Defense Industry Daily
DSP satellites use an infrared sensor to detect heat from missile and booster plumes against the earth’s background. The first DSP was launched in 1970, and the final DSP bird was orbited in 2007.
The spacecraft and sensor were upgraded several times throughout production to protect against evolving worldwide threats. In 1995, improvements were also made to ground processing systems, in order to improve detection of short-range missiles.
Today’s DSP-I (improved) weighs 5,200 pounds vs. just 2,000 pounds for the original versions, requires 1,275 watts of power vs. 400, uses 6,000 detectors vs. 2,000, and is approximately 33 feet long and 14 feet in diameter. Recent technological improvements in sensor design include above-the-horizon capability for full hemispheric coverage and improved resolution, as well as increased on-board signal-processing capability.
The DSP constellation is being replaced by the SIBRS-High program. Unfortunately, that program has been beset by massive cost overruns, technical challenges that continue to present problems, and uncertain performance. Despite its problems, the U.S. Air Force is proceeding with the program. Until SIBRS-High is ready, however, the DSP constellation will be the USA’s sentinel against ballistic missile launches.
http://www.defenseindustrydaily.com/dsp-satellites-supporting-americas-earlywarning-system-02650/
