Fast determination of coupling-of-modes parameters based on strip admittance approach

Abstract

This paper proposes a simple technique to determine parameters required in the coupling-of-modes (COM) analysis for surface acoustic wave (SAW) devices. It is based on finding zeros and poles in the strip admittance Y(β,ω) for fixed β=2π/pI where β is the wavenumber and ω is the radial frequency. This corresponding to the input admittance of infinite interdigital transducer (IDT). This technique is directly applicable to the analysis of IDTs with multiple fingers. Effectiveness of this technique is highlighted when IDTs under consideration possess directivity.