A field strength probe omnidirectional automatic test system

Abstract

This application discloses an automatic omnidirectional testing system for field strength probes, relating to the field of field strength probe testing. The system includes: a standard electric field generator for generating a standard electric field in the test area; a stepper-driven probe holder placed within the standard electric field; a field strength probe mounted on the stepper-driven probe holder for acquiring field strength signals; a stepper positioning control host connected to a stepper motor on the stepper-driven probe holder for driving the stepper motor to rotate the field strength probe at multiple angles; and a data acquisition and processing module connected to the stepper positioning control host for controlling the stepper positioning control host to drive the field strength probe to rotate stepwise at set angles, and calculating the omnidirectional deviation of the field strength probe based on the field strength signal and the standard electric field strength. This application enables high-precision, high-efficiency, and high-reliability automatic testing of the omnidirectionality of field strength probes.

Description

Technical Field

[0001] This application relates to the field of field strength probe testing, and in particular to an automatic omnidirectional field strength probe testing system. Background Technology

[0002] Electric field strength measurement is a fundamental and crucial task in industry, communications, national defense, environmental protection, and scientific research. With increasingly complex electromagnetic environments and the continuous expansion of operating frequency bands for electronic devices, higher demands are placed on the accuracy, efficiency, omnidirectionality, and intelligence of field strength measurements. As the core component of field strength measurement, the omnidirectional performance of the field strength probe directly determines the accuracy and reliability of the measurement results; therefore, omnidirectional testing has become an essential step in the inspection and calibration of field strength probes.

[0003] Currently, omnidirectional field strength probe testing is mainly conducted manually or semi-automatically, relying on standard electric field generating devices, manual / semi-electrically controlled probe supports, and data acquisition equipment. Low-frequency testing uses a TEM chamber to generate a standard electric field, while high-frequency testing uses a microwave anechoic chamber to radiate the field through a standard gain antenna. The testing process requires manual adjustment of the probe angle, data recording, and deviation calculation.

[0004] Existing technologies suffer from problems such as low measurement accuracy, cumbersome operation, low efficiency, and poor test repeatability. The angle deviation, inconsistent positioning, and electromagnetic interference caused by manual operation make it difficult to meet the requirements of high-precision, high-efficiency, and fully automated omnidirectional testing. Summary of the Invention

[0005] The purpose of this application is to provide an automatic testing system for the omnidirectionality of field strength probes, which can achieve high-precision, high-efficiency, and high-reliability automatic testing of the omnidirectionality of field strength probes.

[0006] To achieve the above objectives, this application provides an automatic testing system for the omnidirectionality of a field strength probe, comprising: A standard electric field generating device is used to generate a standard electric field in a test area; The stepper-driven probe bracket is placed within a standard electric field. The field strength probe, mounted on the stepper drive probe bracket, is used to collect field strength signals; The stepper positioning control host is connected to the stepper motor on the stepper drive probe bracket and is used to drive the stepper motor on the stepper drive probe bracket to rotate the field strength probe at multiple angles. The data acquisition and processing module is connected to the stepping positioning control host and is used to control the stepping positioning control host to drive the field strength probe to rotate step by step at a set angle, and to calculate the omnidirectional deviation of the field strength probe based on the field strength signal and the standard electric field strength.

[0007] According to the specific embodiments provided in this application, this application has the following technical effects: This application utilizes a stepper positioning control host to automatically drive the stepper probe bracket, causing the field strength probe to rotate at multiple angles. This replaces manual adjustment of the probe angle, avoiding angle deviations and positioning inconsistencies caused by manual operation, and significantly improving the measurement accuracy and repeatability of the field strength probe's omnidirectional testing. The system achieves fully automated testing through a unified control module for rotation and data processing, eliminating the need for manual recording and calculation, greatly simplifying the operation process and improving testing efficiency. The entire system can complete omnidirectional signal acquisition and deviation calculation within a preset standard electric field, meeting the requirements for high-precision, high-efficiency, and fully automated omnidirectional testing of field strength probes, and adapting to increasingly complex electromagnetic environments and wide-band measurement requirements. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] Figure 1 This is a schematic diagram of the functional modules of an automatic field strength probe omnidirectional testing system provided in an embodiment of this application. Detailed Implementation

[0010] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0011] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0012] In one exemplary embodiment, such as Figure 1 As shown, an automatic omnidirectional testing system for field strength probes is provided, including: a standard electric field generating device 1, a stepper-driven probe bracket 2, a field strength probe 3, a stepper positioning control host 4, and a data acquisition and processing module 5.

