Tropospheric delays in ground-based GNSS reflectometry – Assessment of ad-hoc models against ray-tracing simulations

Global Positioning System (GPS) multipath reflectometry (GPS-R) has recently emerged as coastal sea level altimetry technique. GPS-MR is based on the simultaneous reception of direct and reflecting satellite signals, exploiting the signal-to-noise ratio measurements. Atmosphere affects the GPS signals proportionally to the height of the antenna and results to underestimation of the tidal amplitudes. Over the last decade, atmospheric error (or delay) was accounted for in GPS-MR to varying degrees. Two simple-to-use formulations have emerged based on different properties of refraction. The project explores the capabilities and limits of these formulations and proposes a new comprehensive method to account for the atmospheric delay. Additionally, employing a ray-tracing procedure estimates the delay rigorously and compares it to the results of the existing and proposed formulations. To gain insight, decomposition of the delay to its components takes place. Finally, the dependence of the error on satellite elevation angle, station altitude, and antenna height is assessed. The expected outcomes will aid in understanding of the atmospheric error in GPS-R and offer an improved modelling of the latter. “TO BE CONT’D”

Faculty Supervisor:

Marcelo Santos

Student:

Partner:

Universidade Federal do Rio Grande do Sul

Discipline:

Engineering

Sector:

Environmental Science and Technology; Technology

University:

University of New Brunswick

Program: