Energy Efficient Quality Tunable CORDIC for DSP Applications on Battery Operated Portable Devices.

COrdinate Rotation DIgital Computer (CORDIC) is commonly utilized for the computation of cosine/sine i.e., the trigonometric functions, singular value decomposition, in digital signal processing (especially in image/video processing), etc. This paper introduces an energy efficient quality tunable CORDIC architecture that computes the cosine/sine values of any required angle in real-time, and is thus well suited for real time DSP applications, especially for image or video processing applications. The proposed architecture reduces the latency and overcomes data dependency by simultaneously performing all the five iterations, that may vary depending upon the desired energy efficiency. The novelty of this architecture is that, desired quality can be achieved by selecting one out of the available three modes. In order to assess the efficacy of the suggested architecture, some benchmark images are processed using the Discrete Cosine Transform (DCT) coefficients obtained via the proposed design. Energy saving is achieved at the cost of slight acceptable degradation in the output image quality. Further, the simulation results show that the proposed architecture is 92.3%, 2.8% and 49.08% more energy efficient than the existing basic, scale-free and lookahead CORDIC architectures, respectively.