QUICK AND ACCURATE SPECIFICATION OF GEOGRAPHICAL POSITION FOR CELLULAR TELEPHONE USING GPS SATELLITE SYSTEM

摘要

PROBLEM TO BE SOLVED: To reduce the capturing time required to access a GPS signal used to determine the positional coodinates of an user in relation to a wireless communication system. SOLUTION: A wireless communication network transmits all GPS ID of a satellite visible in an area and predicted values for Doppler and signal intensity concerning a visible GPS satellite to a user terminal 20 in each spot beam or a cell. The user terminal 20 has a GPS terminal to receive C/A codes from the GPS satellite 11, 14-16. The user terminal 20 quickly captures the GPS C/A signal for all visible GPS satellites 11, 14-16 by using GPS supporting data transmitted therefrom. The user terminal 20 returns GPS C/A code measured values to the wireless network to be processed together with other GPS data. In this way, the need for executing all calculating function required to specify a position at the user terminal 20 is eliminated.