The main purpose of the design of ultrasonic vibration turning system is to increase the vibration amplitudc of cutting tip. The increase of cutter nose amplitude is due to the horn of the vibration system. It has bee...The main purpose of the design of ultrasonic vibration turning system is to increase the vibration amplitudc of cutting tip. The increase of cutter nose amplitude is due to the horn of the vibration system. It has been found out that not only the amplification bar possesses the function of amplitude amplification (this is called one-stage amplitude amplification in展开更多
文摘提出了一种适用于射频—微机电系统(RF-MEMS)滤波器的高性能接口放大电路。利用微纳工艺制备了相对带宽为1.4%、中心频率为73.02 MHz的硅基MEMS滤波器,针对其高阻抗、高插入损耗特性,设计了基于运算放大器的低噪声、高增益的两级放大电路和阻抗匹配电路。仿真结果表明:接口电路对高频的MEMS滤波器微弱电流信号具有良好的放大效果,增益可达62.75d B,噪声系数为3.35d B,S22反射系数为-46.91 d B,使RF-MEMS滤波器的插入损耗降低至0.56 d B。测试与PCB板级电路级联的MEMS滤波器输出信号表明:RF-MEMS滤波器的插入损耗降至16.2d B,相对带宽为1.4%,中心频率为73.02 MHz,提升了MEMS滤波器在无线通信中的应用潜力。
基金Project supported by the National Natural Science Foundation of China
文摘The main purpose of the design of ultrasonic vibration turning system is to increase the vibration amplitudc of cutting tip. The increase of cutter nose amplitude is due to the horn of the vibration system. It has been found out that not only the amplification bar possesses the function of amplitude amplification (this is called one-stage amplitude amplification in
