generation module, a control module, and an electromagnetic wave transceiver module, wherein: The control module is used to generate control signals and control the switch network to select the signal transmission channel that needs to be enabled. The polarized wave generation module includes an orthogonally arranged linearly polarized antenna element combination, a bridge element with a fixed phase difference, and a switching network, wherein: The switching network is used to receive control signals generated by the control module according to the test mode of the antenna under test, and to select the signal transmission channel of the bridge unit through the control signals; It is understood that in this embodiment, the switch network includes a first switch network and a second switch network, and the bridge unit includes several signal transmission ports, wherein: The selection terminals of the first and second switching networks are respectively connected to the signal transmission ports of the bridge unit, and the signal transmission ports selected according to the control signal form a signal transmission channel for transmitting polarized electromagnetic wave signals with different polarization directions. The signal terminals of the first switching network are connected to the first linearly polarized antenna unit and the second linearly polarized antenna unit, respectively, and the signal terminals of the second switching network are connected to the electromagnetic wave transceiver module.

[0029] The bridge unit is used to generate polarized electromagnetic wave signals with different polarization directions, and to transmit polarized electromagnetic wave signals between the online polarized antenna unit combination and the electromagnetic wave transceiver module according to the selected signal transmission channel. It is understandable that the bridge unit can access the linearly polarized antenna unit combination and the electromagnetic wave transceiver module according to the signal transmission channel selected by the switching network, and perform bidirectional transmission between the linearly polarized antenna unit combination and the electromagnetic wave transceiver module. It can generate polarized electromagnetic wave signals with different polarization directions from the signals received from the linearly polarized antenna unit combination or the electromagnetic wave transceiver module and send them to the electromagnetic wave transceiver module or the linearly polarized antenna unit combination. The linearly polarized antenna unit assembly includes a first linearly polarized antenna unit and a second linearly polarized antenna unit arranged orthogonally. The first linearly polarized antenna unit is used to generate horizontally polarized electromagnetic wave signals, and the second linearly polarized antenna unit is used to generate vertically polarized electromagnetic wave signals. The electromagnetic wave transceiver module includes a receiver and a signal source, which is used to send test signals to the polarization wave generation module or the antenna under test according to the test mode of the antenna under test, and to receive the electromagnetic wave response signals returned in response to the test signals to calculate the axial ratio and tilt angle of the antenna under test.

[0030] Specifically, when the test mode of the antenna under test is transmission test, a test signal is generated and sent to the antenna under test. The antenna under test converts the test signal into an electromagnetic wave signal and sends it to the polarization wave generation module. The polarization wave generation module converts the electromagnetic wave signal into polarized electromagnetic wave signals with different polarization directions and sends them to the electromagnetic wave transceiver module. The electromagnetic wave transceiver module calculates the axial ratio and tilt angle of the antenna under test based on the polarized electromagnetic wave signals with different polarization directions. When the test mode of the antenna under test is reception test, a test signal is generated and sent to the polarization wave generation module. The polarization wave generation module converts the test signal into polarized electromagnetic wave signals with different polarization directions and sends them to the antenna under test. At the same time, it receives the electromagnetic wave response signal returned from the antenna under test, and calculates the axial ratio and tilt angle of the antenna under test.

[0031] The principle of this implementation is that by using a bridge unit with a fixed phase difference between different signal transmission ports, different phases and amplitudes can be assigned to horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals to synthesize arbitrary polarized waves. Therefore, how to select the bridge unit is very important. In this embodiment, the bridge unit has four signal transmission ports as an example. Two of the signal transmission ports are connected to the selection terminal of the first switch network, and the other two signal transmission ports are connected to the selection terminal of the second switch network. When the two signal transmission ports connected to the first switch network input signals, one of the two signal transmission ports connected to the second switch network is selected for output. Conversely, when one of the two signal transmission ports connected to the second switch network inputs signals, the signals output by the two signal transmission ports connected to the first switch network are equal in magnitude but have a certain phase difference. One of the two signal transmission ports connected to the first switch network or both ports can be selected to output signals. In this way, the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal, which have equal amplitude and phase difference, output from the bridge unit can be injected into the first linearly polarized antenna unit and the second linearly polarized antenna unit respectively, so that the two signals can be combined to form signals with different polarization directions: When the amplitudes of the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal are equal and there is no phase difference, they can be combined to synthesize a +45-degree polarized electromagnetic wave signal. When the amplitudes of the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal are equal and there is a 180-degree phase difference, they can be combined to synthesize a -45-degree polarized electromagnetic wave signal. When the amplitudes of the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal are equal and there is a 90-degree phase difference, they can be combined to synthesize a right-hand circularly polarized electromagnetic wave signal. When the amplitudes of the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal are equal and there is a -90-degree phase difference, they can be combined to synthesize a left-hand circularly polarized electromagnetic wave signal. When only one of the horizontally polarized electromagnetic wave signal or the vertically polarized electromagnetic wave signal is selected and injected into the first linearly polarized antenna element or the second linearly polarized antenna element, the horizontally polarized electromagnetic wave signal or the vertically polarized electromagnetic wave signal is transmitted through the first linearly polarized antenna element or the second linearly polarized antenna element.

