RF Detection Range Calculator
Calculates the maximum distance at which a passive RF sensor can detect a drone's transmitter. Based on the Friis transmission equation with drone EIRP and receiver sensitivity as inputs.
Drone Transmitter
Typical consumer: 0.01–0.2 W · FPV: 0.025–1 W
RF Sensor (Receiver)
Max Detection Range
4.44 km
Drone EIRP
20.0 dBm
Free-space model. Real-world range depends on antenna orientation, terrain, and background RF noise. Obstructions can reduce range by 50–80%.
Detection Range vs Receiver Sensitivity
| Sensitivity | Detection Range |
|---|---|
| -75 dBm | 790 m |
| -80 dBm | 1.41 km |
| -85 dBm | 2.50 km |
| -90 dBm | 4.44 km |
| -95 dBm | 7.90 km |
| -100 dBm | 14.05 km |
| -110 dBm | 44.43 km |
Formula (Friis transmission)
R = (λ / 4π) × √(Pt × Gt × Gr / P_min)
λ = c/f · Gt = drone TX gain (linear) · Gr = receiver antenna gain (linear) · P_min = receiver sensitivity in watts.