Abstract: A method for providing a differential code bias, in particular a primary differential code bias and a secondary differential code bias, in a global navigation satellite system using satellites communicating by using at least a first signal and an additional first signal both having a first carrier frequency and a second signal and an additional second signal both having a second carrier frequency, where a primary differential code bias for the first signal and the second signal is determined and wherein the primary differential code bias is used for determining, and in particular providing, a secondary differential code bias for the additional first signal and the additional second signal.

Abstract: A method for determining a state parameter of a global navigation satellite system receiver and an apparatus, in particular its absolute position, determining being based on—a measured information including a pseudorange, a carrier phase and/or a Doppler frequency measurement, —broadcast information on the satellite orbits and clock offsets, and—high accuracy correction information of a satellite positions, clock offsets, code and/or phase biases, the method comprising: —determining a satellite position estimate and a clock offset estimate based on the broadcast information, —determining a corrected satellite position and a corrected clock offset based on the satellite position estimate and the clock offset estimate by using the high accuracy information, in particular the high accuracy correction information of the satellite position and the clock offset.

Abstract: A method for providing authenticated correction information, in particular orbit, clock and bias/offset correction information, to a mobile receiver in a GNS system, including: receiving raw data from satellites at a plurality of reference stations; forwarding the raw data received at the reference stations to a central computation unit, in particular to a single central computation unit, using a data stream, in particular a common data stream; determining the correction information at the computation unit based on the raw data received from the different reference stations and transmitting the correction information via at least one satellite to the receiver for reliably determining a position of the mobile receiver.