A method of despreading a plurality of GPS spread spectrum signals received by
a GPS receiver (24) is disclosed together with a GPS receiver (24)
and a mobile communications device (MS1) (especially a mobile cellular telephone)
for the same. The method comprises the steps of acquiring a first GPS signal from
the stored samples; obtaining frequency information relating to variations in the
frequency of the first acquired signal as measured by the GPS receiver; and using
the frequency information to acquire a second GPS signal. The frequency information
may be used to acquire the second GPS signal in the course of a single dwell and
may also, for a digital GPS receiver, relate to variations in the frequency of
the first acquired signal present in stored samples.