【摘要】 针对DVB-T接收机的中频数据进行数字下变频(DDC)处理。分析了引入噪声的原因,同时提出解决方案。为了便于ASIC实现,在设计模块时除了考虑功能实现还尽可能做到结构简化。在设计数控振荡器(NCO)时采用了CORDIC算法,在设计抽取滤波器时采用多相结构的半带滤波器级联,通过MATLAB仿真证明该系统能有效消除镜频干扰及噪声影响,恢复出符合系统要求的数据。更多还原

【Abstract】 Bring out a method to process IF signals of DVB-T receiver by using DDC technique. Analyze the reason of noise and give the solution to reduce its affection. Meanwhile in order to integrate DDC as ASIC, the paper not only focuses on realizing performance but on optimizing structure as well. In this paper we choose CORDIC to realize NCO, choose multi-phase half band filter to realize decimation filter. The performance of its ability to reduce mirror frequency interferes and noise effect is validated by using MATLAB simulation.更多还原