| The principal error source in the GPS technology is a delay experienced by the GPS signal in propagating through the electrically neutral atmosphere, usually referred to as a tropospheric delay. This delay is normally calculated in the zenith direction, and is referred to as a zenith tropospheric delay. The delay consists of a zenith hydrostatic delay, which can be modeled accurately using surface barometric measurements, and a zenith wet delay, which cannot be modeled from surface barometric measurements and depends on atmospheric water vapor. In this research presented here, the approach for the production of zenith wet delays from GPS observations is demonstrated. Slant wet delays are recovered for each epoch to all satellites in view assuming that the atmosphere is inhomogeneous. Experiments are conducted to determine the optimal processing parameters for estimation of tropospheric delay parameters such as elevation cutoff angle, batch processing interval, and baseline length. (Abstract shortened by UMI.)... |
