With the widespread application of drones in civilian and other fields, "low-altitude, slow-speed, small-sized" (LSS) targets have become a major threat to security systems. Anti-drone technology has thus emerged as a crucial means to safeguard national, public, and critical infrastructure security.

     This article systematically analyzes the current development status, technical principles, and future directions of selected anti-drone technologies.

 Definition of Anti-drone Technology 

    Anti-drone technology, also known as drone countermeasure systems or C-UAS (Counter-Unmanned Aircraft Systems), refers to legal and safe systems or devices that detect, identify, jam, deceive, and control drones. Modern anti-drone systems typically adopt a multi-layered defense architecture, integrating functional modules such as detection, identification, tracking, and countermeasures. These systems provide 360-degree all-round protection in various weather conditions, with a detection range of over 2 kilometers. 

Radar Detection Technology

     The core principle of radar is based on the transmission and reflection of electromagnetic waves. The system emits electromagnetic waves of a specific frequency; when the beam encounters a target, it reflects. By receiving and analyzing these reflected signals, key information such as the target’s distance, azimuth, altitude, and speed can be accurately obtained, providing precise guidance for subsequent interception.

     Anti-drone technology achieves drone monitoring, identification, and neutralization through radar detection, radio jamming, electro-optical identification, and other means, effectively curbing the misuse and illegal activities of drones.

     Modern anti-drone radar systems mainly include pulse Doppler radar, continuous wave radar, and frequency-modulated continuous wave (FMCW) radar. 

High-Resolution Radar for Drone Detection

     High-resolution radar is optimized specifically for drone detection, capable of identifying commercial drones with small radar cross-sections (RCS). Since the RCS of commercial drones is similar to that of birds, advanced radar systems use machine learning (ML) and artificial intelligence (AI) technologies to distinguish drones from other flying objects.

 Phased Array System (Azimuth Mechanical Scanning + Elevation Phased Scanning)

     The azimuth mechanical scanning + elevation phased scanning radar is a high-performance, reliable 3D radar detection device primarily used for detecting and locating low-altitude aircraft targets. It adopts a phased array system, achieving target detection and tracking through azimuth mechanical scanning and elevation phased scanning, and can provide real-time, accurate target track information (including spatial position, speed, etc.). Widely used in prisons, airports, bases, and other locations, it provides strong technical support for security work.

Key features of this radar include:

    • Multi-dimensional precise detection: Enables accurate detection of low-altitude/ultra-low-altitude targets in terms of distance, azimuth, altitude, and speed.

    • High positioning accuracy: Offers high detection capability, adaptability, and low false alarm rates for ultra-low-altitude, slow-speed, small targets. 

    • All-weather operation: Supports 24/7 unattended operation while avoiding electromagnetic radiation interference to operators. 

    • Long detection range: Depending on the product, it can detect and track long-distance targets.

    • Strong adaptability: Lightweight and miniaturized design allows temporary erection or fixed deployment based on mission requirements, with quick and easy installation. 

Anti-Drone System Modules 

 Soft Kill Technology

    Soft kill technology interferes with drone systems through non-physical means, while hard kill technology directly destroys targets via physical methods.

    •  Jamming Technology:Radio frequency (RF) jamming is the most widely used countermeasure. By emitting jamming signals in the same frequency band as drone communications, it blocks the communication link between the drone and the operator. Modern jamming devices typically use dynamic frequency jamming and wideband jamming to counter drone frequency hopping technology.  

    •  Deception System:By emitting false navigation signals, it interferes with the drone’s navigation system, causing it to misjudge its position or fail to navigate correctly. This technology can force drones to deviate from their predetermined routes or land in designated areas.  

 Hard Kill Technology 

    In addition to soft kill technologies, hard kill methods such as laser weapon systems, kinetic interception technology, high-power microwave (HPM) weapon technology, and hard physical interception technology are used to intercept or destroy "black fly" drones (illegally flying drones). 

 Challenges and Future Directions 

    Anti-drone systems face multiple challenges in future development, including the rise of AI, upgrading drone technology, and legal/regulatory restrictions.

    Looking ahead, anti-drone systems are expected to:

     1. Develop towards intelligence and automation: Integrate advanced algorithms and AI to quickly and accurately respond to complex situations. 

     2. Move towards multi-function integration: Combine different countermeasures to flexibly address various drone threats. 

     3. Strive for portability and concealment: Facilitate quick deployment and rapid activation when needed.  Anti-drone technology will continue to evolve to meet the growing demands of security, providing more robust protection for national and public safety.