Effect of Seasons on Millimeter Wave (35 GHz) Prevailing in Foliage Depth of Desert Region of India

Abstract

Performance of millimeter wave is of interest to communication scientists, researchers, industrialist as it shown communication window with wide spectrum and fewer losses. Wavelength above 10 GHz is subject to molecular absorption which limits its uses for many purposes. In this paper effect of changing seasons is presented on basis of experimental results. A trans-receiver system of 35 GHz is used to quantify the effect of increasing foliage depth (Trees in line) with changing seasons. Molecular absorption of water molecules can be clearly pointed out in observations. It is observed that least attenuation occurred in autumn while spring offers maximum attenuation to signal due to water molecules. Non linear attenuation with increase in foliage depth also indicates phenomenon of coherent scattering of millimeter wave. Coherent scattering re-combines the scattered components which are in-phase. Total 35.16% of signal in autumn seasons is said to be coherently scattered while least coherency of 18.63 % is observed in summers. In winter and spring coherency of signal is observed as 25.88% and 23.33% respectively. Observations and calculations presented in the paper may help scientist to develop an algorithm for communication system which can work proper with varying seasons