A Precision Evaluation Method for Inter-satellite Link Measurement of Ka Band Based on SLR

Abstract

Improving the autonomous operation ability has become a main goal of satellite navigation system in the new century. The technology to apply inter-satellite link (ISL) to perform high precision measuring between satellites is a technology to implementing autonomous operation of navigation satellite constellation, and Dual-One-Way Ranging (DOWR) of Ka band is an effective way to carry out high precision measurement between satellites. Ka DOWR data of satellite-ground could be achieved by setting up the measuring link between orbiting satellite and pseudolite on the ground, analyzing precision it combined with precision analysis of troposphere and ionosphere correcting models, we can further infer the ranging precision of satellite–satellite. In order to evaluate the precision of satellite–ground Ka DOWR data, a method of using SLR data as exterior checking for comparison is proposed. The raw data of Ka and SLR contain environment effect, and their measuring time and spatial reference do not coincide. To achieve high precision evaluation of Ka DOWR data by SLR, it is needed to go through the environment error correction, time, and spatial reference formalization and some other steps. The errors in the steps will have impact on the final precision evaluation result. In order to verify the feasibility of this evaluation method, this paper starts from the principal of Ka DOWR and SLR, then analyzes the error sources that impact the evaluation result and expounds the principle and process of this evaluation method. By setting up the ground test simulation platform of ISL, the Ka satellite-ground DOWR and SLR data are obtained and analyzed. The simulation results show that the evaluation precision of this proposed method is in the magnitude of centimeters, which can provide reference for the analysis of the satellite–ground test data of ISL.