Application of X-parameters in studying nonlinearities in BAW and SAW filters

Nonlinearity can give rise to intermodulation distortion and harmonics in Bulk Acoustic Wave (BAW)/ Surface Acoustic Wave (SAW) devices operating at high input power levels. To understand such undesired effects, behavioral model based on the Poly-Harmonic Distortion (PHD) principle can be used as a possible modeling approach to accurately predict the nonlinear behavior of BAW/SAW filters and duplexers. In order to investigate the origin of non linear response of BAW/SAW devices, it is necessary to study some properties of the materials used within the devices. In this work, the nonlinear Mason models of BAW/SAW filters [1–3] are created and compared with the X-parameters measurement. In the next step, role of materials in the generation of nonlinearities in BAW/SAW devices are discussed based on [4, 5, 16]. The X-parameter measurements based modeling of SAW/BAW components up to third order harmonics and intermodulation products have been carried out with a nonlinear vector network analyzer (NVNA).