Operation method and robbery prevention system of on vehicle robbery prevention system

摘要

(57) Abstract Sending and receiving unit (1) and the carry-along possible mark generator (4) transmits those signals at the same carrier frequency. Furthermore in this case, the transmit data of the signal which from sending and receiving unit (1) and the mark generator (4) is forwarded is overlapped inside the specified range. Because of this wiretap of the signal becomes difficult.