Wideband Dielectric Resonator Antenna With a Tunnel

A wideband rectangular dielectric resonator (DR) with a horizontal tunnel is proposed. The bandwidth of the TE^y ₁₁₁ mode is increased by using the tunnel to reduce the Q-factor of the DR. As the tunnel height is increased, the electric field distribution of the TE^y ₁₁₂ mode is significantly modified such that its electric field distribution near the top surface of DR is similar to that of the TE^y ₁₁₁ mode, rendering a broadside radiation pattern. The band of the modified TE^y ₁₁₂ mode is merged with that of the TE^y ₁₁₁ mode to achieve a wide bandwidth of 20% (4.765.86 GHz) with broadside radiation pattern of vertical polarization on the xy-plane. The proposed DR antenna can be used in WLAN 802.11a applications.