Article ID: 22.20250657
Substrate integrated waveguide (SIW) provides an attractive solution to the integration of planar and nonplanar circuits by using a planar circuit fabrication process. However, it is difficult to achieve a small size and broadband on the basis of a single-layer SIW. Herein, we propose a compact substrate integrated waveguide filter with E-shaped slot line resonators (ESRs) etched on the top of SIW cavities, which achieves broadband and miniaturized bandpass. Moreover, out-of-band rejection has been improved. The SIW filter with a chip size of 7.6𝑚𝑚 × 3.6𝑚𝑚 × 0.4𝑚𝑚 has the center frequency of 24GHz and respective passband width of 3GHz fabricated by micro-electro-mechanical systems (MEMS) technology. Measured results of this filter exhibit a high selectivity and a maximum in-band insertion loss of approximately 1.8 dB.
