(U) DSCS II satellites represented an upgrade of the capabilities of the early DSCS satellites which were the Phase I space segment of DSCS. The DSCS II systems emphasized hardening, anti-jamming protection, and an increase in channel capability over the original DSCS satellites. A full compliment of four DSCS II satellites was achieved on 14 December 1978. The final DSCS II satellite is muted and is being maintained as an inactive spare.
(U) The first DSCS II satellite was launched in Nov 1971. The DSCS II satellites were launched in pairs. Each DSCS II satellite has four antennas. Two 18-degree earth coverage horns and two steerable dish antennas. They are all mounted on the inner shell of the satellite platform which is despun to ensure the antennas always point towards the Earth. The outer shell is spun to provide stability. The two steerable dish antennas provide spot beam coverage and both can receive and transmit simultaneously. One dish antenna provides area spot beam coverage using a 6-degree beamwidth. The other antenna provides narrower spot beam coverage with a 3-degree beamwidth. The four channels provide the flexibility to handle a wide variety of links and to interface with many different sizes of terminals. All the communication subsystem assemblies are redundant.
(U) The last DSCS II satellite was launched in 1989 onboard a Titan 34D with the DSCS III satellite F4. DSCS II satellite have been replaced by nine DSCS III satellites in orbit including five primary and four reserve satellites. The final DSCS II satellite is muted and is being maintained as an inactive space. The DSCS Service Life Enhancement Program (DSCS SLEP) provides performance enhancements for the last four DSCS III satellites. These enhancements are designed to increase the DSCS tactical system capacity by over 200 percent.
(U) To be supplied.
|DSCS II||DSCS II|
|Adv Wideband Satellite (AWS)||Advanced Wideband Satellite (AWS)|
|DISA STEP||Defense Information Systems Agency (DISA) Standard Tactical Entry Point (STEP)|
|DSCS III||Defense Satellite Communications System (DSCS) III|
|Eastern Range||Eastern Range|
|Lightwt Multi-band Sat Terminal||Lightweight Multi-band Satellite Terminal (LMST)|
|MIDAS||Multiplexer Integration and DCSS (Digital Communications Satellite Subsystem) Automation System (MIDAS)|
|STAR-T||SHF Tri-Band Advanced Range-Extension Terminal (STAR-T)|
|Satellite Operations||Satellite Operations|
|SHF Satellite Systems||Super High Frequency (SHF) Satellite Systems|
|MILSATCOM||SPACE FORCE ENHANCEMENT: MILSATCOM|
|National Security Space Road Map||Integrated System Road Map|
|Navy EHF SATCOM Program (NESP)|
(U) Maj Steven Cliatt, SMC, Open Phone: (310) 336-4475.
(U) 01 February 1997
(U) Road Map Production Date: 23 June 2001