Advanced co-design of message structure and channel coding scheme to reduce the time to CED and to improve the resilience for a Galileo 2nd Generation new signal

Lorenzo Ortega Espluga (1) , Charly Poulliat (2, 3) , Marie-Laure Boucheret (2, 3) , Marion Aubault (4) , Hanaa Al Bitar-El Natour (5)

1 TéSA - Laboratoire des TéléCommunications Spatiales et Aéronautiques (Institut Mines-Télécom-Télécom Bretagne/site de Toulouse -UEB)
2 IRIT-SC - Signal et Communications
3 Toulouse INP - Institut National Polytechnique (Toulouse)
4 CNES - Centre National d'Études Spatiales [Toulouse]
5 TAS - Thales Alenia Space [Toulouse]

Reducing the Time To First Fix (TTFF) and improving the resilience of future Galileo signals are two important characteristics, especially when considering urban environments. To reach these goals, we studied two new advanced techniques based on the co-design of the message structure and the channel coding scheme. The first technique proposes a reduction of time needed to retrieve the data by reinforcing the parity check matrix structure constraints. The second technique provides an enhancement of the retrieved data error rate in parallel to a reduction of the time needed to retrieve the data thanks to a new co-design requirement based on a family of codes inspired from the rate-compatible root LDPC codes. The results obtained are promising, since the time to retrieve the data (and thus the TTFF) is significantly reduced, while keeping a good level of demodulation performance.

Mots clés: GPS navigation

Domaines: Systèmes embarqués

Lorenzo Ortega Espluga, Charly Poulliat, Marie-Laure Boucheret, Marion Aubault, Hanaa Al Bitar-El Natour. Advanced co-design of message structure and channel coding scheme to reduce the time to CED and to improve the resilience for a Galileo 2nd Generation new signal. ESA Workshop on Satellite Navigation Technologies and European Workshop on GNSS Signals and Signal Processing (NAVITEC 2018), Dec 2018, Noordwijk, Netherlands. pp.0. ⟨hal-02279418⟩