Substrate integrated waveguide filter with high-design flexibility

Abstract

On the basis of TE₂₀₁/TE₁₀₁ mode substrate integrated waveguide (SIW) cavity resonators, an advanced methodology is proposed to design filter using nonresonating node with high-design flexibility. The bypass couplings are realized with the nonresonating TE₁₀ mode, so that arbitrarily positioned transmission zeros (TZs) can be obtained. To demonstrate the design flexibility, the approach is illustrated at example of a second-order filter providing Chebyshev, elliptic function type, and asymmetric characteristics. In addition, the modularity of the filter design is validated by the individual control of each TZ. A second-order 15 GHz SIW bandpass filter with 150 MHz bandwidth is then fabricated and measured. Comparison between the measurement values and simulation results verifies the effectiveness of the proposed configurations.

Acknowledgments

This work is supported by the Scientific Research Project of Sichuan Education Department (13ZB0078) and the Scientific Research Foundation of CUIT (KYTZ201212).