How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet of drones | Hacker News Reader

How the U.S. Army’s ‘Phaser’ can wipe out an entire fleet of drones

saintlad.com

96 pointsjakekovoor111 comments

Wonder how many watts that thing is putting out, and at what frequencies. In theory it could kill a person if it pulsed the correct harmonics. Will be interesting to see drones with Faraday cages. Some teenager on YouTube did something similar:

https://m.youtube.com/watch?v=DoOT2_Z-GIE

Looking ahead to the next 20-30 years of warfare, I've often thought that despite the fun we're currently having with aerial drones, a lot of the real drone future is going to be with autonomous ground drones, because of their ability to carry more armor, shielding, etc., without having to literally carry it into the air. Our current conception of a "drone" is really hard to bring up to military spec once this sort of countermeasure becomes militarily common.

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.

> Our current conception of a "drone" is really hard to bring up to military spec once this sort of countermeasure becomes militarily common.

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.

> 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.

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).

Nope, insurgents found a way around that a long time ago when convoys started including jammers. Hybrid detonation systems: radio arm the device outside of jamming range, mechanical switch detonated the IED once the vehicle triggers it.

When my brother was doing Op-For at camp Irwin he used one of the sensors from a garage door for simulated IEDs. Pressure plates, lasers, motion sensors, you name it and it'll make something go boom.

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

I assume you're talking about the safety beams that prevent the door from closing on obstacles. Have you ever had the door go down on command and then halt, without any obstacle in the way? They're very noisy sensors - lots of false positives, not the sort of thing you want to wire up a massive bomb. They also actively emit light, so not very stealthy.

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.

Or they simply use long wire buried in sand.

I only saw that a couple of times, in one case we caught the guy - he still had the 9v in his pocket (why he'd keep it I don't know). If you watch their videos you see that they prefer to be much further back than what is practical with a wire commanded detonation. There were rumors of laser commanded detonators, but I doubt it happened enough to warrant any sort of countermeasures.

Imagine - a mobile drone factory, digging itself in in the hinterlands, harvesting solar energy and water, producing mobile hydrogen-IEDs - the minefields of the future will be hard to undo.

Does that sound like a paperclip optimizer? Because it certainly looks like a paperclip optimizer. Think of it: eventually humanity goes extinct because the whole world is land mines...

Well if it's solar powered, we can easily take it out with an inexpensive sticky black paint bomb. Second, while you won't run out of water, you will run out of other stuff for your hydrogen IED drones.

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.

This is pretty much the premise of Philip Dick's Second Variety, made into the movie Screamers.

Thanks for the tip. I didn't know that one had any kind of movie adaptation.

Screamers is surprisingly underrated. It's one of the best pop-sci-fi movies from nineties imho.

The ending to that story was particularly delightful.

arms race has it all taken care of - in response to autonomous IED making drones there will be autonomous drones clearing up the minefields and hunting down those IED making and installing drones. Of course to deal with the hunter drones the IED making/installing drones will have special protector drones ... Humans just need to relax in the deep soft chair and enjoy the popcorn.

>>I've often thought that despite the fun we're currently having with aerial drones, a lot of the real drone future is going to be with autonomous ground drones, because of their ability to carry more armor, shielding, etc., without having to literally carry it into the air.

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.

For someone who has been out for a hike and been startled by a rattlesnake a step away, I can imagine a terrifying world of small, ground-based area denial robots that spring to action faster than our reaction time can avoid them.

Like a mine with a brain.

As scary as that sounds, I feel it is better than the mindless landmines laying around from past wars. In theory, when the war is done you could hit the disarm or recall button unlike conventional mines.

Unless the drone mine gets hacked. It might even have a protocol to shield itself from a fuel-air bomb, which is a common form of mass-mine detonation.

I've never heard of a fuel-air bomb used for demining... APOBS is used a lot, and no matter how clever the mine is - it can't ignore a chain of explosives going off on top of it.

It's not objectively the best Sci-Fi I've seen, but I have a soft spot for Crichton's film "Runaway" which has some of that in it.

The Russians are focusing on ground based combat drones almost exclusively. Their air drones seem to be geared toward surveillance.

Because Russia's war will be next door and on the ground.

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.

