Performance and security analysis of novel ZCCRW codes in lower earth orbit based MDM-OWC incorporating hybrid modulations

Explosive data rate requirements in the satellite communication for surveillance, military services, and broadcasting have put peer pressure on the optical wireless communication (OWC) systems. Secure data transmission against eavesdropper and performance enhancement at authentic user is major concern these days. In this work, performance and security analysis of spectral amplitude codes (SAC) in mode division multiplexed (MDM) OWC have been carried out and a novel zero cross correlation resultant weight (ZCCRW) code at 100 Gbps capacity has been presented. Random diagonal (RD), Enhanced double weight (EDW), Diagonal double weight (DDW) codes have been compared through simulations and also mathematical expressions are derived under the effects of eavesdropper. Hybrid modulations have been compared to check optimal modulation with combination of Laguerre-Gaussian (LG), and HermiteGaussian (HG) modes. Results have revealed that ZCCRW code with MD-DQPSK using LG modes provide best performance and least susceptibility to eavesdropper.