Michael F Mckenney

US Patent:

7092429, Aug 15, 2006

Filed:

Sep 26, 2002

Appl. No.:

10/256258

Inventors:

Michael F. McKenney - Anaheim CA, US

Assignee:

Interstate Electronics Corporation - Anaheim CA

International Classification:

H04B 1/69
H04B 1/707
H04B 1/713

US Classification:

375132, 375343, 375367, 708403, 708404, 708405, 708422

Abstract:

A multi-pass frequency hop timing acquisition correlator that produces a more accurate time estimate from the fast acquisition frequency hop signal is disclosed. The time estimate produced by the multi-pass acquisition correlator is more accurate than the hop estimate produced by single-pass fast acquisition correlators. The multi-pass frequency hop timing acquisition correlator uses a time estimate generated by a previous pass through the multi-pass frequency hop timing acquisition correlator as a starting point for computing a new, more accurate, time estimate. Thus, the second pass through the multi-pass frequency hop timing acquisition correlator produces a time estimate that is relatively more accurate than the time estimate produced by the first pass. The more accurate time estimate produced by the multi-pass acquisition correlator reduces the hardware and time needed by the direct acquisition process to acquire the M-code. In one embodiment, the multiple-pass frequency-hop correlator on the second or third pass provides microsecond-level timing from a GPS M-code fast acquisition frequency hop signal in a jamming environment.