Design of optical quaternary adder and subtractor using polarization switching

Abstract

The replacement of binary logic with the multi-valued logic based (MVL) system in the optical domain might be the way to fulfill the demand of faster data computing with a huge amount of data handling capability. Quaternary logic is one of the most promising MVL. In this article, the authors have proposed a new method of developing optical adder and subtractor based on quaternary logic. The frequency encoding technique is used here for data representation because of its inherent property of constancy during reflection, refraction, and transmission. So that, instead of any fluctuation in intensity, different bits can be processed or communicated without any error and thus, the bit error rate can be minimized which makes the scheme novel one. Polarization switching characteristics of semiconductor optical amplifier are adopted here to develop these basic units. The simulative studies on PSW clarify the optical switching mechanism of it. The optical circuits of quaternary adder and subtractor are also testified with simulation results for different cases and thus the admissibility of the proposed scheme is enhanced.