A Wideband Magneto-Electric Dipole Antenna with Electromagnetic Bandgap Structure

A millimeter wave (mm-wave) magneto-electric (ME) dipole antenna is proposed for wideband applications. The ME dipoles are fed by a U shape microstrip feedline through aperture slots on the metal planes. The metal planes are modified by adding several elliptical shaped slots to achieve a wide bandwidth. This antenna exhibits a simulated fractional impedance bandwidth of BW=45.8%(25.1-40GHz). A conventional electromagnetic bandgap (EBG) structure is designed to suppress the surface propagation modes. The EBG structure allows a reduction of the simulated side lobe level (SLL). At the frequency f2=39GHz, the simulated SLL with and without EBG structure are SLLw=-15.4∼dB and SLLw/o =-6.6 dB, respectively. The simulated fractional 3 dB gain bandwidth is BWg=42.4%(26-40GHz) and the highest simulated realized gain is RGmax=8.20∼dB at the frequency fm=34 GHz, while the simulated radiation efficiency is η> 0.91 over the 3 dB gain bandwidth.