Remote radio frequency calibration system and method

Abstract

The invention provides a remote radio frequency signal calibration system and method. A coaxial cable, a radio frequency optical transmission module, an optical fiber, a radio frequency optical receiving module and a coaxial cable are sequentially linked to form a radio frequency transmission link; measuring the link loss of the radio frequency transmission link as power compensation data; the input end of the radio frequency transmission link is connected to a to-be-tested instrument of the test system, and the output end is connected to a measurement standard; communication between the upper computer and a metering standard is realized by using a network cable and a switch in a metering laboratory; the optical fiber transceiver is used for realizing long-distance communication between the upper computer and the instrument to be tested through an optical fiber; and the instrument to be tested is calibrated through automatic calibration software of the upper computer. Under the condition of not changing the measurement standard and the position of the instrument to be measured, remote automatic calibration is realized, the efficiency is high, and the speed is high.

Description

Technical Field

[0001] The present application relates to the technical field of radio metrology calibration, and in particular to a long-distance radio frequency calibration system and method. Background Art

[0002] Since the components and parts of electronic measuring instruments have different degrees of sensitivity to temperature, humidity, atmospheric pressure, power supply voltage, vibration, electromagnetic interference and other environments, even if it is the same radio measuring instrument, when it is in a different environment, its measurement accuracy may be completely different. Therefore, radio measurement standards need to be calibrated in the metrology laboratory. On the other hand, with the rapid development of radio measuring instruments integration and systematization, more and more radio measuring instruments are fixed in the form of test systems.

[0003] There are usually two ways to perform periodic metrological calibration on instruments in a test system. One is to dismantle the instruments and move them to a metrology laboratory for calibration. However, repeated disassembly and assembly of instruments in the test system will affect the stability and reliability of the test system. The other is to move the metrological standards to the test system for metrological calibration. However, since the metrological standards have high environmental requirements, it is difficult to meet the metrological laboratory requirements on site.

[0004] The above two instrument calibration methods have certain limitations and shortcomings, and it is difficult to adapt to the development trend of instrument use. Therefore, it has become a trend in the development of calibration technology to build a method to achieve remote calibration without changing the measurement standard and the state of the instrument being measured. Summary of the invention

[0005] The present application provides a long-distance radio frequency calibration method, which can be used to solve the technical problems of inaccurate calibration methods and high environmental requirements in the prior art.

[0006] The present application provides a long-distance radio frequency signal calibration system, the system comprising an electromagnetic compatibility darkroom and a metrology laboratory;

[0007] Among them, the electromagnetic compatibility darkroom includes the instrument under test, the radio frequency optical transmission module and the optical fiber transceiver;

[0008] The metrology laboratory includes metrology standards, radio frequency optical receiving modules, optical fiber transceivers, routers and host computers.

[0009] The radio frequency optical transmission module is connected to the radio frequency optical fiber receiving module through an optical fiber; the input end of the radio frequency optical fiber receiving module is connected to the measurement standard;

[0010] The signal transmission path starting from the network communication interface of the instrument under test in the electromagnetic compatibility chamber is fiber optic transceiver, optical fiber, fiber optic transceiver, router in sequence; finally, it is connected to the host computer through a network cable.

[0011] The method provided in this application is implemented using the system provided in this application. The method provided in this application includes:

[0012] Step 1: After inputting the reference signal into the RF optical transmission module of the electromagnetic compatibility darkroom, the signal is transmitted to the RF optical fiber receiving module of the metrology laboratory through the optical fiber, and the power loss of the RF transmission link is measured using the metrology standard as the power compensation data;

[0013] Step 2: Connect the RF output port of the instrument under test in the electromagnetic compatibility darkroom to the input end of the RF optical transmission module, convert the RF signal into an optical signal, and then transmit the measured signal to the input end of the RF optical receiving module in the metrology laboratory over a long distance through an optical fiber. The RF optical receiving module converts the optical signal into a RF signal and then connects it to the measurement standard, thus forming a RF signal transmission link;

[0014] Step 3: The network communication interface of the instrument under test in the electromagnetic compatibility chamber is connected to the fiber optic transceiver, and the communication signal is connected to the fiber optic transceiver in the metrology laboratory through optical fiber; the communication network in the metrology laboratory includes network cables, host computers, metrology standards, fiber optic transceivers, and routers.

[0015] Step 4: The upper computer automatic calibration software inputs the SCPI standard instrument control command into the instrument under test through the communication network, controls the instrument under test to output the RF signal to be tested, and after the RF signal to be tested is input into the measurement standard through the RF signal transmission link, the automatic calibration software controls the measurement standard to measure the power of the measured signal, calculates the power parameters of the instrument under test after superimposing the power compensation data, and automatically issues a calibration report after completing the calibration of the instrument under test.

