Modelling of Atmospheric Propagation Delays on Single Frequency GPS Signals

Abstract

The quality of satellite radio wave measurements is a function of a number of factors, including, atmospheric propagation delays. Through the application of more modern systems and mathematical models, it has become possible to achieve a clear exposition of systematic ways to tackle various atmospheric effects to satellite measurements.As the solar activity reached its maximum around 1990, The ionospheric propagation delay on GPS satellite signals will become more problematic. To meat the challenge of high accuracy satellite geodesy of today, atmospheric propagation delays should effectively be modelled.For single frequency users of GPS, who can not implement the dual frequency ionospheric compensation algorithm, mathematical models that account for the effects of atmospheric propagation delays were discussed. Four single frequency models were applied to minimize the effects of ionospheric propagation delay on GPS pseudo-range measurements. The models reduced the effect of ionospheric propagation delay to a level of about 30% to 43% depending on the model adopted. The efficiencies and limitations of these models were outlined. Several other techniques accounting for the effects of ionospheric delays on satellite observations were mentioned.