Highly-efficient multiple antenna-systems for small MIMO devices

In this paper, we focus on highly-efficient multiple antenna-systems for small MIMO communicating devices. First, we perform a state-of-the art review of the best solutions developed by various researchers. Then we consider some fundamental aspects involved when integrating multiple antennas in a small terminal. Thereafter, we present several multiple antenna-systems designed at the LEAT of the University of Nice-Sophia Antipolis since 2004. We especially describe our neutralization technique dedicated to enhance the total efficiency of several radiators when they are closely placed over the same small ground plane. Last, we try to identify promising solutions and future trends.