Software Tool for Differential GPS Correction GTDIFCOR
Purpose
GTDIFCOR is new software designed for high-precision navigation solutions, built using both least squares method and smoothing Kalman filtration. GTDIFCOR is capable of providing solution as accurate as 1cm and works both with airborne receivers and with geodesic "stop-and-go" tasks.
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| Fig. 1. GTDIFCOR's solution (red) versus another differential correction software's solution (green). Altitude shown in meters. GTDIFCOR's solution noise level on this standing occupation is less then 2cm. |
Features
Comparing to other differential correction software, GTDIFCOR works faster and has less slips and gaps in the solution. This is especially true for large data files, where Kalman filtration takes advantage over traditional least squares method.
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| Fig. 2. GTDIFCOR's solution (red) versus another differential correction software's solution (green). Altitude shown in meters. |
By default GTDIFCOR outputs receiver's position and velocity to a Geosoft XYZ file. But you can opt to add acceleration solution block to the main program and thus get complete picture of receiver's motion. GTDIFCOR can also be easily upgraded with some useful features, such as L2 processing, GLONASS support and relative positioning mode for roaming base occupations.
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| Fig. 3. GTDIFCOR's altitude (red) and vertical velocity (green) solution on a standing occupation. |
On the Fig.3 standard deviations of this solution are 1cm, 1*10-3 m/sec, 1*10-3 m/sec and 1.5*10-3 m/sec for position, V_EAST, V_NORTH and V_UP respectively.
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| Fig. 4. Vertical acceleration (blue) and its low-frequency (60-seconds mean) component (red). |
On the Fig.4 standard deviation of low-frequency component is 0.5 mGal.
Built with simplicity in mind, GTDIFCOR is both powerful and easy-to-use tool. It can be run from command line (ensuring you can write and execute batch files to process large arrays of data) or it can be called from an external front-end program. All necessary parameters (such as mask for satellites elevation, satellite processing controls, etc.) are available in a special configuration file.
