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Higher Radix Square Root with Prescaling
August 1992 (vol. 41 no. 8)
pp. 996-1009

A scheme for performing higher radix square root based on prescaling of the radicand is presented to reduce the complexity of the result-digit selection. The scheme requires several steps, namely multiplication for prescaling the radicand, square root, multiplication for prescaling for the division, and division. Online algorithms are used to reduce the overall time and pipelining to reuse the different modules. An estimate of the execution time for a radix-256 unit for double-precision square root and a comparison with other implementations indicate that the proposed approach is an alternative to consider when designing a square-root unit.

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Index Terms:
online algorithms; higher radix square root; prescaling; radicand; complexity; result-digit selection; multiplication; division; pipelining; double-precision square root; digital arithmetic; dividing circuits; multiplying circuits; number theory.
T. Lang, P. Montuschi, "Higher Radix Square Root with Prescaling," IEEE Transactions on Computers, vol. 41, no. 8, pp. 996-1009, Aug. 1992, doi:10.1109/12.156542
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