A New Window-Based Program for Quality Control of GPS Sensing Data

The main purpose of this study is to develop a new Windows-based program that calculates a quality control parameter that shows the quality of Global Positioning System (GPS) observations using GPS data in a Receiver INdependent Exchange (RINEX) format. This new program, Global Positioning System Quality Control (GPSQC), allows general GPS users to easily and intuitively check the quality of GPS observations before post-processing, which will lead to the improvement of GPS positioning precision in diverse areas of GPS applications. The GPSQC is designed to control the multi-path, cycle slip, and ionospheric errors of L1 and L2 signals in GPS observations. The GPSQC was developed using C#.NET language for the Window series with Microsoft Graphical User Interfaces (MS GUIs). This program gives brief information for GPS observations, time series plots, graphs of quality control parameters, and a summary report in MS word, Excel and PDF formats. It can simply perform quality checking of GPS observations that is difficult for surveyors conducting field work. We expect that GPSQC can be used to improve the accuracy of positioning and to solve time-consuming problems due to data loss and large errors in GPS observations.