Drone Detection FAQs

Most people aren’t engineers with years of experience studying and working with drones and drone detection technology. And that is perfectly okay because that’s what we’re here for. Since the inner workings of such technology can be somewhat nuanced, we compiled a list of drone detection FAQs we received over the years, with answers, to help you navigate the complexities. Some are general in nature and other are specific to the AeroDefense AirWarden™ system.

There's a form at the bottom of the page if you have a question not addressed here.

General Drone Detection FAQs

1. What are the differences between Radio Frequency (RF) and Radar drone detection?

Radio Frequency (RF) Detection Radar Detection
RF-based detection sensors can be passive or active. In the passive type, the sensor receives the signal and then detects the controller/drone based on the signal’s physical characteristics (if no demodulation involved) or based on the signal content (if demodulation is involved).

In the active type, after the sensor detects a controller/drone, it attempts to either jam the controller/drone signal or take control over the drone. Private entities are forbidden from using active sensors, and passive sensors that demodulate drone/controller signals violate federal surveillance laws.
The radar sends pulses of RF signals in different directions. If there is a drone in the area, the transmitted pulse is reflected from the drone back to the radar that detects the reflected signal.
Pros (for passive, non-demodulating sensors):
1. RF detection is the only method that can reliably detect both the drone and controller. This is important for the majority without the authority to interfere with a drone flight.

2. Does not require line of sight
1. Very long range
1. System must be configured to filter out ambient RF signals
1. Detects anything that moves (like birds for example) which leads to a high false positive rate in a busy environment

2. Requires line of sight

Drones and controllers can transmit their signal (data) over multiple frequency channels. In order to minimize interference and maintain security, some drones and controllers change their frequency channel of operation (i.e. frequency hopping) to transmit their signals.

3. How can a drone be traced back to the person piloting it?

Most drones and their controllers use a mutual communication system to transmit signals. Therefore, it’s usually safe to assume the controller location is also where the pilot is.

Drone Communications

4. What are the most effective anti-drone technologies?

There is no “silver bullet” when it comes to anti-drone technologies. The effectiveness of a system depends on the type of drone and use case. For example, RF detection technologies can detect drone controllers (pilots) while other technologies cannot, and these systems can operate effectively in urban areas.

On the other hand, radar struggles against small drones flying at low altitude but excels against large drones with high speed in open airspace.

Camera systems are limited by weather and line of sight but can recognize different types of drones and provide visual tracking on the target.

5. What are the key laws concerning drone detection technologies?

Last August, the Department of Justice (DOJ), Federal Aviation Administration (FAA), Department of Homeland Security (DHS), and Federal Communications Commission (FCC) issued an advisory guidance document to help non-federal public and private entities navigate the laws and regulations related to drone mitigation and detection technology. The advisory references various federal provisions and laws that could render many RF-based drone detection technologies illegal to use. The key laws mentioned in the detection capabilities section are The Pen/Trap Statute and The Wiretap Act which only apply to RF-based technologies. RF-based detection technologies that demodulate and decode drone and controller signals or read any signal content violate these laws.

6. Why can’t I just shoot down a drone?

The FAA considers drones as aircrafts. Therefore, FAA laws prohibit any interference with that flight.

In addition, if you shoot down a drone, you will likely be liable for any resulting damage to property or injury to innocent bystanders.

Feel free to check out our eBook on this subject!

7. Can commercial off-the-shelf drones be weaponized?

Since drones have payloads, nefarious actors can easily weaponize them to carry guns, explosives, and harmful chemical or biological materials.

8. Why do I need to worry about drones? I’m not a stadium or a refinery.

For safety, security, and privacy reasons. Drones can conduct surveillance and aid in cyber attacks. Furthermore, clueless and careless hobbyist pilots often lose control of their devices and sometimes cause property damage or injury.

9. Is a layered drone detection technology system truly needed to be effective?

This depends on your use case, budget, and acceptable risk tolerance. If your main objective is to detect a majority of off-the-shelf drones, then an RF-based system is highly effective. But be aware that some RF-based systems are dependent on a product library or only detect certain manufacturer’s drones (this is where your acceptable risk tolerance comes in). If you need to detect radio silent fully autonomous drones, then we suggest a combination of RF and radar.

10. Should I buy drone detection now or wait for legislation to change and buy a mitigation system?

Taking a drone out of the sky is extremely risky, especially over a crowd of people. That’s why only federal entities can take this action in very specific cases and finding the drone pilot is the safest form of mitigation. The ability to locate the drone pilot can actually prevent attacks when the drone pilot conducts test flights to gauge the security response.

There are drone detection systems available today that can provide drone and pilot location information and operate within federal regulations, so our suggestion would be to seek those out as it’s the safer option anyway.  

Given current tests to deliver transplant organs and transport people by drones, the FAA will likely be very hesitant to widely deploy devices capable of affecting drone flights.  

11. Are all RF detection systems the same?

No, some RF-based detection systems require authorization to operate if they jam/intercept or demodulate/decode the drone and/or controller signals. A sure sign of a system that requires authorization is its ability to identify a specific drone such as with its serial number.

RF detection systems that operate legally may differ in the effectiveness of their hardware, software, algorithms, and technology. This shows in their performance and ability to detect and locate drones and/or controllers simultaneously and in complex environments.

AeroDefense AirWarden™ Drone Detection FAQs

1. How long has AeroDefense been in business?

AeroDefense launched the business in 2015 and completed its first commercial deployment of the AirWarden system in 2017.

2. Is the system legal?

Yes. The AirWarden system can operate 24/7 without the need for prior legal authorization. The system passively monitors the local RF environment for drone and controller signals (RF spectrum sensing). It does not demodulate and decode drone signals.

