Pattern-reconfigurable built-in antenna for data multiplexing with a single radio

Beam-space multiplexing has been demonstrated as a promising approach for transmitting multiple signals while using a single RF chain. This paper presents a novel beam-space antenna design that is very compact and integrated into a hypothetical portable platform. To provide required pattern reconfigurability, two silicon p-i-n diodes are used as the sole needed mounted elements, resulting in simpler reconfigurable loads and DC bias networks compared to previous works. A fully-operational antenna prototype is fabricated and measured, showing excellent agreement between simulations and measurements. The antenna can be used for single-radio multiplexing of two BPSK signals, enabling MIMO transmission in reduced-complexity hardware for future wireless applications.