CORDIC: Repensando Senos e Cossenos
     CORDIC: Rethinking sines and cosines

Ivana Mara Gomes Andersen Cavalcanti, Bene Régis Figueiredo, Pablo Diniz Batista, Edgar Monteiro da Silva

Resumo


A proposta deste trabalho é apresentar em detalhes um algoritmo iterativo via método de rotação vetorial, que exige basicamente operações de deslocamento de \textit{bit}, de adição e subtração para a realização de funções elementares básicas, conhecido como CORDIC. Tradicionalmente, diversos autores utilizam a abordagem matemática apresentada em 1959 por J. E. Volder \cite{Volder59}. Entretanto, será desenvolvida aqui, passo a passo, a ideia proposta no artigo para o cálculo de funções trigonométricas através de uma tabela de arco-tangentes sem a necessidade de operações de multiplicações e divisões. O algoritmo CORDIC possui grande potencial para utilização em hardware.

{Palavras-chave}: CORDIC, Linguagem C, rotação vetorial, microcontrolador.

Abstract:
The purpose of this paper is to present in detail an iterative algorithm via vector rotation method, which basically requires bit shift operations, addition and subtraction to perform basic elementary functions, known as CORDIC. Traditionally, many authors use the mathematical approach presented in 1959 by J.E. Volder \cite{Volder59}. However, here it will be developed, step by step, the idea proposed in the article for the calculation of trigonometric functions using an arc-tangent table without the need of multiplication and division operations. The CORDIC algorithm has great potential for use in hardware.


Keywords: CORDIC, C Language, rotation vector, microcontroller. 

Palavras-chave


CORDIC; linguagem C; rotação vetorial; microcontroladores

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Referências


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