ZHANG Yanhua1 XU Fangqian1 WANG Wen2
(1 Zhejiang University of Media and Communication Zhejiang 310018)
(2 Institute of Acoustics, Chinese Academy of Sciences Beijing 100190)
Receive Dec. 3, 2010
Revised Jan. 23, 2011
Abstract This paper presents an optimal design on surface acoustic wave reflective delay line using coupling of modes(COM) model. The reflection coefficient S11 of the SAW device is deduced to evaluate the device performance. Typical SAW reflective delay line consists of a piezoelectric substrate, and interdigital transducer (IDT) and several reflectors positioned along he acoustic propagation direction. The influence of the design parameters of the device, such as structure of the IDT, reflector types, etc. on device performance are investigated, and the optimal design parameters are determined. Based on these parameters, a 434MHz SAW reflective delay line with single phase unidirectional transducers and three shorted grating reflectors is fabricated on 41°YX LiNbO3. The measured S11 agrees well with the simulated one. Sharp reflection peaks, high signal noise ratio(S/N), and low spurious noise between the reflection peaks are observed.
PACS numbers: 43.35, 43.38, 43.58
