A study of polarisation diversity for a microcellular environment

In this paper an analysis is carried out on the propagation mechanisms which cause polarisation changes of the electromagnetic field in a simplified microcellular environment. For this purpose a street surrounded by buildings is studied adopting a four-ray model and using the Fresnel equations for the reflections of the electrical field. The gain which can be achieved when exploiting polarisation diversity is determined with respect to a system receiving only the vertically polarised field. The linear combining techniques used to process the signal received on the two orthogonally polarised antennas were switching, equal gain combining, and maximal ratio combining. For a 10 per cent outage probability the average gain observed was 8 dB