Differential Dual-Polarized Dual-Band Filter Antenna with High Gain and Dual-Band Channel Separation

In this conference paper, a differential two-polarized dual-band filter antenna with the desired high gain and dual-band channel separation is proposed. Initially, the design based on two pairs of $\mathbf{C}$-shaped slot structures of different sizes expands the operating bandwidth of the antenna and improves the high-frequency out-of-band inhibition level due to the introduction of radiation nulls. Then, the introduction of radiation nulls between the high and low-frequency bands is achieved by the loading of shorting pins, which further improves the frequency selectivity between the upper and lower bands. Finally, the simulation results of the implement slot-loaded antenna indicate that the proposed antenna will perform bandpass filtering operation in the band range of $3.53 \mathrm{GHz}-4.03 \mathrm{GHz}$ and $5.3 \mathrm{GHz}-7.04 \mathrm{GHz}$ when different differential ports are excited, respectively. In addition, the antenna has a profile height of $0.069 \lambda_{0}$, while the peak gains of 10.4 dBi and 11.9 dBi are achieved at both low and upper frequencies, respectively.