High Performance Single-Balanced Duplexer

A new topology for realizing a Single-input/Balanced-output duplexer with excellent rejection along with excellent phase and amplitude imbalance characteristics is presented. In addition to SE/BAL operation, this topology allows superior performances over conventional ladder topology. A Surface Acoustic Wave (SAW) duplexer for Band V CDMA covering the cellular frequency bands has been fabricated using this topology. The measurement results are presented and compared to single-single conventional duplexers. Finally, discussion is opened about the pro and cons of the method used.