A GAGAN (GPS Aided Geo Augmented Navigation) is an Indian SBAS (Satellite Based Augmentation System) intended to provide accurate and reliable navigation information for all phases of flight over the Indian FIR (Flight Information Region) and in the adjoining areas applicable for safety-of-life operations meeting the performance requirements of ICAO. The implementation of the GAGAN program is being realized through the following two phases…

CURRENTLY the trend is that more and more project authorities are mandating use of GPS for control work and private surveyors have to comply with this requirement. Dual frequency DGPS have been beyond the financial reach of these surveyors as such most prefer to invest in single frequency DGPS, which cost almost one third the cost of dual frequency DGPS.