TABLE OF CONTENTS 
In this chapter, we will be introduced to the six basic types of countermeasures chaff, noise jamming, false targets, gate stealers, angle deception, and decoys. We will see how each is used, and learn how it is implemented and what its limitations are.
The simplest of all countermeasures, and historically the earliest to be used, is chaff. Originally strips of metal foil, chaff today consists of metal-coated dielectric fibers, billions of which can be stored in a small space (Fig. 1). Injected into the air stream, they hang in the air for long periods. When dispensed in large numbers, they can produce strong radar echoes.
Upon being dispensed, the chaff rapidly decelerates and, except for turbulence, soon has little motion. Consequently, its echoes are rejected by radars employing moving target indication (MTI), just as weather clutter is. Against radars without MTI, however, chaff can be highly effective. Dispensed by a few escorting aircraft, chaff can screen an entire raid. If fired forward, it may screen the dispensing aircraft, as well.
Even against radars with MTI, chaff has important uses. It may screen surface targets, which have little or no motion. Against an approaching radar guided missile, chaff at the very least introduces tracking noise in the missile's seeker. If...
