Patent ID: 7269511

Claim:
A GPS receiver, comprising: a radio frequency system receiving GPS signals from GPS satellites and providing digitized signals of a complex format derived from the GPS signals, wherein the GPS signal from each satellite comprises a spread spectrum modulated signal encoding a data signal, each bit of the data signal spanning a predetermined data epoch; a digital memory including a plurality of buffers for storing the digitized signals, each buffer having a predetermined size to hold digitized signals received over a time period exceeding the predetermined epoch of the data signal, the digital memory organized such that, at any given time, the digitized signals in a first one of the buffers is made available for retrieval, while the digitized signals from the radio frequency system is received into a second one of the buffers; and a digital processor coupled to the digital memory, wherein the digital processor processes the digitized signals retrieved from the digital memory to provide a de-spreaded digitized signal, and wherein the digital processor further comprises data detection circuitry configured to decode the data signal from the de-spreaded over successive data epochs.