Influence of loss on the critical frequencies of ceramic resonators

Piezoresonators are often characterised by equivalent circuits. Loss then usually appears as an ad hoc addition to the circuit. Future stability and manufacturing reproducibility requirements dictate a more detailed understanding of the types of loss mechanisms and their disposition in equivalent networks. The effects of a lossy piezoelectric coupling coefficient, k*, on the complex resonance frequencies of a plate resonator driven in a simple thickness mode are explored