Fast Kalman Processing of Carrier-Phase Signals from Global Navigation Satellite Systems for Water Vapor Tomography
Lange, A. A.
Finnish Meteorological Institute

Information on orbits and clocks of the satellites of Global Navigation Satellite Systems (GNSS) are obtained in Near Real-Time (NRT) from global and/or local computing centres. The GNSS signals are received from local Geodetic networks for precise real-time estimation of all involved calibration parameters by using the Helmert-Wolf blocking (HWb) method. The carrier-phase measurements of the signals will then be used for evaluating operationally the 3-dimensional distribution of Water Vapor (3WV) of the troposphere and the Total Electron Content (TEC) of the stratosphere. Very large moving data-windows of the carrier-phases and meteorological data are processed for maintaining Kalman’s observability condition. Optimal physical and mathematical modeling is used in order to satisfy Kalman’s controllability condition that can then be monitored by estimating error variances by using the Minimum Norm Quadratic Unbiased Estimation (MINQUE) method.