摘要： 针对传统Cordic算法中迭代方向由剩余角度计算结果决定的缺陷，采用一种旋转方向预判断和校模因子改进的方法，在实现并行处理时由输入角二进制各位位值对迭代方向进行预测，可合并部分硬件电路，节省资源，提高算法运行速度和计算精度。实验结果表明，改进后的直接数字频率合成输出信号频谱杂散小且无杂散动态范围提高了20 dB，硬件资源比传统算法节约28％，计算误差达到10-5，该算法在速度、精度和资源低消耗上具有优势。

关键词: 改进型Cordic, 直接数字频率合成, 循环迭代, 方向预测, 现场可编程门阵列

Abstract: The direction of iterating is decided by the remaining angle results, taking the imported way of pre-determined of the direction of rotating and model factor, achieving the pre-determined of the iteration with the angle’ binary code, merging some of the hardware circuits and saving resources, improving the algorithm’s speed and accuracy. Experimental results show that the Direct Digital Synthesis(DDS) output signal spectrum spur is small and the Spurious Free Dynamic Range(SFDR) is improved by 20 dB, the hardware resources are saved by 28％, calculation error reaches 10-5 and effectiveness of these methods in speed, accuracy and low consumption is shown.

Key words: improved Cordic, Direct Digital Synthesis(DDS), loop iteration, direction prediction, Field Programmable Gate Array(FPGA)

中图分类号: 

• TN741