A Simple Wideband Magnetoelectric Dipole Antenna With a Defected Ground Structure

In this letter, a simple wideband magnetoelectric (ME) dipole antenna with a defected ground structure (DGS) is proposed and investigated. The dimensions of the pair of the quarter-wavelength patch antennas and the half-wavelength electric dipole antennas are changed to extend the impedance bandwidth. A DGS is used for impedance matching, which is novel in the ME dipole antenna design. A prototype of the proposed antenna is designed, fabricated, and measured. On combining impedance bandwidth and radiation pattern, measured results show that the proposed ME dipole antenna achieves an operating bandwidth of 86.9% (138-3.5 GHz) for vertical bar S-11 vertical bar < -10 dB, and a stable gain of 7.2 +/- 1.2 dBi is realized. A low cross-polarization level and low hacklobe radiation level are found across the operating bandwidth.