Antenna performance verification system

Abstract

The utility model discloses an antenna performance verification system. The system comprises a reference antenna, a to-be-tested automobile, a signal emission assembly and a signal analyzer. The number of the signal transmitting assemblies is at least three, the signal transmitting assemblies are distributed in a circumferential array, the center point of the circumference is set as a test point, and the test point is provided with a reference antenna or a to-be-tested automobile; the to-be-tested automobile is provided with a tested antenna; and the signal analyzer is electrically connected with the reference antenna or the tested antenna. The verification system provided by the utility model fully simulates a darkroom test method, does not need to be carried out in a darkroom, can quickly detect various performances of the tested antenna, and has the advantages of high accuracy, low requirement on a test environment and greatly reduced cost compared with the prior art.

Description

Technical Field

[0001] This utility model relates to the field of antenna performance testing, and in particular to an antenna performance verification system. Background Technology

[0002] There are two main existing methods for testing vehicle antenna performance: one is to use precision instruments and equipment to collect and process high-precision data in a dark room to obtain the final result, and the other is to use human auditory organs to judge and obtain the final result.

[0003] The antenna under test is mounted on a car. For the first testing method, the car with the antenna under test needs to be placed on a turntable and rotated 360° to measure the antenna data at various angles. The data is then processed to obtain the final result. However, this method requires placing both the car and the equipment in an anechoic chamber, which requires significant space, is difficult to construct, and is costly. For the second testing method, although the cost is lower and the testing difficulty is lower, this method is highly dependent on human organs, making it prone to subjective judgment errors. Furthermore, various interference factors during the testing process can easily lead to inaccurate final results. Utility Model Content

[0004] The technical problem to be solved by this invention is to provide an antenna performance verification system that reduces the difficulty of testing while ensuring the accuracy of measurement results.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] An antenna performance verification system, characterized in that it includes a reference antenna, a vehicle under test, a signal transmitting component, and a signal analyzer;

[0007] The signal transmitting components are at least three and are distributed in a circular array, with the center point of the circle set as a test point, and a reference antenna or the vehicle under test is set at the test point.

[0008] The vehicle under test has an antenna being tested.

[0009] The signal analyzer is electrically connected to the reference antenna or the antenna under test.

[0010] Furthermore, the distance R between the signal transmitting component and the reference antenna is:

[0011] ,

[0012] Where D is the maximum length of the antenna under test, and λ is the antenna wavelength corresponding to the test frequency band.

[0013] Furthermore, the signal transmitting component includes a transmitting antenna and a signal generator;

[0014] The transmitting antenna is electrically connected to the signal generator, and the signal emitted by the transmitting antenna can be received by the signal analyzer.

[0015] Furthermore, the signal analyzer receives the signal from the reference antenna, analyzes it, and obtains the field strength E0 at the test point, where E0 ≥ 40 dBuv / m.

[0016] Furthermore, it also includes a bracket, the number of which is the sum of the number of the transmitting antenna and the reference antenna. The transmitting antenna and the reference antenna are respectively mounted on the bracket, and the heights of the transmitting antenna, the reference antenna and the antenna under test are the same.

[0017] Furthermore, the bracket includes a support member and a mounting member, the mounting member being vertically adjustable on the support member, and the mounting member being used for mounting a transmitting antenna or a reference antenna.

[0018] Furthermore, the signal generator is located on the side of the transmitting antenna away from the reference antenna.

[0019] Furthermore, it also includes network analyzers;

[0020] The network analyzer is electrically connected to the reference antenna or the antenna under test, and is used to test the resonant point of the reference antenna or the antenna under test.

[0021] Furthermore, the transmitting antenna is an FM band antenna.

[0022] Furthermore, the transmitting antenna and the signal generator are electrically connected via a coaxial cable, and / or,

[0023] The network analyzer is electrically connected to the reference antenna or the antenna under test via a coaxial cable.

