Abstract: A Global Positioning System (GPS) receiver employs variable spacing of Doppler offset bins and code offset bins when acquiring a P(Y) code, to improve signal acquisition characteristics with respect to a search region having a plurality of Doppler offset bins and code offset bins. The receiver includes an acquisition module in which an input signal representative of a received P(Y) code is received and applied to a first programmable rate mixer. An output of the first programmable rate mixer is applied to a combiner, which selectively combines samples of the input signal based on a control input to dynamically determine the spacing of the code offset bins. An output of the combiner is normalized and applied to a correlation unit, which generates correlation measures of the received P(Y) code and a locally generated P(Y) code. A signal representative of the correlation measures is applied separately to each of a set of programmable rate mixers and mixed with separate mixing signals.

Abstract: A Global Positioning System (GPS) receiver includes multiple correlation segments that can operate in parallel. Each correlation segment has a separate set of accumulators associated with it, embodied in random access memory (RAM). In each of the correlation segments, correlation data associated with an input code and a reference code are generated. The multiple correlation segments are cross-coupled, so that correlation data generated in each correlation segment are added to correlation data generated in each other correlation segment. The combined correlation data in each correlation segment are stored in the accumulators of each corresponding correlation segment, such that the accumulators of only one correlation segment are accessed at a time, reducing power consumption resulting from accessing RAM.