| Passive RF Detection | Radio-frequency control, telemetry, and video-link emissions | Approximately 1–10 km, depending on transmitter power, antenna height, terrain, and interference | 80–95% for emitting drones Lower when the aircraft is autonomous, shielded, or radio-silent | Often available Can receive compatible broadcast Remote ID information when the drone transmits it | 0.5–3 seconds | Wide-area coverage; passive operation; can help identify control links and operator direction | Reduced effectiveness against autonomous flight, frequency-hopping links, encrypted or proprietary signals, and non-emitting aircraft | Perimeter monitoring, critical infrastructure, airports, and temporary security zones |
| Active Radar Detection | Reflected radio waves from the aircraft and its moving parts | Approximately 0.5–5 km for small drones; range varies significantly with radar frequency, target size, clutter, and weather | 70–95% Higher in controlled environments with suitable clutter filtering | Not directly available Radar detects physical movement rather than Remote ID broadcasts | 1–5 seconds | Works against radio-silent and autonomous drones; provides bearing, range, altitude, and track data | Birds, vegetation, buildings, ground clutter, and weather may create false alarms; performance depends on radar placement and configuration | Large sites, border areas, industrial facilities, and open outdoor environments |
| Electro-Optical / Infrared | Visible-light and thermal imaging cameras | Approximately 0.2–2 km, depending on optics, lighting, contrast, weather, and target size | 50–85% Usually strongest after cueing by another sensor | Not directly available | 2–10 seconds Longer when manual confirmation is required | Visual confirmation; useful for evidence, classification, tracking, and incident assessment | Night, fog, rain, glare, foliage, occlusion, and small or distant targets can reduce performance | Security verification, evidence collection, and daylight or well-lit sites |
| Acoustic Detection | Propeller and motor sound captured by a microphone array | Approximately 0.1–0.5 km in quiet conditions; shorter in urban or industrial noise | 40–75% Highly dependent on background noise, wind, and drone type | Not available | 2–8 seconds | Passive, low-power, and useful where radio emissions are absent or difficult to analyze | Limited range; affected by traffic, machinery, wind, rain, reflections, and other aircraft or wildlife sounds | Quiet campuses, restricted indoor areas, and short-range supplementary detection |
| Remote ID Receiver | Standardized broadcast data received over compatible short-range wireless links | Commonly up to several hundred meters; actual range depends on transmission power, receiver height, obstacles, and local rules | High for compliant broadcasts within coverage It does not detect non-broadcasting or non-compliant aircraft by itself | Core function May provide aircraft identification, location, velocity, and take-off or operator-related data where legally transmitted | 1–5 seconds | Low-cost identification; supports compliance monitoring and rapid correlation with known flights | Not a complete counter-drone sensor; coverage is local and information depends on legal transmission and protocol compatibility | Airspace compliance, event management, airports, and integration with broader detection systems |
| RF + Radar Fusion | Passive RF detection combined with radar tracks | Approximately 1–8 km, subject to the shorter effective range of the deployed sensors | 88–97% in suitable field conditions | Available when compatible broadcasts are received | 1–4 seconds | Combines identification of emitting drones with detection of radio-silent targets; improves track continuity | Requires careful time and location synchronization; RF and radar coverage may not overlap evenly | Critical infrastructure, airports, ports, energy facilities, and large perimeters |
| Radar + EO/IR Fusion | Radar cueing with visible and thermal camera confirmation | Approximately 0.5–5 km, depending on radar range and camera optics | 85–97% in clear or moderately challenging conditions | Not inherently available Can be added through a separate Remote ID receiver | 2–8 seconds | Radar provides early warning while cameras support visual classification and operator verification | Camera performance decreases in darkness, fog, rain, glare, and heavy obstruction; response may involve human review | Security operations centers, prisons, stadiums, and high-value facilities |
| RF + Radar + EO/IR + Remote ID Fusion | Multisensor combination with software-based track correlation | Approximately 1–10 km for early warning, with identification range determined by the individual sensors | 92–99% under well-calibrated, site-specific conditions Actual results depend on terrain, clutter, weather, traffic, and target behavior | Available for compatible compliant aircraft Physical sensors remain necessary for non-compliant or radio-silent targets | 1–5 seconds for automated alerting Human confirmation may take longer | Best overall coverage; combines detection, classification, identification, and evidence collection while reducing single-sensor blind spots | Highest cost and integration complexity; requires calibration, cybersecurity controls, data governance, and trained operators | National borders, airports, major events, military or government sites, and high-consequence infrastructure |