Veripos HF Stations

Each VeriposHF reference station consists of a Sercel (now Thales Navigation) NDS system which operates independently from any other infrastructure such as a Network Control Centre (NCC) or communications network.

The Sercel NDS system consists of a single frequency GPS receiver which computes a pseudorange correction for each satellite in view.  All corrections are then formatted into the proprietary format for broadcast to the user via the HF radio link.  Two transmission frequencies (nominally 1.6MHz and 3.5MHz) are used simultaneously to broadcast the differential corrections to the user.  This dual frequency transmission scheme enables the Veripos Standard HF service to operate at ranges up to 700km from each reference station.