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# A Unified View of CORDIC Processor Design

## Abstract

The COordinate Rotation Digital Computer (CORDIC) algorithm is a well-known and widely studied method for plane vector manipulation. It uses a sequence of partial vector rotations to approximate the expected one. Under different operating modes, this algorithm can be used either to do Givens transformation for vector rotation and vectoring or to evaluate more than a dozen of elementary, trigonometric, and hyperbolic functions. CORDIC processors are therefore powerful computing systems for applications involving large amount of rotation operations and mathematical functions mentioned above.

CORDIC computation adopts only primitive arithmetic operations (additions, subtractions, and shiftings) instead of multiplications. This has a great impact on the hardware characteristics especially when circuit complexity is concerned. As a consequence, the CORDIC algorithm is become a widely used approach for elementary function evaluation whenever the silicon area is a primary constraint. The main drawback is the intrinsic low performance due to the iterative computational approach. In particular, parallelism cannot be easily introduced since each CORDIC iteration has to select the rotation direction by analyzing the result of the previous one.

In this chapter, a unified view of the CORDIC architecture design is presented. Our goal is to provide a wide spectrum of architectures, a coordinated and comprehensive design methodology, and the main figures of merit characterizing performance and complexity. This methodology contains the basic guidelines for designers to choose an approach with respect to specific requirements and constraints of the application.

### Keywords

Radar Sine Dinate Acoustics Como## Preview

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