Abstract: A receiver of a satellite positioning system, the receiver being capable of receiving signals from satellites, determining an estimated latitude and determining an estimated longitude. The receiver being responsive to the estimated latitude, estimated longitude and information indicating orbits of the satellites for identifying a group of available satellites, for performing a search for signals transmitted by satellites which belong to the group of satellites, and for calculating the positional coordinates of the receiver based on signals received from satellites which belong to the group of satellites.

Abstract: The invention relates to a receiver of a satellite positioning system comprising: reception means for receiving signals transmitted by satellites, means for measuring the magnetic field of the earth at the location of said receiver in order to obtain a measurement result describing properties of said magnetic field and for obtaining an estimated latitude based on the measurement result, a clock for keeping track of the local time at the location of the receiver, and means for comparing the local time indicated by said clock and the satellite time in order to identify a time zone where said receiver is located and for obtaining an estimated longitude based on said identified time zone, said receiver being responsive to said estimated latitude, estimated longitude and information indicating orbits of the satellites for identifying a group of available satellites, for performing a search for signals transmitted by satellites which belong to said group of satellites, and for calculating the positional coordinates

Abstract: The invention relates to a method and an apparatus for codeless GPS positioning. According to the method, the unit (2) to be positioned receives GPS signals from several satellites (4), the codes of the GPS signals are removed, and the extracted carrier signals are transmitted out from the unit (2) to be positioned for the purpose of determining the position and/or velocity of said unit (2) to be positioned. According to the invention, the carrier signal frequencies are detected by means of a phase-locked loop and the thus detected signals are transmitted in digital format out from the unit (2) to be positioned for the purpose of further processing.