Characterization of SAW filters based on GaPO4

The results of research into Surface Acoustic Wave - SAW - filters have been recognized for their efficiency and versatility in the electrical signals processing (1,3). Gallium Orthophosphate (GaPO4) is a relative new material, which has a long term high stability and, moreover, has an excellent behavior with temperature variation (2,3). The characterization of SAW filters based on GaPO4 is uses the comparative analysis of simulated results of parameters, with different software programs, which were developed for designing of these filters. Simulation covers the determination and analysis of the characteristics of this filter, namely, mechanical parameters (constructive) and operational parameters in comparison with the design data. In order to obtain the parameters of SAW filters we have used the algorithms and software for modelling, simulation. The paper presents several versions of software programs, in Matlab and Microsoft Visual C#, for the design of GaPO4 SAW filters and their interpretation. These modeling, simulations were performed successively by each program, until we set the parameters of SAW filter. By the comparison of the data obtained with each program, we have improved the constructive dimensions of fingers, we obtained the desired parameters. With this data, we realised SAW filters based on GaPO4, and with the help of the Network Analyzer we measured parameters of the filter, which are presented in the paper(2,10).