Can Drones See Through Walls?

While drones are revolutionizing industries left, right, and center, they come with significant issues we can’t ignore. One of the main issues is privacy infringement.

Initially, people were only worried drones could hover over their place and spy on their compound, which they can, but some laws can now prevent that.

With technological advancements, we now have sensors that can see through walls, and these sensors can be fitted in unmanned aircraft.

This brings up the question, can drones see through walls?

The consumer or prosumer drones you see doing photography, mapping, or inspections can’t see through walls. However, a drone can carry a device that intercepts Wi-Fi and uses the devices in your house to spy on you.

Should this cause alarm? Let us find out. 

Can drones see through walls? #

Most of the drones we have today are designed to take photographs and videos from a distance. As such, they can record an image from some meters away, especially if they have powerful zoom lenses, but they are not strong enough to see through walls.

However, we should also consider what your walls are made of. If you have glass walls, any camera with a good resolution and powerful zooming will see through them, but they may have to come closer to your house.

For concrete walls, you should be safe.

There are exceptions when we look at how drones are used in the military, emergency response, or research and development. Let’s look at each of these in detail.

Drones with thermal cameras #

Infrared or thermal sensors are designed to detect people or objects not visible to the naked eye.

You can use them for night vision, or in this case, if they are powerful enough, to detect what is behind a wall.

Now, they will not give precise details, but the user will be able to tell how many people are in the house, where they are, if they are armed or not, other objects in the house, and even the general layout of the room.

Drones with such sensors are used in the military, rescue operations, and even in agriculture and inspection where the data that needs to be gathered is not visible to the naked eye.

Let us take a case where a story building has collapsed. How do the rescuers know if they have rescued everyone stuck there?

Also, think of a case where some prisoners have run away from prison and are hiding in several buildings. How do the police know which buildings or rooms they occupy?

A drone with a thermal camera and an excellent zooming lens will come in handy.

Below are some drones that come with thermal cameras or can carry a thermal camera as an extra payload:

• DJI Mavic 2 Enterprise
• DJI Mavic 3 Thermal
• DJI Matrice 30T
• Autel EVO II Dual 640T Enterprise
• DJI Matrice 300 RTK
• DJI Phantom 4 Multispectral

Drones that can see through walls using Wi-Fi #

Now, there are two ways drones can see through walls using Wi-Fi. Let’s take a look.

Intercepting your home’s devices #

Ever heard of cases where hackers can hack into your Wi-Fi when they park a car close to your house or rent a house in an area close to your house? Now that’s possible with drones.

Researchers from the University of Waterloo developed a device called Wi-Peep, which exploits Wi-Fi vulnerabilities to access devices connected to the Internet.

This is an indirect way to see into your house since they could spy on you through your webcam, CCTV, and any other device with a camera in your house. 

If it can’t access the camera, perpetrators can also use it to locate people, such as security guards, within the room based on the devices they have on them.

They can also use it to locate devices such as TVs, speakers, refrigerators, and any other device connected to Wi-Fi when one wants to steal them.

Now, this is a device you should be worried about because it only costs about $20 to build it. Anyone with the expertise and the means can create such a device, mount it on a drone, and spy on your house.

A more complex system was even used to attack a finance firm, steal staff’s login credentials, and attempt to infiltrate the company’s system remotely.

All this was done by landing two drones, a DJI Phantom and a DJI Matrice 600, fitted with the system on the company’s roof.

 3D modeling #

An experiment conducted by a student and a professor of the department of electrical and computer engineering at the University of California showed that you could model the interior of a concrete wall using Wi-Fi only.

Yasmin Mostofi (the professor) and Chitra Karanam (the Ph.D. student) developed a system where two drones were fitted with Wi-Fi transmitters. These UAVs were then allowed to fly around a concrete structure along a predetermined path.

The technology they used is RSSI (Received Signal Strength Indicator), where one drone sends the 2.4-GHz Wi-Fi signals, and the other receives the signals and records them.

As the signals go through the structure, they behave differently, allowing them to develop a profile of the house’s interior.

The video below shows the results of their experiment.

As you will see in the video, this system works, but it’s not that accurate, and the users will still have to do a lot of guesswork to tell what’s in the room.

Keep in mind that it’s still under development.

Radio wave system to see through walls #

This more advanced system seeks to use radio waves to compensate for the areas that are lacking in infrared and Wi-Fi.

Dr. Zheng Wang, an Associate Professor at the Leeds School of Computing, explained that infrared could only detect heat signatures. So if the house occupants found a way to block their heat signatures, a thermal camera would be ineffective.

Instead, this technology uses short-range antennas to send signals. These short-range antennas are designed to mitigate interference as much as possible.

Once the signals are sent, they bounce off of objects on the other side of the wall, just like radar works, allowing the user to map and identify what’s on the other side of the wall.

However, it has its limitations. It is only able to identify people or objects that are constantly moving. If the house occupants stand still, this device can’t identify them.

But it’s still undergoing some advancements, so we can expect to see it get even better. 

FAQs #

What camera can see through walls? #

The sense-through-the-wall camera sees through walls. It is a recent technology by Camero, an Israeli company specializing in imaging.

Not only that, but this camera is powerful enough to detect a human in a building through their breathing!

Yes, even if they are more than 164 feet away from the camera.

Emergency responders and military officers can use this camera to know how far a person is from the wall, how many people are there, and what they are doing.

It was successfully deployed on a rescue mission by law enforcers in Mexico, where they managed to rescue the victim based on the data collected from this camera.

While it is simple, it may have to be placed against a wall, so the drone must get really close. But this could work against them since drones are quite detectable due to the propeller sounds.

 Can drones look in my window? #

Yes, drones can peer through your window, but even with a good zooming camera, they’d have to be close to your house.

You can detect a drone close to your house due to its blue or red navigation lights or the buzzing sound and report it to a local law enforcement authority.

Can drones see through curtains? #

Curtains greatly hinder the visibility of a normal camera sensor, so it will be difficult for a drone to see through a curtain.

What if it has a thermal camera? Still, curtains will block much of the energy these sensors detect, so not much will be visible.

If you have open windows, drones could see into your house, so consider adding some high-quality curtains.

Can a drone camera see at night? #

Most drone cameras see at night based on the ambient light available but may be limited because they cannot see beyond 165 feet.

Some high-end drones like the DJI Mavic 3 Thermal or Matrice T30 also have thermal cameras, allowing them to see at night even when there’s no ambient light.

Conclusion #

Can drones see through walls? Most of them can’t, except for industrial drones fitted with thermal cameras, Wi-Fi RSSI, and other penetrative systems.

Should you be worried? Yes, some worry is warranted, especially given the fact that a drone can be used to intercept your Wi-Fi system and spy on you through your devices.