The present invention is a method and apparatus for generating a scaled
correlation that is based on an estimate of the arrival time of a
synchronization point in a received RF signal relative to a sampling
clock, which is used to sample the received RF signal after down
conversion. The scaled correlation may be used to validate the estimate
of the arrival time of the synchronization point and, in certain
embodiments of the present invention, may be used to update the estimate
of the arrival times for subsequent synchronization points. Using the
scaled correlation may provide arrival time estimates with a finer
resolution and accuracy than the period of the sampling clock. Such
arrival time estimates are important for timing-based applications, such
as GPS receivers or navigation receivers.