4 Bit Comparator Design Based on Reversible Logic Gates

Today, reversible logic circuits has attracted considerable attention in improving some fields like nanotechnology, quantum computing, and low power design. In this paper 4 bit reversible comparator based on classical logic circuit is represented which uses existing reversible gates. In this design we try to reduce optimization parameters like number of constant inputs, garbage outputs, and quantum cost. The results show that, the proposed comparator has 4 quantum cost and one constant input less than the prior design. 1