[0032] Example 2 Specifically, in this embodiment, such as Figure 2 As shown, the linearly polarized antenna unit assembly includes a first linearly polarized antenna unit and a second linearly polarized antenna unit. The first linearly polarized antenna unit is a horizontally polarized antenna unit used to output horizontally polarized signals, and the second linearly polarized antenna unit is a vertically polarized antenna unit used to output vertically polarized signals. Since a ring bridge can generate a phase difference of 0 degrees and 180 degrees, and since the synthesis of +45-degree polarized electromagnetic waves and -45-degree polarized electromagnetic waves requires a phase difference of 0 degrees and 180 degrees, this embodiment uses a ring bridge unit. The four ports of the ring bridge are: the first port p1, the second port p2, the sum port Σ, and the difference port Δ. The switching network includes a first switching network and a second switching network. The first switching network has two gating terminals and two signal terminals. The second switching network has two gating terminals. The two gating terminals of the second switching network are respectively connected to the sum port Σ and the difference port Δ. The two gating terminals of the first switching network are respectively connected to the first port p1 and the second port p2. The two signal terminals are respectively connected to the horizontally polarized antenna unit and the vertically polarized antenna unit.

[0033] When the first port p1 and the second port p2 are used as input channels, and the sum port Σ or the difference port Δ is used as the output channel; when the sum port Σ or the difference port Δ is used as the input channel, and the first port p1 and / or the second port p2 are used as the output channel; the relationship between the four ports of the ring bridge is as follows: When the input signal to the sum port Σ is selected, the output signal to the difference port Δ is zero, while the output signals to p1 and p2 are equal in amplitude and have no phase difference. When the input signal to the difference port Δ is selected, the output signal to the sum port Σ is zero, while the output signals to p1 and p2 are equal in amplitude and have a phase difference of 180 degrees. Conversely, due to the distinctness of the ring bridge, only when the input signals to p1 and p2 are equal in amplitude and phase (i.e., no phase difference) will the sum port Σ output the maximum signal, and the difference port Δ will have no signal output. When the input signals to p1 and p2 are equal in amplitude and opposite in phase (i.e., 180 degrees phase difference), the output signal to the difference port Δ will be the maximum signal, and the sum port Σ will have no signal output.

[0034] During testing, the control module controls the on / off state of the first and second switching networks, enabling the electromagnetic wave to switch arbitrarily between horizontal polarization, vertical polarization, +45-degree polarization, and -45-degree polarization. The specific working principle is as follows: When the control module controls the first switch network to connect the horizontally polarized antenna unit and the first port p1, and disconnect the vertically polarized antenna unit and the second port p2, and the second switch network connects the signal source and the sum port Σ or the difference port Δ, when the antenna under test is in the transmit mode test, the antenna under test radiates electromagnetic waves outward according to the test signal. The first linear polarization unit converts the electromagnetic wave signal radiated by the antenna under test into a horizontally polarized electromagnetic wave signal and sends it to the ring bridge. The ring bridge sends the horizontally polarized electromagnetic wave signal received from the first linear polarization unit to the electromagnetic wave transceiver module through the sum port or the difference port. Alternatively, when the antenna under test is in the receive mode test, the electromagnetic wave transceiver module transmits the test signal through the ring bridge and the first switch network to the first linearly polarized antenna unit through the sum port or the difference port, radiating horizontally polarized electromagnetic wave signals outward. The antenna under test converts the received horizontally polarized electromagnetic wave signal into an electromagnetic wave response signal and sends it to the electromagnetic wave transceiver module. When the control module controls the first switch network to connect the vertically polarized antenna unit and the second port p2, and disconnect the horizontally polarized antenna unit and the first port p1, and the second switch network connects the signal source and the sum port Σ or the difference port Δ, the ring bridge will send the vertically polarized electromagnetic wave signal received from the second linearly polarized unit to the electromagnetic wave transceiver module through the sum port or the difference port, or the electromagnetic wave transceiver module will send the test signal through the sum port or the difference port to the second linearly polarized antenna unit via the ring bridge and the first switch network, thereby radiating the vertically polarized electromagnetic wave signal to the outside. When the control module controls the first switch network to connect the horizontally polarized antenna unit and the first port p1, as well as the vertically polarized antenna unit and the second port p2, and the second switch network connects the signal source and the sum port Σ, when the antenna under test is in the transmit mode test, the bridge unit receives the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal with equal amplitude and no phase difference input from the first linearly polarized antenna unit and the second linearly polarized antenna unit, and synthesizes the +45 degree linearly polarized electromagnetic wave signal and sends it to the electromagnetic wave transceiver module through the sum port Σ. Alternatively, when the antenna under test is in the receive mode test, the electromagnetic wave transceiver module sends a test signal, and the test signal outputs the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal with equal amplitude and no phase difference to the first linearly polarized antenna unit and the second linearly polarized antenna unit through the sum port Σ, the first port p1 and the second port p2 of the ring bridge, and synthesizes the +45 degree linearly polarized electromagnetic wave signal in the air for transmission. When the control module controls the first switch network to connect the horizontally polarized antenna unit and the first port p1, as well as the vertically polarized antenna unit and the second port p2, and the second switch network to connect the signal source and the differential port Δ, when the antenna under test is in transmit mode, the bridge unit receives horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and 180-degree phase difference from the input of the first linearly polarized antenna unit and the second linearly polarized antenna unit. The combined -45-degree linearly polarized electromagnetic wave signal is sent to the electromagnetic wave transceiver module through the differential port Δ. Alternatively, when the antenna under test is in receive mode, the electromagnetic wave transceiver module sends a test signal. The test signal is output through the differential port Δ to the first linearly polarized antenna unit and the second linearly polarized antenna unit via the first port p1 and the second port p2 of the ring bridge. The combined -45-degree linearly polarized electromagnetic wave signal is then transmitted in the air.

