TRANSMISSION-LINE MODEL FOR IMMERSED QUARTZ-CRYSTAL SENSORS

The impedance concept in propagation problems and in transmission line s is used to model an acoustic wave propagating in a quartz-crystal se nsor loaded by a liquid medium. An impedance evaluation of the immerse d quartz sensor is presented and different aspects are developed. Theo retical curves drawn from this model are compared with experimental va lues measured with a network analyser, motional elements of the equiva lent circuit are derived for the quartz crystal with a liquid loading, different characteristic frequencies are calculated and the correspon ding frequency shifts due to liquid contact are compared with the Kana zawa result.