Reduced Overhead Training for Multi Reconfigurable Antennas with Beam-Tilting Capability. - Hamid Eslami; Chitaranjan P. Sukumar; Daniel Rodrigo López; S. Mopidevi; Ahmed M. Eltawil; Lluis Jofre; Bedri A. Cetiner (IEEE Trans. Wirel. Commun., 2010)