[0013] Standard electric field generating device 1: Used to generate a uniform, stable, and known-intensity standard electric field within a specific test area. Depending on the operating frequency of the field strength probe, standard electric field generating device 1 includes a low-frequency calibration device and a high-frequency calibration device.

[0014] Stepper drive probe bracket 2: Placed in a standard electric field, it serves as the support and motion mechanism for the field strength probe 3. It can drive the field strength probe 3 to rotate at high precision in multiple angles, ensuring that the field strength probe 3 can receive field strength signals from different directions.

[0015] Field strength probe 3: mounted on stepper drive probe bracket 2, used to sense field strength signals in space.

[0016] Stepper positioning control host 4: connected to stepper drive probe bracket 2, drives the motor in stepper drive probe bracket 2 to move, thereby controlling the field strength probe 3 to rotate at multiple angles.

[0017] Data acquisition and processing module 5: It is connected to the stepping positioning control host 4 and the field strength probe 3 respectively. It is used to control the stepping positioning control host 4 to drive the field strength probe 3 to rotate step by step at a set angle, and calculate the omnidirectional deviation of the field strength probe 3 based on the field strength signal and the standard electric field strength to complete the test.

[0018] Furthermore, the low-frequency calibration device operates in low-frequency test mode and is suitable for testing field strength probes with operating frequencies from 10kHz to 1000MHz. The low-frequency calibration device mainly includes a Transverse Electromagnetic Wave (TEM) chamber. The TEM chamber is a closed metal cavity, connected at one end to an RF power source and at the other end to a 50Ω load, forming a uniform and stable transverse electromagnetic wave field inside, serving as the low-frequency standard electric field for testing. The stepper-driven probe holder 2 and the stepper positioning control host 4 are located inside the transverse electromagnetic wave chamber.

[0019] Furthermore, the high-frequency calibration device operates in high-frequency test mode and is suitable for testing field strength probes with operating frequencies ranging from 1 GHz to 40 GHz. The device mainly consists of a microwave anechoic chamber, a standard gain antenna, and an antenna support.

[0020] Microwave anechoic chamber: Provides a test space free from reflection and external interference.

[0021] Standard gain antenna: installed in a microwave anechoic chamber and connected to an RF power source to radiate a stable high-frequency standard electric field.

[0022] Antenna bracket: Used to fix and adjust the position (vertical height, horizontal position and pitch angle) of the standard gain antenna, ensuring that the standard gain antenna is at the same height and aligned with the field strength probe 3, so that the high-frequency standard electric field can uniformly cover the test area of ​​the field strength probe 3.

[0023] Furthermore, in high-frequency testing mode, the system also includes a separate probe bracket to support the stepper-driven probe bracket 2. The probe bracket includes a circular base, a vertical rod, and a clamp.

[0024] A circular base is placed on the floor of the microwave anechoic chamber, and a vertical rod is set on the circular base. The clamp is mounted on the vertical rod, and the stepper drive probe bracket 2 is fixed to the clamp by non-conductive screws. This non-conductive connection method avoids the disturbance of the high-frequency electric field by the metal screws. The clamp can slide up and down along the vertical rod to adjust the height, ensuring that the field strength probe 3 on the stepper drive probe bracket 2 can receive a uniform high-frequency standard electric field.

[0025] Furthermore, the stepper drive probe bracket 2 includes a bracket body, a stepper motor, a grounding shield wire, and a microwave absorbing material.

[0026] The support body is made of solid non-metallic materials (such as engineering plastics, polytetrafluoroethylene, etc.) to avoid the distortion of electric field distribution caused by metallic materials.

