Output Signal Correlation of Dual Polarized Base

The use of diversity in the reception of mobile radio signals is well known and is implemented in most wireless systems of today. Several authors have studied polarization diversity [1{4]. However, no study has to our knowledge analyzed the e ect of the actual base station antenna characteristics on the diversity performance. In this paper we study the envelope correlation and signal strength at the outputs of a 45 to vertical dual polarized antenna in di erent radio environments. The 45 con guration is often used in mobile communications since it allows for identical azimuthal radiation patterns and equal mean received power for the two channels. We assume that the radio channel consists of uncorrelated Rayleigh signals in the vertical and horizontal polarizations. Two di erent antenna types are studied, a dual polarized aperture coupled patch antenna, ACP, and a slanted dipole con guration.