Tropospheric Wet Refractivity Tomography Based on the BeiDou Satellite System

摘要

This paper presents a novel approach for assessing the precision of the wet refractivity field using BDS(BeiDou navigation satellite system) simulations only, GPS, and BDS+GPS for the Shenzhen and Hongkong GNSS network. The simulations are carried out by adding artificial noise to a real observation dataset. Instead of using the δ and σ parameters computed from slant wet delay, as in previous studies, we employ the Bias and RMS parameters, computed from the tomography results of total voxels, in order to obtain a more direct and comprehensive evaluation of the precision of the refractivity field determination. The results show that:(1) the precision of tropospheric wet refractivity estimated using BDS alone(only 9 satellites used) is basically comparable to that of GPS;(2) BDS+GPS(as of current operation) may not be able to significantly improve the data's spatial density for the application of refractivity tomography; and(3) any slight increase in the precision of refractivity tomography, particularly in the lower atmosphere, bears great significance for any applications dependent on the Chinese operational meteorological service.