| 摘要 |
<p>For determining in real time displacements of an object, radio signals are received (S1) from multiple satellites of a positioning system in one receiver, fixed to the object. Determined respectively at successive epochs are single differences (A) indicative of carrier phase differences between carrier signals received from defined pairs of the satellites. Time series of the single differences are stored. For at least one epoch following the current epoch, determined are predicted single differences (C) indicative of carrier phase differences expected between carrier signals received from the defined pairs of the satellites, based on the time series of the carrier phase differences. Based on the single differences of the current epoch and the predicted single differences, determined is a displacement vector (D) indicative of a displacement of the object. Thereby, the carrier phase observations of a single receiver can be filtered such that rapid movements and/or deformations of an object in the range of a few millimetres can be detected and measured in real time, while avoiding error modelling based on estimated parameters such as precise satellites orbits, tropospheric and ionospheric models, phase centre offset variation, multipath effects, clock errors etc.</p> |
