Sunrise and sunset effects as observed on microwave propagation over a line-of-sight path

Microwave signal propagation provides an effective measure of studying the variable nature of the atmosphere. Sunrise and sunset periods are characterized by the dissolution and formation of nighttime temperature inversions. Signal amplitude recordings at 6.7 GHz over DumDum-Andul line-of-sight (LOS) communication link during post-sunrise period are characterized by the appearance of an enhancement in signal strength (as high as 20 dB). The sunset effect or the evening transition is observed as an enhancement in signal amplitude of about 10- 12 dB over the link. The signal characteristics observed during transition periods over the 6.7 GHz DumDum-Andul link are studied herein.