VEHICLE PASSIVE ENTRY DEVICE, AND RANGING METHOD FOR VEHICLE PASSIVE ENTRY DEVICE

摘要

Provided is a passive entry device 10 used in a vehicle 50. The passive entry device 10 is provided with: a transmission unit 13 that outputs a transmission signal of a first frequency band modulated by a transmission data signal; a receiving unit 14 that receives, as a reception signal, a signal of a second frequency band output from a key device in synchronization with the transmission signal; and a control unit 12 that forms, into sinusoidal signals, the transmission data signal and a reception data signal obtained by modulating the reception signal, that uses the transmission data signal and the reception data signal which have been formed into sinusoidal signals to respectively generate a first analysis signal and a second analysis signal, that calculates a phase difference using the first analysis signal and the second analysis signal, and that measures the distance between the key device and the vehicle.