GPS Time Series Land Slide Monitoring using A Weighted Extended Kalman Filtering with a DIA Procedure

RTK GPS has become a global utility in engineering survey activities. RTK GPS offers an efficient means of providing near instantaneous positions by employing differential GPS positioning whereby users can obtain sub-centimetre/millimetre level position in real time. In RTK GPS all algorithms using code information only are limited to range accuracy of about 0.5-1.0 metres due to code noise. However, range measurement using carrier phase information on the other hand is limited to only 0.5-3.0 millimetres by noise. Thus the use of carrier phase measurements in high precision positioning has become indispensable. Yet in order to use the carrier phase measurements in an urban canyon environment, the user has a couple of positioning errors to deal with. Using double differencing procedure, this research work uses an exponentially weighted Extended Kalman Filter (EWEKF) with the integration of detection, identification, adaptation (DIA) method as an attempt to remove/isolate the effects of errors such as the multipath, outliers and receiver noise on GPS signals during transmission. The end result shows an improved coordinates solution.