Abstract: Disclosed are dual frequency GPS receivers using single frequency sequencing and methods of using the same to track both first global positioning signals at a first frequency and second global positioning signals at a second frequency. Both of the first global positioning signals and the second global positioning signals are received with a multi-frequency antenna or multiple antennas of different frequencies. The first global positioning signals and the second global positioning signals are separated and converted into first and second translated global positioning signals, respectively, having an intermediate frequency or frequencies. Frequency sequencing is controlled to selectively alternately couple the first and second translated global positioning signals one at a time to the channels of the digital signal processor for use in navigation solution determination.

Abstract: A system for processing signals by utilizing a tracking loop that contains two or more detectors that operate simultaneously in order to detect a frequency shift in the locally generated reference signal. A correction can then be transmitted to the tracking loop filter to minimize the effect of the detected frequency shift. In this manner lock can be maintained without the expenditures associated with the use of temperature controlled or compensated oscillators.