AirWarden Legality

AirWarden Legality

The number one question people ask about Radio Frequency (RF) drone detection is if it is legal. What about the legality of the AirWarden™ spectrum sensing Drone and Pilot Detection, Location and Alert System?

While AeroDefense cannot give legal advice and we are not attorneys, we have prioritized operation within US drone detection regulations.

Here is what we know about the laws and how our products operate with regard to each statute. We provide links to the Department of Justice (DOJ) source sites so you or your attorneys can make your own judgement.

Department of Justice Statutes

  • DOJ Prohibits Interception of Radio Communications
    • Section 605(a) of Title 47 prohibits persons who transmit or receive wire or radio communications from divulging such communications except to authorized persons.”
  • How does DOJ define “Interception”?
    • DOJ defines interception as acquisition of the contents of electronic communications.
    • “The term “intercept” is defined in 18 U.S.C. § 2510(4) to mean the aural or other acquisition of the contents of any wire, electronic, or oral communication through the use of any electronic, mechanical, or other device.”
  • So what defines “Contents”?
    • DOJ defines the word “contents” in 18 U.S.C. § 2510(8) to include “any information concerning the substance, purport, or meaning of any wire, oral, or electronic communication.”
    • “It is significant that this definition intentionally does not include the identity of the parties or the existence of the communication.”
      • “The definition distinguishes between the substance, purport, or meaning of the communication, and the existence of the communication or transactional records about it.”
      • For example, for surveillance cameras to show images of a person having a conversation with another person, operators do not require a warrant. Obtaining the content of the conversation requires a warrant.
    • “Content” means any information inside the signal. For example, the dialing, routing, addressing, or payload information utilized in the processing and transmitting cannot be captured without legal court authorization per 18 US Code Chapter 206 §3121. This regulation generally prohibits pen register and trap and trace device uses.
      • In the drone detection environment, it is possible that extraction of as little as a time-stamp from the signal may qualify as “content.” 

The analogy in Figure 1 may help explain how different types of RF-based drone detection systems operate.

Drone Detection System Legality Example
Figure 1
  • Systems that “read the letter” absolutely require authorization. For example, these drone detection systems provide information such as the drone’s serial number as well as its GPS coordinates.
  • Other systems claim to be legal without authorization because they only “read the address on the envelope”, but they actually do require authorization. These systems might read the time stamp on the drone signal.
  • Then there are systems like AeroDefense’s that don’t read any information and just “observe if envelopes exist or not” and do not require authorization. Put another way, AeroDefense’s RF-based system, AirWarden, is not looking for the content inside or outside of the envelope, just whether there is an envelope at all, as depicted in Figure 1. Our systems monitors for the presence of RF signals in the environment.

AirWarden does not intercept any signal.

AirWarden Spectrum Sensing Legality

How It Works

More than 90% of drones operate in the ISM RF band using proprietary protocols. The drone controller communicates UPWARD to the drone while the drone telemetry and/or video signals are communicated DOWNWARD to the controller via 2.4/5.8 GHz or 400/900 MHz (less common) frequency bands. There are two types of drones: 

  • Frequency Hopping Spread Spectrum (FHSS)
  • WiFi or Bluetooth

Rather than analyze the drone/controller signal, AeroDefense’s AirWarden™, 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 utilizes publicly broadcast WiFi information just like a cell phone sees WiFi networks or a GPS system uses WiFi for location accuracy. It is not illegal to intercept communications “made through an electronic communication system that is configured so that such electronic communication is readily accessible to the general public.”

DOJ Statutes Answered

  • Section 605(a) of Title 47 & 18 U.S.C. § 2510(4) – As mentioned previously, AirWarden does not intercept any signal. It only uses high probability spectral and pattern signal processing algorithms to detect physical drone signal characteristics and identify drone frequency hopping patterns. 
  • 18 U.S.C. § 2510(8) – DOJ’s definition of “content” does not include the existence of the communication, but it does include any information inside the signal. AirWarden does not decode or demodulate the signal to extract the drone type, signal time stamp, GPS coordinates, or the “Return to Launch” GPS coordinates. It only looks for the existence and pattern of the RF signal. 


By our interpretation of the statutes, AeroDefense does not intercept the content of any wireless communications as defined by 18 U.S.C. § 2510(4), 18 U.S.C. § 2510(8), Section 605(a) of Title 47, respectively.

Mitigation regulations are not cited because AirWarden only detects and locates the drone and pilot (controller).