Hybrid SIW‐GCPW Filtering Crossover Using Embedded Resonators for Order‐Enhancement

ABSTRACT

This letter presents novel substrate‐integrated waveguide (SIW) filtering crossovers. A third‐order filtering crossover is realized by employing four cambered SIW cavities and one circular cavity. To further increase the order, four grounded coplanar waveguide (GCPW) resonators are introduced between the cambered and circular cavities, thereby realizing a fifth‐order filtering crossover. This method demonstrates its capability to achieve a wider 3‐dB fractional bandwidth (3‐dB FBW) while maintaining the same circuit area. Moreover, by exploring the use of half‐mode SIW (HMSIW) cambered cavities, the feasibility of a more compact circuit area is also demonstrated.