As of Q1 2022, the AirWarden system is the first and only drone detection solution to receive the Department of Homeland Security (DHS) Support Anti-Terrorism by Fostering Effective Technologies (SAFETY) Act Developmental Testing and Evaluation Designation.

Although the AirWarden system's SAFETY Act designation does not confirm/deny system legality, it is significant that the description of our technology on the DHS SAFETY Act website states, “The Technology does not include a capability to defeat or interfere with the flight of Unmanned Aircraft Systems (UAS) or perform signal analysis functions which would require legal authorization.”

3. Your competitors claim they are also legal, so how is your system different?

Some vendors claim their system is legal because it doesn’t demodulate and decode signals and just reads the content on the outside of the signal (i.e. timestamp or GPS coordinates). However, as stated in the August 2020 Federal Advisory, this information requires a warrant to obtain according to federal surveillance laws.

Rather than analyze the drone/controller signal, the AirWarden system detects physical energy generated by frequency-hopping drones/controllers much like a Geiger-counter detects the presence of radioactive material. The underlying technology is considered spectrum sensing.

For WiFi drones, AirWarden’s spectrum sensing technology utilizes publicly broadcast WiFi information just like a cell phone sees WiFi networks or a GPS system uses WiFi for location accuracy.

4. What are some features or capabilities that are unique to AirWarden?

    • The AirWarden system detects multiple drones and pilots (controllers) simultaneously. Emerging technologies like spectrum sensing and machine learning make the AirWarden sensors highly resistant to RF noises and interference. This results in accurate detection and location information in the harshest RF environments such as Times Square/NYC where the AirWarden system tested successfully under government supervision as well as MetLife Stadium where it is commercially deployed. The system has a low false alarm rate in rural, desert, and urban areas.
    • Because the AirWarden system utilizes spectrum sensing and does not examine any signal content, it can operate 24/7 without prior legal authorization.
    • The AirWarden system does not rely on a product library like many other systems, so it can detect home-made “kit” drones and drones the system hasn’t seen before.
    • AeroDefense offers drone detection in-motion for patrol vehicles and other flexible deployment options. This includes the ability to store sensor electronics in a data center many kilometers away from the AirWarden detection antenna via fiber connection.
    • The AirWarden system is the first and, so far only, drone detection technology to receive a Department of Homeland Security SAFETY Act designation.

5. What is the range of the AirWarden system?

Detection range depends on a drone and controller’s ability to connect and fly in a specific operating environment (open field vs. urban setting with high RF noise). The AirWarden system detects RF-based drones at a distance from a sensor that highly correlates to a drones and controller’s two-way connection range. For example, if a drone can fly 1 mile from its controller in an open area, the system detects the drone when it comes within 1 mile of the sensor in the same type of area.

6. What are the procurement paths available? Can your system be purchased with Government Grants or through GSA?

AeroDefense is a recipient of a Small Business Innovation Research (SBIR) AFWERX/Air Force Research Laboratory (AFRL) Direct to Phase II grant, has met the competitive requirements, and can be purchased by any Federal Agency as sole source without the need for bid.

The AirWarden system can be purchased on the GSA contract through our partner, Brite, and through a number of other procurement paths including State/Local contracts.

Contact us to learn more.

7. Can your system integrate with our existing security and/or IT infrastructure? Will it interfere with navigational aids and/or communications?

AeroDefense engineers will work with your team to determine how to integrate with your existing security and/or IT infrastructure.

The AirWarden system will not interfere with navigational aids and/or communications because it is a passive system (i.e. receive-only).

8. What are the deployment and network communication options? Can your system be deployed wirelessly or via fiber optic?

AeroDefense provides flexible deployment options including fixed (permanent), temporary/portable, and vehicle and marine vessel-mounted for in-motion detection.

Fixed and vehicle/vessel-mounted deployments may utilize fiber connection which allows for storage of sensor electronics many kilometers from the detection antenna.

Sensor data communicated to the server will depend on the specific deployment's network design. Sensors can communicate over different types of mediums such as Fiber/ethernet, MESH, or Cellular/LTE.

9. Can your system be deployed across a meshed network city-wide or in multiple states or countries?

Yes, AeroDefense uses fiber, internet, or LTE network to accomplish this.

10. What alert options do you offer? Are there custom alerts available?

The AirWarden system provides color coded visual alerts in addition to audible cues when a detection event occurs via the AirWarden user interface. If desired, these cues can trigger only when a target is identified within a pre-determined area of interest to minimize unnecessary alerts.

SMS/MMS text and email alerts provide users detection and location information as well as "all clear" and sensor health status. The text and email alerts can be an integral part of alerting key stakeholders associated with the response plan and are configurable by user.

11. Does your system detect other RF signals outside of drones?

This depends on the use case, but in general, the answer is yes. The AirWarden system is tuned to detect the communication system/signals that behave like a drone or a controller. In some cases the system/signal may not belong to a drone. For example, during a government supervised test in NYC, the AirWarden system detected NYPD’s robotic dog controlled by a remote controller.

The AirWarden system can also detect any unusual RF activity that presents within the monitored area. These signals can be authorized during the calibration process if they are known to be non-threatening.

NYPD Robotic Dog – Drone Detection FAQs
NYPD Robotic Dog Detected by AirWarden System

12. What industries does AeroDefense work with?

Current AirWarden system users are in the sports, corrections, and military industries. However, AeroDefense can support many use cases in other industries such as critical infrastructure, public safety, and airports.

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Published by Hadi Kasasbeh, RF Research Engineer June 15, 2021
Hadi Kasasbeh, RF Research Engineer