Design of a CORDIC Function Generator Using Table-Driven Function Evaluation with Bit-Level Truncation

• Main Authors: Wei-Cheng Hsu, 徐維誠
• Other Authors: Shen-Fu Hsiao
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/58221352228093812272

碩士 === 國立中山大學 === 資訊工程學系研究所 === 100 === Functional evaluation is one of key arithmetic operations in many applications including 3D graphics and stereo. Among various designs of hardware-based function evaluation methods, piecewise polynomial approximation is the most popular approach which interpolates the piecewise function curve in a sub-interval using polynomials with polynomial coefficients of each sub-interval stored in an entry of a lookup table ROM. The conventional piecewise methods usually determine the bit-widths of each ROM entry, multipliers, and adders by analyzing the various error sources, including polynomial approximation errors, coefficient quantization errors, truncation errors of arithmetic operations, and the final rounding error. In this thesis, we present a new piecewise function evaluation design by considering all the error sources together. By combining all the error sources during the approximation, quantization, truncation and rounding, we can efficiently reduce the area cost of ROM and the corresponding arithmetic units in the design of CORDIC processors.