| Summary: | 碩士 === 義守大學 === 電機工程學系 === 89 === A surface acoustic wave (SAW) oscillator consists of a high quality factor SAW resonator and an active circuit. A SAW resonator composes of Interdigital Transducers (IDT) and reflectors fabricated on a piezoelectric substrate. The properties of substrate, the modes of wave propagation, the geometry of IDT and reflecting grating determine the characteristics of a SAW resonator. In this thesis, the Mason’s equivalent circuit was applied to model the IDT. The Coupling of Modes (COM) was used for reflector. The cascade model and the theory of multiport connection were applied to simulate the frequency response. The ST-X quartz was chosen as the substrate for the reason of stable temperature coefficient in the room temperature. One-port SAW resonators were discussed in detail. First of all, self-developed program was used to simulate the frequency response and input impedance of the resonator. The simulating’s results were then put in the RF CAD design tool to design an oscillator. Finally, the performance of resonators and oscillators were compared with experimentation.
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