Increasing the power efficiency of application specific instruction set processors using datapath optimization

Application specific instruction set processors (ASIPs) can be optimized both for speed and power taking advantage of the flexibility of a synthesized semi-custom implementation. The current case study evaluates the effect of datapath and instruction set optimisation using two examples from terrestrial digital video broadcasting (DVB-T) acquisition and tracking algorithms. Starting from a conventional, unoptimized instruction set architecture, which uses simple instructions like any commercially available DSP, incremental application specific optimizations are performed. Results in terms of cycle count and energy per task are used to evaluate the feasibility and the power efficiency of each implementation. The results show a huge potential (>6x) concerning power savings using this design methodology.