摘要
数字基带转换器在VLBI系统中主要完成中频信号的基带转换和频段选择,文中采用频域抽取和邻信道合并技术设计一种VLBI数字基带转换器。采用该方法设计的转换器具有比较平坦的通带特性和较大的阻带衰减,能够方便地实现带宽的动态变化。文中对频域抽取进行理论推导论证,并根据邻信道合并的条件,详细说明了原型低通滤波器的设计方法,最后通过仿真验证了新方法的有效性。
The VLBI digital baseband converter realizes the baseband conversion of the intermediate frequency signal and the selection of frequency channels.A VLBI digital baseband converter is designed in this paper,which is based on the frequency domain decimation and adjacent channel merging.The new converter has the flat passband characteristic and large stopband attenuation characteristic,and can conveniently realize the dynamic change of bandwidth.The theory of frequency domain decimation is derived and the design of the prototype filter is elaborated.In the end,the validity of the new method is proved by the computer simulation.
出处
《遥测遥控》
2010年第1期5-10,16,共7页
Journal of Telemetry,Tracking and Command
