Patent ID: 7928829
Filing Date: 2011-04-19
Classification: B60R,G07C

Abstract:
1. A method for controlling access to a vehicle, comprising the following steps: sending a periodic request signal from the vehicle to a mobile ID transmitter; in response to receiving the periodic request signal from the vehicle, the mobile ID transmitter transmitting a response signal including an identifier to the vehicle; the vehicle authorizing the mobile ID transmitter based on the identifier received from mobile ID transmitter; in response to authorizing the mobile ID transmitter, the vehicle sending an authentication request to the mobile ID transmitter; in response to receiving the authentication request from the vehicle, the mobile ID transmitter transmitting an authentication response including an authentication code to the vehicle; the vehicle confirming the authentication code received from mobile ID transmitter, and in response, sending an authentication signal to the mobile ID transmitter, with which signal the ID transmitter is authorized to unlock the vehicle; the mobile ID transmitter determining the distance from the valid mobile ID transmitter to the vehicle; the mobile ID transmitter determining whether the determined distance is below a predetermined first proximity distance; in response to determining that the determined distance is below the predetermined first proximity distance, the mobile ID transmitter transmitting an unlock signal from the valid authorized mobile ID transmitter to the vehicle, such that the process for unlocking the vehicle includes at least the three message exchanges of (a) the periodic request signal from the vehicle answered by the response signal from the mobile ID transmitter, (b) the authentication request from the vehicle answered by the authentication response from the mobile ID transmitter, and (c) the authentication signal from the vehicle followed by the unlock signal from the mobile ID transmitter.