Sbirs Hotel Reservations in
Spa 		Website Links For
Infrared 		 

Information About

Sbirs
  CATEGORIES ABOUT SPACE-BASED INFRARED SYSTEM
   
reconnaissance satellites of the united states
   
missile defence
   
SHOPPER'S DELIGHT
 
Shop For:  
Department
Price Minimum:
Price Maximum:
      




BACKGROUND

Based on its experiences with the launching of short-range theater missiles by Iraq during the 1991 Persian Gulf War , the U.S. Department of Defense ( DOD ) concluded that expanded theater missile warning capabilities were needed and it began planning for an improved infrared satellite sensor capability that would support both long-range strategic and short-range theater ballistic missile warning and defense operations. In 1994 , DOD studied consolidating various infrared
space requirements, such as for ballistic missile warning and defense, technical intelligence, and battlespace characterization, and it selected SBIRS to replace and enhance the capabilities provided by the Defense Support Program . The Defense Support Program is a strategic surveillance and early warning satellite system with an infrared capability to detect long-range ballistic missile launches that has been operational for about 30 years. DOD has previously attempted to replace the Defense Support Program with:
  • the Advanced Warning System in the early 1980s

  • the Boost Surveillance and Tracking System in the late 1980s

  • the Follow-on Early Warning System in the early 1990s

  • the Attack and Launch Early Reporting to Theater (ALERT) System in the mid-1990s.


According to the GAO , these attempts failed due to immature technology, high cost, and affordability issues. SBIRS is to use more sophisticated infrared technologies than the Defense Support Program to enhance the detection of strategic and theater ballistic missile launches and the performance of the missile-tracking function.


SBIRS HIGH

SBIRS High is to consist of four satellites operating in geosynchronous earth orbit and sensors on two host satellites operating in a highly elliptical orbit. SBIRS High will replace Defense Support Program satellites and is primarily to provide enhanced strategic and theater ballistic missile warning capabilities. The SBIRS High program includes the consolidation of the three existing DSP ground facilities (two overseas and one in the US) at a single U.S. ground station to reduce costs. SBIRS High is in the engineering and manufacturing development phase, with a scheduled first launch in 2005 .


SBIRS LOW

The SBIRS Low program is expected to consist of about 24 satellites in low earth orbit. The primary purpose of SBIRS-low is tracking ballistic missiles and discriminating between the warheads and other objects, such as decoys, that separate from the missile bodies throughout the middle portion of their flights. It has two major sensors which it must coordinate with an on-board computer:

  • a scanning infrared sensor, which is to acquire ballistic missiles in the early stages of flight.

  • a tracking infrared sensor, which is to follow missiles, warheads, and other objects such as debris and decoys during the middle and later stages of flight. The tracking sensor will be cooled to very low temperatures.


SBIRS Low's original deployment schedule was 2010 , the date when its capabilities are needed by the National Missile Defense System. The first SBIRS Low satellites need to be launched in 2006 if full deployment is to be accomplished by 2010 .

Space Tracking and Surveillance System

In 2001, the Missile Defense Agency assessed the programs needed for a national ballistic missile defense system (BMDS) and found that they were lacking in the relatively new arena of space. The MDA decided to absorb the SBIRS Low constellation in its very early stages of development and renamed the program the Space Tracking and Surveillance System (STSS). This transition changed the direction of the program somewhat, but the overall mission remained the same--detection and tracking of ballistic missiles through all of its phases of flight.

STSS uses an acquisition IR sensor to detect the launch of a ballistic missile and a tracking sensor with a "soda-straw" field of view (FOV). Once the boost phase is complete, the ballistic missile becomes exactly that--ballistic. This means that gravity is the only force acting on the ICBM and without the firing engines, the object becomes very dim in what is called the missile's "midcourse" phase. Because of its low earth orbit, the tracking sensors can track the midcourse objects much earlier than it could in a higher orbit. This is because the midcourse object is against the cold background of space and the temperature difference is much more pronounced, enabling easier and more complete tracking.

STSS remains roughly on the same developmental timeline as that of SBIRS Low. Two flight demonstration satellites will be launched in 2007. As opposed to its sister program SBIRS, STSS remains on schedule and within costs.

Retrieved from "http://en.wikipedia.org/wiki/Space-Based_Infrared_System"


SOURCE

Space-Based Infrared System Low at Risk of Missing Initial Deployment Date, U.S. General Accounting Office, Feb. 2001.