Indian Regional Navigational Satellite System 1D is the satellite in the IRNSS constellation. Constellation includes seven satellites and IRNSS 1D is the fourth. It was launched after IRNSS-1A, IRNSS-1B, IRNSS-1C. IRNSS-1D provides navigational services to the region and it is the only one from the group. Satellite was launched on 28 March 2015 onboard ISRO's PSLV-C27 (Satish Dhawan Space Center, Sriharikota).
IRNSS-1D has two payloads: CMDA ranging payload with laser retro-reflector and a navigation payload. It produces signals at L5 and S-band. Thanks to design this satellite is inter-operable and compatible with Galileo and GPS (Global Positioning System). The power of satellite is generate from two solar arrays (life-time ten years, power up to 1660 watts).
IRNSS-1D will be usefull in augmenting the satellite based navigation system of India. It will develop towards South Asia and provide mapping services, tracking and navigation.