[0035] Example 3 like Figure 3 As shown, the difference between this embodiment and Embodiment 2 is only that a 90-degree 3dB bridge is connected between the first switching network and the linearly polarized antenna unit combination. By adding the 90-degree 3dB bridge, left-hand / right-hand circularly polarized antennas can also be formed to determine the rotation direction of the antenna under test. The 90-degree 3dB bridge has four ports: the first input port p11 and the second input port p12 are connected to the signal input port of the first switching network, the third input port p13 is connected to the horizontally polarized antenna unit, and the fourth input port p14 is connected to the vertically polarized antenna unit. In this case, the relationship between the four ports of the circular bridge is as follows: When the sum port Σ is selected as the input, p1 and p2 output equal-amplitude, in-phase signals; when the differential port Δ is selected as the input, p1 and p2 output equal-amplitude, out-of-phase signals; conversely, when p1 and p2 input equal-amplitude, in-phase signals, the sum port Σ outputs the maximum signal. When equal-amplitude inverse signals are input to p1 and p2, the differential port Δ outputs the maximum signal.

[0036] The relationship between the four ports of the 90-degree 3dB bridge is as follows: When p11 is input, p13 and p14 output equal amplitude signals, with p14 lagging 90 degrees in phase compared to p13. When P12 is input, P13 and P14 output equal amplitude signals, with P14 leading P13 by 90 degrees in phase. The working principle of this embodiment is as follows: When the control module controls the first switch network to select the first access terminal p11 and the first port p1 while disconnecting the second access terminal p12 and the second port p2, and the second switch network connects the signal source and disconnects the signal source and the difference port Δ, or the second switch network connects the signal source and the difference port Δ and disconnects the signal source and the difference port Σ, when the antenna under test is in the receiving mode test, the test signal output by the electromagnetic wave transceiver module passes through the second switch network, the ring bridge, the first switch network, and the 90-degree 3dB bridge, and outputs horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and 90-degree phase difference to the first linearly polarized antenna unit and the second linearly polarized antenna unit, and finally synthesizes a right-hand circularly polarized electromagnetic wave for radiation. Alternatively, when the antenna under test is in the transmitting mode test, the horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals sent by the first linearly polarized antenna unit and the second linearly polarized antenna unit are sent to the ring bridge through the 90-degree 3dB bridge and the first switch network to synthesize a right-hand circularly polarized electromagnetic wave, and then sent to the electromagnetic wave transceiver module through the second switch network. When the control module controls the first switch network to connect the second access terminal p12 and the second port p2 while disconnecting the first access terminal p11 and the first port p1, and the second switch network connects the signal source and port Σ and disconnects the signal source and the difference port Δ, or the second switch network connects the signal source and the difference port Δ and disconnects the signal source and the difference port Σ, when the antenna under test is in the receiving mode test, the test signal output by the electromagnetic wave transceiver module passes through the second switch network, the ring bridge, the first switch network, and the 90-degree 3dB bridge, and outputs horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and a 90-degree phase difference to the first linearly polarized antenna unit and the second linearly polarized antenna unit, and finally synthesizes a left-hand circularly polarized electromagnetic wave for radiation. Alternatively, when the antenna under test is in the transmitting mode test, the horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals sent by the first linearly polarized antenna unit and the second linearly polarized antenna unit are sent to the ring bridge through the 90-degree 3dB bridge and the first switch network to generate a right-hand circularly polarized electromagnetic wave, which is then sent to the electromagnetic wave transceiver module through the second switch network.

[0037] The antenna under test is tested for received power under electromagnetic waves of these two directions of rotation. If the received power is high under right-hand circularly polarized electromagnetic waves, the antenna under test is a right-hand circularly polarized antenna. If the received power is high under left-hand circularly polarized electromagnetic waves, the antenna under test is a left-hand circularly polarized antenna.

[0038] Example 4 like Figure 4 As shown, the difference between Embodiment 4 and Embodiment 2 lies only in that the bridge unit in this embodiment consists of three 90-degree 3dB bridges. A 90-degree 3dB bridge can generate a phase difference of +90 degrees and -90 degrees. Since synthesizing +45-degree polarized electromagnetic waves and -45-degree polarized electromagnetic waves requires a phase difference of 0 degrees and 180 degrees, if one 90-degree 3dB bridge is insufficient, another set of ports is needed. This set uses a combination of 90-degree ports to generate a 180-degree phase difference, and a combination of 90-degree ports and -90-degree ports to generate a 0-degree phase difference. Therefore, the bridge unit in this embodiment includes three bridges, each a 90-degree 3dB bridge: a first bridge, a second bridge, and a third bridge. The four signal transmission ports of each 90-degree 3dB bridge are the first signal port, the second signal port, the third signal port, and the fourth signal port, with the following relationships: When the first signal port is input, the second signal port has no signal output. The third and fourth signal ports output signals with equal amplitude and a phase difference of 90 degrees, such as the fourth signal port lagging behind the third signal port by 90 degrees. When the second signal port is input, the first signal port has no signal output. The third and fourth signal ports output signals with equal amplitude and a phase difference of -90 degrees. The phase of the fourth signal port is 90 degrees ahead of the phase of the third signal port. Due to the mutuality of the devices, only the signal amplitudes input to the third signal port and the fourth signal port are equal and the phase difference is 90 degrees. For example, when the phase of the fourth signal port lags behind the third signal port by 90 degrees, the first signal port has the maximum signal output and the second signal port has no signal output. Only when the signal amplitudes input to the third and fourth signal ports are equal and their phases differ by -90 degrees, such that the phase of the fourth signal port leads the phase of the third signal port by 90 degrees, and the second signal port has the maximum signal output while the first signal port has no signal output, will the signal output be minimized.

