RF-MEMS滤波器的高性能接口电路设计  

Design of high-performance interface circuit for RF-MEMS filter

作　　者：代雪梅 陈泽基 阚枭 袁泉[1,2] 张晓青 杨晋玲[1,2] DAI Xuemei;CHEN Zeji;KAN Xiao;YUAN Quan;ZHANG Xiaoqing;YANG Jinling(Semiconductor Research Institute,Chinese Academy of Sciences,Beijing 100083,China;University of Chinese Academy of Sciences,Beijing 100049,China;Beijing University of Information Technology,Beijing 100192,China)

机构地区：[1]中国科学院半导体研究所,北京100083 [2]中国科学院大学,北京100049 [3]北京信息科技大学,北京100192

出　　处：《传感器与微系统》2021年第2期79-82,共4页Transducer and Microsystem Technologies

基　　金：国家自然科学基金重点资助项目(61734007);国家自然科学基金面上资助项目(61874116);北京信息科技大学2018年度实培计划项目(71B1910806)。

摘　　要：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。A high-performance interface amplifying circuit for radio frequency micro-electro-mechanical system( RF-MEMS) filter is presented. A silicon-based MEMS filter with relative bandwidth of 1. 4 % and center frequency of 73. 02 MHz is fabricated by micro/nano fabrication process. As for high resistance and high insertion loss( IL) characteristics that,MEMS filter has low-noise,high-gain two-stage amplifier circuit based on operational amplifier and impedance matching circuit are designed. The simulation results indicate that the interface circuit has good amplification effect on HF filter with the gain can achieve 62. 75 d B,noise coefficient of 3. 35 d B and S22 reflection coefficient of-46. 91 d B,which can make the insertion loss( IL) RF-MEMS filter decrease to 0. 56 d B.Testing output signal of MEMS filter cascaded with the PCB board relative circuit indicates that the IL of the RFMEMS filter is reduced to 16. 2 d B,the relative bandwidth is 1. 4 %,and the center frequency is 73. 02 MHz,improving the application potential of MEMS filters in wireless communications.

关 键 词：射频—微机电系统(RF-MEMS)滤波器 两级放大电路 阻抗匹配电路 低噪声 高增益 低插损 

分 类 号：TH89[机械工程—仪器科学与技术] TP212[机械工程—精密仪器及机械]