ADS-B is powerful but it is only one way to sense the sky, and it has blind spots. This is an honest map of the detection modalities that exist, what each is good and bad at, and precisely where AeroScope operates, so you know what it covers and what it does not.
| Modality | Strengths | Limitations |
|---|---|---|
| ADS-B (cooperative) | Identity, precise GPS position, global, free, real-time | Only sees aircraft that choose to broadcast; unauthenticated |
| Multilateration (MLAT) | Positions non-GPS Mode S targets from timing | Needs 4+ overlapping receivers; no identity for primary-only |
| Primary radar | Sees non-cooperative targets regardless of transponder | Expensive, no identity, limited low-altitude/small-target coverage |
| RF / Remote ID | Detects drone control/telemetry links and Remote ID | Range-limited; silent or non-Remote-ID drones evade it |
| Acoustic | Passive, cheap, can hear low/slow targets nearby | Very short range; weather- and noise-sensitive; no identity |
| Visual / EO-IR | Confirmation and classification by eye or camera | Line-of-sight, daylight/weather dependent, narrow field |
AeroScope is built on the ADS-B modality (with MLAT and Remote ID where networks provide them). That choice gives it global reach, real identity, and rich integrity metadata for spoof detection, at the cost of not seeing fully non-cooperative or silent targets. It is the right foundation for observer-relative awareness and the layer most amenable to open, reproducible analysis.
ADS-B is cooperative: it works only when the aircraft chooses to broadcast. Every technique below exists because that assumption fails in some situations, particularly for small uncrewed aircraft.
| Modality | Principle | Practical limits |
|---|---|---|
| Acoustic | Detects and classifies rotor or engine noise signatures | Very short range, typically hundreds of metres, and degrades badly with wind and urban noise |
| RF detection | Detects the control and video links between a drone and its operator | Defeated by autonomous flight with no active link, and regulated in many jurisdictions |
| Radar | Detects reflections regardless of cooperation | Small, slow, low targets are genuinely hard to separate from clutter and birds; costly |
| Optical and infrared | Camera detection and tracking | Needs line of sight and good conditions; limited range |
| Remote ID | Regulatory broadcast of drone identity and position | Cooperative again, so a non-compliant drone is invisible to it |
The consistent lesson is that no single modality is sufficient. Serious counter-UAS deployments layer several, precisely because each one's blind spot is another's strength. For what AeroScope can genuinely do with ADS-B and Remote ID, see drone detection.