Patent ID: 7825855
Filing Date: 2010-11-02
Classification: G01S

Abstract:
1. A method for compiling assistance data for transmission to a mobile terminal of a wireless communications network, said terminal having an associated satellite positioning system receiver, said method including; determining which satellites of a satellite positioning system constellation are potentially visible to the mobile terminal; determining on the basis of at least one predetermined criterion the likelihood that each of the potentially visible satellites will actually be used by the mobile terminal when determining its position; selectin a plurality of satellites from the potentially visible satellites having the greatest likelihood that the mobile terminal will use that satellite when determining its position; and compiling assistance data to be transmitted to the mobile terminal for the selected satellites; wherein the likelihood that each of the potentially visible satellites will be used by the mobile terminal when determining its position is determined based, at least in part, on historical data relating to the probability of a mobile terminal achieving a successful location determination when in the geographical area of the mobile terminal.