Tropospheric effects on microwave propagation in hilly terrains

The authors deal with the propagation characteristics observed over a long hop line-of-sight microwave link. An attempt is made for the first time in India to study systematically the fading observed over this long hop, hilly terrain, microwave links' and also to suggest some remedial measures. Correlation studies made with the help of radiosonde data and sodar observations indicate that the observed fading is mostly due to the super-refractive conditions prevailing in the 200 to 300 m region above the surface leading to multipath fading. The upward tilting of antennas in the convective environment for improvement of the system performance has been suggested.<
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