Reference systems

Abstract

The basic equation which relates the range ϱ with the instantaneous position vector ϱs of a satellite and the position vector ϱr of the observing site reads 2.1{\$}{\$}{\backslash}varrho = {\backslash}left{\backslash}| {\{}{\backslash}rho ^s - {\backslash}rho {\_}r {\}} {\backslash}right{\backslash}|.{\$}{\$}In Eq. (2.1), both vectors must be expressed in a uniform coordinate system. The definition of a three-dimensional Cartesian system requires a convention for the orientation of the axes and for the location of the origin.