The Research on Evolutionary Hardware Evolution Algorithm for Stall Effect

The fitness values increase rapidly in the early stages of circuit evolution design, while the fitness values grew slowly or stagnated, at the later stages of the evolution. The phenomenon is called the "Stalling effect" phenomenon. In response to this problem, the evolutionary redundancy repair technique of circuit evolution design is proposed. The repair module is built using the redundant nodes and activated nodes at the later of circuit evolution design. The circuit with partially correct functions is evolved using Cartesian Genetic Programming at the early stages of the algorithm. At the later stages of the algorithm, the repair modules repair the error output of minimum items, ensure the correct output of the minimum items not modified meanwhile. The target circuit obtained traditional repair techniques include the additional repair circuit modules and the partial correct circuit. The evolutionary redundancy repair technique combines the repair circuit module and the evolution circuit. The repair module is built through the redundant nodes and the activated nodes. The experiment of a three-bit multiplier is researched. The results show that the rate of convergence of evolution program is greatly accelerated.