Compact filtering crossover design based on SIW quintuple‐mode resonators

Abstract

A compact filtering crossover utilizing substrate integrated waveguide (SIW) quintuple-mode resonator (QMR) technology is proposed for the first time. Benefiting from this technology, the proposed crossover firstly breaks the status quo that SIW crossover filtering response is only concentrated in single passband, thereby extending the applications of the SIW crossovers. In design, the QMR is derived by embedding metal-via holes in the conventional SIW resonant cavity, thus to produce quintuple resonant modes featuring with specific electric distributions. Next, by dividing these modes into two groups, a triple-mode bandpass filter (BPF) channel and a single-mode dualband BPF channel are both realized. To implement two flat passband channels, there are two SIW cavities cascaded. And also, the isolation between two channels is implemented by employing the orthogonal characteristic. In this way, a crossover is implemented. The proposed design method can be a good candidate for developing SIW multi-band filtering crossovers. For verification, an example circuit has been designed, fabricated, and measured.

A dual‐band filtering crossover with large frequency ratio for microwave and millimeter‐wave applications

“…A dual-band filtering crossover based on microstrip resonators was implemented in Chin and Pang. 18 However, all these structures, [10][11][12][13][14][15][16][17][18] no matter with or without filtering characteristics, can only provide a frequency ratio smaller than 5. This is insufficient for the emerging 5G applications, which require to support microwave and millimeter-wave bands simultaneously.…”

“…In Gao et al, 16 a patch crossover with dual‐band filtering property was proposed for the first time. In Qu et al, 17 a planar dual‐band filtering crossover based on SIW quintuple‐mode resonators was proposed. A dual‐band filtering crossover based on microstrip resonators was implemented in Chin and Pang 18 .…”