Radio through a maize field

A tasselling maize crop can swallow a LoRa signal. Gateway height matters more than gateway count.

Wet, dense leaves absorb radio waves. Field measurements in the tropics show around 56 dB of extra loss through canopy, with signals falling to −110 to −115 dBm, the edge of what a LoRa receiver can hear.

The loss changes with the crop. Seedlings barely matter; at tasselling, when leaf area peaks, the link is at its weakest. We plan every network for that worst week, with gateways mounted well above the tallest crop and high-gain antennas.