A Novel Pattern-Reconfigurable Cylindrical Dielectric Resonator Antenna With Enhanced Gain

A cylindrical dielectric resonator antenna with switchable beams is proposed in this letter. The high-order HEM 21(1 + δ) mode of cylindrical dielectric resonator is excited at 5.8 GHz for high gain and quasi-endfire radiation pattern for the first time. Eight switches, whose locations are carefully optimized, are used to control the beam directions. By turning on one of the eight PIN diodes, the proposed antenna can rotate the beam to the opposite direction of the switch. For each direction, the antenna exhibits high gain (7.27 dBi), high efficiency (86.1%), low cross-polarization level, and similar radiation patterns. With these advantages, the antenna can be widely applied in wireless communication systems, especially for multiple-input-multiple-output (MIMO) systems.