Radio Frequency Weapons and the Next Phase of TerrorismSummary: This article examines different types of radio frequency (“RF”) weapons currently under development. It examines 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 floated the idea of ​​the “RF weapon,” something that has been described as if it were a magic weapon capable of bringing the United States to its knees. Although these weapons exist, the threat they pose is far less widespread and dangerous than articles such as “RF Weapons Attacking Our Freedom?” to propose. That said, 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 that between RF weapons and EMP weapons. An EMP (electromagnetic pulse) is typically used by detonating a thermonuclear device at high altitude (500 miles or more) above the Earth. The resulting electromagnetic pulse paralyzes any electronic equipment in its path. Thus, a single 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 it can cause just as much damage [2]. According to David Shriner, a former military engineer and RF technology expert, there are a number of different 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 in the same way as the waves inside a normal microwave oven; with sufficient power, they can be used to heat and damage electronic equipment operating at the same frequency. Due to this need to match the frequency to the target, conventional RF weapons require prior research and intelligence before they can be effectively deployed by terrorists [3]. A second, more insidious type of HPM weapon is what Shriner calls the 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 as little as 100 picoseconds (the time it takes for light to move). 1.