Design and Analysis of Extension-Rotation CORDIC Algorithms based on Non-Redundant Method

International Journal of Signal Processing, Image Processing and Pattern Recognition, Vol. 5, No. 1, March, 2012In this paper, rotation-extension CORDIC methods, i.e. double-rotation and triple-rotation, are proposed for the objective of improving the performance and accuracy of the CORDIC computational algorithm in radix-2. In the double-rotation and triple-rotation\ud methods, the convergences of the CORDIC computations are accelerated by duplicating and triplicating the micro-rotation angles to be 2 and 3 , respectively. The non-redundant\ud mechanism, where a rotation direction is in a set of 1 and -1, depending on an intermedi-\ud ate converging parameter (either y or z), is applied to constant scaling factors. Convergence range and accuracy of elementary functions hardware performed by using the CORDIC methods in rotation mode and vectoring mode on the circular, hyperbolic, and linear coordinate systems are examined, investigated and compared to Matlab/Simulink simulation results. The comparison results show that the proposed CORDIC methods provide higher computational accuracy than the conventional one at the same number of iterations. A high precision CORDIC algorithm is introduced and evaluated for VLSI implementation. Finally, speed and area performance of the CORDIC hardware based on the pipeline (unfolded) digit-parallel architecture of the proposed CORDIC methods are compared to the CORDIC methods previously published in the literature