GSAT-15 is an ISRO communication satellite with 24 Ku-band transponders and a GAGAN navigation payload. An Ariane 5 launched it from Kourou in November 2015.
GSAT-15 carries 24 Ku-band transponders that replace the Ku-band capacity of INSAT-3A and INSAT-4B. They support direct-to-home TV and VSAT networks in India. A Ku-band beacon helps ground antennas point at it.
It also carries a GAGAN payload in the L1 and L5 bands, which corrects GPS positions for aircraft. GSAT-15 was the third satellite with GAGAN, after GSAT-8 and GSAT-10, giving the service a spare in orbit.
It weighed 3,164 kg at lift-off and 1,440 kg dry. Solar arrays give 6,200 W, and three 100 ampere-hour lithium-ion batteries store power. It was designed for a 12-year life.
An Ariane 5 ECA rocket (flight VA-227) launched it from Kourou, French Guiana, in November 2015. GSAT-15 sits in geostationary-orbit at 93.5° East, sharing the slot with INSAT-3A and INSAT-4B.
The public satellite catalogue carries GSAT-15 with an operational flag.