Why can’t drones be designed to home in on and destroy jammers?

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If I understand correctly, a jammer puts out a bunch of RF to overload a drone’s remote link or GPS signal. Why wouldn’t it be trivially easy to just home in on that transmitter and destroy it?

In: Engineering

17 Answers

Anonymous 0 Comments

They can be, they’re called anti-radiation missiles.

They’re more expensive than off the shelf consumer drones though.

GPS jammers might be a bit tricky, just because it takes very little power to disrupt, on account of GPS signals being extremely weak to begin with.

Anonymous 0 Comments

These have been a thing since WWII. They are often pretty complex to use and make. And expensive. And plenty of other layers of defense against them. These types of weapons and electronic warfare systems were obvious to people 80-90 years ago.

But most advanced militaries have these capacities in various forms.

One issue with small drones is that they are small and cheap. That means they often can’t carry the equipment needed to do these tasks and it would make them much more expensive. They also may not be able to travel the distances needed to strike the systems which are often far behind the front lines

Anonymous 0 Comments

The US military has been doing that for decades.

The Shrike and HARM missiles work on this principal for enemy radars.

I wouldn’t be surprised if they have built drones that operate on a similar principal, or at least have them on the drawing board.

We don’t hear about a lot of this stuff because it would be classified. But if it’s an obvious solution to a battlefield problem… chances are they are already working on it.

Anonymous 0 Comments

Semi-related: During WWII the Germans developed a radar receiver which warned submarines that they were being lit up by airborne radar.

All of a sudden subs were being bombed without their detectors going off. A captured British airman was interrogated about this, and he told the Germans that the brits had developed a system which homed in on the radar receivers.

The Germans sent out panic messages to all subs to stop using the receivers.

In reality, a new frequency of radar was being used, but the airman was celebrated for creatively causing a bit of extra panic.

Anonymous 0 Comments

Others have noted that there are weapons designed specifically for this, but also bear in mind that jammers

* can be mobile
* can easily be turned on and off if there’s a threat detected (or just at random intervals)
* can be part of a network of multiple jammers

If you add in the possibility that the enemy can track threats and respond by turning jammers off and on, then your attack becomes orders of magnitude more complex.

Basically when you’re thinking about military tactics and asking a question like this, the answer is usually to assume that whatever you’re thinking of is possible, but to then imagine that if you were on the other side (“How do I protect my jammers from attacks using the signal to home in?”) and keep going back and forth. Often you’ll see that for specific scenarios the cost of a given strategy would be way more than the cost of countering it.

The obvious example I always think of is the [Strategic Defense Initiative](https://en.wikipedia.org/wiki/Strategic_Defense_Initiative) or “Star Wars” program that was supposed to create a defense against ICBM delivered nuclear weapons. It got lots of hype, and I’m sure lots of defense contractor employees retired off the pork fat that it generated, but the problem is that the cost of developing it would always be orders of magnitude to the cost of creating countermeasures to bypass or overwhelm the defenses.

Anonymous 0 Comments

They could.

The issue is that we are getting used to faster and faster development of new tech, and now we want it instantly.

It takes time to develop the specific tech.

We have stuff for homing in on older radar tech. We need to tweak it a little for low intensity signals.

Anonymous 0 Comments

There is tech that will zero in on the tracking or jamming signals and destroy it, but you’re wasting ammunition and resources on something that probably wasn’t the original target anyways. Even if the jammer is destroyed, it succeeded in protecting whatever was the original target

It’s cheaper to improve the drone to make it resistance to jamming. Adding a thin piece of metal will shield it from below attacks, directional antennas to limit jamming exposure, and even the ability to jump frequencies and channels can make jamming unreliable.

This is kind of way one of the best counter measures against drones is starting to become drones that can disable enemy drones in midair.

Anonymous 0 Comments

OP, you’ve got a great question there.

The problem is relative signal strength. The drone creates a ton of noise by running 4x ESCs and brushless motors. It may broadcast on 400mhz ,900mhz, 1.2, 1.5, 2.4, 5.8 ghz. God only knows what other bands are running up there right now.

The signals on the bird will interfere with its ability to home in on another signal at range, even if it’s a very strong signal. Remember that received power is the inverse of the square of distance. When distance is zero, the signal is very strong, even if it really isn’t strong in absolute power.

To combat that, you’ve got to get the RF transmitters off the bird and quiet it down a bit. That means 1 ESC not 4, or better a nitro engine that runs like a diesel, not electric or magneto powered. No video transmitter. No RC input. Shielding on the GPS system. Shielding on the computers. Then, because you have a fixed wing, you can incorporate antennas into the wings for receive.

The original shrike seeker could probably fit on a 10 inch quad if you could power it. The questions then become – is your bird fast enough to make a difference? Can it carry enough bang to make a difference? Is it better to power that whole package with a rocket, than a propeller?

An anti radiation drone is intriguing. But I think fitting it to existing guided surface to surface rockets would be more effective in the short term. The thing that gives drones their power isn’t their flying capabilities or speed. It’s the fact that there is a human flying and interpreting data from the drone. Best guidance system there is…

Anonymous 0 Comments

FPV kamikaze drones are based on civilian tech. They’re really quite ‘dumb’ beyond the attitude control features and don’t have directional sensing antennas. Lots of the kamikaze ones don’t even have GPS.

What you’re looking for exists, but it’s called an anti-radiation missile. They can sniff out what way to fly to hit the radiation source.

Anonymous 0 Comments

Drones can’t easily home in on and destroy jammers because jammers spread their signal over a wide area, making it hard to pinpoint their exact location. Plus, jammers can be mobile and quickly change positions. Additionally, the jamming signal itself can interfere with the drone’s ability to navigate and communicate, making it difficult for the drone to operate effectively. So, while it sounds simple, the technical challenges make it quite complicated.