Impact of Antenna Correlation in Electrically Dual-polarized Small Antennas

In spatially correlated channels, the diversity provided by dual-polarized (DP) antenna systems is known to provide an increase in spectra efficiency compared to traditional co-polarized (CP) systems. However, as the antenna dimensions decrease relative to the wavelength, antenna correlations will increase due to the electrically-small antenna elements. In this work, we model the impact of electrically small antennas through mode coupling and characterize performance degradations in wide-band Rayleigh fading channel models, where performance is measured in terms of bit error rates and packet error rates. System performance is measured using a multiple-input, multiple-output (MIMO) emulation testbed. Signal-to-noise ratio (SNR) penalties due to antenna correlations are found to exceed 10 dB when coupling factors are significant.