Internally mounted electronic warfare system that detects and interprets radar signals and automatically selects the proper countermeasure to jam or deceive them. The AN/ALQ-165 ASPJ was a joint U.S. Navy/Air Force program to provide a Defensive Electronic Countermeasure (DECM) system for fighter aircraft. The receiver was designed to operate in a very dense signal environment projected to the year 2010. The Air Force droppe d out of the program in January of 1990. The ASPJ was to have been installed in most first-line Navy and Air Force tactical aircraft. The U.S. Navy continued ASPJ development.