一种改进 CORDIC 算法的反正切计算

AnImproved Arctangent-Calculation for CORDIC Algorithm

传统流水线结构的坐标旋转数字计算(Coordinate Rotation Digital Computer,CORDIC)算法的迭代周期固定,在实现反正切函数运算时存在硬件资源消耗过多、输出时延较长等问题,提出一种基于查找表的改进的CORDIC算法。该方法不仅通过缩减有效数据位宽、合并迭代等手段节省了剩余角度Z路径的计算量,而且还消除了的增益因子的影响,有效的减小了硬件资源消耗及电路面积。分别使用matlab以及XILINX ISE进行理论建模分析仿真以及实际验证,结果表明:改进CORDIC算法在保证输出精度前提下,电路工作速度有一定提高,输出时延也有所减少,寄存器消耗节省50.6%,有效的降低了硬件资源消耗,适合实时性强、硬件资源有限的现代通信应用场合。

The iterative period of Coordinate Rotation Digital Computer (CORDIC) algorithm is fixed in the traditional pipeline structure. When the arctangent function is implemented, there are many problems such as excessive hardware resource consumption and long output delay,an improved CORDIC algorithm based on look up table was proposed. This method not only reduced the effective data bit width and merges iterations, but also eliminated the influence of gain factor, and effectively reduced the hardware resource consumption and circuit area. Theoretical simulation and practical verification were carried out in matlab and XILINX ISE, the conclusion shows that under the premise of ensuring the output precision, the improved CORDIC algorithm improves the circuit speed, reduces the output delay, saves 50.6% of the register consumption, and effectively reduces the hardware resource consumption.