Method of acquiring error correction value of reference frequency, terminal device, program, and recording medium

• Main Authors: YANO, KOICHIRO, MAEZAWA, HIDEKAZU
• Format: Patent
• Language: English; French; German
• Published: 19.03.2008
• Subjects: ANALOGOUS ARRANGEMENTS USING OTHER WAVES; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES; MEASURING; PHYSICS; RADIO DIRECTION-FINDING; RADIO NAVIGATION; TESTING

A terminal device receives satellite signals from a plurality of satellite positioning system (SPS) satellites and locates a position. The terminal device periodically calculates a first drift df1 of a local oscillator using a reference frequency Hr, calculates a search range of the satellite signal using the first drift dfl, calculates a second drift df2 of the local oscillator using a reception frequency of the satellite signal, calculates a reference frequency error ² which is an error of the reference frequency by calculating a difference between the first drift df1 and the second drift df2, and calculates an error correction value ²av of the reference frequency by subjecting a plurality of the reference frequency errors ² to a statistical process.