I don't mean that air-based drones will be useless, I just think they're going to see more constrained missions than we might currently be imagining. And I do mean just the common conception of drones... things arguably properly described as "autonomous planes" will continue to be important and will probably continue to grow both in importance and in physical size.

This isn't really for drones. It's for frying ground-based electronics like cell phones. Drones are the smoke screen to hide that fact.

As for drones, motors and batteries are quite hardy against quick microwave pulses. A bit of aluminum foil makes a good, light Faraday cage. Optocouplers can isolate radio and GPS modules from the actual motor control systems.

I would expect you can fry an RC drone, but an autonomous one operating inertially or capable of switching so when radio/GPS goes away is probably pretty easy to shield.

In addition, this kind of system is always going to have a range vs width tradeoff. Can the drones get inside this thing's range where they can still be effective even if they are "ballistic"?

Dumb old bombs are really effective if you just give them a little bit of GPS to improve their accuracy. You don't have to get very close for the GPS adjustment to be devastatingly effective.

Or imagine a smaller system integrated on a humvee that can destroy electronics in anything along the path a few dozen meters in front and in a smaller side/side area. That'd end the IED threat from anything other than a purely mechanical IED (not sure if many of those are around anymore, as everything assumes electronics will work nowadays).

This is why IEDs are so effective in asymmetric warfare. They are cheap and anyone can get parts =(

The first time I saw the results of an IED blast was a day after I arrived in Iraq. I had to shake a tree in order to retrieve the trousers of the guy who blew himself up planting the thing. That happened a lot. Making IEDs isn't very hard, but making a lot of them without eventually blowing yourself up is.

Now a much better thing to do instead of making IED drones would be to melt sand or rock into appropriately formed projectiles so that one has an autonomous artillery piece that does not require reloading.

There are much better explosives to use than hydrogen. One could use the haber process to make ammonia and use some biological carbon sources to make pretty much any explosive worth using.

Landmines are probably cheaper though.

While I agree with the idea that there will be more fun ahead with ground-based drones, wouldn't an air-dominance doctrine still hold in drone-drone warfare as it exists today in conventional wars?

I imagine both ground and air drone warfare evolving at similarly terrifying rates over our lifetimes.

The US relies on air power tho if you look at BDA imagery released not a small percentage of the so called drone strikes are more likely than not to have been conducted by mannned strike fighters as drones can't carry things that would leave that big of a crater.

If you're thinking about RF, then frequency doesn't matter that much. It's just that absorption and penetration slowly change with frequency, that's all. There are no "deadly frequencies" there.

If you're thinking about modulating the RF with some signal matching the heart rate or some brain waves, that's... interesting, but I'm not sure if it has ever been proved to work.

https://en.wikipedia.org/wiki/Radiation_burn

At frequencies near the body's natural resonant frequency, RF energy is absorbed more efficiently, and maximum heating occurs

http://www.arrl.org/rf-radiation-and-electromagnetic-field-s...

>There was this French bloke at the turn of the 20th century who built a giant whistle that produced sub-bass frequencies of around 7.1 or 7.2 Hz. The first time that he got it to work, he liquidized himself. It just turned his insides to mush—poor bugger.

http://djtechtools.com/2014/04/10/funktion-ones-tony-andrews...

Then run a simple optical fiber cable for communication to an antenna that lies outside the cage.

If you are really good you have multiple antennas that are kept off (with the circuit physically disconnected from the antenna). If you get hit with a pulse activate the next antenna.

It's possible to make simple electronics that can survive such a pulse, with auto-reset fusible links, and you use those for activating the antenna.

Or even a small door and "push" the antenna out of the Faraday cage when needed.

Drones carry their own power source - usually a LiPo battery.

What you're proposing would not work if the phaser could just keep firing (which seems likely). Onboard AI seems the solution (assuming the Faraday cage is effective enough, which remains to be seen).

You misunderstood me. Use that to provide power to the antenna which is outside the Faraday cage, and the battery is inside.

> What you're proposing would not work if the phaser could just keep firing

The phaser has a range though. So program the drone to fly up and away if it gets hit (no need for AI to do that). Then reactivate communication and stay away from the phaser area.

Source: I flew UAVs "drones" for the US Army for 482 combat flight hours in Iraq. Lookup the wikipedia for "Ground Control Station" for an old pic of an 18 year old me @ the UAV training center "black tower" in Ft Huachuca, AZ.

This is a problem as microwaves are in the centimeter range. The mesh then would have to be dense. That would raise aerodynamic issues.

I'm not saying it's not doable. I'm just raising the obvious concerns about basic challenges from the laws of physics.

Two real issues with massive RF energy density:

1. Penetration depth. Even if you have a continuous metallic bubble with no holes, some RF radiation still leaks inside, depending on material nature, thickness, frequency, etc. The amount is small, but it's not zero.

2. If energy density in the RF beam is huge enough, the shield / cage starts heating up. You could conceivably melt it if you take this game far enough, or poke holes in it.

With regard to #1, I agree, but the degree of RF leakage is not universally small - it depends on the frequencies you encounter and the properties of your cage (material, mesh thickness and "pore" size, etc). As frequency increases (and wavelength decreases), your pore size must decrease to effectively block it, eventually becoming a solid shell (through which propellers will, of course, generate no thrust). I agree with #2.

No. In a conductor, all free charges migrate to the outside surface.

Heck, all the wires, electronics, and motors could be inside the "arm". Then coat that with some EM shield material (like a metal foil).

I like it.

Of course, from "like it" to "it's actually effective" there's still the nagging little field test to perform. It's the old shell-vs-armor game, since EM radiation has a penetration depth - Faraday cages are not magically 100% effective, make a thin enough one, and a powerful EMP would still do some damage inside. So now you need to carry thicker, heavier EMP armor.

However it also means the drone has no GPS; no wireless signaling; no sensors outside the foil at all. It becomes a dumbfire dead-reckoning device.

No, they are not. Even a continuous, zero-hole metallic bubble will leak some radiation inside, depending on frequency, nature of material, wall thickness, etc.

Start here:

https://en.wikipedia.org/wiki/Penetration_depth

then continue reading about absorbance, skin effect, etc.