Patent ID: 6480871
Filing Date: 2002-11-12
Classification: G06F

Abstract:
A method for high speed evaluation of the sine and cosine of input values using a CORDIC algorithm to produce output values, wherein the input values and output values are accurate up to any fixed precision by performing a sequence of zeroing and rotation operations, the improvements comprising:a) initializing said input values to provide initialized values; b) zeroing and rotating said initialized values to produce a set of intermediate values; and c) iteratively zeroing and rotating said set of intermediate values no more than &LeftCeiling;n+32&RightCeiling;â€ƒtimes to achieve an output precision of at least n bits, where n is an integer, n=1, 2 . . . , to produce subsequent sets of intermediate values, said zeroing operation utilizing pre-computed sums and differences of two successive elementary angles arctan 2âˆ’2i and angles arctan 2âˆ’(2i+1) in each iteration i, for i=0, 1, . . . , &LeftCeiling;n+32&RightCeiling;.&it;â€ƒ