Compact and Energy Efficient QCA Based Hamming Encoder for Error Detection and Correction

Abstract

Quantum-dot Cellular Automata (QCA) are preferred for realizing logic circuits at nanoscale dimensions along with a high level of integration and minimal energy consumption. Hamming code is a set of entropy codes used for error detection and correc- tion in communication systems. Error detection and correction is carried out with the help of parity bits which are appended with the original bits. Designing a Hamming encoder in nanoscale has its own merits such as optimized area, reduced energy dissipation and lower QCA cost. This work proposes two QCA-based (7, 4) Hamming encoder designs; multilayer (proposed- 1) and coplanar (proposed-2) structure with area and energy analysis. Proposed-1 encoder has achieved reduction of cell area by 12.5 %, 34.58 % in terms of cell count, and reduction in total energy dissipation of 26.8 % when compared to reference encoder. Proposed- 2 encoder has achieved reduction of 18.75 % in area, 44.15 % in terms of cell count, and 16.5 % in total en- ergy dissipation when compared to reference encoder. In terms of QCA cost, reduction of 12.5 % is achieved in case of proposed structures. The energy dissipated in the proposed designs is less compared to reference encoder. Proposed-2 structure is more efficient com- pared to multilayer and reference encoder in terms of cell count, cell area and QCA cost. The QCA circuits are realized in QCADesigner and analyzed energy in QCADesigner-E.