A regular network of symmetric functions in quantum-dot cellular automata

Quantum-dot cellular automata (QCA) is a technology which has the potential of faster speed, smaller size and minimum power consumption compared to transistor based technology. In quantum-dot cellular automata, the basic elements are simple cells. The cells are used to construct majority voter gate, inverter and wire. This paper utilizes the unique characteristics of QCA majority voter gate to realize symmetric functions. In this paper, we introduce a synthesis technique for implementing totally symmetric Boolean functions using Quantum-dot Cellular Automata (QCA) logic. First, a simple regular module is designed to synthesize unate symmetric functions. The structure uses 3-input majority voter gates. General symmetric Boolean functions are then realized following a unate decomposition method. We study the synthesis of some well known benchmark symmetric functions using the proposed method. The designs are simulated and the simulation result indicates the complexity, area and delay of the proposed designs.