| 摘要 |
PROBLEM TO BE SOLVED: To provide a positioning method for use in a GPS receiver, enabling positioning calculations without demodulating Z counts (time data). SOLUTION: This positioning method includes demodulating almost two-word data in the received navigation data during hot start, detecting the leading bit position of a parity bit in the two words through the demodulation, detecting the leading bit position of the word containing the parity bit whose leading bit position has been detected, determining measurement time at the leading bit position of the detected word by use of a built-in timepiece having an accuracy of less than±0.3 seconds, and achieving positioning by use of the determined measurement time of the built-in timepiece in place of the time derived from Z counts involved in the navigation data.
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