Hybrid WDM-FSO-PON with integrated SMF/FSO link for transportation of Rayleigh backscattering noise mitigated wired/wireless information in long-reach

Abstract

This paper presents a hybrid Wavelength division multiplexing-free space optics-passive optical network for bidirectional transmission with 4×10 Gbps downlink and 2×10 Gbps uplink to provide information to the wired and wireless users simultaneously over total 60 km SMF and 650 m FSO or 62 km SMF link with enhanced fault protection capability. Noise tolerance against Rayleigh backscattering (RB) also enhanced by employing two different ports of interleavers and by allowing different wavelengths of light as carrier signals for uplink and downlink transmission through a single feeder fiber. Integrated single mode fiber (SMF)/free space optics (FSO) link increase the reliability against failure of any one channel between SMF and FSO link, besides that it maintains the continuity of data transfer even where fiber link installation is restricted due to environmental boundary such as between two mountains, wide river etc. Low bit error rate (10−9), <1 dB power penalties (0.7 dB, 0.85 dB, 0.9 dB) are obtained between B2B and over total transmission link. A comparison between our proposed network and the network when the signal transmitted over total transmission link (60 km SMF+ 650 m FSO, or 62 km SMF) at a time also verified with their power budgets. Divergence losses at different FSO lengths (17 m to 680 m) are also calculated to determine the maximum possible FSO length for this proposed set up. Therefore, the proposed architecture proofs its feasibility, reliability and the capacity to continue transfer of high data rate over long distance even in the unfair environmental situation, which makes it an attractive platform to the next generation communication system (5G) to fulfill the thirst of end users.