Dual-Frequency GPS Precise Point Positioning with WADGPS Corrections

Abstract

The goal of the research described in this paper is the design of a GPS dual‐frequency data processing technique capable of producing high‐accuracy positioning results with wide area differential GPS (WADGPS) corrections. The main issues in using WADGPS corrections for dual‐frequency GPS point positioning are the satellite clock referencing issue and how to handle the increased noise level by use of the ionosphere‐free dual‐frequency combination. To address these concerns, a sequential forward carrier‐phase smoothing technique which utilizes the fully combined uncertainty for both systematic and random errors in the smoothing process has been designed. To account for the satellite clock referencing issue, the effects of the satellite instrumental biases have been precisely investigated and the observation equations for the different observables assuming the source of corrections is WADGPS have been developed. Results determined via developed software indicate that positioning accuracy at the few decimeter‐level is attainable at a 95% confidence level.

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