A system and method is provided for tuning a Global Positioning System (GPS) antenna matching circuit in a portable wireless communications device. The method includes accepting a first matching circuit tuning value, measuring satellite vehicle (SV) carrier-to-noise ratio (C/N) associated with the first tuning value and a first search time interval, measuring the SV C/N associated with a next tuning value, and selecting the tuning value associated with the highest SV C/N to tune the matching circuit. In one aspect, the method further includes comparing the SV C/N to a first minimum threshold. If the first tuning value SV C/N exceeds the first minimum threshold, then the method measures the SV C/N associated with the next tuning value. Otherwise, a default tuning value can be selected to tune the matching circuit.