Study of a low insertion loss SAW filter with SPUDT structure using YZ-LiNbO3

To meet the demand for low insertion loss, we have studied a SAW filter with single phase unidirectional transducer (SPUDT) structure using piezoelectric materials YZ-LiNbO3. This article shows the simulation results of the SAW filter using Mat lab software with the SAW velocity 3488m/s and electromechanical coupling constant 0.048. The theoretical center frequency is 72MHz and the 3dB bandwidth is 2.9MHz. The total frequency response of the entire SAW device is the product of the frequency response of the input transducer and the output transducer. It can be seen from the simulation results that the magnitude response and the linear phase response of interdigital transducer are consistent with the theoretical values and the minimum insertion loss reaches 5.43dB. So the low insertion loss SAW filter with SPUDT structure using YZ-LiNbO3 adapts the requirements of the radar, communications and other electronic systems.