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arXiv · 1808.10277

On the Performance of a Relay-Assisted Multi-Hop Asymmetric FSO/RF Communication System over Negative Exponential atmospheric turbulence with the effect of pointing error

Mohammad Ali Amirabadi
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Abstract

In this paper, a multi-user multi-hop hybrid FSO / RF system is presented. This structure is consisted of two main parts. The main motivation of presenting this structure is communication in long-range impassable links or some specific atmospheric conditions under which RF connection becomes easily disrupted. Although these effects could be mitigated by consuming more power or adding processing complexity, but a small user mobile phone cannot deserve more complexity or power supply. The fact that FSO and RF links are complementary of each other brings a new solution in mind; an access point that amplifies received signal via short-range RF link and forwards it to via long-range FSO link, could solve the mentioned problem. This scenario is exactly implemented at the first part of the proposed structure. At the second part, a multi-hop hybrid parallel FSO / RF link is implemented to connect source and destination Base Stations. It is the first time that in a multi-hop FSO / RF system, multi-user scheme, signal selection at each hop, known and un-known CSI in amplify and forward relaying, and saturate atmospheric turbulence with the effect of pointing error are considered. New expressions are derived in closed-form for Bit Error Rate (BER) and Outage Probability of the proposed structure and verified by MATLAB simulations. The proposed structure has advantages of FSO, RF, relay-assisted, and multi-user systems at the same time. Results indicate that it has low dependence on number of users and number of relays. Therefore, it is suitable for areas with varying population and long-range links. This structure offers independent performance without additional power consumption, processing latency, and complexity.

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BibTeXRIS

Mohammad Ali Amirabadi. 2018-11-20. On the Performance of a Relay-Assisted Multi-Hop Asymmetric FSO/RF Communication System over Negative Exponential atmospheric turbulence with the effect of pointing error. https://arxiv.org/abs/1808.10277

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