Dual-Band Acoustic Wave Filter Synthesis Based on the Conventional Standalone Ladder Topology

In recent works, the acoustic wave ladder topology has positioned as a strong candidate to implement dual-band filtering solutions. This work aims to describe the synthesis considerations related to this topology, commonly used for single-band devices, as well as describe the particular constraints arising from it. Dealing with the synthesis of a dual-band filter as a fully in-line ladder structure requires careful attention in the arrangement of resonators, issue that is covered in this paper. An L1-L2 GPS synthesized filter is used as a vehicle for exemplification.