高性能数字电视调谐器本振的设计与实现

Design and Implementation for High Performance Digital TV Tuner Local Oscillator

在讨论数字电视调谐器本振相位噪声和分析直接数字频率合成器(DDS)原理及特点的基础上,提出了一种DDS与锁相环(PLL)混合电路用于调谐器本振的方法,可使其在所用频率点上无相位截断噪声,从而使调谐器本振的相位噪声大大改善,最后通过实验证明了这种方法的有效性.

This paper discusse the phase noise of digital TV tuner local oscillator. Based on the analysis of DDS theory and feature, presents a method to design tuner local oscillator using direct digital synthesizer (DDS) and hybrid phase locked loop(PLL)circuit. According to this method all the DDS output frequency we wanted have no phase truncation noise, and the phase noise of tuner local oscillator have more improved. This method has been proved in an experiment.