Análise da acurácia de receptor GNSS de baixo custo em posicionamento estático e cinemático

Abstract

This study evaluates the positional accuracy of a low-cost GNSS receiver (U-blox F9P) in comparison to a geodetic-grade reference receiver (Emlid RS2), investigating its viability for applications in hydrography. The methodology consisted of static and kinematic surveys in Post Processed Kinematic (PPK) and Post-Processed Static (PPS) modes, using the RTKLib software and data from stations of the IBGE's Brazilian Network for Continuous GNSS Monitoring (RBMC). For the quantitative analysis, a Python script was developed to perform coordinate transformation from the geodetic system to Universal Transverse Mercator (UTM), calculate the differences, and compute error metrics, especially the Root Mean Square Error (RMSE). The results from the static survey demonstrated centimetric accuracy and, considering a 95% confidence level, the horizontal and vertical uncertainties met the criteria of the International Hydrographic Organization (IHO) S-44 "Exclusive Order" standard regarding fixed objects, aids to navigation, and significant features for navigation above the Vertical Datum. The analysis of the kinematic survey corroborated the previous result, with high agreement between the trajectories surveyed with the low-cost receiver and the reference receiver. It is concluded that the low-cost receiver constitutes an alternative to meet the geodetic demands of hydrography in applications where post-processing is a suitable technique.