A Triple-mode Wideband Bandpass Filter Using Single Rectangular Waveguide Cavity

作者:Feng, Shi-Fen; Wong, Sai-Wai*; Zhu, Lei; Chu, Qing-Xin
来源:IEEE Microwave and Wireless Components Letters, 2017, 27(2): 117-119.
DOI:10.1109/LMWC.2016.2647003

摘要

A triple-mode wideband bandpass filter (BPF) is proposed. It consists of a single rectangular waveguide cavity with two small metal rods to be inserted into the cavity from input/output feeding ports. As such, one TM110 mode, one TM210 mode, and one TM130 mode can be simultaneously excited in this cavity to form up a wide frequency passband. The fractional bandwidth is 58% at center frequency of 5.5 GHz with low insertion loss (< 0.5 dB). Furthermore, this design approach is good for miniaturization compared with traditional single-mode filter. For validation, a proposed filter is fabricated using silverplated aluminum metal cavity. Both theoretical and measured results are presented with good agreement.