ADE Gagan UAV
The name Gagan meaning is sky, heaven and the lucky number associated with is 3. It is a traditional name in the Sikh religion. Yhe name "Gagan" is clearly associated with a satellite based guidance system. It may also be used to designate a completely unrelated drone program, although this UAV is very poorly attested.
Indian developers have been working with Israel Aerospace Industries to develop three UAVs, the Rustom MALE and the short-range Pawan and Gagan. In March 2016 Indian defense forces finalized a blueprint to procure more than 5,000 UAVs over the next 10 years for about US $3 billion, and tenders will be restricted to domestic companies that can tie up with foreign firms. The Aeronautical Development Establishment (ADE) of DRDO is developing a variety of UAVs for the services, including, Navy projects such as Gagan tactical UAVs at a cost of $55 million with help from Israel.
India’s GAGAN system – short for “GPS And Geo-Augmented Navigation” – uses ISRO satellites to augment the GPS commercial signal, enhancing accuracy to close to military grade. The sensors Group has provided state of the art inertial and Global Navigation Satellite System sensors for the UAV flight control and guidance. The novel ATOL scheme, DGPS based on GAGAN (Indian SBAS) augmented with Radio altimeter has been evaluated on manned aircraft and RUSTOM II is the first to adapt this Scheme in India and it has been used successfully. This scheme will be used for all future project of ADE for ATOL.
The GPS aided geo augmented navigation or GPS and geo-augmented navigation system (GAGAN) is a planned implementation of a regional satellite-based augmentation system (SBAS) by the Indian government. It is a system to improve the accuracy of a GNSS receiver by providing reference signals.
The project is being implemented in three phases through 2008 by the Airport Authority of India with the help of the Indian Space Research Organization’s (ISRO) technology and space support. The goal is to provide navigation system for all phases of flight over the Indian airspace and in the adjoining area. It is applicable to safety-to-life operations, and meets the performance requirements of international civil aviation regulatory bodies.
To begin implementing an SBAS over the Indian airspace, Wide Area Augmentation System (WAAS) codes for L1 frequency and L5 frequency were obtained from the United States Air Force and U.SDepartment of Defense on November 2001 and March 2005. The system will use eight reference stations located in Delhi, Guwahati, Kolkata, Ahmedabad, Thiruvananthapuram, Bangalore, Jammuand Port Blair, and a master control center at Bangalore.