Patent ID: 7903026

Claim:
A positioning apparatus with a plurality of channels for scanning or tracking satellite signals, the positioning apparatus comprising: a first signal processor that carries out demodulation processing on a first signal transmitted from a satellite; a second signal processor that carries out demodulation processing on a second signal of a different frequency band or spreading scheme from the first signal; a positioner that calculates a distance from the positioning apparatus to the satellite based on results of the demodulation processings on the first signal and the second signal and carries out a positioning arithmetic operation; an electric field intensity comparer that measures an electric field intensity difference between the first signal and the second signal transmitted from the same satellite, based on results of the demodulation processings in the first signal processor and the second signal processor; an electric field intensity storage that stores the electric field intensity difference; and a controller that controls operations of channels in the first signal processor and channels in the second signal processor, based on electric field intensity information in the electric field intensity storing storage, wherein, between the first signal processor and the second signal processor, the controller operates channels for a higher electric field intensity preferentially, and when received power for a signal of the higher electric field intensity is at least equal to a predetermined value, the controller stops an operation of channels for a signal of a lower electric field intensity.