Centimeter-Level, Real-Time Kinematic Positioning with GPS+GLONASS C/A Receivers

Abstract

This paper describes the main features of a new algorithm developed for a real-time kinematic (RTK) engine to process GPS+GLONASS C/A-code and carrier phase differential data. The goal of the development was to implement the algorithm in low-cost receivers that are capable of tracking the signals of both constellations. The test results, also presented, show that combined RTK processing ensures very fast (often instant) on-the-fly (OTF) ambiguity resolution (AR) and centimeter kinematic accuracy for short baselines under an open sky. Under a partly blocked sky or in a severe environment (urban areas, deep mines, under trees) where GPS-only RTK often is not able to work, GPS+GLONASS RTK still ensures reliable decimeter-and often centimeter-level real-time accuracy. The data was collected using Ashtech GG24 receivers with the RTK option installed.