Performance Comparison of All-Optical Amplify-and-Forward Relaying FSO Communication Systems With OOK and DPSK Modulations

Abstract

All-optical amplify-and-forward (OAF) relaying technique can amplify and filter the attenuated optical signal in optical domain, and thus is regarded as a simple way to extend the transmission distance of free-space optical (FSO) communication systems. At the relaying node, however, the incident background radiation and the amplified spontaneous emission noise of the deployed erbium-doped fiber amplifier will deteriorate the optical signal-to-noise, therefore causing the degradation of the system's bit error ratio (BER). In this paper, we perform simulations and experiments on FSO system with on-off keying (OOK) and differential phase-shift keying (DPSK) signals, focusing on the receiving sensitivity loss (RSL) of the OAF-assisted dual-hop system. Taking the BER level of 10 −7 as the reference, we find that the DPSK system suffers more than 8 dB RSL at the data rate of 5 Gb/s in simulation, while the OOK system gets less than 1 dB RSL at the same data rate. In the following experiments, the obtained results exhibit that RSL of DPSK system is nearly 10 dB, which of OOK system is less than 1.5 dB, shown similarly property to the simulations.

Relay-Assisted Technology in Optical Wireless Communications: A Survey

“…Fig. 9 shows the different relay forms about all-optical OOWC systems [145]- [149]. The basic form of the dual-hop is as shown in Fig.…”

“…9 (a). In [145], the all-optical dual-hop OOWC link is proposed, which is to better realize the effectiveness and reliability of communications. Relay configurations have two ways: serial (that is, multi-hop transmission) and parallel (namely are some barriers in the direct link, the communications will be cut off.…”

Performance Analysis of Hybrid Radio Frequency and Free Space Optical Communication Networks with Cooperative Spectrum Sharing

“…By Gauss Laguerre quadrature rule, the average bit error rate was achieved in double generalized gamma fading environments. Through professional simulation software Op-tiSystem 11, the effects of incident background radiation and spontaneous emission noise on the all optical relaying systems at a data rate of 5 Gb/s were considered in [5] for on off keying and differential phase shift keying constellation. A similar optical link construction was considered in a millimeter wave scenario [6], where a fluctuating two-ray fading model was established in millimeter wave link.…”

Performance enhancement of an FSO link using polarized quasi-diffuse transmitter

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