I think you're right. Once you factor in high efficiency solar panels (like the germanium ones in satellites) land based drones can infiltrate enemy territory and sleep for months or years until they're needed.

Sleeper photovoltaic cells?

For the next 20-30 years, drones will be built to fly above the range of such weapons and remain extremely effective.

No they won't there is an upper limit to flight and if by some means these drones would be closer to space than to the ground you put those weapons in space or on high altitude tethered platforms.

> In theory it could kill a person if it pulsed the correct harmonics

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.

Frequencies considered especially dangerous occur where the human body can become resonant, at 35 MHz, 70 MHz, 80-100 MHz, 400 MHz, and 1 GHz.

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...

I stand corrected, I forgot about resonance.

Thanks for those.

Having trouble trying to understand how what I read fits in, but the guy who designs those massive mega wattage sound systems for festivals - Funktion1 - commented in an interview about how there are, essentially, lethal sound waves of sorts.

>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...

With a drone encased in a full faraday cage, how would the operator control it? Therein lies the problem unless it was preprogrammed and fully autonomous. That might work.

Faraday cages don't block DC, so use that to provide power.

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.

> Faraday cages don't block DC, so use that to provide power.

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).

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

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.

I think this is an expensive solution, which would increase radar cross signature almost certainly. Also, it would protect against a weapon that isn't fielded while doing nothing for any conventional weapons.

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.

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

Yeah. The solution is likely more along the lines of making the drones cheap and disposable, and fighting these systems with traditional air defense suppression.

Very much agreed. I see this "phaser" system as a neat tool that could work along side conventional anti-air such as Patriot batteries to make it pretty difficult to gain air superiority.

One thing about the Faraday cage is that is has a maximum frequency - when the wavelength becomes comparable to the cell size in the wire frame. Any higher frequency will just go through.

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.

Wouldn't a large amount of targeted RF incident upon an ungrounded faraday cage induce a large enough charge accumulation to also pose a threat to the drone (and anything around it)?

It's not ionizing radiation. Even if it did that, with a metallic shield on the outside, any amount of static charge on its surface generates zero field inside - this is a perk of metallic shielding.

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.

There is a net zero electric field inside, true, but isn't that because a charge accumulates on the inside surface of the cage that is equal and opposite to that induced on the outside surface?

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.

> There is a net zero electric field inside, true, but isn't that because a charge accumulates on the inside surface of the cage that is equal and opposite to that induced on the outside surface?

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

You could put your propellers outside and away from the cage, with their motors inside the cage. This would also greatly reduce the size and weight of the cage.

That might work. The "cage" would be more like a sleeve in the region of the arm - just creeping out on the arm like a mesh tube (or even continuous foil tube) to protect the wires, electronics, and motors. A small hole would allow the motor hub to stick out of the cage, and the prop would be on top of that, outside the cage.

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.

I think they are magically 100% effective. Unless the cage is breached, nothing will get through. However, an EMP pulse could melt holes in the foil.

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.

> I think they are magically 100% effective.

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.

I see. Only for zero-resistance metal would skin depth be zero.

At microwave frequencies, skin depth is essentially zero (microns anyway) for most metals. So until the bag is melted, nothing will get through.

You don't need a full cage. As the beam can only originate from the ground you can just shield the vulnerable bottom half. Don't see how this weapon can work against sophisticated adversaries.

Ground based targets is part of the scope for the weapon - just mount it on a plane (maybe a large drone!)

Good luck with getting GPS then.

Place the receptor outside of the cage, put a resistor and a biggish capacitor, a varistor and a fuse on the communication line, and it's good enough for any disposable machine.

With a good enough AI and a detailed aerial map onboard, you may not need it.

Line of sight lasers are one possibility, but those are vulnerable to dazzlers.

I always thought a Faraday cage had to be grounded but after a bit of reading I think that is not actually the case.

Whoever in the military writes the descriptions for these things has got to be so excited that microwave energy moves at the same speed as light, just so they can say engagements take place "at the speed of light"

Most of the time you see phrases like that, they've been added because many of the decision makers in charge of the DoD and above (think Congress) are not experts or even particularly knowledgeable about the underlying technologies.

You don't need to be an expert, people learn about optics and EM in 7-8th grade science classes if not earlier.

If they don't fix your education system.

