Ballistic Missile Early Warning System
Quick Summary
The Ballistic Missile Early Warning System (BMEWS) utilizes large, ground-based radar technology to detect and track ballistic missiles. These systems are significantly larger than aircraft detection radars due to the longer ranges involved, requiring maximum detection ranges of 2,000 to 3,000 nautical miles. BMEWS radars operate at lower frequencies, typically in the UHF range (420–450 MHz), and use phased-array antennas. These antennas can steer the radar beam electronically without mechanical movement, allowing for rapid scanning and tracking of multiple targets.
The primary function of BMEWS is to provide warning of intercontinental ballistic missiles (ICBMs). The radar systems must not only detect potential threats but also distinguish actual warheads from confusion targets like decoys and debris. Advanced variants, such as those used in the BMEWS network, are capable of detecting satellites and other space objects in addition to ballistic missiles. Over-the-horizon radars and satellite-borne infrared detectors can provide earlier warning than ground-based systems, which are limited by the Earth's horizon.12
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