| 摘要 |
PROBLEM TO BE SOLVED: To prevent unauthorized use by a third party by encrypting data (pressure detecting signals) transmitted from a transmitter of a tire air pressure detecting device. SOLUTION: A transmitter 2 is mounted to each of wheels, detects air pressure of a tire of the wheel by a sensing part 21, encrypts detection signals by an encryption rule according to an encryption instructing signal N at an encryption part 22b, stores them in a transmission frame, and transmits them via an antenna 23. A receiver 3 is mounted to a vehicle body side, receives the transmission frame encrypted by an antenna 31, decrypts it according to the encryption instructing signal N at a decryption part 32b, and finds a tire air pressure from the data decrypted at a control part 32c. At this time, the encryption instructing signal N is transmitted to the transmitter 2 from the receiver 3, and is commonly used by both of them. COPYRIGHT: (C)2006,JPO&NCIPI |
