Patent ID: 7609202

Claim:
A relative measurement method for forming a relative measurement network for performing a relative measurement between predetermined stations by receiving radio waves from satellites by a reference station and a plurality of mobile stations, and measuring a reference relative displacement, which is a relative displacement of each mobile station viewed from the reference station, wherein at least one of said mobile stations is disposed so as to exceed a base line limit length that allows relative measurement with the reference station, and a space between predetermined mobile stations is set to be a base line limit length that allows relative measurement or set to be less than the base line limit length, the relative measurement method comprising: a reference relative displacement computing step of computing a reference relative displacement between the reference station and the predetermined mobile station; an inter-mobile station relative displacement computing step of computing an inter-mobile station relative displacement, which is a relative displacement between said predetermined stations; and a conversion step of converting the inter-mobile station relative displacement determined in said inter-mobile station relative displacement computing step into the reference relative displacement based on a reference displacement of said reference station, wherein a relative vector indicating a displacement of the mobile station from the reference station is separated into a long cycle fluctuation component, which does not depend on a fluctuation of the mobile station, and a short cycle fluctuation component, which depends on the fluctuation of the mobile station, and the short cycle fluctuation component is represented by each x, y and z axis component of a unit vector from the reference station to the satellite, and carrier phases between at least three satellites and each receiver are measured, and at the same time, this measurement data is passed through a band pass filter, and a short cycle phase component corresponding to the short cycle fluctuation component of the relative vector is extracted, and a least three inter-receiver single differences or inter-receiver and inter-satellite double differences between each receiver and each satellite are determined for this short cycle phase component, and based on at least three single differences or double differences, each axis component of the short cycle fluctuation component of the relative vector is computed, and thereby, the relative displacement is measured.