The active RF system uses the built-in power supply in the tag to form an active active area around the tag. The tag actively acquires RF at a low or high position and a long distance and transmits it to the reader. In passive systems, the RF activation tag is issued by the reader, and the passive system requires a strong RF signal, so the reader and tag can work when they are close together. Semi-active systems use internal energy to monitor the surrounding environment, but also require the reader to signal the RF activation tag. The difference between semi-active and passive is that there is internal energy in the semi-automatic system. The tag can perform other functions, such as monitoring the temperature of the surrounding environment, oscillating conditions, etc., and can also extend the range of RF activity.