Meghdad Aynehband - Faculty member of Hendijan campus, Mahshahr Branch, Islamic Azad University, Mahshahr, Iran
Ali Mokhtarbaf - Faculty member of Islamic Azad University, Baghmalek branch, Baghmalek, Iran
Houman Zarrabi - Faculty member of ICT Research Institute, Tehran, Iran

Trigonometric functions are widely used in digital signal processing. CORDIC (COordinate Rotation DIgital Computer) algorithm was presented as some of best ways to calculate these functions to any desired angle. CORDIC method is a sequential algorithm and for reaching a circuiting behavior must be rotated several times.CORDIC algorithm design in the face of the delay is very high. The lack of accuracy in the binary processor’s design motivate researchers to decimal processors,explicit value of some fractionsuch as. Although considerable research has been devoted to binary CORDIC techniques, rather less attention has been paid to decimal CORDIC and its improvement. This research improves convergence system speed by changing control algorithm by adding a small unit in the input circuit hardware and therefore its response time has increased. By the way with insert an RNS adder and angles table’s modification, the researchers were achieved to more calculation speed. The significant optimization is provided, especially on the small angles about 12 degrees, demonstrated improvement up to 6.62%.

CORDIC, decimal, transcendental functions, redundant adder