PASSIVE ENTRY/PASSIVE START SYSTEMS IMPLEMENTING CARRIER PHASE BASED RANGING WITH MUSIC STYLE EIGENVALUE DECOMPOSITION FOR DISTANCE DETERMINATIONS

摘要

An access system for a vehicle is provided. The access system includes antennas and an access module. The antennas are configured to each receive a signal transmitted from a portable access device to the vehicle. The signal is transmitted on a 2.4 gigahertz frequency. The access module is configured to: downconvert the received signal to generate an in-phase signal and a quadrature phase signal; perform carrier phase based ranging including implementing a music algorithm to (i) determine a distance between the portable access device and the vehicle, and (ii) determine angles of arrival of the received signal as received at the antennas; determine a location of the portable access device relative to the vehicle based on the distance and the angles of arrival; and permit access to the vehicle based on the location.