For supporting a
satellite based positioning of a mobile arrangement (30,40) with assistance data, a communication network converts parameters of a dedicated
orbit model describing a movement of a
satellite (50,60), which dedicated
orbit model is defined for a particular
satellite based
positioning system, into parameters of a common
orbit model describing a movement of a satellite (50,60). Alternatively or in addition, the network replaces a reference value that is based on a satellite based
positioning system time in available parameters of an orbit model by a reference value that is based on a communication
system time. After the parameter conversion and / or the reference value replacement, the parameters are provided as a part of assistance data for the satellite based positioning. Alternatively or in addition, a set of data is transmitted in one direction between the mobile arrangement and the communication network, which is independent of the employed positioning mode.