DocumentCode :
1199833
Title :
Modified virtually scaling-free adaptive CORDIC rotator algorithm and architecture
Author :
Maharatna, Koushik ; Banerjee, Swapna ; Grass, Eckhard ; Krstic, Milos ; Troya, Alfonso
Author_Institution :
Dept. of Electr. & Electron. Eng., Univ. of Bristol, UK
Volume :
15
Issue :
11
fYear :
2005
Firstpage :
1463
Lastpage :
1474
Abstract :
In this paper, we proposed a novel Coordinate Rotation Digital Computer (CORDIC) rotator algorithm that converges to the final target angle by adaptively executing appropriate iteration steps while keeping the scale factor virtually constant and completely predictable. The new feature of our scheme is that, depending on the input angle, the scale factor can assume only two values, viz., 1 and 1/√2, and it is independent of the number of executed iterations, nature of iterations, and word length. In this algorithm, compared to the conventional CORDIC, a reduction of 50% iteration is achieved on an average without compromising the accuracy. The adaptive selection of the appropriate iteration step is predicted from the binary representation of the target angle, and no further arithmetic computation in the angle approximation datapath is required. The convergence range of the proposed CORDIC rotator is spanned over the entire coordinate space. The new CORDIC rotator requires 22% less adders and 53% less registers compared to that of the conventional CORDIC. The synthesized cell area of the proposed CORDIC rotator core is 0.7 mm2 and its power dissipation is 7 mW in IHP in-house 0.25-μm BiCMOS technology.
Keywords :
VLSI; adaptive signal processing; approximation theory; convergence of numerical methods; digital arithmetic; digital signal processing chips; iterative methods; CORDIC rotator algorithm; DSP; VLSI; approximation datapath; binary representation; convergence; coordinate rotation digital computer; digital signal processing; iteration nature; target angle; vector rotation; very large-scale integration; Arithmetic; Computer architecture; Convergence; Digital signal processing; Discrete Fourier transforms; Discrete cosine transforms; Fast Fourier transforms; Hardware; Signal processing algorithms; Space technology; Coordinate rotation digital computer (CORDIC); digital signal processing (DSP); scaling-free CORDIC; vector rotation; very large-scale integration (VLSI);
fLanguage :
English
Journal_Title :
Circuits and Systems for Video Technology, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8215
Type :
jour
DOI :
10.1109/TCSVT.2005.856908
Filename :
1522271
Link To Document :
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