Multi-functional antennas using polarization-rotation artificial magnetic conductor structures

Abstract

A novel polarization rotation technique based on an artificial magnetic conductor (AMC) structure is proposed. A new polarization-rotation AMC (PRAMC) with a height of only 0.04 λ0 is designed and a large polarization rotation bandwidth of 29.1% can be achieved. Firstly, the PRAMC is applied to design a low-profile circularly polarized dipole antenna with a broad axial ratio bandwidth and beamwidth. In addition, combining a PRAMC-based multi-polarized dipole antenna with a switch network, a novel polarization-reconfigurable antenna is achieved, in which three polarization states of right-handed, left-handed circular polarization (RHCP, LHCP) and +45° linear polarization (LP) can be realized by controlling the dc bias of the switches accordingly. Moreover, a new active corner-cut PRAMC loading with several varactors is proposed to achieve a novel frequency- and polarization-reconfigurable dipole antenna for applications in multi-function wireless communication systems.