A Low-Profile Filtering Circular Dielectric Patch Antenna for Cross-Band Decoupling

In this paper, a dielectric patch antenna with a low profile and a wide stop band is proposed for cross-band decoupling. Benefiting from the coupling of the circular dielectric patch resonator and ring dielectric resonator, two reflection zeros and one upper-edge radiation null is realized for the filtering performance. By introducing two non-metallic vias in the region where the dielectric patch harmonics are strong, wide stopband is obtained. Therefore, this filtering dielectric patch antenna can be used for reducing the mutual coupling between two elements operating different frequencies. The antenna element has a − 10dB impedance bandwidth of 7.2% at 3.5 GHz (3.36-3.61 GHz) and a profile height of 0.0427 free-space wavelengths with two radiating nulls. An antenna array was made on the basis of this unit, and the two units worked at 3.5GHz and respectively 4GHz, the isolation between ports is larger than 20dB.