An improved code acquisition scheme for faster acquisition of GPS "coarse acquisition"
(C/A) codes leads to faster detection of GPS signals, and thereby a wireless terminal
may determine its position in a shorter period of time. The scheme is a combination
of a frequency-domain and time-domain code acquisition techniques. The scheme utilizes
a frequency-domain code acquisition technique to detect one GPS signal and to create
a precise timing reference at the wireless terminal, and then utilizes time-domain
code acquisition techniques to detect other GPS signals from the same satellite
or other satellites faster. The scheme has the advantage of being able to be used
for any wireless communications system without the requirement of maintaining a
precise timing reference in the wireless terminals, and without the requirement
of heavy computational resources that are usually needed in systems that utilize
frequency-domain code acquisition techniques.
