A Rectangular Waveguide Slot Antenna with Dual-band Rejection

A dual-band rejection rectangular waveguide transmission line is introduced, where two stopbands are achieved by T-type and II-type resonators loading at the bottom wall of the rectangular waveguide. The frequencies and bandwidths of the two stopbands can be tuned by adjusting parameters of resonators. To verify this concept, a rectangular waveguide filtering four-slot antenna with two stopbands is designed and simulated. Compared with a traditional rectangular waveguide four-slot antenna, the simulated results show that the proposed filtering antenna operates well in 5.6-5.9 GHz and realizes suppression levels stronger than 39.9 dB and 51.9 dB in 6.6-7.1 GHz and 8.4-9.3 GHz, respectively.