Real-Time and High-Accuracy Arctangent Computation Using CORDIC and Fast Magnitude Estimation
AbstractThis paper presents an improved VLSI (Very Large Scale of Integration) architecture for real-time and high-accuracy computation of trigonometric functions with fixed-point arithmetic, particularly arctangent using CORDIC (Coordinate Rotation Digital Computer) and fast magnitude estimation. The standard CORDIC implementation suffers of a loss of accuracy when the magnitude of the input vector becomes small. Using a fast magnitude estimator before running the standard algorithm, a pre-processing magnification is implemented, shifting the input coordinates by a proper factor. The entire architecture does not use a multiplier, it uses only shift and add primitives as the original CORDIC, and it does not change the data path precision of the CORDIC core. A bit-true case study is presented showing a reduction of the maximum phase error from 414 LSB (angle error of 0.6355 rad) to 4 LSB (angle error of 0.0061 rad), with small overheads of complexity and speed. Implementation of the new architecture in 0.18 µm CMOS technology allows for real-time and low-power processing of CORDIC and arctangent, which are key functions in many embedded DSP systems. The proposed macrocell has been verified by integration in a system-on-chip, called SENSASIP (Sensor Application Specific Instruction-set Processor), for position sensor signal processing in automotive measurement applications. View Full-Text
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Pilato, L.; Fanucci, L.; Saponara, S. Real-Time and High-Accuracy Arctangent Computation Using CORDIC and Fast Magnitude Estimation. Electronics 2017, 6, 22.
Pilato L, Fanucci L, Saponara S. Real-Time and High-Accuracy Arctangent Computation Using CORDIC and Fast Magnitude Estimation. Electronics. 2017; 6(1):22.Chicago/Turabian Style
Pilato, Luca; Fanucci, Luca; Saponara, Sergio. 2017. "Real-Time and High-Accuracy Arctangent Computation Using CORDIC and Fast Magnitude Estimation." Electronics 6, no. 1: 22.
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