A new concept in SPUDT design: the RSPUDT (resonant SPUDT)
A new concept in SPUDT design: the RSPUDT (resonant SPUDT)
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SPUDT 设计的新概念：RSPUDT（谐振 SPUDT）
DOI：
10.1109/ultsym.1994.401542
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
F. Roux
中科院分区：
文献类型：
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作者：
P. Ventura;M. Solal;P. Dufilié;J. Hode;F. Roux
提出了 SPUDT 设计的新概念，从而产生了一种称为谐振 SPUDT (RSPUDT) 的新型低损耗换能器结构。在换能器内部创建谐振声腔，同时保持低损耗所需的全局单向性。结果，换能器的一些区域是局部向后方向的。利用 RSPUDT 的 SAW 滤波器表现出改进的滤波器特性（例如通带纹波、形状因子）并导致滤波器更加紧凑。开发了两种 RSPUDT 基本单元。第一个是将经典 EWC 单元推广到 RSPUDT 概念，而第二个在相同的临界尺寸下将每个波长的反射率提高 50%。对 38° Y 旋转石英上的 200 MHz 和 110 MHz 低损耗滤波器进行的测量表明了人们对这些新型 SPUDT 结构的兴趣。 200 MHz 滤波器具有 0.30 MHz 的 2 dB 带宽和 1.01 MHz 的 40 dB 带宽，而 110 h MHz 滤波器则结合了 912.25 MHz 的 40 dB 带宽和 0.9 MHz 的 0.5 dB 带宽。
Presents new concepts in SPUDT design, leading to a new low loss transducer structure called Resonant SPUDT (RSPUDT). Resonant acoustic cavities are created inside the transducer while keeping a global unidirectionality required for low loss. As a result, some areas of the transducer are locally backward directional. SAW filters utilizing the RSPUDT exhibit improved filter characteristics (e.g. passband ripple, shape factor) and result in more compact filters. Two kinds of RSPUDT elementary cells were developed. The first one is the generalization of classical EWC cells to RSPUDT concept while the second improves the reflectivity per wavelength by 50% with the same critical dimensions. Measurements on both 200 MHz and 110 MHz lowloss filters on 38° Y rotated quartz are presented to illustrate the interest in these new SPUDT structures. The 200 MHz filter exhibits a 2 dB bandwidth of 0.30 MHz and a 40 dB bandwidth of 1.01 MHz while the 110 h MHz filter combines a 40 dB bandwidth 912.25 MHz and a 0.5 dB bandwidth of 0.9 MHz