Radio Frequency Weapons and the Next Phase of TerrorismAbstract: This paper reviews several types of radio frequency ("RF") weapons currently in development. It discusses the different types of weapons that currently exist, explains why they would be useful to terrorists, and explores different ways to defend against them. Recent media articles have put forward the idea of ​​the “RF weapon,” something that has been described as if it were a magic gun capable of bringing the United States to its knees. While these weapons exist, the threat they pose is far less widespread and dangerous than articles like "Are RF Weapons Attacking Our Freedom?" propose. That said, however, the threat is real and steps must be taken to defend against RF weapons. One of the first distinctions to make in this discussion is between RF weapons and EMP weapons. An EMP (electromagnetic pulse) is usually used to detonate thermonuclear devices at high altitudes (500 miles or more) above the Earth. The resulting electromagnetic pulse paralyzes any electronic equipment in its path. Therefore, a nuclear device can be used to cripple the modern infrastructure of an entire nation [1]. An RF device is effective over a much smaller range, but can cause just as much damage [2]. According to David Shriner, a former military engineer and RF technology expert, there are several types of RF weapons, which are also called high-power microwave (HPM) weapons. The first type is the conventional RF weapon, which sends a concentrated band of radio waves toward a target. These radio waves act similarly to the waves inside a regular microwave oven; given enough power, they can be used to heat and damage electronic equipment operating at the same frequency. Because of this need to match the frequency with the target, conventional RF weapons require preliminary research and intelligence before they can be effectively deployed by terrorists [3]. A second, more insidious type of HPM weapon is what Shriner calls a transient electromagnetic device (TED). ). Instead of producing a sine wave at a particular frequency (as conventional RF devices do), TED creates a sudden spike in energy that can last up to 100 picoseconds (the amount of time it takes for light to travel approximately 1.