COM parameter extraction from computer experiments with harmonic admittance of a periodic array of electrodes

A novel numerical method for determining the surface-acoustic wave (SAW) and the leaky surface-acoustic wave (LSAW) characteristics is proposed. The Green´s function method is used to simulate the excitation of waves in an electrically driven periodic array of electrodes. For the phase shift between consecutive periods close to π, the admittance may also be modeled within the coupling-of-modes (COM) formalism. We show that the dispersion relation and all COM parameters may be determined from the change in admittance as the phase shift is slightly varied, leading to significant savings in the computing time