nco的产生原理的相关代码；软件无线电、直接数据频 率合成器（DDS，Direct digital synthesizer）、快速傅立叶变换（FFT，Fast Fourier Transform） 等的重要组成部分，同时也是决定其性能的主要因素之一，用于产生可控的正弦波或余弦波。随着芯片集成度的提高、在信号 处理、数字通信领域、调制解调、变频调速、制导控制、电力电子等方面得到越来越广泛的应用-nco the generation principle of the relevant code　software radio, direct data frequency synthesizer (DDS, Direct digital synthesizer), Fast Fourier Transform (FFT, Fast Fourier Transform) and other important component, but also determine the performance of the main factors , controllable for generating a sine wave or cosine wave. With the improvement of chip integration, in signal processing, digital communications, modulation and demodulation, frequency control, guidance and control, power electronics, etc. to be more widely applied