US Patent 7173957 Efficient epoch processing in multichannel global positioning system signal receiver

One embodiment of the present invention includes a first memory, an address counter, and an adder. The first memory having KN locations stores K sums of mixer samples during an epoch interval. The mixer samples are generated at a first clock frequency from a mixer for N channels corresponding to N satellites in a global positioning system (GPS) receiver. The address counter generates an address modulo-KN corresponding to a first location in the memory at the first clock frequency. The adder adds one of the mixer samples to contents of the first location to generate a sum. The sum is written into the first location.