| 摘要 |
PROBLEM TO BE SOLVED: To enhance the capacity of security and improve operational reliability and extend the service life of a battery in a keyless entry system which is mainly employed for cars. SOLUTION: A first coded signal, which is predetermined as a specified value, and a second coded signal which is changed every time when it is transmitted, are synthesized with a first synthetic signal generator 19. The first coded signal and a third coded signal, which is set to a specified value, are synthesized with a second synthetic signal generation area 20, thereby transmitting either synthetic signal by way of a transmission means 22. An extraction means 23 extracts the first coded signal from a synthetic signal received with a receiving means 7 where the rest of the extracted signals are compared with the stored second and third coded signals with comparison means 29 and 31, thereby determining the output signal, responding with either result of the comparison means 29 and 31. |
