Cross-correlation and total efficiencies of two closely spaced sleeve dipole antennas

This paper shows that for the special case of 3D uniform field incidence, with a cross-polarisation ratio (XPR) near unity, the cross-correlation coefficient and total efficiency are the measures for predicting diversity performance and can be estimated from measured 5-parameters. The results for the cross-correlation coefficients and efficiencies, as a function of dipole separation distance, are compared for two parallel side-by-side sleeve dipole antennas using three different methods: 3D anechoic chamber measurements, CST microwave studio numerical simulations, and S-parameter measurements. It is shown that the total efficiency is a critical diversity performance measure since the cross-correlation coefficients are very low due to pattern deformations and large efficiency degradations occur due to antenna coupling