Performance Analysis of Shift ZCC Codes and Multi Diagonal Codes in 100 Gbps MDM-FSO System

Abstract

Abstract With the rapid growth in the internet applications, pressure is observed on the optical communication systems. Free space optical communication (FSO) is very important alternative to the optical fiber because of elimination of licenses, trenching, and no cost of ways and saves the time of installation. Wavelength division is capacity enhancement multiplexing but due to large number of laser requirements, it becomes expensive. Mode division multiplexing (MDM) is suitable multiplexing technique because it needs only single laser and can support high data rates. Optical code division multiplexing and MDM is demonstrated in this work at 100 Gbps over FSO supporting 10 users. Multiple access interference is prominent issue in OCDMA codes and in order to suppress MAI, zero cross correlation codes are used and use of Laguerre Gaussian modes has been done. Different fog conditions are analyzed and two different OCDMA cods are incorporated as well as compared in the proposed system such as shift zero cross correlation codes and multi diagonal codes in terms of Q factor and BER.