[0024] The beneficial effects of this invention are as follows: Based on the testing principle and method of far-field testing, this invention sets up a reference antenna and arranges multiple signal transmitting components around this geometric center, allowing a signal analyzer to measure the radiation field around the reference antenna. The reference antenna is primarily used for debugging the transmitting components. Once the test results of the reference antenna meet expectations, it is replaced with the antenna under test, and its various performance characteristics are tested. The verification system formed by this invention fully simulates the anechoic chamber testing method without requiring a separate anechoic chamber, and can quickly verify the various performance characteristics of the antenna under test. Compared with existing technologies, it offers higher accuracy, lower requirements for the testing environment, and significantly reduced costs. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the antenna performance verification system (with the reference antenna as the geometric center) in this utility model. Figure 1 ;

[0026] Figure 2 This is a schematic diagram of the antenna performance verification system (with the antenna under test as the geometric center) in this utility model. Figure 2 .

[0027] Label Explanation:

[0028] 1. Reference antenna; 2. Signal transmitting assembly; 21. Transmitting antenna; 22. Signal generator; 3. Signal analyzer; 4. Vehicle under test; 41. Antenna under test; 5. Network analyzer; 6. Signal amplifier. Detailed Implementation

[0029] To explain in detail the technical content, objectives, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0030] Please refer to Figure 1 as well as Figure 2 An antenna performance verification system includes a reference antenna 1, a signal transmitting assembly 2, a signal analyzer 3, and a vehicle under test 4. The signal transmitting assembly 2 comprises at least three components arranged in a circular array, with the center point of the array designated as a test point. The reference antenna 1 or the vehicle under test 4 is mounted on the test point. The vehicle under test 4 has an antenna 41 under test. The signal analyzer 3 is electrically connected to the reference antenna 1 or the antenna 41 under test. A signal amplifier 6 is mounted on the vehicle under test 4.

[0031] The final measured gain G of the tested antenna 41 is calculated as follows: G = (Measured value E1 of the tested antenna 41) - (Measured value E0 of the reference antenna 1) + (Gain G0 of the reference antenna 1). Here, E1 is the field strength (dBuv / m) measured by the signal analyzer 3 when testing the tested antenna 41, E0 is the field strength (dBuv / m) measured by the signal analyzer 3 when testing the reference antenna 1, and G1 is the antenna coefficient (dB / m) set in the factory specifications of the reference antenna 1.

[0032] It is understood that this utility model, based on the testing principle and method of far-field testing, sets up a reference antenna 1 and arranges multiple signal transmitting components 2 around the reference antenna 1 as its geometric center to measure the radiation field around the reference antenna 1. The reference antenna 1 is mainly used to debug the transmitting components. When the test results of the reference antenna 1 meet expectations, the reference antenna 1 is replaced with the antenna under test 41, and the various performance characteristics of the antenna under test 41 are tested. The verification system formed by this utility model fully simulates the anechoic chamber testing method, without the need for an anechoic chamber, and can quickly verify the various performance characteristics of the antenna under test 41. Compared with the prior art, it has high accuracy, lower requirements for the testing environment, and significantly reduced costs. Among them, the signal analyzer 3 is used to test the signal strength of the reference antenna 1 and record the signal strength at different frequencies.

[0033] Specifically, a transmitting component is provided at least at the directions of 0°, 90°, 180° and 270° at the geometric center, and the distance between the signal transmitting component 2 and the reference antenna 1 is R.

[0034] In some embodiments, the distance R between the signal transmitting component 2 and the test point is:

[0035] ,

[0036] Where D is the maximum length of the antenna 41 under test, and λ is the antenna wavelength of the corresponding test frequency band. For example, when the test frequency band is the FM band, then λ is the FM antenna wavelength; when the test frequency band is the AM band, then λ is the AM antenna wavelength. The test frequency band is not limited to the above two frequency bands and can also be other broadcast antennas.