Come on, we're so close to this:

http://battlefront.wikia.com/wiki/Hoth_Dish_Turret

This drone can operate underwater and takeoff into the air. It has a metal fuselage where almost all the electronics are contained, including the autopilot. The only thing exposed is GPS, antenna, and motor. It would survive if operating underwater. I wonder how it would fair in the air.

https://www.youtube.com/watch?v=Aw01NnG9hu0

Wonder if drones could be shielded against this? Or, better yet, could the technology be adapted to transmit energy to drones or spacecraft?

Of course. Wrap the drone in a Faraday cage. It will need to be capable of flying itself and communicating with lasers to work properly.

There has to be a better article than this one about this weapon.

Wouldnt this work on standard jets and tanks since they're all fly by wire these days?

So it doesn't work on drones wrapped in tinfoil?

EMPs are all well and good, but wrapping the important innards of a drone in conductive foil is not difficult. No matter how big that generator, the actually energy transferred to a drone a few hundred meters away will be tiny. Imho a few nods towards EM hardening in the drone's circuitry would not add more than a few grams. They talked about this for air defence back in the 80s, but the metal-skinned aircraft of the time would be totally immune.

what is the effective range of this? 'drone' can mean a lot of things, and knocking out a 20 lb quadcopter is a little less impressive than a global hawk five miles up

The article says the Phaser uses a combination of EMP and high-powered microwaves. Are those meant to be different in some way?

EMP is a burst of noise. You could make it with an explosion, or via the undisciplined discharge of a large capacitor into a semi-resonant circuit. It pumps energy into a broad spectrum. It's hard to contain it in a very specific direction, although simple reflection techniques, etc, could be used.

High-powered microwaves are like a microwave oven, or a radar, except more powerful I guess. Could be focused in a specific direction with ease. It usually works at one main frequency, or a small set of well-defined frequencies.

EMP, or pulses, are broadband. Take the Fourier transform of a short (~ 1 nsec) pulse and you'll see significant energy up through several GHz.

In the EW environment, broadband pulse radiation can couple to slots, wires penetrating a Faraday shield, joints in the Faraday shield - really, a wide range of electrical discontinuities that act as receiving antennas if you hit them with the right wavelength. This lets you put HV pulses into sensitive circuits without knowing much about the target. Pulse countermeasures require more expensive engineering and fab.

The system described may also have a continuous (microwave) capability for threats they know something about. If you know that $yourfavoritedrone has particular electrical resonances in its antennas, motor leads, or whatever, you could emit on those resonances and induce high voltage on those structures.

Anyway, that's what I think they mean - this is both a pulse and CW emitter.

Suicide drones which zoom into the jammer source (like a HARM missile basically)?

Why can't you just wrap your drone in aluminium foil around the outside - I don't mean the top and bottom, you need the top and bottom open for air flow.

Wouldn't aluminium foil stop that microwave?

It wouldn't be that easy. The drone would still need EM windows for its other requirements, possibly communication and navigation.

Is there a large current threat of enemy drone armies? Because I thought most of our last two wars were fought against loosely organized militia fighters and IEDs.

Like the article mentions, ISIS and other bad guys do have drones (think DJI Phantoms, not Predators). ISIS even uses drone footage of attacks for their propaganda videos. I saw a report from a journalist following around Iraqi special forces retaking Mosul. At one point an Iraqi officer pulls out his iPad and a DJI controller to fly around and gather intelligence. I'm sure ISIS does the same. It was a little unsettling to see things that I considered fun gadgets/toys used for warfare.

Many of those threats are technologically solved and the improvements will be iterative. Our R&D needs to focus on projected future threats.

Also, our last two "wars" were no real threat to our country. We don't need directed energy weapons and stealth submarines against jihadists, but we might against Russia and China.

Do you think that 15-20 years from now nearly every nation won't have military attack drones of varying types? The military would be crazy to not build / R&D new weapons for where technology is moving rather than where it was decades ago. It's simply skating to where the puck is going to be.

> the U.S. Army’s ‘Phaser’ can ... take down ... anything with circuits in a single shot ... iPads, computers, targeting systems or even cars speeding toward checkpoints.

You know how they say "Generals always fight the last war"? Presumably this and other advanced technologies are an attempt to make sure we fight the war that we end up being in.