[0027] Stepper motor: Built inside the bracket body, it drives the field strength probe 3 to rotate around its own axis through a mechanical transmission structure.

[0028] Absorbing material: The stepper motor is coated with absorbing material. Since the stepper motor generates electromagnetic radiation when it is working, the absorbing material can effectively absorb this radiation energy and prevent it from interfering with the weak signal acquisition of the field strength probe.

[0029] Grounding shielding wire: The bracket body is connected to a grounding shielding wire and reliably grounded. This shielding wire is used to shield external electromagnetic interference and prevent internally leaked electromagnetic signals from radiating outwards.

[0030] Furthermore, the stepper positioning control host 4 is battery powered. This design eliminates ground loop interference introduced by the mains power, reducing the impact of power supply noise on the test system at its source. The stepper positioning control host 4 and the stepper drive probe bracket 2 are connected via four signal lines to control the rotation direction and power supply of the stepper motor.

[0031] Furthermore, the field strength probe 3 is fixedly mounted on the stepper drive probe bracket 2 via a fixed probe base. The fixed probe base is also made of non-conductive material and is secured with non-conductive screws to ensure electrical isolation.

[0032] Furthermore, the data acquisition and processing module includes: an optical power supply and a host computer.

[0033] The optical power supply, powered by 220V, connects to the field strength probe 3 via optical fiber. It powers the probe and receives the field strength signal output from it. The optical fiber, being non-conductive and non-magnetic, completely eliminates the ground loop, achieving electrical isolation and significantly improving the signal-to-noise ratio. The optical power supply transmits the field strength signal to the host computer via USB, RS232, or GPIB.

[0034] The host computer is connected to the stepping positioning control host 4 and the optical power supply respectively. It is used to control the stepping positioning control host 4 to drive the field strength probe 3 to rotate step by step at a set angle, and to calculate the omnidirectional deviation of the field strength probe based on the field strength signal and the standard electric field strength.

[0035] The host computer sends control commands to the stepper positioning control host 4. The stepper positioning control host 4 controls the stepper motor in the stepper drive probe bracket 2 according to the control commands, thereby driving the field strength probe 3 to rotate step by step at a set angle.

[0036] The specific steps for automatically testing the omnidirectional field strength probe using the above system are as follows: Step 1: Determine the operating frequency of the field strength probe and select the corresponding calibration method to avoid inaccurate test data due to frequency, which could damage the field strength probe.

[0037] Step 2: Select the corresponding standard electric field generation method according to the operating frequency and set up the test environment.

[0038] If the operating frequency is within the range of 10kHz to 1000MHz, select the low-frequency test mode and set up the test environment. Specific operation: Connect a 50Ω load to one end of the TEM chamber and an RF power source to the other end. Ignite RF power into the TEM chamber and calculate the strength of the standard electric field inside the TEM chamber by measuring the RF power. Place the stepper positioning control host and the stepper drive probe bracket simultaneously into the TEM chamber. Position the stepper drive probe bracket at the center between the PEM Cell base plate and the core plate of the TEM chamber, ensuring the field strength probe is in a uniform standard electric field. Mount the field strength probe onto the stepper drive probe bracket using the probe base and non-conductive screws. Connect the optical power supply to the field strength probe via an extended optical fiber. The host computer establishes communication with both the optical power supply and the stepper positioning control host via USB cables. The core function of the stepper positioning control host is to drive the field strength probe on the stepper drive probe bracket to rotate around its axis. The core function of the optical power supply is to power the field strength probe and transmit the data measured by the field strength probe to the host computer.

[0039] If the operating frequency is within the range of 1GHz to 40GHz, select the high-frequency test mode and set up the high-frequency test environment. Specific procedures: Use a microwave anechoic chamber, fix the standard gain antenna inside the chamber using an antenna bracket, connect an RF power source, and inject RF power into the standard gain antenna. Calculate the standard electric field strength value radiated by the standard gain antenna by measuring the RF power. Fix the field strength probe to the stepper drive probe bracket using the probe base and non-conductive screws, and then fix the stepper drive probe bracket to the probe bracket using non-conductive screws. Adjust the antenna bracket and the stepper drive probe bracket to ensure that the standard gain antenna and the field strength probe are at the same height, and that the field strength probe is aligned along the central axis of the standard gain antenna aperture. Simultaneously adjust the horizontal distance between them to ensure that the field strength probe can receive a uniform high-frequency electric field.

