Magnetoelectric Dipole Filtering Antenna Based on CSRR With Third Harmonic Suppression

In this letter, a high selectivity filtering magnetoelectric (ME) dipole antenna with harmonic suppression is investigated. By etching a complementary split resonant ring (CSRR) on shorted wall of ME dipole, a radiation null at upper passband edge can be obtained. The intrinsic radiation null at lower passband edge of ME dipole is utilized, together with the radiation null generated by CSRR, to obtain high selectivity. In addition, to suppress the third harmonic of the antenna, a stepped impedance resonator is loaded on the Г-shaped feeding structure. For verifying, a prototype operating from 1.44–2.79 GHz is designed, fabricated, and measured. Compared with the traditional ME dipole antenna, the proposed filtering antenna shows upper and lower stopband rejection levels as high as 16.61 and 17.84 dB, respectively. Furthermore, a third harmonic suppression level of 12.78 dB is obtained. Good agreement can be observed between the simulation and measurement.