Hybrid Wordlength Optimization Methods of Pipelined FFT Processors

Quickly and accurately predicting the performance based on the requirements for IP-based system implementations optimizes the design and reduces the design time and overall cost. This study describes a novel hybrid method for the word-length optimization of pipelined FFT processors that is the arithmetic kernel of OFDM-based systems. This methodology utilizes the rapid computing of statistical analysis and the accurate evaluation of simulation-based analysis to investigate a speedy optimization flow. A statistical error model for varying word-lengths of PE stages of an FFT processor was developed to support this optimization flow. Experimental results designate that the word-length optimization employing the speedy flow reduces the percentage of the total area of the FFT processor that increases with an increasing FFT length. Finally, the proposed hybrid method requires a shorter prediction time than the absolute simulation-based method does and achieves more accurate outcomes than a statistical calculation does.