Multi-Mode Wideband Filtering Antenna for 5G Millimeter-Wave Communication

The interconnection loss between the radio frequency (RF) front-end and the antenna become prominent for system integration in the millimeter-wave (mm-wave) band, and joint design is required at the device level. Because of the higher propagation loss in the mm-wave band, the cost for communication coverage will increase sharply. This is the main impetus for the development of filtering antenna with low cost and low interconnection loss. In this paper, through the aperture sharing and mode hybridization, three adjacent modes are sequentially excited to achieve broadband characteristics. The simulation impedance bandwidth of the antenna is 24.1~28.4 GHz with a relative bandwidth of 16.4% and the peak realized gain is 5.7dBi. Radiation null can be realized at the edge of the passband with an increased coupling path between the slot and U-shaped ring, hence producing a more than 20dB out-of-band suppression.