Space Applications Centre at Ahmedabad and the transponders it builds for INSAT and GSAT
Background
Space Applications Centre, or SAC, is at Jodhpur Tekra in Ahmedabad and is spread over two campuses. Its core strength is building space borne and air borne instruments and payloads, and putting them to use for the country's communication, navigation and remote sensing needs. The centre also worked on ISRO's scientific and planetary missions, Chandrayaan-1 among them. Communication transponders made here for the INSAT and GSAT satellite series are used for VSAT, DTH, internet, broadcasting and telephones. SAC designs optical and microwave sensors for satellites, and writes the signal and image processing software and the geographic information software that go with them. Its facilities include payload integration laboratories, electronic and mechanical fabrication shops, environmental test facilities and image processing and analysis setups. The centre runs a nine-month post graduate diploma for students from the Asia Pacific region under CSSTE-AP, in satellite meteorology and in communication.
In plain words
SAC Space Applications Centre — The ISRO centre at Ahmedabad that builds payloads and satellite instruments.
Transponder Transponder — The device on a satellite that receives a signal from the ground and sends it back.
CSSTE-AP Centre for Space Science and Technology Education in Asia and the Pacific — The programme under which SAC teaches post graduate diploma students from the region.