超声电机孤极在冲击环境中的传感特性测试

针对超声电机在冲击环境中的应用,提出了将旋转型超声电机中的孤极作为加速度传感器并进行了实验验证。基于圆环板的挠度微分方程与第2类压电方程得到孤极传感器电压灵敏度的理论表达式,并通过有限元方法得到传感器的谐振频率。搭建实验平台对传感器进行标定实验,结果表明,当冲击载荷的脉宽大于500μs时,孤极传感器与冲击过载保持良好的线性关系,但输出信号存在着较大干扰。为了在保持加速度信号特征的同时有效地去除干扰信号,设计了相应的数字滤波器,滤波后的信号仍然与加速度之间保持良好的线性关系。研究结果实现了超声电机的功能拓展,促进了超声电机在冲击环境中的应用。     

Generation of a frequency sextupled optical millimeter wave with a suppressed central carrier using one single-electrode modulator

We have theoretically and experimentally investigated the generation of optical millimeter wave (mm-wave) generation based on a quadrupling and sextupling technique using one single-electrode intensity modulator (IM) with a simultaneously suppressed optical central carrier. By adjusting the bias voltage and utilizing proper peak-to-peak voltage of the RF signal drive on the IM, undesired sidebands can be suppressed. Based on this rule, an experiment was performed to generate 48 and 72-GHz optical mm-waves using a sinusoidal clock source running at only 12 GHz.