Multiport Reactive Loading Matching Technique for Wide Band Antenna Applications Using the Theory of Characteristic Modes

A systematic framework is presented for designing an antenna with arbitrary shape and expanding its input impedance and pattern bandwidths using reactive loading. This method, unlike other design procedures, allows us to control the current distribution over the antenna structure with potentially fine granularity. This technique is applied to wire and microstrip antennas and it is shown to achieve a very good impedance and radiation pattern performance over the desired band. The loads are combination of Foster and non-Foster elements, which are generally required to obtain such dramatically improved performance.