Space Based Infrared System
Published August 19, 2015
The SBIRS program is the follow-on capability to the highly successful Defense Support Program (DSP). The SBIRS program was designed to provide a seamless operational transition from DSP to the Nation's next-generation Overhead Persistent Infrared sensors to meet jointly defined requirements of the defense and intelligence communities in support of the missile early warning, missile defense, battlespace awareness, and technical intelligence mission areas.
The SBIRS architecture includes a resilient mix of satellites in geosynchronous earth orbit (GEO), payloads in highly elliptical orbit (HEO), as well as ground-based hardware and software. The integrated system supports multiple missions simultaneously, while providing robust performance with global, persistent coverage. Air Force Space Command's 460th Operations Group is responsible for conducting HEO, GEO, and DSP operations at all fixed ground sites while the Air National Guard Unit, 233d Space Group, operates the Mobile Ground System (MGS) to provide survivable and endurable mission support for the DSP constellation. The SBIRS program is managed by the Remote Sensing Systems Directorate (RS) at the U.S. Air Force Space and Missile Systems Center. Lockheed Martin (LM) Space Systems Company is the prime contractor responsible for program management, systems engineering, and spacecraft development, while LM Information Systems and Global Solutions is the ground systems developer. Northrop Grumman Electronic Systems is the payload subcontractor for the infrared sensors.
Two HEO sensors and two GEO satellites are certified for mission operations. The first and second GEO satellites were launched on United Launch Alliance's (ULA) Atlas V rocket from Space Launch Complex (SLC) 41 at Cape Canaveral Air Force Station. With updates to the Increment 1 ground system (declared operational with the DSP satellite system in December 2001), the SBIRS Mission Control Station (MCS) is United States Strategic Command's focal point for Overhead Persistent Infrared (OPIR) operations, consisting of the constellation of GEO satellites, HEO sensors, and the legacy DSP satellites. Increment 2, the next major SBIRS ground update, was divided into two software releases; Block 10.3 and Block 20. Block 10.3 is on track for transitioning to operations in mid- 2016, replacing all the Increment 1 software and improving infrared event detection. The SBIRS Survivable/Endurable Evolution (S2E2) program will replace the aging MGS, initially designed for support of DSP operations in the 1960s.
The SBIRS sensors are designed to provide greater flexibility and sensitivity than the DSP infrared sensor and detect short-wave and mid-wave infrared signals, allowing SBIRS to perform a broader set of missions. These enhanced capabilities result in improved prediction accuracy for global strategic and tactical warfighters. The on-going evolution of the ground system has also resulted in improved mission processing software, resulting in increased event message accuracy, and reduced manpower for support and operations of the DSP and SBIRS portfolio.
The GEO spacecraft bus consists of a militarized, radiation-hardened version of the Lockheed Martin A2100 spacecraft, providing power, attitude control, command and control, and a communications subsystem with five separate mission data downlinks to meet mission requirements, including system survivability and endurability requirements. The GEO infrared payload consists of two sensors; a scanner and a step-starer. The scanning sensor continuously scans the earth to provide 24/7 global strategic missile warning capability. Data from the scanner also contributes to theater and intelligence missions. The step-staring sensor, with its highly-agile and highly-accurate pointing and control system, provides coverage for theater missions and intelligence areas of interest with its fast revisit rates and high sensitivity. The HEO sensor is a scanning sensor, with sensor pointing performed by slewing the full telescope on a gimbal. Both the GEO and HEO infrared sensors gather raw, unprocessed data that are down-linked to the ground for mission processing. The GEO sensors perform on-board signal processing and transmit detected events to the ground, in addition to the unprocessed raw data.
o HEO sensor: approximately 7 ft x 4 ft x 3 ft
o GEO satellite: approximately 49 ft x 22 ft x 20 ft with all appendages deployed on-orbit
- Weight (all weights approximate)
o HEO sensor: 536 lbs
o GEO satellite: on-orbit, 5603 lbs, including a 1,100 lbs two-sensor payload and 430 lbs of fuel
- GEO power source: 2 deployable, sun-tracking solar arrays
- The first and second HEO payloads were announced on-orbit (with mission performance surpassing specifications) by the Air Force in November 2006 and June 2008, respectively.
- The first and second GEO satellites were launched on 7 May 2011 and 19 Mar 2013 respectively.