文档介绍：锁相技术课程论文
论文题目:锁相环同步检波技术及在视频检波中的应用
专业:信息类
班级:信息092班
学号:
姓名:
指导教师:
2012年5月
锁相环同步检波技术及在视频检波中的应用
xxx
(中原工学院电子信息学院信息092班河南郑州)
摘要:早期电视机的大信号包络检波电路,后来在集成化的电视机中,视频检波又都采用同步检波方式。虽然这种同步检波比大信号包络检波电路有明显的改进,但还是存在一些不足,不能做到真正的同步。针对上述不足,一种先进的视频检波方式----锁相环同步检波,它可以克服上述的缺点,做到真正的同步。该检波方式在现代大屏幕彩色电视机的视频检波中取得很好的效果,并得到广泛应用。
关键词:检波;锁相环;同步检波;大屏幕彩电
Technique of PLL Synchronizing Demodulation and Application in Video Demodulation
(School of electrical information, Zhong Yuan College, Zheng zhou,451191, China)
Abstract: All circuits of demodulating strong signal envelope are adopted in previous TV’s video demodulation, synchronizing demodulations are widely in video demodulation in the later integrated TV set. Compared with strong signal envelope, synchronizing demodulation has a great improvement. However it still has some defects. Synchronization can not be realized. Aiming at above-mentioned shortage, PLL is a kind of advanced video demodulation described in this paper, it can resolve the above-mentioned problem. This method has been used in modern large screen color TV set widely, and has obtained a good result.
Keywords: demodulation; PLL; synchronizing demodulation; large screen color TV set
锁相技术是专门研究系统相位的技术。由于它的环路结构简单,性能良好,在许多新型电子设备,特别是在通信系统中,得到广泛的应用。锁相就是自动相位控制(APC),完成这一任务的负反馈环称为锁相环。锁相环的英文全称是 Phase-Locked Loop ,简称 PLL。它是一个闭环的相位误差控制系统,是将参考信号与输出信号之间的相位进行比较,产生相位误差电压来调整输出信号的相位,以达到与参