Development Of Input And Output Impedance Measurement System For Telemetry Interface

With the rapid development of the electronic technology,single space-borne electronic products show the characteristics of integration,integration,complexity and high precision,which make the number of the interface of the single machine products become more and more.The impedance measurement frequency range,range,accuracy requirements unceasing enhancement,and the impedance measurement method and the related technology is witnessing profound changes.With digital signal processing and band-pass sampling technology as the core digital impedance measurement method has become a hot research topic in the field of modern impedance measurement and the development tendency.This topic fully understood the impedance measurement technology,analyzed the advantages and disadvantages of the existing test equipment," Development of input and output impedance measurement system for telemetry interface " has been developed by digital signal processing.This system greatly reduces the test time of the electronic products telemetry interface impedance,and realizes the transformation from manual testing to automated testing,improves the testing efficiency,testing security and accuracy.Test system consists of one control board,two relay array board,one Agilent U2741 A multi-meter module and a USB HUB.The main control board is the core control part,includes all interfaces and PC communication.Relay array board achieves 202 program-controlled switch array,and realizes node selection function.Multi-meter module implements the built-in function measurement.In addition,designed the mechanical mechanism,procured the required electronic components,and completed the construction of the hardware platform.The host computer software of the test system was compiled with C++6.0 Visual.Software can read test Excel spreadsheets and automatic parse the test form,It can realize the input impedance,output impedance test the switch funct ion,and has out-of-tolerance remind function.At the same time,it can realize the remote control oscilloscope state and real-time data acquisition,display and save functions.Finally,the input and output impedance test equipment is debugged,and the test experiment is done,and the test results are analyzed.System experiment results show that voltage acquisition accuracy is better than + 10 m V,impedance and the testing accuracy is better than 0.5%,the other test precision of the measured parameters in the test system are meet the project requirements.This verified the correctness of the test method and program.At the same time,the system is running well,and the performance is stable.