The Double Rotation CORDIC Algorithm: New Results for VLSI Implementation of Fast Sine/Cosine Generation

Abstract

The COordinate Rotation DIgital Computer (CORDIC) algorithm is an arithmetic algorithm to evaluate various elementary functions through a series of iterative operations. In this paper, a high-speed sine/cosine generator is based on double rotation of the original CORDIC algorithm by predicting all the rotation directions from the initial input angle. The proposed architecture has a simple prediction scheme through an efficient determination strategy of rotation direction. The critical delay path is reduced by utilizing the carry-save adder (CSA). Thus, the computation complexity of the proposed architecture is evaluated; the proposed architecture improves the latency of 37.5% in 16-bit operand, 40.6% in 24-bit operand and 42.5% in 32-bit operand, respectively. While in the large number-bit operand, the speed should be improved by 48%.