On-line CORDIC algorithms

Abstract

The CORDIC algorithms provide a fast way to calculate a number of basic arithmetic functions. A CORDIC calculation takes O(n) steps for a function, where n is the word length of the operands. The speed is limited by the carry propagation in the adders and the I/O throughput. Speed can be improved by introducing redundancy in the calculation circuitry and I/O throughput by doing I/O transfers while calculating. The latter is characteristic for the class of so-called online arithmetic. At the same time, the pin requirements are limited to a single digit per operand. The authors introduce a number of new algorithms that provide an online CORDIC implementation.<>