[0037] When the antenna 41 under test is mounted on the glass of the vehicle 4 under test, the value of D is the length of the vehicle 4 under test. R is the radius of the aforementioned virtual circle. The distance R between the signal transmitting component 2 and the reference antenna 1 should meet the above conditions, so that the distance between the reference antenna 1 and the signal transmitting component 2 is far enough to test the surrounding radiation field and ensure that the electromagnetic wave at the location of the reference antenna 1 is a plane wave. Preferably, the verification system should be used in an open outdoor environment without strong electromagnetic interference.

[0038] In some embodiments, the signal transmitting assembly 2 includes a transmitting antenna 21 and a signal generator 22; the transmitting antenna 21 is electrically connected to the signal generator 22, and the signal emitted by the transmitting antenna 21 can be received by the signal analyzer 3. The signal generator 22 is used to output a test signal and transmit the signal through the transmitting antenna 21, so that the signal analyzer 3 can receive the transmitted signal from the transmitting antenna 21. Preferably, the transmitting antenna 21 is an FM band antenna.

[0039] The antenna frequency bands of the antenna under test 41, reference antenna 1, and transmitting antenna 21 can be radio broadcast antenna bands (FM, AM, DAB, DTV, etc.) and communication antenna bands (3G / 4G / 5G, V2X, GNSS, Wi-Fi, or UWB, etc.). For example, in an antenna performance verification system, the performance of an FM band antenna needs to be tested. Specifically, transmitting antenna 21 transmits a signal every 4MHz from 76-108MHz, with a transmission power of 0dBm. Transmitting antennas 21 are numbered sequentially from 1# to 4# (the numbering rule is: the transmitting antenna 21 closest to the antenna under test 41 is selected as 1#; for example, when testing the rear windshield antenna, the transmitting antenna 21 located at the rear of the vehicle is 1#). During the test, the signal analyzer 3 should be in field strength receiving mode. The transmission frequency and transmission power of transmitting antenna 21 can also be adjusted according to actual needs; for example, the transmission frequency can be set to transmit once every 1-2MHz.

[0040] In some embodiments, taking the FM band as an example, the signal analyzer 3 receives the signal from the reference antenna 1, analyzes it, and obtains the field strength E0 at the test point, where E0 ≥ 40 dBuv / m. When the field strength E0 at the test point is greater than 40 dBuv / m, it can be confirmed that the field strength at the test point meets the test requirements, and a field strength E0 greater than 60 dBuv / m is optimal. It is worth noting that natural noise varies with geographical location, season, time, and frequency. For ease of calculation and international coordination, the minimum usable field strength value for the medium wave band is internationally defined as 60 dBuv / m, depending on the region (mainly latitude). The minimum usable field strength will also be different when testing the AM band or other antenna bands. The field strength E0 measured by the signal analyzer 3 = the measured value after correction of the reference antenna 1 (dBuv) + the antenna coefficient G0 of the reference antenna 1 (dB / m). The coefficient of the reference antenna 1 is known and needs to be input into the signal analyzer 3 before testing.

[0041] In some embodiments, the system further includes supports, the number of which is the sum of the number of transmitting antennas 21 and reference antennas 1. The transmitting antennas 21 and reference antennas 1 are respectively mounted on corresponding supports, and the heights of the transmitting antennas 21, reference antennas 1, and the antenna under test 41 are the same. Optionally, the height of the transmitting antenna 21 is 1m to 1.5m. Preferably, the height of the transmitting antenna 21 is 1.3m. The supports are used to stabilize the transmitting antenna 21 and to position it at the same height as the antenna under test 41, ensuring the accuracy and reliability of the test structure.

[0042] In some embodiments, the bracket includes a support member and a mounting member. The mounting member is vertically adjustable and mounted on the support member. The mounting member is used to mount the transmitting antenna 21 or the reference antenna 1 to adjust the height of the transmitting antenna 21 or the reference antenna 1. When the antenna under test 41 is mounted on the vehicle under test 4, the height of the transmitting antenna 21 and the reference antenna 1 is consistent with the height of the antenna under test 41, typically 1m-1.5m. Specifically, the mounting member passes through the support member, and a fastener is provided on the top of the support member to fix the relative position of the mounting member and the support member. After the mounting member is adjusted to a suitable height, it is fixed by the fastener to ensure stability.