[0039] Specifically, such as Figure 4As shown, the first signal port p1(A) and the second signal port p2(A) of the first bridge are respectively connected to the second switching network. The third signal port p3(A) and the fourth signal port p4(A) of the first bridge are respectively connected to the second signal port p2(B) of the second bridge and the first signal port p1(C) of the third bridge. The first signal port p1(B) of the second bridge and the second signal port p2(C) of the third bridge are respectively connected to a load resistor (50Ω). The third signal port p3(B) and the fourth signal port p4(B) of the second bridge, as well as the third signal port p3(C) and the fourth signal port p4(C) of the third bridge, are respectively connected to the selection terminal of the first switching network.

[0040] The working principle of this embodiment is as follows: When the second switching network selects the first signal port p1(A) of the first bridge, the relative phases of the third signal port p3(B) and the fourth signal port p4(B) of the second bridge, and the third signal port p3(C) and the fourth signal port p4(C) of the third bridge are as follows: p3(B) = 90 degrees, p4(B) = 0 degrees, p3(C) = 90 degrees, p4(C) = 180 degrees; When the second switching network selects the second signal port p2(A) of the first bridge, the relative phases of p3(B), p4(B), p3(C), and p4(C) are as follows: p3(B) = 180 degrees, p4(B) = 90 degrees, p3(C) = 0 degrees, p4(C) = 90 degrees; Therefore, when the control module controls the second switch network to turn on p1(A), and the first switch network turns on p3(B) or p4(B) to turn on the horizontally polarized antenna unit and turns off p3(C) or p4(C) to turn off the vertically polarized antenna unit, the bridge unit transmits and receives horizontally polarized electromagnetic wave signals through the third signal port p3(B) or the fourth signal port p4(B) of the third bridge. When the control module controls the second switch network to connect p1(A), and the first switch network connects p3(C) or p4(C) to the vertically polarized antenna unit and p3(B) or p4(B) to disconnect the horizontally polarized antenna unit, the third signal port p3(C) or the fourth signal port p4(C) transmits and receives vertically polarized electromagnetic wave signals. When the control module controls the second switch network to turn on p1(A), and the first switch network turns on p3(B) to turn on the horizontally polarized antenna unit and p3(C) to turn on the vertically polarized antenna unit, the horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and no phase difference transmitted and received by p3(B) and p3(C) are combined into a +45-degree linearly polarized electromagnetic wave signal through the bridge unit when the antenna under test is in the transmit mode test, and then sent to the electromagnetic wave transceiver module through p1(A). When the antenna under test is in the receive mode test, the +45-degree linearly polarized electromagnetic wave signal is combined into a +45-degree linearly polarized electromagnetic wave signal through the first linearly polarized antenna unit and the second linearly polarized antenna unit and radiated to the antenna under test. When the control module controls the second switch network to turn on p1(A), and in the first switch network, p4(B) is turned on to the horizontally polarized antenna unit and p4(C) is turned on to the vertically polarized antenna unit, the horizontally polarized electromagnetic wave signals transmitted and received by p4(B) and p4(C) with equal amplitude and 180-degree phase difference are synthesized into a -45-degree linearly polarized electromagnetic wave signal through the bridge unit when the antenna under test is in the transmit mode test, and sent to the electromagnetic wave transceiver module through p1(A). When the antenna under test is in the receive mode test, the -45-degree linearly polarized electromagnetic wave signal is synthesized in the first and second linearly polarized antenna units and radiated to the antenna under test. When the control module controls the second switch network to connect p1(A), and in the first switch network, p4(B) is connected to the horizontally polarized antenna unit and p3(C) is connected to the vertically polarized antenna unit, or in the first switch network, p3(B) is connected to the horizontally polarized antenna unit and p4(C) is connected to the vertically polarized antenna unit, the second bridge and the third bridge transmit two polarized electromagnetic wave signals with equal amplitude and a 90-degree phase difference. When the antenna under test is in the transmit mode test, the bridge unit synthesizes a right-hand circularly polarized electromagnetic wave signal and sends it to the electromagnetic wave transceiver module through p1(A). When the antenna under test is in the receive mode test, the first linearly polarized antenna unit and the second linearly polarized antenna unit synthesize a right-hand circularly polarized electromagnetic wave signal and radiates it to the antenna under test. When the control module controls the second switch network to connect p2(A), and in the first switch network, p4(B) is connected to the horizontally polarized antenna unit and p3(C) is connected to the vertically polarized antenna unit, or in the first switch network, p3(B) is connected to the horizontally polarized antenna unit and p4(C) is connected to the vertically polarized antenna unit, the second bridge and the third bridge transmit two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees. When the antenna under test is in the transmit mode test, the bridge unit synthesizes a left-hand circularly polarized electromagnetic wave signal and sends it to the electromagnetic wave transceiver module through p2(A). When the antenna under test is in the receive mode test, the first linearly polarized antenna unit and the second linearly polarized antenna unit synthesize a left-hand circularly polarized electromagnetic wave signal and radiates it to the antenna under test.

