用于VLBI数字基带转换的多相滤波技术研究  

The Study of DBBC Based on Poly-phase Filter Banks and FFT in VLBI

作　　者：陈岚[1,2,3] 张秀忠[1] 

机构地区：[1]中国科学院上海天文台,上海200030 [2]中国科学院研究生院,北京100039 [3]上海应用技术学院上海,上海200235

出　　处：《天文学进展》2008年第1期87-94,共8页Progress In Astronomy

基　　金：国家自然科学基金(10503009)

摘　　要：该文阐述了利用低通滤波器和多相滤波器技术实现VLBI数字基带转换的原理,建立了采用多相滤波器与FFT技术的数字基带转换系统的仿真模型;然后对本模型的算法复杂度进行了分析和比较;最后对该模型的正确性进行了仿真实验验证.With the further development on the Astronomy and deep space exploration, the incremental improvements that are expected on the VLBI is real-time, high sensitivity, reliability and more frequency coverage. VLBI data acquisition backend acts as an important role in VLBI station. Recently, based on the technique of A/D（Analog-to-Digital）, DSP（Digital Signal Processing）, FPGA（Field Programmable Gate Array） and so on, it is practical for middle-frequency signal to be sampled and digital processed directly. DBBC （Digital Base-band Converter） will take place of the analog BBC in VLBI data acquisition backend. In this paper, Full spectrum base-band converted signal model in VLBI has been established. The principle of digital base-band converters based on low-pass filter banks and poly-phase filter banks in VLBI are discussed in details. Mathematical models of these base-band converters are derived, arithmetic operations and complex are analyzed and compared. A simulation model of poly-phase filter banks is designed. All the experimental results show that the model is valid and practical.

关 键 词：天文观测设备与技术 VLBI 数字采集终端 数字基带转换器 低通滤波器 FFT 多相滤波器 

分 类 号：TN911.7[电子电信—通信与信息系统]