[0016] The present invention provides a method for long-distance radio frequency calibration, which can realize long-distance automatic calibration without changing the position of the measurement standard and the instrument to be tested, with high efficiency and high speed. The present application establishes a radio frequency signal transmission path from the test system to the metrology laboratory. Since radio frequency optical transmission modulation and demodulation are directional, a radio frequency transmission link from the metrology laboratory to the test system can also be established. A fiber optic transceiver is used to perform long-distance communication between a host computer and the instrument to be tested through optical fiber. In the metrology laboratory, network cables and switches are used to communicate between the host computer and the measurement standard. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A system schematic diagram of a long-distance radio frequency calibration system according to the present invention;

[0018] Figure 2 The present invention provides a flow chart of a long-distance radio frequency calibration method. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present application clearer, the implementation methods of the present application will be further described in detail below with reference to the accompanying drawings.

[0020] The following first introduces the embodiments of the present application in conjunction with the accompanying drawings.

[0021] In this embodiment, the signal generator is installed in the test system as a radio frequency signal generating device, and the measurement receiver is installed in the metrology laboratory as a signal generator measurement standard. The remote calibration of the signal generator is achieved through the following steps.

[0022] Step 1: The RF input terminal is connected to the RF optical transmission module via a coaxial cable.

[0023] Step 2: Use the RF optical transmission module to modulate the RF signal into an optical signal, and transmit the optical signal over long distances through optical fiber.

[0024] Step 3: At the receiving end, the modulated optical signal is restored and demodulated into a radio frequency signal using a radio frequency optical receiving module.

[0025] Step 4: Measure the link loss of the radio frequency transmission link as power compensation data.

[0026] Step 5: Connect the input end of the RF transmission link to the signal generator and the output end to the measurement receiver to achieve long-distance transmission of the RF signal.

[0027] Step 6: Use network cables and switches in the metrology laboratory to achieve communication between the host computer and the metrology standard.

[0028] Step 7: Use the optical fiber transceiver to achieve long-distance communication between the host computer and the instrument under test through optical fiber.

[0029] Step 8: The host computer automatic calibration software combines the power compensation data to control the measurement receiver and the signal generator to automatically complete the remote calibration.

[0030] Step 9: Issue a calibration report.

[0031] The above-described embodiments of the present application do not constitute a limitation on the protection scope of the present application.

Claims

1. A long-distance radio frequency signal calibration system, characterized in that: The system includes: an electromagnetic compatibility darkroom and a metrology laboratory; Among them, the electromagnetic compatibility darkroom includes the instrument under test, the radio frequency optical transmission module and the optical fiber transceiver; The metrology laboratory includes metrology standards, radio frequency optical receiving modules, optical fiber transceivers, routers and host computers. The radio frequency optical transmission module is connected to the radio frequency optical fiber receiving module through an optical fiber; the input end of the radio frequency optical fiber receiving module is connected to the measurement standard; The signal transmission path starting from the network communication interface of the instrument under test in the electromagnetic compatibility chamber is fiber optic transceiver, optical fiber, fiber optic transceiver, router in sequence; finally, it is connected to the host computer through a network cable.

2. A long-distance radio frequency signal calibration method, characterized in that: The method is implemented using the system provided by claim 1, and the method comprises: Step 1: After inputting the reference signal into the RF optical transmission module of the electromagnetic compatibility darkroom, the signal is transmitted to the RF optical fiber receiving module of the metrology laboratory through the optical fiber, and the power loss of the RF transmission link is measured using the metrology standard as the power compensation data; Step 2: Connect the RF output port of the instrument under test in the electromagnetic compatibility darkroom to the input end of the RF optical transmission module, convert the RF signal into an optical signal, and then transmit the measured signal to the input end of the RF optical receiving module in the metrology laboratory over a long distance through an optical fiber. The RF optical receiving module converts the optical signal into a RF signal and then connects it to the measurement standard, thus forming a RF signal transmission link; Step 3: The network communication interface of the instrument under test in the electromagnetic compatibility darkroom is connected to the optical fiber transceiver, and the communication signal is connected to the optical fiber transceiver in the metrology laboratory through the optical fiber; the communication network in the metrology laboratory includes network cables, host computers, metrology standards, optical fiber transceivers, and routers; Step 4: The upper computer automatic calibration software inputs the SCPI standard instrument control command into the instrument under test through the communication network, controls the instrument under test to output the RF signal to be tested, and after the RF signal to be tested is input into the measurement standard through the RF signal transmission link, the automatic calibration software controls the measurement standard to measure the power of the measured signal, calculates the power parameters of the instrument under test after superimposing the power compensation data, and automatically issues a calibration report after completing the calibration of the instrument under test.

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