On the Performance Analysis of Multi-Hop Hybrid FSO/RF Systems Using DPSK-SIM Over Gamma-Gamma Turbulence Channel

This paper presents a hard switching decode and forward multihop hybrid free-space optical and radio frequency (FSO/RF) system. We aim to get better performance by changing modulation. The FSO channel is modeled using Gamma-Gamma distribution under IM/DD with Differential Phase Shift Keying Subcarrier Intensity Modulation (DPSK-SIM) scheme. The RF channel is modeled using Nakagami-m distribution. We derive a closed-form expression for the outage probability of the multi-hop FSO link using DPSK-SIM and consider the system performance under various haze weather conditions, including the impact of the number of hops, pointing error, and link distance. Finally, the performance of the DPSK-SIM is compared with the performance of phase-shift keying (PSK) modulation. The outcomes confirm that the DPSK-SIM scheme improves under different haze weather conditions, pointing error displacement (jitter), and hop to hop link distance. CCS CONCEPTS • Hardware → Integrated circuits; Interconnect; Photonic and optical interconnect.