Trimble Navigation Limited

Peter Griffioen

Michael Timo Allison

Nicholas C Talbot

A real-time kinematic system includes base and rover GPS units connected by a data link. The rover unit is typically moved to points of interest during a survey while the base remains over a fixed, and known location. An initialization testing program of the present invention is mounted on a personal computer platform that forces in the rover a loss of signal tracking, thus simulating losses in signal reception caused by obstructions of the satellite signals. A complete initialization is forced to occur. The test program uninitializes the RTK solution by causing a loss of integer ambiguities resolution by forcing a loss of lock on one or more satellites. The test program then monitors the subsequent initialization process, e.g., the time needed to search for phase ambiguity candidates, discovering the prevalent satellite geometry, determination of whether the correct ambiguity candidate was found, finding the ratio of the second best to best solution variances of the ambiguity candidates in the list throughout the candidate propagation process or similar statistical test, computing the RMS error of the solution at the time that initialization was declared and after initialization, and calculating the baseline vector between the rover and base at the time of initialization and after initialization. All such statistical parameters are logged and used in post and real-time analyses of the initialization algorithm.

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Clayton, Australia

Peter Griffioen