Estimation of Total Electron Content and Instrumental Biases of Low Latitude Global Positioning System Stations Using Kalman Filter

Abstract

Listen

Translate article

In order to achieve the required navigation accuracy for satellite based augmentation system (SBAS) applications, the ionospheric total electron content (TEC) must be accurately estimated. However, measurements of TEC from the Global Positioning System (GPS) observables are corrupted by instrumental delay biases of satellites and receiver, measurement noise and multipath errors. In this investigation, an algorithm based on the Kalman filter is developed for the estimation of TEC and instrumental biases, using single station data in contrast to multi-station technique reported elsewhere. The initial state of receiver bias in the Kalman filter is chosen using a modified fitted receiver bias (FRB) method. The estimated instrumental biases for several equatorial and low latitude stations in the International GNSS Service (IGS) and GPS Aided Geo Augmented Navigation (GAGAN) network show significant improvement.