Dds is used to achieve fine resolution , while injection phase lock circuit is used to realize low phase noise high performance input reference frequency Dds用于实现小步进,而注入锁相电路则用来产生低相噪的高性能参考源。
For example , when the speed of transporting is very low , it is very difficult to track the receiver signal frequency through the common phase locked loop 如在传输数据速率较低时,普通锁相环来跟踪接收信号频率则很困难。
Lut was replaced by the method taking triangle wave and differential in the line phase locked circuit , so it saves the hardware area and cost 在行锁相中,用取三角波然后差分的方法替换了查找表,减小了芯片面积,降低了成本。
Chapter 2 discusses the principle of pll ( phase locked loop ) . the emphasis is placed on the analysis of two orders pll adopting active proportion integral filter 第二章主要讲述了锁相环的工作原理,着重于理想二阶锁相环的分析。
In addition , this paper analyzes the noise - filtering quality of phase locked loop , a / d transformation theory , and the combination and quality of the decimation filter 并对锁相环对噪声的过滤性能、 a / d转换原理和抽取滤波的组成及性能进行了深入地分析。
Considering the effect of line phase locked , a front modulation is added in color subcarrier regeneration hardware module to improve the module ’ s precision 考虑到行锁相对色副载波还原的影响,在硬件实现时增加了前向调节的功能,提高了色副载波还原的精度。
Pll referred in this thesis is aimed to generate system clock . the concept of phase locking was invented in the 1930s and swiftly found wide usage in electronics and communication 自从上世纪30年代锁相理论被提出后,锁相环在电子、通讯等领域得到了迅速而广泛的应用。
We designed a frequency scouting loop by the technology of phase locked loop , and then simulate . 4 . do some researches on influence of phase shift in frequency estimate 以锁相环技术为基础,构建了一个差错控制信号,设计了一个频率跟踪环,来实现对频率的跟踪,并通过了仿真试验。
Chapter 2 discusses the modulation and demodulation theory and the principle of pll ( phase locked loop ) from the general communication theory to several modern modulation techniques 从通信传输的一般原理到几种具体的现代调制技术,并针对dvb - s接收芯片简要叙述了qpsk的解调原理。
After briefly introducing the correlated technical basis of analog wireless video transmission system , the paper mainly focuses on the theory of oscillator and pll ( phase lock loop ) 论文首先简要介绍了模拟无线视频传输系统的相关技术基础,然后着重讨论了振荡器和锁相环的相关理论。