Study of excitation on beam ports versus element ports in performance evaluation of diversity and MIMO Arrays

The main concern of the current communication is to elicit the influences of beam-forming upon different multiple-input multiple-output (MIMO) parameters in a rich scattering environment. A detailed study of desired parameters is presented with particular stress on total radiation efficiencies observed on element ports and beam ports. Measurements are performed in a reverberation chamber (RC). The results illustrate that performance as viewed through element and beam ports are, in general, equal. Hence, they confirm that in a rich and isotropic scattering environment, beam-forming technique does not prove beneficial. They also demonstrate that as long as received radiation power is preserved, the shapes of the elements´ patterns are irrelevant.