[0043] In some embodiments, the signal transmitter is located on the side of the transmitting antenna 21 away from the reference antenna 1 to avoid interfering with the signal transmitted by the transmitting antenna 21.

[0044] In some embodiments, a network analyzer 5 is also included; the network analyzer 5 is electrically connected to the reference antenna 1 or the antenna under test 41, and is used to test the resonant point of the reference antenna 1 or the antenna under test 41. The network analyzer 5 is configured to analyze the standing wave (SWR) in the FM band corresponding to the antenna under test 41, and to test the resonant point of the antenna under test 41. Specifically, when the network analyzer 5 measures a resonant point in the 76-108MHz frequency band of the antenna under test 41, that is, when the measured value of the S11 parameter (which represents the input return loss of the antenna) is less than -10dB at one or more frequency points, the next step of testing can be performed. Generally speaking, the quality of the SWR can be reflected by testing the resonant point; a good SWR location corresponds to a resonant point in the measured point or the measured frequency band.

[0045] In some embodiments, the transmitting antenna 21 is electrically connected to the signal generator 22 via a low-loss coaxial cable, and / or the network analyzer 5 is electrically connected to the reference antenna 1 via a low-loss coaxial cable, in order to minimize the attenuation of long-distance signal transmission and ensure the accuracy of test results.

[0046] Embodiment 1 of this utility model is as follows:

[0047] In this embodiment, the antenna under test 41 is a vehicle antenna, which is usually integrated into the vehicle glass, such as the windshield. In other equivalent embodiments, the antenna under test 41 can be the antenna of other vehicles.

[0048] An antenna performance verification system includes a reference antenna 1, a vehicle under test 4, a signal transmitting component 2, and a signal analyzer 3. The signal transmitting component 2 consists of four components arranged in a circular array. The four signal transmitting components 2 simplify the testing system while ensuring good roundness. The center point of the circle is set as a test point, and either the reference antenna 1 or the vehicle under test 4 is mounted on the test point. The vehicle under test 4 has an antenna 41 under test. The signal analyzer 3 is electrically connected to the reference antenna 1 or the antenna 41 under test.

[0049] In this embodiment, the distance R between the signal transmitting component 2 and the reference antenna 1 is:

[0050] ,

[0051] Where D is the maximum size of the antenna 41 under test, and λ is the antenna wavelength in the FM band.

[0052] In this embodiment, the signal transmitting component 2 includes a transmitting antenna 21 and a signal generator 22; the transmitting antenna 21 is electrically connected to the signal generator 22, and the signal emitted by the transmitting antenna 21 can be received by the signal analyzer 3.

[0053] In this embodiment, the number of supports is the sum of the number of transmitting antennas 21 and reference antennas 1. The transmitting antennas 21 and reference antennas 1 are respectively mounted on the corresponding supports, and the heights of the transmitting antennas 21, reference antennas 1 and the antenna under test 41 are the same, with the height of the transmitting antenna 21 being 1.3m.

[0054] In this embodiment, the signal transmitter is located on the side of the transmitting antenna 21 away from the reference antenna 1.

[0055] In this embodiment, a network analyzer 5 is also included; the network analyzer 5 is electrically connected to the reference antenna 1 and is used to test the resonant point of the reference antenna 1.

[0056] In this embodiment, the transmitting antenna 21 and the signal generator 22 are electrically connected via a low-loss coaxial cable; the network analyzer 5 and the reference antenna 1 are electrically connected via a low-loss coaxial cable.

[0057] In this embodiment, when the signal analyzer 3 receives the signal from the reference antenna 1, the field strength of the signal analyzer 3 is equal to 60 dBμV.

[0058] Taking the FM band as an example, the working principle of this utility model is as follows:

[0059] S1: Use network analyzer 5 to test the standing wave of the FM band corresponding to the antenna under test 41. If the measured value of one or more frequency points of parameter S11 is less than -10dB, proceed to the next test.

