Experimental determination of COM model parameters for SAW transversely coupled resonator filter

An analysis model for surface acoustic wave (SAW) transversely coupled resonator filters has been developed by use of the coupling-of-mode theory. To make the model work properly, an approach based on a transversely coupled six-port test structure has been designed which, in conjunction with a computer-aided multiport data manipulation and fitting program, enables the experimental determination of all necessary parameters. The experimental approach and the associated theoretical background are described. Key features of the computer-aided data fitting program are summarized. A comparison between theory and experimentally measured results shows excellent agreement over an 80-dB range