Broadband Magnetoelectric Dipole Filtering Antenna for 5G Application

Abstract

A magnetoelectric (ME) dipole filtering antenna with high out-of-band suppression level and high selectivity is proposed in this letter. The intrinsic radiation null of the traditional ME dipole antenna is used, which produces a good filtering response at the edge of the lower passsband. A pair of vertical parasitic metal planes are introduced between the shorted walls and fed through slot coupling, which can be equivalent to an additional magnetic dipole. The radiated electric field of the magnetic dipole is opposite to that of the original antenna at higher frequency, forming a wide stopband radiation null, which greatly improves the high-frequency stopband suppression level of the antenna. Furthermore, a pair of T-shaped coupling stubs are inserted between the shorted wall and electric dipole, producing another radiation null with high roll-off rate at higher frequency. The measurement results show that the −10 dB impedance bandwidth of the proposed antenna is 49.4% (3.2–5.3 GHz). Its low-frequency stopband suppression level is greater than 16.6 dB and high-frequency stopband suppression level is greater than 26.0 dB. Moreover, the antenna radiation pattern is stable and symmetrical in the whole operating passband, and the filtering response is desirable.