Low latency pipelined circular CORDIC

The pipelined CORDIC with linear approximation to rotation has been proposed to achieve reductions in delay, power and area; however, the schemes for rotation (multiplication) and vectoring (division) complicate implementation in a single unit. In this work, we improve the linear approximation scheme, leading to a unified implementation for rotation and vectoring where fully parallel tree multipliers are used instead of the second half of CORDIC iterations. We also combine the linear approximation to rotation with the scale factor compensation so that the compensation is performed concurrently with the rotation process. Comparison with other designs is also provided.