By AeroDefense on December 13, 2023

Drone Detection/Counter-UAS Terms and Definitions

Welcome to our quick guide on drone detection terminologies and definitions—a roadmap to navigate the evolving landscape of aerial security.

As drones become increasingly ubiquitous, understanding the terminology surrounding their detection is crucial for ensuring safety, privacy, and security.

From radar systems to acoustic sensors, this guide aims to demystify the jargon, providing clarity on the technologies and methodologies used to detect and mitigate potential drone threats in various environments.

Whether you're a security professional, a technologist, or someone intrigued by the fascinating world of drone detection, this compilation of terms will serve as an invaluable resource in deciphering this complex field.

124n System The Preventing Emerging Threats Act of 2018 provides DOJ and DHS with tailored legal waivers for DOJ, DHS, DOE and DOD (codified by US Code 6 Section 124n)  to mitigate credible drone threats to designated facilities and assets which would otherwise be prohibited by various federal laws. The Act was extended from original expiration of 9/30/2023 until 2/03/2024. Systems that require such authorization are considered 124n systems.
Acoustic Sensor A sensor which is composed of a microphone and a processor to sense physical sound waves and determine if the sounds match sound patterns attributed to drones.
Camera Electro-Optical (EO) A sensor which is composed of electronics to receive electromagnetic waves in the visible light spectrum. The light may be measured and evaluated if it matches patterns attributed to drones.
Camera Infra-Red (IR) A sensor which is composed of electronics to receive electromagnetic waves in the infrared light spectrum. The light may be measured and evaluated if it matches patterns attributed to drones.
Counter-UAS The term “counter-UAS” refers to the capability to lawfully and safely disable, disrupt, or seize control of an unmanned aircraft (UA) or unmanned aircraft system (UAS). 
Demodulation Demodulation is the process of extracting information contained within a modulated carrier wave. Radio Frequency (RF) based drone detection systems that detect and track UAS by monitoring the communications passed between a UAS and its ground control station may implicate the Pen/Trap Statute and Wiretap Act.
Drone Detection The general term which speaks to a technology or solution(s) that offer capabilities to detect, track, and/or identify a drone.
FAA Remote ID broadcast The Federal Aviation Administration (FAA) Remote Identification (Remote ID) rule provides for identifying drones in flight and the location of their control stations, reducing the risk of them interfering with other aircraft or posing a risk to people and property on the ground. The rule provides crucial information to security, law enforcement, and other agencies charged with ensuring public safety. The rule applies to all drones that require FAA registration. The information required to be broadcast includes but is not limited to drone I.D. (serial number), drone location and altitude, pilot location, speed, and time mark. FAA enforcement for pre-existing drones to 12/16/2022 was extended from 9/16/2023 until 3/16/2024. Remote ID utilizes ASTM’s F3411-19 standard.
Fixed Sensor A drone detection sensor that is permanently installed at a location.
Frequency Hopping Spread Spectrum (FHSS) A method of transmitting radio signals by rapidly changing the carrier frequency among many frequencies occupying a large spectral band. The changes are controlled by a code known to both transmitter and receiver. Many UAVs adopt frequency hopping spread spectrum (FHSS) technology to efficiently and securely communicate with their radio controllers (RCs) where the signal follows a hopping pattern to prevent harmful interference.
Library based If a system relies on a product library, it must be manually updated when new drones hit the market and may not detect kit, custom drones used by nefarious actors.
Mobile Sensor  A drone detection sensor that can be moved from one location to another.  The sensor might operate while stationary, in-motion, or both. 
Omni-directional Commonly referring to transmitting signals in, or receiving signals from, any and all directions. (e.g., an omnidirectional antenna that disperses equal radio power in all directions).
Radar Radar systems work by emitting short pulses of signal. Objects in the radar signal path reflect back to the radar antenna where they are measured to identify the nature of the object
Radio Frequency (RF)  An RF sensor works by passively listening to the Radio Frequency spectrums in which drones communicate with their controller. The most common bands of communication are the 2.4 GHz and the 5.8 GHz bands.
RF Direction Finding Radio receiver and antenna systems for determining the direction of the source of a radio signal.
Sensor Network A network of sensors which work together to detect, track, and/or identify drones. The sensors may be the same or different types. 
small Unmanned Aerial System (sUAS) The Department of Defense often refers to commercial type drones as sUAS to differentiate between larger drone types.
Spectrum Sensing Spectrum sensing is a technique for monitoring the local electromagnetic spectrum. This can be used by RF sensors to monitor the environment for changes and determine if the spectrum is being utilized by signals associated with drones.
Unmanned Aerial System (UAS) Also known as a drone, refers to a combination of components such as an unmanned aircraft, a ground-based controller, and a system of communication between the two. These systems can be remotely piloted or autonomous, and they often carry sensors, cameras, or other payloads for various purposes like surveillance, data collection, photography, or even delivery.
Unmanned Aerial Vehicle (UAV) A specific type of aircraft that operates without a human pilot onboard. Often referred to as a drone, UAVs can be remotely controlled by a human operator or fly autonomously based on pre-programmed flight plans or dynamic automation systems.


Published by AeroDefense December 13, 2023