초록 ▼

A positioning system is disclosed in which a rate of change .DELTA..DELTA.f in a Doppler shift .DELTA.f of the radio wave transmitted from a GPS satellite is detected in order to determine whether or not an extraordinary radio wave as caused by a multi-path or the like is being received, and a GPS s

A positioning system is disclosed in which a rate of change .DELTA..DELTA.f in a Doppler shift .DELTA.f of the radio wave transmitted from a GPS satellite is detected in order to determine whether or not an extraordinary radio wave as caused by a multi-path or the like is being received, and a GPS satellite from which an extraordinary radio wave is received is excluded from a group of GPS satellites which are utilized in a positioning calculation. A difference .DELTA.f between a signal frequency f0 transmitted from a GPS satellite and a signal frequency fR receiver is calculated, and a rate of change .DELTA..DELTA.f in the difference .DELTA.f is also calculated. The position of a receiver is calculated on the basis of information transmitted from a plurality of GPS satellites for which the rate of change .DELTA..DELTA.f is equal to or less than a first threshold value, or .DELTA..DELTA.f.ltoreq.30 Hz/s, and the azimuth of a traveling direction of the receiver is calculated on the basis of information transmitted from a plurality of GPS satellites for which the rate of change .DELTA..DELTA.f is equal to or less than a second smaller threshold value or .DELTA..DELTA.f.ltoreq.15 Hz/s.

대표청구항 ▼

[ What is claimed is:] [1.] A positioning system utilizing GPS satellites comprisingreceiving means for receiving information from a plurality of GPS satellites which transmit their respective orbital information and timing information;deviation calculation means for calculating a difference .DELTA.

[ What is claimed is:] [1.] A positioning system utilizing GPS satellites comprisingreceiving means for receiving information from a plurality of GPS satellites which transmit their respective orbital information and timing information;deviation calculation means for calculating a difference .DELTA.f between a signal frequency transmitted by one of the GPS satellites and a signal frequency received by the receiving means;variation calculation means for obtaining a rate of change .DELTA..DELTA.f in the difference .DELTA.f;and positioning calculation means for determining the position of the receiving means on the basis of information received by the receiving means from a plurality of GPS satellites for which the rate of change .DELTA..DELTA.f remains within a preselected range.