Table 2: Comparison of various rotational CORDIC architectures, (SD: signed digit, CS: carry save).
 Method (year) Radix, $\rho$ Arithmetic Latency $\left({t}_{\text{FA}}\right)$ Iterative Iterative Scale factor Nonpipelined Pipelined $X/Y$ path $Z$-path $K$ Nonredundant (1959) [3] $2$ 2's compliment ${n}^{2}$ ${n}^{2}$ $\surd$ $\surd$ Constant Redundant (1987) [42] $2$ CS $n{t}_{\text{stage}}$ $n{t}_{\text{stage}}$ $\surd$ $\surd$ Variable Double-rotation/ $2$ SD $1.5n{t}_{\text{stage}}$ $1.5n{t}_{\text{stage}}$ $\surd$ $\surd$ Constant Correcting (1991) [51] Low latency (1992) [55] $2$ CS $\left(n+{\mathrm{log} }_{3}n-1\right){t}_{\text{stage}}$ $\left(\left(9n-3\right)/8\right){t}_{\text{stage}}$ $\surd$ $\surd$ Constant Branching (1993) [52] $2$ SD $n{t}_{\text{stage}}$ $n{t}_{\text{stage}}$ $\surd$ $\surd$ Constant DCORDIC (1996) [56] $2$ SD/CS — $\left(n{t}_{\text{stage}}+n+1\right)$ $\surd$ $\surd$ Constant Radix-4 (1993) [58] $4$ SD — $\left(3n/4+1\right){t}_{\text{stage}}$ $\surd$ $\surd$ Variable Radix2-4 (1996) [59] $2\text{–}4$ CS — $\left(3n/4+1\right){t}_{\text{stage}}$ $\surd$ $\surd$ Constant Radix-4 (1997) [43] $4$ CS — $\left(2n/3+1\right){t}_{\text{stage}}$ $\surd$ $n/6$ Variable PCORDIC (2002) [61] $2$ SD $\left(1.7n+1.25+{\mathrm{log} }_{2}n\right)$ — $\surd$ $×$ Constant Flat CORDIC (2002) [63] $2$ SD 34 for 16-bit, 50 for 32-bit — combinational $×$ Constant Para-CORDIC (2004) [64] $2$ CS $\left(2\left(s\left(n\right)+n/2-l+2\right)+⌈{\mathrm{log} }_{1.5}n+2⌉\right)$ — $\surd$ $×$ Constant Semi-flat (2006) [65] $2$ SD 33 for 16-bit — $\lambda /$combinational $\lambda$ Constant Nonredundant low-latency (2008) [49] $2$ 2's compliment — $\left(n/2+2\right){t}_{\text{adder}}$ + ${t}_{\text{multiplier}}$ $\left(n/2+1\right)/$multiplier $n/3$ Constant