GNSS R Delay Doppler Map Simulation Based on the 2004 Sumatra Andaman Tsunami Event
A new method for simulating Global Navigation Satellite System Reflectometry (GNSS R) delay Doppler maps (DDMs) of a tsunami dominant sea surface is presented. In this method, the bistatic scattering Z V model, the sea surface mean square slope model of Cox and Munk, and the tsunami induced wind perturbation model are employed. The feasibility of the Cox and Munk model under a tsunami scenario is examined by comparing the Cox and Munk model based scattering coefficient with the Jason 1 measurement. A good consistency between these two results is obtained with a correlation coefficient of 0.93. After confirming the applicability of the Cox and Munk model for a tsunami dominated sea, this study provides the simulations of the scattering coefficient distribution and the corresponding DDMs of a fixed region of interest before and during the tsunami. In the final analysis, by subtracting the simulation results that are free of tsunami from those with presence of tsunami, the tsunami induced variations in scattering coefficients and DDMs can be clearly observed. As a result, the tsunami passage can be readily interpreted.
J. Sensors