AREDN Network Planner

Radio horizon uses the same 4/3-Earth-radius model as the Line-of-Sight calculator (distance in miles = 1.415 × √height in feet). Node-to-node signal estimates use free-space path loss and a Friis link budget with both ends' TX power and antenna gain, assuming a clear, obstruction-free path — hills, trees, buildings, and Fresnel-zone obstructions will reduce real-world range and throughput below what's shown here. The "Likely link" / "Marginal signal" split (around -80 dBm) is a rough rule of thumb, not a guarantee of AREDN throughput or reliability. A link needs matching frequencies, mutual horizon range, and (for Sector/Dish ends) the antenna actually aimed at the peer. Directional antennas are drawn on the map as a wedge along their bearing at the horizon distance, not a precise antenna pattern.