GSAT-15 set to replace dying INSAT-3A and 4B

GSAT-15 will replace two older spacecraft-INSAT 3A and 4B- that will likely to expire in few  months.It will provide replacement for the Ku-band capacity of INSAT-3A and INSAT-4B satellites to augment and support the existing DTH and VSAT services in the country. 
About GSAT 15:
1. weighing 3,164 kg, will be launched in on November 11 from Kourou in French Guiana (in South America) on the European Arianespace’s Ariane-5 launcher. 
2. It is an Indian geostationary Ku-band communications satellite.
3. The satellite built on the I-3K bus carries 24 Ku-band transponders and a GAGAN (GPS Aided Geo Augmented Navigation) payload.
4. The GAGAN payload of GSAT-15 will meet the in-orbit redundancy requirement for Safety of Life (SOL) operations benefiting the civil aviation services in the country.
INSAT 3A and 4B: INSAT-3A, launched in April 2003, has completed its 12-year life. INSAT-4B, flown in March 2007, got reduced to half its functions in 2010 after one of its two power-generating solar panels developed a snag.