[0040] Step 3: Adjust the probe angle to acquire omnidirectional signals.

[0041] The host computer sends commands to the stepper positioning control host to drive the stepper drive probe bracket, controlling the field strength probe to rotate one revolution around its own axis at the same angle. This rotation is performed sequentially according to the program-set angles, ensuring the field strength probe can receive electric field signals from different horizontal directions in sequence. During each pause, the electrical signal output by the field strength probe is read via a photoelectric power supply, and the signal value corresponding to that angle is recorded, ensuring that field strength response data from the probe in all directions within a 360° range is acquired.

[0042] Step 4: Data processing, calculate omnidirectional bias.

[0043] After the optical power supply receives the field strength signals from all angles, the host computer sends a power-off command to the stepper positioning control host to control the stepper motor in the stepper drive probe bracket to power off, reducing the interference generated by the stepper motor itself. Then, the field strength probe transmits the electrical signal values ​​of all angles collected to the optical power supply through the optical fiber connection. The optical power supply then transmits the data to the host computer via USB. The host computer software converts the electrical signal values ​​into corresponding field strength signals according to a preset algorithm, and then compares them with the strength of the standard electric field calculated in step 2 to calculate the field strength deviation at each angle. Finally, the omnidirectional deviation of the field strength probe is obtained, completing the entire omnidirectional test process.

[0044] This application has the following advantages: Advantage 1: Strong anti-interference ability and higher testing accuracy.

[0045] Existing technologies mostly employ single anti-interference methods, resulting in limited effectiveness. This system innovatively adopts a five-layer anti-interference design: battery power supply, grounding shielding wire, absorbing material, fiber optic transmission, and motor power-off protection. This comprehensive approach mitigates electromagnetic interference across four stages: power supply, motor, transmission, and processing. In particular, the design of attaching absorbing material around the stepper motor and automatically cutting off power after data acquisition is rarely seen in existing technologies. This minimizes the impact of interference on test data, ensuring the accuracy and authenticity of the electric field signal received by the field strength probe. This, in turn, improves the accuracy of omnidirectional deviation calculation. Compared to existing technologies, test errors are significantly reduced, and test results are more reliable.

[0046] Advantage 2: Automated angle adjustment, making omnidirectional data acquisition more accurate and efficient.

[0047] Existing technologies rely on manual adjustment of the probe angle, which suffers from problems such as uneven angles, positioning deviations, and low efficiency. This system, through the linkage between the stepper positioning control host and the stepper-driven probe bracket, enables the field strength probe to automatically rotate 360° around its axis. The angle stepping is uniform and the positioning is accurate, ensuring that field strength response data in all directions of the field strength probe are collected without any angle omissions. At the same time, automated adjustment replaces manual operation, greatly reducing human intervention and solving the drawbacks of manual operation in existing technologies.

[0048] Advantage 3: Automated data processing with low error rate and strong closed-loop performance.

[0049] Existing technologies separate data acquisition and processing, resulting in significant manual intervention and high error rates. This system automates the entire process from signal acquisition to data recording and deviation calculation. The optical power supply automatically reads the signal, and the host computer automatically records the data and calculates the deviation, eliminating the need for manual recording and calculation. This not only greatly simplifies the testing process but also completely avoids errors caused by manual operation, forming a complete closed loop from test environment setup to result output. Both testing efficiency and result accuracy are significantly improved.

[0050] Advantage 4: The test environment is accurately positioned and highly stable.

[0051] In existing high-frequency testing, the alignment of the standard gain antenna and the field strength probe relies on manual methods, which are inaccurate and susceptible to external interference. This system ensures that the standard gain antenna and the field strength probe are aligned in height and direction through coordinated adjustment of the antenna bracket and probe bracket. Furthermore, high-frequency testing is conducted in a microwave anechoic chamber to avoid external interference, ensuring that the electric field received by the field strength probe is uniform and stable. Low-frequency testing utilizes a closed TEM chamber, which generates a uniform and stable low-frequency electric field, further improving the stability of the testing environment. Compared to existing technologies, this system offers better consistency in the testing environment and stronger repeatability of test results.

