一种多路分时复用抗混叠滤波器设计与实现  

Design and implementation of a multi-channel time division multiplexing anti-aliasing filter

作　　者：朱洪翔[1] 董青[1] 张迪[1] ZHU Hong xiang;DONG Qing;ZHANG Di(Chinese Flight Test Establishment,Shaanxi Xi’an 710089,China)

机构地区：[1]中国飞行试验研究院测试所,陕西西安710089

出　　处：《电子设计工程》2020年第8期160-164,169,共6页Electronic Design Engineering

摘　　要：一种多路分时复用抗混叠滤波器针对应用于飞行试验的网络化机载采集系统中数字信号混叠问题,采用变采样率的抗混叠滤波器的设计,解决在数字信号处理过程中由于采样率过高,在进行整数倍抽取时有可能会出现数字信号混叠问题。同时将数字滤波器通过FPGA实现,实现了多路分时复用功能,支持8路同步采样数据的数字信号处理,并进行滤波器特性测试,对于8 kHz的原始信号,半带滤波器的截止频率为Fs/4,即2 kHz,经过系统后的-3 dB对应的信号频率2 048 Hz,幅频特性曲线与Matlab仿真结果一致。A multi-channel time division multiplexing anti-aliasing filter is designed for the aliasing of digital signals in a networked airborne acquisition system applied to flight tests,and adopts an anti-aliasing filter with variable sampling rate. In the digital signal processing process,due to the high sampling rate,digital signal aliasing may occur during integer multiple extraction,which solves the problem that digital signal aliasing may occur when performing integer multiple extraction in the digital signal processing process due to the high sampling rate. Digital filter is realized by FPGA,which realizes multi-channel time division multiplexing function and supports digital signal processing of 8 channels of synchronous sampling data.The filter characteristic test is performed on the system. For the original signal of 8 kHz,the cutoff frequency of the half-band filter is Fs/4,that is,2 kHz,the signal frequency corresponding to-3 dB after the system is 2 048 Hz. The amplitude-frequency characteristic curve of the system is consistent with the Matlab simulation results.

关 键 词：分时复用 抗混叠 数字滤波器 FPGA 补偿滤波器 巴特沃兹滤波器 

分 类 号：TP274.2[自动化与计算机技术—检测技术与自动化装置] TN79[自动化与计算机技术—控制科学与工程]