Active RFID (active electronic tag) is an electronic tag type divided according to different power supply modes of electronic tags. It usually supports long-distance identification. Due to the internal battery, compared with passive and semi passive RFID, active electronic tag has certain advantages in reliability and compatibility due to its low transmission power, long communication distance and large amount of data transmission. It is widely used in vehicle identification management, port freight management, military material and dangerous goods tracking, medical personnel and equipment management and other applications. Etc in our common intelligent transportation does not charge for parking, and parking lot vehicle management is a typical case.