A robust test apparatus for electromagnetic compatibility testing and improvement utilizing a network analyzer

A simple but rigorous test apparatus is presented and validated experimentally, which provides not only an accurate and effective electromagnetic (EM) immunity testing system, but also accurately characterizes the EM immunity spectrum of an equipment under test. The apparatus utilizes the features of a network analyzer (NA) along with directional couplers and a power meter. It also provides accurate EM interference environment measurement without a field strength meter. This proposed test apparatus provides not only an accurate and effective EM immunity testing system, but also accurately characterizes the EM immunity spectrum of a device under test. An immunity test for a digital transmission system was conducted to verify the effectiveness of this test apparatus. The failure frequencies of this equipment under test (EUT) are detected within the measured immunity spectrum.