Space-time-state block coded mimo communication systems using reconfigurable antennas

Reconfigurable antennas offer a promising solution to the problem of space limitation in high-performance wireless communication over handset devices. In this paper, we propose a novel transmission scheme capable of extracting the maximum diversity gains of a Multiple-Input Multiple-Output (MIMO) communication system employing reconfigurable antennas at the transmitter, the receiver or at both ends of the wireless link, without the need for feedback. For a MIMO communication system using reconfigurable antennas at the transmitter, we propose a state-switching scheme in combination with an appropriate three-dimensional block code in order to extract the maximum possible level of diversity. When reconfigurable antennas are placed at the receiver end, we propose a state-selection scheme and prove that the proposed scheme is capable of achieving maximum diversity gains. Moreover, the state-selection method is able to obtain selection gain in addition to diversity gain. As shown, both state-switching and state-selection schemes can be combined together when reconfigurable antennas are used at both ends of the wireless link. Furthermore, we discuss and quantify the effects of switching delay on the performance of both state-switching and state-selection schemes. Finally, we provide simulation results to validate the performance of the proposed schemes. To demonstrate the gains of our schemes in realistic propagation conditions, we also conduct simulations using an actual reconfigurable antenna known as the PIXEL antenna.