A Novel Dual-Band Waveguide Filter With Multiple Transmission Zeros Based on TE102- and TE103-Modes

In this letter, the authors propose a novel dual-band waveguide filter with multiple transmission zeros (TZs) based on multi-coupled resonators in the rectangular waveguide using TE102- and TE103-modes. The dual-band of the filter is implemented by five oversized resonant cavities working in TE102- and TE103-modes with the central frequencies of the pass-bands close to 30.1 and 38.2 GHz, respectively. This rectangular waveguide filter consists of five resonators, each of which is connected to the source port through the narrow wall of the WR-28 rectangular waveguide, generating multiple TZs in the frequency range 26–40 GHz. To verify the performance of this novel filter, a prototype of it is fabricated and measured, achieving a good agreement between the simulated and measured results.