Method and apparatus for reducing the time required to acquire a GPS signal

摘要

A method of correlating a digital communications signal is described. In an example, a window is defined equal to a portion of an epoch of the digital communication signal. The digital communication signal is then correlated across the window. A determination is made as to whether a correlation peak results from the correlating. Timing parameters are then established for receiving additional digital communication signals in response to presence of the correlation peak.

主权项

1. An apparatus for correlating a communication signal received from a first satellite, comprising:
a microcontroller configured to select a window equal to a portion of an epoch of the communication signal; and a processing channel comprising a plurality of correlators each configured to correlate the communication signal with a reference code shifted relative to the communication signal by a different amount of time within the selected window to identify a correlation peak, wherein the microcontroller is further configured to establish a timing parameter, based on a location of the selected window within the epoch, for reducing a search range for an additional communication signal from a second satellite.