Abstract
GPS wireless sensor network, which is a displacement monitoring system using a low cost L1 GPS receiver as a sensor of wireless sensor network, has been developed by the authors. Since the cost per a single observation point can be decreased, the dense sensor deployment is applicable to the displacement monitoring under a construction site or the estimation of disaster distribution in a large earthquake.
In this research, quasi-static displacement is monitored by using the prototype system developed by the authors. The experimental results show that the accuracy is about 1 cm after applying Kalman filter to the positioning reuslts. In case of estimating a sudden displacement, integer ambiguities should be determeined as an usual GPS positioning analysis. A data mask method and a weight estimation method using SNR (Signal to Noise ratio) of raw carrier phase data are introduced to the anaylsis. A redeterminataion algorithm for fixing integer ambiguities is also developed by the authors. The Fix rate of integer ambiguities is improved by introducing these technique to the GPS positioning analysis.
