Improving the throughput of flexible-precision DSPS via algorithm transformation

In this paper, we have presented a systematic technique to improve throughput of signal/image processing algorithms when implemented on flexible precision hardware. Many image/signal processing algorithms need 8-16 bit precision while the DSPs available are of much higher precision (32bit). Significant performance gain can be obtained if multiple low precision computations can be performed in one cycle of a high precision DSP. We have proposed a framework based on algorithm transformation techniques of unfolding and retiming to systematically map low precision algorithms onto high precision DSPs. The improvement in throughput obtained by this framework is linearly related to the ratio of precision used by the processor and that required by the algorithm. The efficacy of this technique has been demonstrated on a IIR filter. We have also established some theoretical bounds on the maximum throughput that can be achieved using the proposed methodology.