Verfahren zur Kommunikation zwischen einer Karte und einem Kraftfahrzeug

摘要

A communication method between a badge and a vehicle whereby a low range transmitter associated with the vehicle transmits a low frequency signal towards the badge which replies by sending a RF signal of longer range towards the vehicle. A receiver of the badge designed to receive a RF signal is placed in standby mode in accordance with a predetermined rhythm and a transmitter associated with the vehicle sends during a standby phase of the badge a RF signal whereto the badge replies with a RF signal. The invention is applicable to hands-free systems.