Design of a Novel Comparator Based on Modified GDI in QCA Technology for Biometric Authentication

Abstract

Biometric authentication techniques play a crucial role in enhancing data and information security. Quantum-Dot Cellular Automata (QCA) has emerged as a powerful alternative to CMOS technology, offering significant advantages such as high density, low power consumption, and high operational speed, thus potentially enhancing the security of nano-communications. This paper presents the design of a novel comparator circuit in QCA technology utilizing the Modified Gate Diffusion Input (MGDI) technique, followed by its application in a fingerprint-based authentication system. By reducing the number of cells and required space, the proposed circuit enhances the efficiency and speed of authentication systems. Designed with only 10 cells in a single layer and a single clock phase, the proposed circuit demonstrates a 16% improvement in cell count and a 33% reduction in quantum cost compared to previous works, as verified through simulations performed using QCADesigner software. The development of the proposed block in 2x2 and 4x4 comparator circuit designs shows that the proposed scheme is scalable to higher bit counts for authentication purposes.