Abstract
In this paper, an electromagnetic interference (EMI) noise measurement technique based on wavelet analysis is proposed to measure the electromagnetic radiation generated by the device. The technique uses the time-frequency localization characteristic of the wavelet transform, based on the threshold function. The filtering method divides the test signal by frequency filtering so that it can measure the electromagnetic interference of the equipment in the open field or with noise interference. Simulation and experimental results show that the technology can eliminate or attenuate noise better in the frequency range of 30 Hz ~ 1000 MHz。