DSCS-2 (Defense Satellite Communications System 2) provides secure voice and data communications for the US military. The contract was managed by the DCA (Defense Communications Agency) for the USAF.
These satellites are the follow-on program to the first generation IDCSP (IDSCS, DSCS-1) satellites, but are operated from a real geostationary orbit.
The DSCS-2 spacecraft are spin stabilized with a despun antenna platform. Body mounted solar cells produced 535 watts. Three NiCd batteries provide 36 AHr total. Hydrazine propulsion system. The payload consisted of two 20 Watt X-Band transponders with 500 MHz bandwidths. Steerable narrow beam antennas and drive mechanism for communications privacy. Capacity is 1300 voice channels or 100 Mbps of data. Compatible with ground-portable units.
DSCS-2 satellites were injected directly into GEO by the Titan-3(23)C launch vehicle without the need to incorporate an apogee kick engine.
DSCS-2 4 remained in use as a test asset for more than 25 years. The last satellite, DSCS-2 15, was deactivated in 2008.