基于虚拟仪器的电磁干扰近场测试系统设计

Design of EMI Near-Field Test System Based on Virtual Instrument

摘要:

针对传统电磁干扰测试存在的环境要求苛刻、操作复杂及费用昂贵等问题,设计了一套基于虚拟仪器的电磁干扰近场测试系统;以近场探头和频谱仪组成系统硬件主体构架；运用LabWindows/CVI平台的交互式界面设计实现测试项目统一管理,通过VISA技术和NI-DAQmx完成频谱仪的控制和数据采集模块的设计;进行验证测试时,以3 kHz分辨率带宽的精度,成功排查出130 MHz处的辐射干扰;系统可满足非标准测试的需求,提高测试效率,并且开发周期短,兼容性强,具有一定的实用性与推广价值。

Abstract:

Considering the harsh requirements for test environment, complexity of the opration and expensive cost of traditional EMI test, an EMI near-field test system is designed based on virtual instrument. The main hardware architecture is composed of near-field probe and spectrum analyzer. The system uses the design of interactive interface on LabWindows/CVI to realize the unified management of test project, and also accomplishes the control of spectrum analyzer and design of data acquisition module respectively by VISA and NI-DAQmx. With the 3 kHz RBW, system detected the radiated interference of 130 MHz successfully in verification test. System can meet the requirements of non-standard EMI test and improve the test efficiency with the superiority of short development cycle and strong compatibility. The technology and methods adopted in the system are practical and worthy of further promotion. 