In this paper, we propose a new block coding scheme to increase the diversity gain of multiple-input–multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems over slow-fading wireless channels. We assume that the antenna elements at the transmitter are reconfigurable and capable of independently changing the physical characteristics of their radiation patterns. The composite right-left handed leaky-wave antenna is an example of reconfigurable antennas with such characteristics. We use this feature of the antennas and develop a block coding scheme that exploits, in addition to the spatial and frequency diversity, a new additional degree of diversity, which is called state diversity. We determine the maximum achievable diversity order of the proposed coding scheme in spatially correlated frequency-selective channels. To demonstrate the performance of the proposed block coding technique, we provide numerical results and compare them with those of the previously developed coding schemes for MIMO-OFDM systems. The results indicate that the proposed code achieves significantly higher diversity and coding gain, even in spatially correlated channels, compared with the existing counterparts.
['Vida Vakilian', 'Jean-François Frigon', 'Sébastien Roy']
On Increasing the Slow-Fading Channel Diversity Using Block-Coded MIMO-OFDM With Reconfigurable Antennas