[0041] Example 5 like Figure 5 As shown, the difference between Embodiment 5 and Embodiment 2 lies only in that the first switching network in this embodiment uses a phase-shifting network, directly using a fixed phase shifter to generate the required 0-degree or 180-degree phase difference. The bridge unit uses a 90-degree 3dB bridge, which includes four signal transmission ports: the third transmission port p23, the fourth transmission port p24, the first transmission port p21, and the second transmission port p22. The first transmission port p21 and the second transmission port p22 of the 90-degree 3dB bridge are respectively connected to the selection terminals of the second switching network. The third transmission port p23 and the fourth transmission port p24 of the 3dB bridge are respectively connected to the selection terminal of the phase-shifting network. The signal terminal of the phase-shifting network is respectively connected to the horizontally polarized antenna element and the vertically polarized antenna element. The second switching network selects the first transmission port p21 or the second transmission port p22 according to the control signal. The phase-shifting network selects the third transmission port p23 / or the fourth transmission port p24 according to the control signal, connects the first linearly polarized antenna element and / or the second linearly polarized antenna element to the bridge unit, and matches the phase of the signal connected to the 90-degree 3dB bridge.

[0042] The relationship between the four ports of the 90-degree 3dB bridge is as follows: When P21 is input, P23 and P24 output signals of equal amplitude, with P24 lagging 90 degrees in phase compared to P23; when P23 and P24 are input signals of equal amplitude, and P21 has the maximum signal output when P24 lags 90 degrees in phase compared to P23. When P22 is input, P23 and P24 output equal amplitude signals, with P24 leading P23 by 90 degrees in phase. P23 and P24 are input with equal amplitude signals. When the phase of P24 is 90 degrees ahead of P23, P22 has the maximum signal output.

[0043] The working principle of this embodiment is as follows: When the control module controls the second switch network to turn on p21 and turn off p22, and the phase shifting network to turn on p23 and turn off p24, the horizontally polarized electromagnetic wave signal is sent to the electromagnetic wave transceiver module through the first transmission port p21, or the electromagnetic wave transceiver module transmits the test signal through the first transmission port p21 to the first linearly polarized antenna unit via the third transmission port p23 of the bridge unit, and radiates the horizontally polarized electromagnetic wave signal to the outside. When the control module controls the second switch network to turn on p21 and turn off p22, and the phase shifting network to turn on p24 and turn off p23, the horizontally polarized electromagnetic wave signal is sent to the electromagnetic wave transceiver module through the first transmission port p21, or the electromagnetic wave transceiver module transmits the test signal through the first transmission port p21 to the second linearly polarized antenna unit via the fourth transmission port p24 of the bridge unit, and radiates the vertically polarized electromagnetic wave signal to the outside. When the control module controls the second switch network to turn on p21 and turn off p22, the phase shifting network to turn on p23 and match a 90-degree phase, and the phase shifting network to turn on p24 and match a 0-degree phase, the third transmission port p23 and the fourth transmission port p24 transmit and receive horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and no phase difference. When the antenna under test is in the transmit mode test, the +45-degree linearly polarized electromagnetic wave signal is synthesized by the bridge unit and sent to the electromagnetic wave transceiver module through p21. When the antenna under test is in the receive mode test, the +45-degree linearly polarized electromagnetic wave signal is synthesized in the first linearly polarized antenna unit and the second linearly polarized antenna unit and radiated to the antenna under test. When the control module controls the second switch network to turn on p21 and turn off p22, the phase shifting network to turn on p23 and match 0 degrees of phase, and the phase shifting network to turn on p24 and match 90 degrees of phase, the horizontally polarized electromagnetic wave signal and the vertically polarized electromagnetic wave signal with equal amplitude and 180 degrees of phase difference are transmitted and received by the third transmission port p23 and the fourth transmission port p24. When the antenna under test is in the transmit mode test, the -45 degree linearly polarized electromagnetic wave signal is synthesized by the bridge unit and sent to the electromagnetic wave transceiver module through p21. When the antenna under test is in the receive mode test, the -45 degree linearly polarized electromagnetic wave signal is synthesized in the first linearly polarized antenna unit and the second linearly polarized antenna unit and radiated to the antenna under test. When the control module controls the second switch network to connect p21 and disconnect p22, the phase shifting network to connect p23 and match 0 degrees of phase, and the phase shifting network to connect p24 and match 0 degrees of phase, the third transmission port p23 and the fourth transmission port p24 transmit horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and a phase difference of 90 degrees. When the antenna under test is in transmit mode, a right-hand circularly polarized electromagnetic wave signal is synthesized through the bridge unit and sent to the electromagnetic wave transceiver module through p21. When the antenna under test is in receive mode, a right-hand circularly polarized electromagnetic wave signal is synthesized in the first linearly polarized antenna unit and the second linearly polarized antenna unit and radiated to the antenna under test. When the control module controls the second switch network to connect p22 and disconnect p21, the phase shifting network to connect p23 and match 0 degrees of phase, and the phase shifting network to connect p24 and match 0 degrees of phase, the third transmission port p23 and the fourth transmission port p24 transmit horizontally polarized electromagnetic wave signals and vertically polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees. When the antenna under test is in transmit mode, the left-hand circularly polarized electromagnetic wave signal is synthesized by the bridge unit and sent to the electromagnetic wave transceiver module through p22. When the antenna under test is in receive mode, the left-hand circularly polarized electromagnetic wave signal is synthesized in the first linearly polarized antenna unit and the second linearly polarized antenna unit and radiated to the antenna under test.

