This study investigates the different optimal parameters of piezoelectric transducers polarized in the thickness direction. The studied parameters are regarding sensor and actuator embedding position in the thickness, sensor ratio and sensor dimensions. It involves a parametric study using MUL2 FE numerical tool, via coupled electro-mechanical two-dimensional models. The performance of the corresponding configuration was judged by the maximum output electric potential signal induced in the sensor due to the propagated Lamb Wave induced by the actuator. An experimental campaign was carried out on glass fiber/ polyester plates embedded with piezoelectric transducers to validate the different results.