[0060] S2: With reference antenna 1 as the geometric center, a transmitting component is set at 0°, 90°, 180° and 270° of the geometric center respectively, and the distance between reference antenna 1 and the transmitting component is R≥(2D^2) / λ;

[0061] S3: The transmitting components transmit signals sequentially in the order of 1# to 4#, and transmit signals at a frequency of once every 4MHz within the range of 76-108MHz, with a transmission power of 0dBm. The signal strength measured by the reference antenna 1 when the four antennas transmit signals is recorded by the signal analyzer 3.

[0062] S4: Replace the reference antenna 1 with the antenna under test 41, set the antenna under test 41 at the geometric center, repeat S3, and have the signal analyzer 3 record the signal strength measured by the antenna under test 41 when the four antennas transmit signals respectively.

[0063] S5: Determine whether the antenna performance is good based on the 1# transmitting antenna 21, and determine whether the directivity of the tested antenna 41 is good based on the 2#~4# transmitting antennas 21;

[0064] S6: Evaluate the tested antenna 41 whose test results are good. Evaluation criteria include, but are not limited to: 1. Clear and loud sound; 2. Clear sound; 3. Relatively clear sound with slight noise; 4. Significant noise; 5. Significant noise, unbearable, almost impossible to hear the broadcast.

[0065] In summary, the antenna performance verification system provided by this utility model uses a signal analyzer, a reference antenna, and multiple transmitting components to simulate an anechoic chamber testing method, enabling rapid and accurate performance testing of the antenna under test on a vehicle. Compared with existing technologies, it has lower execution difficulty, greater flexibility, higher accuracy, and lower cost.

[0066] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. An antenna performance verification system, characterized in that, This includes a reference antenna, the vehicle under test, signal transmitting components, and a signal analyzer; The signal transmitting components are at least three and are distributed in a circular array, with the center point of the circle set as a test point, and a reference antenna or the vehicle under test is set at the test point. The vehicle under test has an antenna being tested. The signal analyzer is electrically connected to the reference antenna or the antenna under test.

2. The antenna performance verification system according to claim 1, characterized in that, The distance R between the signal transmitting component and the test point is: ， Where D is the maximum length of the antenna under test, and λ is the antenna wavelength corresponding to the test frequency band.

3. The antenna performance verification system according to claim 1, characterized in that, The signal transmitting component includes a transmitting antenna and a signal generator; The transmitting antenna is electrically connected to the signal generator, and the signal emitted by the transmitting antenna can be received by the signal analyzer.

4. The antenna performance verification system according to claim 1, characterized in that, The signal analyzer receives the signal from the reference antenna, analyzes it, and obtains the field strength E0 at the test point, where E0 ≥ 40 dBuv / m.

5. The antenna performance verification system according to claim 3, characterized in that, It also includes a bracket, the number of which is the sum of the number of the transmitting antenna and the reference antenna. The transmitting antenna and the reference antenna are respectively mounted on the bracket, and the transmitting antenna, the reference antenna and the antenna under test are at the same height.

6. The antenna performance verification system according to claim 5, characterized in that, The bracket includes a support member and a mounting member, the mounting member being vertically adjustable on the support member, and the mounting member being used for mounting a transmitting antenna or a reference antenna.

7. The antenna performance verification system according to claim 3, characterized in that, The signal generator is located on the side of the transmitting antenna away from the reference antenna.

8. The antenna performance verification system according to claim 1, characterized in that, It also includes network analyzers; The network analyzer is electrically connected to the reference antenna or the antenna under test, and is used to test the resonant point of the reference antenna or the antenna under test.

9. The antenna performance verification system according to claim 3, characterized in that, The transmitting antenna is an FM band antenna.

10. The antenna performance verification system according to claim 8, characterized in that, The transmitting antenna and the signal generator are electrically connected via a coaxial cable, and / or, The network analyzer is electrically connected to the reference antenna or the antenna under test via a coaxial cable.

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