[0044] Example 6 This embodiment, based on the test equipment of embodiments 1-5, provides an antenna polarization test method. It generates different control signals through a control module, producing electromagnetic wave signals with different polarization directions. This method can be used for circular antenna polarization testing as well as conventional antenna polarization testing. Specifically, it includes the following steps: S1. Configure the test equipment according to the test parameters and test mode of the antenna under test. The test parameters include the type and operating frequency band of the antenna under test. The test mode includes the receiving mode and the transmitting mode. The test equipment is an antenna polarization test equipment as described in any of Examples 1-5. S2. When the test mode of the antenna under test is the receiving mode, the electromagnetic wave transceiver module generates a test signal according to the type of the antenna under test and the operating frequency band and sends it to the polarization wave generation module. The polarization wave generation module converts the test signal into polarized electromagnetic wave signals with different polarization directions and radiates them to the antenna under test. The electromagnetic wave transceiver module receives the electromagnetic wave response signal after the polarized electromagnetic wave signal is converted by the antenna under test, and calculates the axial ratio and tilt angle of the antenna under test. S3. When the test mode of the antenna under test is the transmit mode, the electromagnetic wave transceiver module sends a test signal to the antenna under test, and the antenna under test converts the test signal into an electromagnetic wave signal. The polarization wave generation module converts the electromagnetic wave signal received from the antenna under test into polarized electromagnetic wave signals with different polarization directions and sends them to the electromagnetic wave transceiver module. The electromagnetic wave transceiver module calculates the axial ratio and tilt angle of the antenna under test based on the polarized electromagnetic wave signals with different polarization directions.

[0045] Specifically, when the antenna under test is a circularly polarized antenna, if the control signals of the switching network are generated sequentially according to the working principle in Example 2, the polarization wave generation module sequentially generates horizontally polarized electromagnetic wave signals, vertically polarized electromagnetic wave signals, +45-degree polarized electromagnetic wave signals, and -45-degree polarized electromagnetic wave signals, which are then sent to the circularly polarized antenna under test through the electromagnetic wave transceiver module. Simultaneously, the response signal amplitude values ​​E1~E4 returned by the circularly polarized antenna under test are received. During testing, the control module can arbitrarily switch the electromagnetic wave between horizontal polarization, vertical polarization, +45-degree polarization, and -45-degree polarization by controlling the on / off state of the first and second switching networks. The specific process is as follows: When the control module controls the first switch network to connect the horizontally polarized antenna unit and the first port p1, and disconnect the vertically polarized antenna unit and the second port p2, and the second switch network connects the signal source and the sum port Σ or the difference port Δ, the polarization wave generation module generates a horizontally polarized electromagnetic wave signal: ; When the control module controls the first switch network to connect the vertically polarized antenna unit and the second port p2, and disconnect the horizontally polarized antenna unit and the first port p1, and the second switch network connects the signal source and the sum port Σ or the difference port Δ, the polarization wave generation module generates a vertically polarized electromagnetic wave signal: ; When the control module controls the first switch network to connect the horizontally polarized antenna unit and the first port p1, as well as the vertically polarized antenna unit and the second port p2, and the second switch network connects the signal source and port Σ, the polarization wave generation module generates a +45 degree polarized electromagnetic wave signal. : When the control module controls the first switch network to connect the horizontally polarized antenna element and the first port p1, as well as the vertically polarized antenna element and the second port p2, and the second switch network connects the signal source and the difference port Δ, the polarization wave generation module generates a -45-degree polarized electromagnetic wave signal. : When the polarization wave generation module transmits a horizontally polarized electromagnetic wave signal to the antenna under test, the amplitude of the response signal received from the antenna under test is expressed in terms of electric field strength (unit: V / m), denoted as . E 1; When the polarized wave generation module transmits a vertically polarized electromagnetic wave signal, the electric field intensity received from the antenna under test is denoted as: E 2; When the polarized wave generation module transmits a +45 degree polarized electromagnetic wave signal, the electric field strength received from the antenna under test is denoted as: E 3; When the polarized wave generation module transmits a -45 degree polarized electromagnetic wave signal, the electric field strength received from the antenna under test is denoted as: E 4; At this point, the axial ratio AR (in dB) of the antenna under test can be directly calculated using the following formula: The tilt angle θ (in degrees) of the antenna under test can be calculated using the following formula: .

[0046] As can be seen, in this embodiment, the axial ratio and tilt angle of the antenna under test can be calculated without measuring the phase, thereby avoiding the scenario where the axial ratio and tilt angle of a circularly polarized antenna cannot be tested due to the inability to test the phase.

[0047] To test the rotation direction of the circularly polarized antenna under test, the equipment in Example 2 can be used to test the received power of the circularly polarized antenna under test under electromagnetic waves of these two rotation directions. If the received power is high under right-hand circularly polarized electromagnetic waves, the antenna under test is a right-hand circularly polarized antenna. If the received power is high under left-hand circularly polarized electromagnetic waves, the antenna under test is a left-hand circularly polarized antenna.

