Raytheon Corporation has developed an anti-missile (of the portable, shoulder fired variety) system for civilian air airports. Called Vigilant Eagle, the system uses a network of heat sensitive missile detectors, mounted like cell phone antenna, all over the airport area. When at least two of these detect a missile launch, a beam of electromagnetic energy fries the anti-aircraft missiles electronics, causing it to miss the airliner (landing or taking off) it was aimed at. The High-power Amplifier-Transmitter (HAT), does the zapping. This is a large, billboard sized array of small electronic emitters, that can send a powerful bean of electronic in any direction. 

MANPADS (portable SAMs, or Surface to Air Missiles) are seen as a major terrorist threat against civilian aviation. The air transport industry is looking for a cost effective way to deal with this threat.  Vigilant Eagle will cost about $25 million per airport, which is a tenth of the cost for equipping individual aircraft with anti-missile systems. About 70 percent of air traffic in the United States goes in and out of just 30 airports. Vigilant Eagle has been tested successfully, but is relatively new technology. However, this directed energy type of weapon is showing up in many areas, and is not some off-the-wall idea. Directed energy devices have been in the works for decades, and are now finally entering service.