A reconfigurable dual-mode Filter in Embedded Suspended Stripline Substrate Technology (ESSS)

A new configuration of embedded suspended stripline in PCB is proposed where a direct copper-to-copper connection joins the metalized cavity walls with the ground layer. The proposed stack-up has the advantage of an increased shielding compared to stack-ups based on via walls. A dual-mode filter demonstrator is designed and realized with discrete frequency tunability. The designed filter frequency is set around 30.5 GHz where the insertion loss (IL) is 1.06 dB and the Fractional Bandwidth (FBW) is 10.3%. The resonant frequency can be tuned to 29.60 GHz using a hardwired switch for a proof of concept. The realized prototype measurements show a good agreement between simulated and measured filters response.