direct digital frequency synthesizer meaning in Chinese
直接式数字频率合成器
Examples
- Study on direct digital frequency synthesizer technology based on piecewise pperation
基于分段运算的直接频率合成技术研究 - At first , this paper described the basic structure , working principle , sources of spurious signals and characteristics of output spectrum , of direct digital frequency synthesizer ( dds )
首先分析直接数字频率合成器( dds )的基本结构、工作原理、杂散来源、输出频谱特性。 - Direct digital frequency synthesizer ( dds ) is an apparatus to generate wave on the required frequency . it provides high frequency resolution , rapid frequency transforma - tion and other superiority
直接数字频率合成器是现代频率合成的主要工具,它有频率分辨率高,频率转化快等众多优点。 - Then according to the emphasis of the design , went deeply into the theory of pll frequency synthesizers widely used , described pll ’ s working principle , structure and several types in detail , and made research and analysis of pll frequency synthesizers ’ phase noise , including the effect of the active loop filter on the phase noise , and give some methods to make improvement as well , such as changing loop filter form , reducing divide number , and increase phase detector frequency , etc . then paper introduced the principle character and phase noise analysis of direct digital frequency synthesizer ( dds ) and injection phase lock circuit , which are also important circuits in the design
论文首先对几十年频率合成器的发展进行概述,而后针对本次设计的重点,对应用较为广泛的锁相频率合成理论进行了深入的探讨,详细介绍了锁相环的工作原理、组成结构和锁相类型,并对锁相频率合成器的相噪特性进行了研究分析,包括有源环路滤波器对于相噪的影响,提出了改善相位噪声的几点措施:改善环路形式、降低分频数、增大鉴相频率等。接着介绍了直接数字频率合成器( dds )和注入锁相电路的原理特点以及相噪分析,它们也是本次设计的重要电路。 - The direct digital frequency synthesizer is a kind of fully digitized frequency synthesizer , which consists of the phase accumulator , the sine look - up table , the digital to analog converter and the low band filter . it is of high frequency resolution , fast frequency switching speed , low phase noise , the ability to switch frequencies while maintaining constant phase , and the ability to producing arbitrary waveforms
直接数字频率合成器是一种全数字化的频率合成器，由相位累加器、波形rom 、 d a转换器和低通滤波器构成， dds技术具有频率分辨率高、频率切换速度快、频率切换时相位连续、输出相位噪声低和可以产生任意波形等优点。