[0048] When the type of the antenna under test is a conventional linearly polarized antenna, for example, when the antenna under test is a horizontally polarized antenna, it is only necessary to configure the test parameters of the control module to control the first switch network to connect the horizontally polarized antenna unit and the first port p1, disconnect the vertically polarized antenna unit and the second port p2, and connect the signal source and the sum port Σ or the difference port Δ, so that the polarization wave generation module generates a horizontally polarized electromagnetic wave signal. When the antenna under test is a vertically polarized antenna, the control module controls the first switch network to connect the vertically polarized antenna unit and the second port p2, and disconnect the horizontally polarized antenna unit and the first port p1. When the second switch network connects the signal source and the sum port Σ or the difference port Δ, the polarization wave generation module generates a vertically polarized electromagnetic wave signal.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Based on the technical essence of the present invention, any simple modifications, equivalent substitutions, and improvements made to the above embodiments within the spirit and principles of the present invention shall still fall within the protection scope of the present invention.

Claims

1. An antenna polarization testing device, characterized in that, It includes a polarization wave generation module, a control module, and an electromagnetic wave transceiver module, wherein: The polarization wave generation module includes an orthogonally arranged linearly polarized antenna element assembly, a bridge unit with a fixed phase difference, and a switching network. The linearly polarized antenna element assembly includes an orthogonally arranged first linearly polarized antenna element and a second linearly polarized antenna element. The first linearly polarized antenna element is used to generate horizontally polarized electromagnetic wave signals, and the second linearly polarized antenna element is used to generate vertically polarized electromagnetic wave signals, wherein: The switching network is used to receive control signals generated by the control module according to the test mode of the antenna under test, and to select the signal transmission channel of the bridge unit through the control signals; The switching network includes a first switching network and a second switching network, and the bridge unit includes several signal transmission ports, wherein: The selection terminals of the first and second switching networks are respectively connected to the signal transmission ports of the bridge unit, and the signal transmission ports selected according to the control signal form a signal transmission channel for transmitting polarized electromagnetic wave signals with different polarization directions. The signal terminals of the first switching network are connected to the first linearly polarized antenna unit and the second linearly polarized antenna unit, respectively, and the signal terminals of the second switching network are connected to the electromagnetic wave transceiver module. The bridge unit is used to generate polarized electromagnetic wave signals with different polarization directions and transmits these signals between the linearly polarized antenna unit assembly and the electromagnetic wave transceiver module according to the selected signal transmission channel. The different signal transmission ports of the bridge unit have a fixed phase difference, assigning different phases and amplitudes to the horizontally polarized and vertically polarized electromagnetic wave signals to synthesize polarized waves with different directions. The horizontally polarized and vertically polarized electromagnetic wave signals output by the bridge unit, with equal amplitude and a phase difference, are then fed into the first and second linearly polarized antenna units, respectively, allowing the two signals to be combined to form signals with different polarization directions. These signals include horizontally polarized electromagnetic wave signals, vertically polarized electromagnetic wave signals, +45-degree linearly polarized electromagnetic wave signals, and -45-degree linearly polarized electromagnetic wave signals. The electromagnetic wave transceiver module is used to send test signals to the polarization wave generation module or the antenna under test according to the test mode of the antenna under test, and to receive the electromagnetic wave response signals returned in response to the test signals. It obtains the response signal amplitude values ​​corresponding to signals with different polarization directions, and calculates the axial ratio and tilt angle of the antenna under test based solely on the response signal amplitude values.

2. The antenna polarization testing device according to claim 1, characterized in that, The bridge unit includes a ring bridge with four signal transmission ports: a first port, a second port, a sum port, and a difference port. The first and second ports are connected to the gating terminals of a first switching network, and the sum and difference ports are connected to the gating terminals of a second switching network. When the sum port and the first port are selected, a horizontally polarized electromagnetic wave signal is transmitted through the first port; when the sum port and the second port are selected, a vertically polarized electromagnetic wave signal is transmitted through the second port. When selecting the gating port, the first port, and the second port, polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the first port and the second port; when selecting the gating port, the first port, and the second port, two polarized electromagnetic wave signals with equal amplitude and a phase difference of 180 degrees are transmitted through the first port and the second port.

3. The antenna polarization testing device according to claim 2, characterized in that, A 90-degree 3dB bridge is connected between the first switching network and the linearly polarized antenna element combination. The 90-degree 3dB bridge has four ports: a first access port, a second access port, a third access port, and a fourth access port. The first and second access ports are respectively connected to the signal terminals of the first switching network, and the third and fourth access ports are respectively connected to the first and second linearly polarized antenna elements. When the second switching network selects the sum or difference port, if the first switching network selects the first port and the first access port, then two polarized electromagnetic wave signals with equal amplitude and a 90-degree phase difference are transmitted through the third and fourth access ports. If the first switch network selects the first port and the second access terminal, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the third access terminal and the fourth access terminal.

4. The antenna polarization testing device according to claim 1, characterized in that, The bridge unit includes a first bridge, a second bridge, and a third bridge. All three bridges are 90-degree 3dB bridges and each includes four signal transmission ports: a first signal port, a second signal port, a third signal port, and a fourth signal port. The first and second signal ports of the first bridge are connected to the selection terminals of the second switching network. The third and fourth signal ports of the first bridge are connected to the second signal ports of the second bridge and the first signal ports of the third bridge, respectively. The first and second signal ports of the second and third bridges are connected to loads. The third and fourth signal ports of the second and third bridges are connected to the selection terminals of the first switching network.

