Low-Cost Printed Circuit Board W-Band Dual-Mode SIW Bandpass Filters Technology

In this chapter, critical challenges associated with W-band filters in modern millimeter-wave communication and radar systems were addressed. Dual-mode filters can make full use of the degenerate modes of the cavity to achieve better selectivity characteristics. Capacitive and inductive boundary conditions also have different characteristics. When the boundary condition at the coupling gap is set to an appropriate impedance, dual-mode excitation can be achieved. From the perspective of field distribution, the dynamic effect of the electric field is rotational around the center over time, which indicates the superposition of two different field distributions.