GAGAN is an Indian implementation of
Satellite Based Augmentation System (SBAS),
developed jointly by Airports Authority of India (AAI) and Indian Space
Research Organisation (ISRO). It is in final operational phase with all the
required ground and space segments ready. With the availability of GAGAN
signal-in-space (SIS), the improvement in position solution is investigated
using the two collocated dual frequency GPS receivers. One of the receivers was
configured as SBAS
receiver and the other was kept as GPS stand-alone receiver. It is found that accuracy in
position improved
significantly in SBAS receiver due
to GAGAN correction. The impact of scintillation on GNSS was also investigated in terms of position
degradation and loss of lock of the satellite signals. The manyfold effects of
scintillation on GPS and SBAS are discussed in detail. The results indicate
~15% reduction in number of measurements due to loss of lock during severe
scintillation.
References
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