Patent ID: 8547253
Filing Date: 2013-10-01
Classification: G01S,H01Q

Abstract:
1. A method of indicating a proximity value representative of the distance between a key fob system and a vehicle system, comprising: transmitting an N plurality of locate signals from the key fob, each of the N plurality of locate signals having a different signal strength; performing RSSI measurements for the N plurality of locate signals received by the vehicle system; determining a proximity value by the vehicle system based on the N plurality of locate signals received; determining by the vehicle system the power level optimal for distinguishing proximity using the signal strength of the N received locate signals; transmitting from the vehicle system the transmit power level for the next key fob transmission along with the RSSI value and the proximity value; displaying a proximity value on the key based on RSSI measurements; setting the key fob system transmission power signal strengths of an N+1 plurality of locate signals to that received from the vehicle system and a level greater than that received from the vehicle system; and transmitting the N+1 plurality of locate signals from the key fob system, each of the N+1 plurality of locate signals having a different signal strength.