On the design of wideband and tunable matching and decoupling networks for N-port antennas

This paper deals with the design of matching and decoupling network for a 4-port MIMO antenna system operating in the TV white spaces from 470 MHz to 790 MHz. After stating the limitations on the classical design based on hybrids, we consider a new approach in order to optimize the MIMO antenna performance, in terms of bandwidth, by taking advantage of some degrees of freedom in the matching and decoupling network. The maximum attainable bandwidth will be reported as a function of the network elements.