快速并行σ_i预测CORDIC算法

Fast Parallelizing σi Prediction CORDIC Algorithm

ＣＯＲＤＩＣ作为一种计算三角／双曲函数和向量旋转的迭代算法，其硬件结构简单，易于并行化处理和ＶＬＳＩ实现，因而在实时信号处理方面有广泛的应用前景。在ＣＯＲＤＩＣ算法中，旋转迭代方向σｉ的快速确定是提高算法运算速度的一个有效方法。文中从ＣＯＲＤＩＣ算法的基本思想出发，提出了一种并行σｉ预测算法，直接由输入数据确定迭代方向，同时提高了算法的并行化程度，在保证精度的情况下能大大缩短ＣＯＲＤＩＣ迭代算法的运算时间。

The CORDIC algorithm is well known as an efficient method for the computation of trigonometric/hyperbolic functions and vector rotations.The CORDIC iteration is directed by the rotation direction factor σi.Therefore the fast determination of σi is important to accelerate the speed of CORDIC processors.σi determination in redundant number system is not straightforword because an exact sign detection is not possible efficiently.Therefore,an predict algorithm of the original CORDIC is proposed which parallelize the σi determination and reduce the latency time of CORDIC algorithm considerably.