Abstract
The use of dual orthogonal polarizations to optimally conserve frequency spectrum in microwave link, otherwise known as cross polarization, has received considerable interest in the recent time in the field of electromagnetic wave propagation in sand and dust storms. Cross polarization in dust storms occurs due to the non-sphericity of the falling dust particles and the tendency of the particles to align in a direction at a time i.e. canting angle. The realization of a dual-polarized system is however limited by degree of cross polarization discrimination (XPD) that can be achieved between the two orthogonal channels. Therefore, theoretical investigation has been carried out in this work to estimate the cross polarization at microwave and millimeter wave bands by non-spherical dust particles in dust storms. The XPD being the parameter for characterization of cross polarization, is predicted using propagation constants’ differentials and canting angles, as inputs. Apart from both differential phase rotation and attenuation, it has been found that the cross polarization produced by ellipsoidal dust particles strongly depend on the particle canting. XPD decreases with an increase in canting angle. It has also been observed that the values of differential attenuation increase with increasing frequency for visibility and thus depends directly on frequency. Lastly, the obtained results show that cross polarization is significant during severe visibility and for dry dust storm; the XPD is good and acceptable for dual polarization systems.