[0052] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0053] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An automatic testing system for the omnidirectionality of an electric field probe, characterized in that, include: A standard electric field generating device is used to generate a standard electric field in a test area; The stepper-driven probe bracket is placed within a standard electric field. The field strength probe, mounted on the stepper drive probe bracket, is used to collect field strength signals; The stepper positioning control host is connected to the stepper motor on the stepper drive probe bracket and is used to drive the stepper motor on the stepper drive probe bracket to rotate the field strength probe at multiple angles. The data acquisition and processing module is connected to the stepping positioning control host and is used to control the stepping positioning control host to drive the field strength probe to rotate step by step at a set angle, and to calculate the omnidirectional deviation of the field strength probe based on the field strength signal and the standard electric field strength.

2. The automatic field strength probe omnidirectional testing system according to claim 1, characterized in that, The standard electric field generating device includes a low-frequency calibration device and a high-frequency calibration device. The low-frequency calibration device operates in low-frequency test mode and is suitable for testing field strength probes with operating frequencies of 10KHz to 1000MHz. The high-frequency calibration device operates in high-frequency test mode and is suitable for testing field strength probes with operating frequencies of 1GHz to 40GHz.

3. The automatic field strength probe omnidirectional testing system according to claim 2, characterized in that, The low-frequency calibration device includes a transverse electromagnetic wave chamber. In low-frequency test mode, the stepper drive probe bracket and the stepper positioning control host are placed inside the transverse electromagnetic wave chamber.

4. The automatic field strength probe omnidirectional testing system according to claim 2, characterized in that, The high-frequency calibration device includes a microwave anechoic chamber, a standard gain antenna, and an antenna support. The antenna support is placed inside the microwave anechoic chamber, and the standard gain antenna is mounted on the antenna support.

5. The automatic field strength probe omnidirectional testing system according to claim 2, characterized in that, In high-frequency testing mode, the system also includes a probe holder; The probe bracket includes a circular base, a vertical rod, and a clamp; the circular base is placed on the floor of the microwave anechoic chamber, the vertical rod is vertically mounted on the circular base, and the clamp is mounted on the vertical rod; the stepper-driven probe bracket is fixed to the clamp by non-conductive screws.

6. The automatic field strength probe omnidirectional testing system according to claim 1, characterized in that, The stepper drive probe bracket includes a bracket body, a stepper motor, a grounding shield wire, and absorbing material. A stepper motor, located inside the bracket body, is used to drive the field strength probe to rotate at multiple angles; The absorbing material is coated on the outer surface of the stepper motor to absorb the electromagnetic radiation generated when the stepper motor is working. The grounding shield wire is connected to the bracket body and grounded to shield against external electromagnetic interference and leaked electromagnetic signals.

7. The automatic field strength probe omnidirectional testing system according to claim 1, characterized in that, The field strength probe is fixedly mounted on the stepper drive probe bracket via a fixed probe base.

8. The automatic field strength probe omnidirectional testing system according to claim 1, characterized in that, The stepper positioning control unit is battery powered.

9. The automatic field strength probe omnidirectional testing system according to claim 1, characterized in that, The data acquisition and processing module includes: The optical power supply is connected to the field strength probe via optical fiber. It is used to power the field strength probe and receive the field strength signal output by the field strength probe. The host computer is connected to the stepping positioning control host and the optical power supply, respectively. It is used to control the stepping positioning control host to drive the field strength probe to rotate step by step at a set angle, and to calculate the omnidirectional deviation of the field strength probe based on the field strength signal and the standard electric field strength.

10. The automatic field strength probe omnidirectional testing system according to claim 9, characterized in that, After the optical power supply receives the field strength signals from all angles, the host computer sends a power-off command to the stepper positioning control host to control the stepper motor in the stepper drive probe bracket to cut off the power.

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