“Stealth” Drones. How can a drone be “stealthy” if it must be constantly transmitting data in order to be remotely operated? Isn’t radio silence a requirement for stealth in the modern battlefield?



“Stealth” Drones. How can a drone be “stealthy” if it must be constantly transmitting data in order to be remotely operated? Isn’t radio silence a requirement for stealth in the modern battlefield?

In: Technology

Stealth aircraft (planes, drones, etc) means it’s “invisible” to radar. Through means of material and or design to absorb and or reflect radar.

So the radio and or computer signals would not be what makes or breaks an aircraft from being stealthy or not.

Radio transmission can be directional. If you put a directional antenna on a drone and direct it to a satellite it would be close to impossible to detect it from below the drone. You might have a chance from a aircraft close and above the drone but that is hard to do

Transmission to the drone do not need to be directed to it bout could cover countries or continents and if they are encrypted the would not help in detecting the drone.

I would be easier to intercept if you had electronic intelligence satellite in the correct position in space but they are rare and few countries have any.

It’s very hard to pick up straight em emissions of any kind (radio like you said for example). You don’t know the frequencies, polarization, or anything that would help you find the electromagnetic transmissions in the vastness of the spectrum.

Several ways to do that.

The easiest is to not transmit, just program it with “Follow this path, record everything, then go back home so we can look at it.”.

If you need realtime data, you need to transmit. It can be done through very directional antennas. Of course, that is risky, because it’s easy to lose contact. It can use fancy techniques such as frequency hopping and burst transmissions. So, they send data in very short bursts, and between each burst, they change frequency according to a secret schedule. This makes it very hard to snoop on or triangulate any locations. ELI5-version would be to compare it to having a shitload of telephones at each end, and use a new phone for every word you send. That would make it very hard for anyone to snoop on, as they don’t know which numbers to listen to, and it’ll all be very chopped up.

Either way, expect heavy encryption and verification protocols.

Theres a concept known as Low Probability of Interception where the radio or radar is made to be hard to be detected.

One way is to jump around on different frequencies at a high rate of speed which makes finding the signal hard, another is low power and also irregular transmission lengths.

They try to make it look like noise that doesn’t seem like a coherent signal

In addition to what was already said, dont forget that you can have the drone operating semi- or fully antonomously., alternativelly it can have a designated area of such mode of operation.

This can mean that there is little radio traffic.

In theory tou could also use point to point comms, like a laser line, as well. Tho I dont know if any operational drones use that.

I don’t know if this is done, but another idea could be to use light. There is no way to sniff that. But with the resolution of current gen keyhole satellites and a stealth drone with known flight path a light signal could be used to morse code some information back.

Stealth doesn’t mean being invisible all of them time. It means being hard to detect in the right ways at the right times. If you expect the no one can do anything about your transmissions then broadcast away.

If someone can take advantage of detecting the transmission there are a number of things you can do. Maintaining stable flight is a well understood problem, the drone can do that on its own. So the operator doesn’t need constant feedback in order to control it.

Whatever you do need to send can be sent in a directional broadcast rather than in every direction. That means the listener must be in the right area (or have extremely powerful equipment) to even have a chance. Having those be quick bursts of data rather than a sustained thing makes them harder to pickup and locate. You can also switch frequencies constantly, making ot likely that anyone listening will miss some of them. The drone is also constantly moving so even if the listener gets the information they need it might be out of date. Encrypting the data also helps since encrypted radio should sound similar to static, making it harder for a listener to be sure they’ve found a real signal.