US Patent 7916021 Smart entry system and method

A smart entry system and method includes at least one actuating device for operation of at least two vehicle functions, an on-board transmitter for sending request signals to a portable device, and an on-board receiver for receiving an identification signal from the portable device. The on-board transmitter sends a first request signal within a first search field when the at least one actuating device is subjected to a first actuating operation for initiating a first vehicle function. A second request signal is sent within a second search field when the at least one actuating device is subjected to a second actuating operation for initiating a second vehicle function. The first search field varies relative to the second search field.