(U) Space-Based Infrared System - Low Earth Orbit (SBIRS-Low)

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)

Overview: (U)
(U)  The Space Base Infrared System (SBIRS) program is a global satellite system designed to meet the United States' infrared space surveillance requirements over the next 20 to 30 years.  It provides an improved capability over the existing Defense Space Program (DSP).  Like DSP, the system addresses critical warfighter requirements in the areas of missile warning, missile defense, technical intelligence, and battlespace characterization.  SBIRS is a program designed to satisfy user requirements on a cost effective basis by using existing technologies and methods. 

(U)  The SBIRS program consists of high altitude (SBIRS High)  and  low altitude (SBIRS Low) components.  SBIR High includes satellites in Geosynchronous Earth Orbits (GEO) and Infrared (IR) sensors on satellites in Highly Elliptical Earth Orbits (HEO).  SBIRS Low includes sensors on satellites in Low Earth Orbits (LEO).  SBIRS will be controlled from the ground through a number of ground assets.  Its ground assets include:  a CONUS-based Mission Control Station (MCS); a backup MCS; a survivable MCS possibly located with the Mobile Consolidated Command Center (MCCC); overseas Relay Ground Stations; Relocatable Terminals; and other associated communications links.  

(U) An objective of the SBIRS program is to expand its IR sensor capability to include the ability to collect other threats capitalizing upon their unique signatures. 

(U) SBIRS Low could augment the space surveillance mission area by using its sensors for detecting and tracking space objects above the horizon.  The number of sensors in the constellation would permit routine stereoscopic viewing and offer almost comprehensive instantaneous field of regard, 24 hours a day.  

Description: (U)
(U)  The SBIRS Low program consists of a to-be-determined (TBD) number of  satellites in Low Earth Orbits (LEO).  The LEO satellites compliment the SBIR High element by providing a unique precision mid-course tracking and discrimination capability critical for effective ballistic missile defense.  In addition, the LEO element provides an enhanced capability for missile warning, technical intelligence, and battlespace characterization.  

(U)  The source selection process to select two contractor teams for the Program Definition (PD)  portion of the SBIRS Low Component Program is currently in progress, with contract awards anticipated 1QFY99. The Low PD effort will result in an initial system design which will be used to develop, manufacture, deliver, operate and sustain the Low Earth Orbit (LEO) portion of the SBIRS System-of-Systems (SoS) architecture. The SBIRS Low system design includes a space segment and associated ground elements. This design must satisfy, as a minimum, the SBIRS Operational Requirements Document (ORD)requirements as allocated to the Low Component in the SBIRS Requirements Allocation Document(RAD). The design must also reflect PD cost/military utility trade study recommendations (i.e., Cost as an Independent Variable (CAIV) trades). Successful accomplishment of the SBIRS Low PD objectives will support a Milestone II decision to enter Engineering and Manufacturing Development (EMD) and downselect to a single EMD contractor team.

(U)  The SBIRS Low Program Definition and Risk Reduction (PDRR) phase, currently in progress,   will demonstrate program capabilities through an on-orbit, operational test of two demonstration systems   using known, representative threat targets.  The first of these systems, the Flight Demonstration System (FDS) is being developed by TRW/Raytheon.  The second, the Low Altitude Demonstration System (LADS) is being developed by Boeing North American and  will use the commercially based LM700 satellite bus.   The flight demonstration systems' objectives are: acquire, track, discriminate and report ballistic missiles from lift-off through midcourse; demonstrate acquisition and track handover between satellites;  downlink mission health and status data directly and via crosslink;  and demonstrate capability to perform missile warning.  The first planned launch date for the two FDS spacecraft is 4QFY00.  The satellites will be launched into a common orbit using a Delta II.  

(U)  Each SBIRS Low satellite consists of two sensors, one acquisition and one tracking sensor. The sensors operate in a variety of wavebands including short-wave infrared, medium-wave infrared, long-wave infrared, and visible. These wavebands allow the sensors to acquire and track targets of different temperatures.

(U) The acquisition sensor constantly scans from horizon to horizon using a large field of view, small aperture, and fast scan mode.  When a potential target is detected, the acquisition sensor begins a two dimensional (2D) track and passes the detection to the tracking sensor, which verifies the target and continues the track.  The tracking sensor uses a narrow field of view, large aperture, and staring mode to maintain the track through midcourse and re-entry.   

(U)  The current program will be followed by a deployment decision for the SBIR Low program in FY2001.  A decision to deploy the system will result in a projected SBIRS Low delivery date by 2006. SBIRS Low satellites will be launched 3 at a time using the Delta II launch vehicle.

User Impact: (U)
(U) SBIRS will incorporate new technologies that would enhance detection; improve reporting of ICBM, SLBM and tactical ballistic missiles; and provide critical midcourse tracking and discrimination data for national and theater missile defense.

Programmatics: (U)
(U) Programmed.
	(U) ATP: 09/2002 (4QFY2002).
	(U) IOC: 09/2006 (4QFY2006).

(U) Organizations and Funding:
	(U) AFSPC: Funding Source.
	(U) SAF/AQ: Funding Source.

Related Initiatives: (U)
(U) AEOS, COBRA BRASS, Delta II, DSP, Mid-Course Space Experiment, SBIRS High, SCIS, Space Sensors, Target Background Dissemination, THAAD

Related Requirements: (U)
(U) None.

Related Categories: (U)
(U) Contibuting Sensors, Satellite Operations, Space-Based Warning, Surveillance

Road Map Placements: (U)
(U) Major DoD Space Programs, National Security Space Road Map, SPACE CONTROL: NMD/ COUNTERSPACE, SPACE CONTROL: S.S. NETWORK, SURVEILLANCE AND WARNING.

Lead Office: (U)
(U) SMC.

Date of Information: (U)
29 April 1999

(The effects of any budget/program decisions made since the information was collected during 1997-98 are NOT reflected in the National Security Space Road Map (NSSRM).)