A method to identify the noise from LED light bulbs by comparing the time domain characteristics of impulsive electromagnetic noise and light emission

Abstract

A measurement method by comparing the time domain characteristics of impulsive electromagnetic noise and light emission was proposed to identify the noise from LED light bulbs which generated electromagnetic interference. To identify their noise, the waveform of the electromagnetic noise and light intensity from the LED lamp was measured simultaneously using an oscilloscope. This method identified the noise by means of property that the LED light bulb had a product-specific switching pattern corresponding to the power supply, both of radiation of impulsive electromagnetic noise and amplitude modulation of light emission from the LED light bulb occurs in synchronization with it. The validity of the proposed method was experimentally demonstrated.