Global positioning satellite receiver for portable terminals has data acquisition unit which acquires data corresponding to intermediate frequency at which signal-to-noise ratio is more than threshold

摘要

A clock generation unit (19) generates standard clock at which global positioning satellite (GPS) signals are transmitted and received at radio frequency. A GPS receiver (30) mixes radio frequency with local oscillating frequency to obtain intermediate frequency which is scanned within predetermined ranges of frequency bands. The intermediate frequency at which signal-to-noise ratio is more than threshold value is determined and corresponding GPS data is acquired by an acquisition unit (21). The clock generation unit (19) generates standard clock at which global positioning satellite (GPS) signals are transmitted at radio frequency. The GPS receiver mixes radio frequency at which GPS signal is received, with local oscillating frequency to generate intermediate frequency. The frequency band existing near Doppler frequency of satellite and frequency band at which the standard clock changes from standard value is determined. The generated intermediate frequency is scanned within determined ranges of frequency bands and the signal-to-noise ratio of received GPS signal is calculated. The intermediate frequency at which signal-to-noise ratio is more than threshold value is detected and corresponding GPS data is acquired by the data acquisition unit (21). An Independent claim is also included for portable terminal.