NC Scout at American Partisan has started a series of articles on antenna theory called Directional Antennas for the Small Unit. If you’re just getting started in radio communication, or you’ve been using it for a while but haven’t spent much time getting to know your antennas, this is a good start.
One of the biggest misconceptions behind communications security revolves around misunderstanding not just the role of the equipment but also how it functions. A big part of that is the basics of antenna theory. For most radio seems to be a plug and play kinda deal- it either works, or it doesn’t. Antennas are a type of voodoo magic and the solution to security is electronic encryption. Except it isn’t, and doesn’t do anything except mask what you’re saying, but not the fact you’re saying it. Guerrillas must rely on not being detected- and no matter how high tech you think you are, it’ll not solve a tradecraft issue.
The reality is that we’ll be working with equipment that is common and off the shelf- no matter how much we want those microwave NSA-encrypted troposcatter radios made of unobtanium, a big part of local networking is done via plain old VHF and UHF amateur and commercial gear that’s common. Guerrilla communications have to be harder to detect. And at the strategic level when building an underground network, you have to understand how to plan. Even with the cheap equipment most of you likely have, incorporating a level of planning into your local communications will yield a much higher level of security and success. Knowing and understanding directional antennas becomes a key part of that planning, and as we cover in the Advanced RTO Course, there’s several options that each get the job done.
Directional antennas accomplish two goals for us. First, generally speaking, if you’re not in the direction of the transmission you’re not going to hear the traffic. Because of this it offers a big advantage in the security department. If two directional antennas are transmitting toward one another, they’ll be able to communicate with the only people hearing the full conversation being in the middle of the two people. The second advantage is that instead of all our energy going in all directional at once, as with an omnidirectional antenna, a directional antenna sends the same amount of radiated energy in one direction- greatly increasing our range and signal strength in that direction, so we won’t need nearly as much power to accomplish to reliably communicate over a distance you might not have thought otherwise possible…