Abstract
We present a high-radix Cordic rotation algorithm, which results in a reduction of the number of iterations. Carry-save representation is used and the selection function is performed by rounding, except for i=0 where a small table is necessary. The scale factor is not constant, but is efficiently computed in logarithmic form and compensated by a high radix exponential algorithm, where again we use selection by rounding. The algorithm proposed assures convergence for radices up to 1024. An architecture is presented and the execution time evaluated. A comparison with a radix-2 implementation demonstrates the speed-up achieved by the high-radix approach.
This work was supported in part by the Ministry of Education and Science (CICYT) of Spain under contract TIC92-0942 and Xunta de Galicia under contract XUGA-20606B93
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Antelo, E., Bruguera, J.D., Lang, T., Villalba, J., Zapata, E.L. (1996). High radix cordic rotation based on selection by rounding. In: Bougé, L., Fraigniaud, P., Mignotte, A., Robert, Y. (eds) Euro-Par'96 Parallel Processing. Euro-Par 1996. Lecture Notes in Computer Science, vol 1124. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0024698
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DOI: https://doi.org/10.1007/BFb0024698
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