Conversion methods geocentric (x, y, z) and geodetic (B, L, h) coordinates

Today, GPS measurements are used densely in engineering surveys which require high accuracy and in construction of WGS84, ITRS and ETRS coordinate systems which are bases of ground geodetic reference networks. Calculation of ellipsoid geographic coordinates (B, L, h) from geocentric cartesian coordinates (x, y, z) or vice versa is one of the frequently used geodetic calculations. Because Turkey is in seismic belts, geodetic reference points should be determined accurately. Also, operation speed of conversion algorithm is a preference reason in the projects having lots of points. For these reasons, many methods have been developed. While calculation of (x, y, z) from (B, L, h) is common, there are different methods for inverse conversion. In this paper, the solution algorithms of twenty seven different methods were developed for calculation of (B, L, h). When the case that latitude is between , elipsoidal elevation is between and the other components are fixed, accuracies of the methods were examined with respect to variations of latitudes and elevations. Besides, some researches were realized for determining of operation time of the methods. At the end of the application, the method appropriate for these comparison criteria has been proposed.