The suppression technique of electromagnetic interference of motor vehicle

On abroad, electromagnetic interference(EMI) from motor vehicles and their effect on broadcast radio and television were studies as early as 1944. Their original effect was significantly reduced by the early 1960s. Today, the use of advanced electronically controlled various vehicles are widespread. Most of the vehicular functions are now controlled by microprocessors that send electrical instructions to other devices which operate the engine and transmission as well as the implements the machine was designed to use. Ignition noise and vehicular microprocessor-controlled system noise are interfering with mobile communication services and devices such as computers. In China, EMI from the vehicle was begun to study in 1970s. Without enforcing rules and regulation, the vehicular electrmognetic emission is now interfering mobile communication, broadcast radio and other devices. This paper describes the vehicular EMI and the suppression technique for automobile EMI studied by the author on the communication vehicles.