Seasonal propagation effects in an obstructed rural radio path at 462 MHz

The author reports on a 12 month observation of signal strength in a 462 MHz radio link operating over a 2.4 km, irregular rural path containing a deciduous tree grove 150 m in diameter. The received signal level was biphasic, with temporal changes of 1.8 and 6.7 dB/month at the beginning and end of foliation, respectively. There was a maximum shift of 8 dB from summer to winter and up to 2 dB variation from wet to dry conditions