一种多模式高效全频谱基带转换系统设计

Design of an Efficient Multi-mode Full Spectrum Digital Baseband Converter

数字基带转换器是VLBI(Very Long Baseline Interferometry)系统中的重要部分。为了进一步加强国际合作和国内中科院VLBI网的联测能力,我国深空站需要支持Mark5B和RDEF两种数据输出格式。参照美国深空网DSN和上海天文台数字基带转换器的技术指标,设计一种同时支持实信号输出和复信号输出的多模式全频谱基带转换系统,同时支持Mark5B和RDEF两种数据格式。该系统采用基于多相滤波器组高效均匀信道化和正交混频相结合的基带转换方法,能够实现可分析频带内无盲区无失真全频谱基带转换功能。

The digital baseband converter is an important part of VLBI（ Very Long Baseline Interferometry）system. In order to strengthen the international cooperation and the ability of joint observation with Chinese Academy of Sciences VLBI network, our deep space station needs to support both MarkSB and RDEF data formats. Referring to the technical indexes of digital baseband converters of Deep Space Network and Shanghai Astronomical Observatory, a multi-mode full spectrum digital baseband converter which supports both real signal and complex signal output is designed, and the corresponding data formats are MarkSB and RDEF. The method which combines the PFB（ Poly-phase Filter Bank） efficient uniform channelization with the orthogonal mixing is used in the digital baseband converter, which can realize the full spectrum baseband conversion of analyzing bandwidth without blindzone or distortion.