A telecommunications system and method for rapid start-up of a Global
Position System (GPS) receiver integrated with a mobile terminal is
disclosed. The location of a reference GPS receiver associated with a
Base Transceiver Station (BTS) within the cell that the mobile terminal
is currently located is used as the local position estimate for that
mobile terminal. The GSM TDMA frame numbers are first correlated with the
GPS clock signal. Optionally, this correlation is adjusted using the
adaptive frame alignment mechanism. This local position estimate is used
to ascertain the location of the GPS receiver. The correlation data is
then sent to the GPS-capable mobile terminal through the Short Messaging
Service (SMS) cell broadcast facility or the Broadcast Control Channel
(BCCH) facility of the GSM network to enable the built-in GPS receiver to
calculate its position relatively quickly.