| 摘要 |
PROBLEM TO BE SOLVED: To determine doppler data from received satellite almanac data, to provide a mobile unit for calculating positional information of a satellite including at least one pseudo range from the doppler data, and to provide a method and mobile unit for calibrating the frequency of a GPS local oscillator. SOLUTION: The mobile unit receives satellite almanac data of a plurality of satellites in view of the mobile unit through a cellular communication link from a cell site, and determines doppler data from the satellite almanac data. A local oscillator is calibrated using a precision carrier frequency signal such that the output of the local oscillator used to acquire GPS signals is modified by a reference signal generated from the precision carrier frequency signal. COPYRIGHT: (C)2010,JPO&INPIT |