5. The antenna polarization testing device according to claim 4, characterized in that, When the second switching network selects the first signal port of the first bridge, the relative phases of the second bridge and the third bridge are as follows: the third and fourth signal ports of the second bridge are 90 degrees and 0 degrees respectively, and the third and fourth signal ports of the third bridge are 90 degrees and 180 degrees respectively. When the second switching network selects the second signal port of the first bridge, the relative phases of the second bridge and the third bridge are as follows: The third and fourth signal ports of the second bridge are 180 degrees and 90 degrees respectively, while the third and fourth signal ports of the third bridge are 0 degrees and 90 degrees respectively.

6. The antenna polarization testing device according to claim 4, characterized in that, When the second switching network selects the first signal port of the first bridge, if the first switching network selects the third or fourth signal port of the second bridge, then the horizontally polarized electromagnetic wave signal is transmitted through the third or fourth signal port of the second bridge; if the first switching network selects the third or fourth signal port of the third bridge, then the vertically polarized electromagnetic wave signal is transmitted through the third or fourth signal port of the third bridge. If the first switching network simultaneously selects the third signal ports of the second bridge and the third bridge, then two polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the third signal ports of the second bridge and the third bridge. If the first switching network simultaneously selects the fourth signal ports of the second bridge and the third bridge, then two polarized electromagnetic wave signals with equal amplitude and a phase difference of 180 degrees are transmitted through the fourth signal ports of the second bridge and the third bridge. If the first switching network simultaneously selects the third signal port of the second bridge and the fourth signal port of the third bridge, or simultaneously selects the fourth signal port of the second bridge and the third signal port of the third bridge, then two polarized electromagnetic wave signals with equal amplitude and 90 degrees phase difference are transmitted through the second bridge and the third bridge. When the second switching network selects the second signal port of the first bridge and the first switching network simultaneously selects the third signal port of the second bridge and the fourth signal port of the third bridge, or simultaneously selects the fourth signal port of the second bridge and the third signal port of the third bridge, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the second bridge and the third bridge.

7. The antenna polarization testing device according to claim 1, characterized in that, The first switching network is a phase-shifting network. The bridge unit includes a 90-degree 3dB bridge, which has four signal transmission ports: a first transmission port, a second transmission port, a third transmission port, and a fourth transmission port. The third and fourth transmission ports are connected to the selection terminals of the phase-shifting network, and the first and second transmission ports are connected to the selection terminals of the second switching network. The signal terminals of the phase-shifting network are connected to the first linearly polarized antenna unit and the second linearly polarized antenna unit, respectively. The second switching network selects the sum and difference ports of the 90-degree 3dB bridge according to the control signal, and the phase-shifting network selects the third transmission port and / or the fourth transmission port according to the control signal, connecting the first linearly polarized antenna unit and / or the second linearly polarized antenna unit to the 90-degree 3dB bridge and matching the phase of the signals connected to the 90-degree 3dB bridge.

8. The antenna polarization testing device according to claim 7, characterized in that, When the second switching network selects the first transmission port, and the phase shifting network selects the third or fourth transmission port, the horizontally polarized electromagnetic wave signal or the vertically polarized electromagnetic wave signal is transmitted through the third or fourth transmission port. The second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports, and matches the third and fourth transmission ports with 90-degree and 0-degree phases respectively. Two polarized electromagnetic wave signals with equal amplitude and no phase difference are transmitted through the third and fourth transmission ports. The second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports, and matches the third and fourth transmission ports with 0 degrees and 90 degrees of phase respectively. Two polarized electromagnetic wave signals with equal amplitude and 180 degrees of phase difference are transmitted through the third and fourth transmission ports. When the second switching network selects the first transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports and both are matched with 0 degrees of phase, two polarized electromagnetic wave signals with equal amplitude and 90 degrees of phase difference are transmitted through the third and fourth transmission ports. When the second switching network selects the second transmission port, and the phase shifting network simultaneously selects the third and fourth transmission ports and both are matched with a 0-degree phase, two polarized electromagnetic wave signals with equal amplitude and a phase difference of -90 degrees are transmitted through the third and fourth transmission ports.

9. A method for testing antenna polarization, characterized in that, Specifically, the following steps are included: S1. Configure the test equipment according to the test parameters and test mode of the antenna under test. The test parameters include the type and operating frequency band of the antenna under test. The test mode includes the receiving mode and the transmitting mode. The test equipment is an antenna polarization test equipment as described in any one of claims 1-8. S2. When the test mode of the antenna under test is the receiving mode, the electromagnetic wave transceiver module generates a test signal according to the type of the antenna under test and the operating frequency band and sends it to the polarization wave generation module. The polarization wave generation module converts the test signal into polarized electromagnetic wave signals with different polarization directions and radiates them to the antenna under test. The electromagnetic wave transceiver module receives the electromagnetic wave response signal after the polarized electromagnetic wave signal is converted by the antenna under test, and calculates the axial ratio and tilt angle of the antenna under test. S3. When the test mode of the antenna under test is the transmit mode, the electromagnetic wave transceiver module sends a test signal to the antenna under test, and the antenna under test converts the test signal into an electromagnetic wave signal. The polarization wave generation module converts the electromagnetic wave signal received from the antenna under test into polarized electromagnetic wave signals with different polarization directions and sends them to the electromagnetic wave transceiver module. The electromagnetic wave transceiver module calculates the axial ratio and tilt angle of the antenna under test based on the polarized electromagnetic wave signals with different polarization directions.

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