If you can take out an enemy vehicle before it gets to your checkpoint, then suicide bombers and other forms of guerilla warfare will become obsolete since they will not have sufficient enough range. As it is, they rely on more primitive technologies since they are less cash rich but now their weapons that don't have circuit boards will be more effective. Intelligence and espionage will still be more useful than firepower directly.

IS is already using commercially available drones as weapons

http://www.nytimes.com/2016/10/12/world/middleeast/iraq-dron...

I believe it'll largely depend on who we have our next war with. If it's with a first world nation then more sophisticated air support should be expected.

What I'd like to know is if this is relying on drones (either multirotor or fixed wings) having carbon fiber or plastic bodies as opposed to enclosed metal.

It's a lot more effective to kill the circuits.

Sure, carbon fiber is conductive, but the energy involved to fry the CF booms is orders of magnitude that required to just zap the flight controller.

I think he's suggesting that the carbon fiber is much more RF transparent than metal.

Yeah, didn't really have time to flesh this out, especially if it's carbon filler material vs. continuous. I haven't worked enough with CF to know what its shielding effectiveness is but I imagine given the size of that Phaser that this thing will be trying to blast through some stuff.

Oh, I see.

Penetration depth depends on resistivity. A superconductor has a penetration depth of zero. A real material, it's non-zero.

Carbon fiber is conductive, but not as good as a metal. Therefore I would expect penetration depth to be quite a bit bigger with CF. So, perhaps it's not a good idea to rely solely on CF for shielding.

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

Carbon fiber is conductive.

> What is high-power microwave (HMP)?

> I am sure you have a microwave oven in your house and I am going to believe that you do know how a microwave oven works. If you don’t know, then go ask your mom.

This is a strange assumption. I'm pretty sure most moms I know don't know how they work. Is this really commom knowledge?

I'm pretty sure my mother knows how a magnetron works and she's not an engineer. It's not like it's a secret!

I think we watched a YouTube video on it as a family a few months ago and I'm still confused.

These will be important in the impending AI wars.

Impending? I think you mean ongoing. Here is the latest news from active battle sites:

https://what-if.xkcd.com/5/

I am sure the developers are thinking shield, but that thing is just going to be an easy target. Remember this would be useless vs. missiles and it can't hide.

It wouldn't be sent out on its own to disrupt drones. It would be part of a group with defensive and offensive capabilities. Also, this is proof of concept. A deployed version would probably include increased armoring for the power plant and control.

It suffers from the same problem as Radar anything that needs to broadcast is easy to hit. Awacs aircraft for example are an evolution of this concept.

The first obvious solution is to have a separate unmanned 'pod' that's easy to replace. But, a manned and self contained truck even with armor based on this design would be a really dangerous place on a battlefield.

That's a good point. If the radar is a brief pulse that would help. Staying mobile would also help. An unmanned expendable perimeter pod, like you suggest, could also draw fire.

Why couldn't a missile be fried in a bath of Microwaves like a drone?

First off they don't call it anti-missile, which should be a strong hint.

But, vast differences in speed, already being hardened vs. EMP, aiming to hit the vehicle vs. stay in the area, inverse Square Law, and not being RC controlled are all rather important.

PS: Like a lot of things, if this where 10,000x as powerful then it would be a different story.

Why is High Power Microwave "HMP"?

The Scientific American article linked in the article actually uses "HPM" throughout, but it also mentions a "high-powered microwave pulse", which I imagine is what "HMP" actually refers to, analogous to EMP.

Can we just blanket every ISIS controlled region with some of this microwave energy and send their communications ability back to the stone age?

You might end up cooking a lot of people, as well as disabling all of the surrounding infrastructure, sending the people who live there back to the stone age as well.

"We cleared out all those ISIS bad guys for you. Well, their cellphones. You probably didn't hear about it because we also cooked your cellphones and radios, too."

So the innocent people inside have literally no hope of communicating with the outside world?

You mean a neutron bomb.!

Maybe we should figure out why they fight and not bomb the crap out of them or send the back to the stone age (BTW, people living in the 'stone age' knowing there is something better will fight for that)

You think figuring out why they fight matters? I have not seen any evidence that getting involved in the Middle East has ever been a long term win for both sides. Best thing the West can do is leave it alone (that includes not selling arms to various involved parties, which is currently happening in many countries over there)

Reply on news.ycombinator.com