A GPS receiver includes a digital signal processor (DSP) configured to receive a carrier-modulated signal and to provide an adaptive GPS search engine operative to search the carrier-modulated signal for GPS signals over a variable number of carrier timing hypotheses. A mobile terminal includes a mobile communications transceiver, a GPS receiver, and a common frequency source that provides a common frequency reference signal for the mobile communications transceiver and the GPS receiver of the mobile terminal. The common frequency source includes an automatic frequency control (AFC) circuit operative to adjust a frequency of the common frequency reference signal responsive to interaction of the mobile communications transceiver and a wireless communications system. The GPS receiver is configured to define a carrier timing search range thereof to accommodate the automatic adjustment of the frequency of the common frequency reference signal.