Patent ID: 8692713

Claim:
A receiving device comprising: receiving circuitry configured to receive a signal from each of a plurality of satellites in a global positioning system; frequency conversion circuitry configured to convert a frequency of the signal of each of the plurality of satellites received by the receiving circuitry into respective predetermined intermediate frequency signals; synchronization acquisition circuitry configured to carry out synchronization acquisition to detect phase of a spread code of each of the plurality of predetermined intermediate frequency signals converted by the frequency conversion circuitry, and to detect a carrier frequency of each of the plurality of predetermined intermediate frequency signals; synchronization holding circuitry configured to assign and set, for each of the plurality of satellites, the phase of the spread code detected by the synchronization acquisition circuitry and the carrier frequency detected by the synchronization acquisition circuitry to each of a plurality of channels independently provided in a corresponding manner to each of the plurality of the satellites, to hold, for each of the plurality of satellites, the set phase of the spread code and the set carrier frequency, and to demodulate a message included in each of the plurality of predetermined intermediate frequency signals; and control circuitry configured to execute operation control including position calculation of each of the plurality of satellites using the message demodulated by the synchronization holding circuitry, wherein the synchronization holding circuitry includes a plurality of spreading code generation circuitry portions each configured to generate a spreading code synchronized with the spread code of a corresponding one of the plurality of predetermined intermediate frequency signals, and to refer to a counter operating with a temperature-compensated clock oscillator oscillating at a predetermined frequency, and wherein, during a sleep period in which a positioning operation is not carried out, the synchronization holding circuitry causes only the plurality of spreading code generation circuitry portions and the counter to operate.