一种应用于DDS+PLL混合频率综合器中的滤波器设计  

A Filter Design Applied in DDS+Pll Hybrid Frequency Synthesizers

作　　者：程少庭 雷雪梅[1] 柴晓荣 CHENG Shao-ting;LEI Xue-mei;CHAI Xiao-rong(College of Electronic Information Engineering, Inner Mongolia University ,Hohhot 010021 ,China)

机构地区：[1]内蒙古大学电子信息工程学院,呼和浩特010021

出　　处：《内蒙古大学学报（自然科学版）》2018年第4期407-415,共9页Journal of Inner Mongolia University：Natural Science Edition

基　　金：国家自然科学基金(61640011);内蒙古自然科学基金资助项目(2016MS0617)

摘　　要：主要研究设计了PLL+DDS环外混频混合频率综合器中的带通滤波器,系统把DDS与PLL经混频器混频后,通过窄带带通滤波器滤波,得到了所需中心频率的输出信号.为了缩短设计周期,提高微带线带通滤波器的性能,通过ADS中的无源电路设计向导,设计出了一种中心频率为2.5GHz,带宽为65MHz,阻带频率在2.375GHz和2.625GHz处衰减幅度大于50dB的平行耦合微带线带通滤波器.最后经过实物测试表明,设计出的平行耦合微带线带通滤波器满足各项指标要求.A bandpass filter used in hybrid frequency synthesizer structure of PLL＋DDS mixing in the outside of the feedback loop is designed.The output signals of DDS and PLL are mixed by a mixer,filtered by a narrowband bandpass filter.Then the output signal of the required center frequency is obtained.In order to shorten the design cycle and improve the performance of microstrip bandpass filter,the design wizard in the passive circuit of ADS is used.And the parallel coupled microstrip bandpass filter with a central frequency of 2.5 GHz and a bandwidth of 65 MHz is designed.The attenuation of the stopband frequency at 2.375 and 2.625 GHz is more than 50 dB.Finally,physical tests show that the designed parallel coupled microstrip bandpass filter meets the requirements of various indexes.

关 键 词：PLL DDS 微带线带通滤波器 混频器 

分 类 号：TN713.5[电子电信—电路与系统]