GPS RTK Positioning Using a Regional Reference Network: Theory and Results

Abstract

This paper describes the design, operation and testing of a RTK GPS system based on the use of a multi-reference station approach. The use of a multi-reference station network, as opposed to a single reference station, results in a larger service area coverage, a lower number of reference stations, increased robustness, and a higher positioning accuracy. The effective distance to the nearest reference station required to resolve the carrier phase integer ambiguities increases by a factor of 1.5 to 3. An overview of the approach is given which is sub-divided into two steps, namely error modeling and correction generation. A series of real-time tests conducted using a regional reference network in Brazil and a local reference network in Calgary, demonstrate the effectiveness of the approach to reduce the time to integer ambiguity resolution, and to increase the distance over which centimeter level accuracies can be achieved.