Combined parallel and sequential detection for GPS signal acquisition

A signal acquisition device comprising:

• a plurality of acquisition correlators adapted to perform an initial acquisition dwell and a series of subsequent acquisition dwells on a plurality of search cells each defined within a time/frequency uncertainty range, each acquisition dwell to detect a set of cells having the largest correlation peaks;
• and
• a plurality of independent correlators, each adapted to:
• receive a detected search cell from the acquisition correlators;
• perform an initial verification dwell on the detected search cell by comparing the peak of the detected search cell to a threshold and retaining the detected search cell only if it has a peak at least as great as the threshold;
• and
• perform at least one subsequent verification dwell on the retained search cell.

A system for tracking the location of an object using signals transmitted by GPS satellites, said system comprising:

• an antenna associated with the object for receiving GPS signals;
• and
• a signal acquisition device in operative communication with the antenna, the device including:
• a plurality of acquisition correlators adapted to perform an initial acquisition dwell and a series of subsequent acquisition dwells on a plurality of search cells each defined within a time/frequency uncertainty range, each acquisition dwell to detect a set of search cells having the largest correlation peaks;
• and
• a plurality of independent correlators, each adapted to:
• receive a detected search cell from the acquisition correlators;
• perform an initial verification dwell on the detected search cell by comparing the peak of the detected search cell to a threshold and retaining the detected search cell only if it has a peak at least as great as the threshold;
• and
• perform at least one subsequent verification dwell on the retained search cell.

A signal acquisition process comprising:

• a) performing a plurality of acquisition dwells on a plurality of search cells each defined within a time/frequency uncertainty range, each acquisition dwell to detect “x” number of search cells having the largest correlation peaks;
• b) comparing the search cells detected during the acquisition dwells and retaining “x” number of cells having the largest correlation peaks;
• and
• c) performing a verification dwell on the “x” number of search cells by comparing the peak of each search cell to a threshold and retaining only those search cells having a peak that exceeds the threshold.

A signal acquisition device comprising:

• a plurality of acquisition correlators adapted to perform acquisition dwells on a plurality of search cells each defined within a time/frequency uncertainty range to detect “x” number of search cells having the largest correlation peaks;
• a processor adapted to compare the search cells detected during the acquisition dwells and retain “x” number of search cells having the largest correlation peaks;
• and
• a plurality of independent correlators, each adapted to:
• receive a detected cell from the processor;
• perform an initial verification dwell on the detected search cell by comparing the peak of the detected cell to a threshold and retaining the detected search cell only if it has a peak at least as great as the threshold;
• and
• perform a subsequent verification dwell on the retained search cell.

A system for tracking the location of an object using signals transmitted by GPS satellites, said system comprising:

• an antenna associated with the object for receiving GPS signals;
• and
• a signal acquisition device in operative communication with the antenna, the device including:
• a plurality of acquisition correlators adapted to perform acquisition dwells on a plurality of search cells each defined within a time/frequency uncertainty range to detect “x” number of search cells having the largest correlation peaks;
• a processor adapted to compare the search cells detected during the acquisition dwells and retain “x” number of search cells having the largest correlation peaks;
• and
• a plurality of independent correlators, each adapted to:
• receive a detected search cell from the processor;
• perform an initial verification dwell on the detected search cell by comparing the peak of the detected search cell to a threshold and retaining the detected search cell only if it has a peak at least as great as the threshold;
• and
• perform a subsequent verification on the retained search cell.