Capacity enhancement of MIMO systems using electrically-small, biomimetic antenna arrays

We study the performance of a MIMO communications system that uses electrically-small biomimetic antenna arrays (BMAAs). We show that MIMO systems using BMAAs can outperform those that use conventional antenna arrays with the same aperture sizes. This is shown to be due to the efficient extraction of the maximum available power from all linearly-independent modes of excitation of the array, which results in the natural decoupling of the elements. As a proof of concept demonstration, we examine the use of a two-element BMAA consisting of two λ/4 monopole antennas as part of a MIMO communication system. The capacity that can be achieved from a MIMO system using this antenna is compared with the capacity obtained if the MIMO system uses a conventional antenna array with the same aperture dimensions. This is done through computer simulations by designing prototypes of both antennas and using them in an emulated MIMO communications systems. These results demonstrate that using the BMAA in the MIMO system results in considerable capacity enhancement.