基于CORDIC算法的数字控制振荡器设计与实现

Design and Implementation of Digital Controlled Oscillator Based on CORDIC Algorithm

针对传统查表法占用ROM容量较高的不足,基于CORDIC算法代替ROM设计一种速度快、精度高、节约资源的数字控制振荡器的目的.采用了对CORDIC算法进行旋转迭代变换,对CORDIC算法进行角度预处理和FPGA流水线结构实现CORDIC算法的方法.通过QuratusⅡ和ModelSim软件的仿真测试,得出了数字控制振荡器的正交信号、幅值以及相角,即在16级流水线结构下,计数器和角度预处理正确运行,得到了完整的0~360°循环的正、余弦波形.

Aiming at the shortage of high ROM capacity occupied by traditional table lookup method,anumerically controlled oscillator with high speed,high precision and saving resources is designed based on CORDIC algorithm instead of ROM.The CORDIC algorithm is implemented by rotation iterative transformation,angle preprocessing and FPGA pipeline structure.Through the simulation test of QuratusⅡand ModelSim softwares,the orthogonal signal,amplitude and phase angle of the numerically controlled oscillator are obtained,that is,under the 16-stage pipeline structure,the counter and angle preprocessing are correctly operated,and the complete sine and cosine waveforms of 0~360°cycle are obtained.