A Dual Frequency GPS Receiver (L1/L2c or L1/Lp) for Space Applications in LEO and GEO Orbit

This paper presents the functional and physical characteristics, as well as laboratory performance test results, of a new GPS space receiver, able to process the new L2CS signal. Real-time spacecraft navigation based on spaceborne GPS receiver is nowadays a common technique for Low-Earth Orbits (LEO). A first generation of a spaceborne GPS receiver was developed and designed by ALCATEL ALENIA SPACE in 1999 to fulfil a wide set of missions, including high-altitude orbits, under ESA and CNES contracts, the European and French space agencies. This receiver is called the TOPSTAR 3000 (T3000). Today, a more compact GPS receiver family (dual or single frequency) has been developed with a funding partnership of the European Space Agency (ESA) and French Space Agency (CNES). This new receiver generation is called the T3000 G2, capable of processing the new GPS (L2CS) and pseudolite signals (Lp). The first space flight is expected for mid 2007 for an in orbit technology demonstration mission of ESA, called PROBA-2.