Frequency conversion through nonlinear mixing in acoustic waves
Frequency conversion through nonlinear mixing in acoustic waves
复制标题
声波非线性混频频率变换
DOI：
10.1063/5.0018074
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发表时间：
2020-08
影响因子：
3.2
通讯作者：
J. Schneider;Ting Lu;Sidhant Tiwari;Xiating Zou;A. Mal;R. Candler;Y. Wang;G. Carman
中科院分区：
文献类型：
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作者：
J. Schneider;Ting Lu;Sidhant Tiwari;Xiating Zou;A. Mal;R. Candler;Y. Wang;G. Carman
变频是现代通信设备中必不可少的工具。传统上，频率转换是通过非线性电感器或电容器的参数耦合来实现的，其电抗由载波调制。在本研究中，探索了非线性声学兰姆波器件用于同时进行信号滤波和频率转换。三组叉指式换能器制作在压电氮化铝（AlN）薄膜上，以提供载波、低功率信号波，并接收频率转换的混合波。制造并测试了两个器件，以利用 AlN 的机械非线性来演示上变频和下变频，并将结果与非线性电路模型进行比较。非线性电路模型用于将实验观察到的现象与声学材料的固有非线性联系起来。当载波功率为28 dBm时，AlN的非线性度达到最大值2.8%。分析模型用于预测设备性能以及物理尺寸。这些分析结果表明，非线性声学混频器和滤波器可以达到亚毫米尺寸，这比使用非线性电感器和电容器的传统结构小几个数量级。
Frequency conversion is an essential tool in modern communication devices. Traditionally, frequency conversion is achieved through parametric coupling via nonlinear inductors or capacitors whose reactance is modulated by a carrier wave. In this study, nonlinear acoustic Lamb wave devices are explored for simultaneous signal filtering and frequency conversion. Three sets of interdigitated transducers are fabricated on a piezoelectric aluminum nitride (AlN) thin film to provide a carrier wave, a low-power signal wave, and to receive a frequency converted mixed wave. Two devices are fabricated and tested to demonstrate frequency upconversion and downconversion by utilizing mechanical nonlinearity of AlN, and the results are compared to a nonlinear circuit model. The nonlinear circuit model is used to link experimentally observed phenomenon to the acoustic material's intrinsic nonlinearity. The nonlinearity of AlN reaches a maximum of 2.8% with a carrier wave power at 28 dBm. An analytical model is used to predict device performance along with physical dimensions. These analytical results show that nonlinear acoustic mixers and filters can approach sub-millimeter sizes, which is orders-of-magnitude smaller than conventional structures using nonlinear inductors and capacitors.