The exponential increase in the number of mobile users, coupled with the strong
demand for high-speed data services results in a significant growth in the required cellular backhaul capacity. Optimizing the cost efficiency while increasing the capacity
is becoming a key challenge to the cellular backhaul. It refers to connections between
base stations and mobile switching nodes over a variety of transport technologies such
as copper, optical fibers, and radio links. These traditional transmission technologies
are either expensive, or cannot provide high data rates. This work is focused on the
opportunities of free-space-optical (FSO) technology in next generation cellular back-
haul. FSO is a cost effective and wide bandwidth solution as compared with the
traditional radio-frequency (RF) transmission. Moreover, due to its ease of deployment,
license-free operation, high transmission security, and insensitivity to interference,
FSO links are becoming an attractive solution for next generation cellular networks.
However, the widespread deployment of FSO links is hampered by the atmospheric
turbulence-induced fading, weather conditions, and pointing errors. Increasing the
reliability of FSO systems, while still exploiting their high data rate communications,
is a key requirement in the deployment of an FSO-based backhaul. Therefore, the aim
of this work is to provide different approaches to address these technical challenges. In
this context, investigation of hybrid automatic repeat request (HARQ) protocols from
an information-theoretic perspective is undertaken. Moreover, performance analysis
of asymmetric RF/FSO dual-hop systems is studied. In such system models,
multiple RF users can be multiplexed and sent over the FSO link. More specifically, the end-to-end performance metrics are presented in closed-form. This also has increased
the interest to study the performance of dual-hop mixed FSO/RF systems, where the
FSO link is used as a multicast channel that serves different RF users. Having such
interesting results motivates further the analysis of dual-hop FSO fixed-gain relaying
communication systems, and exact closed-form performance metrics are presented in
terms of the bivariate H-Fox function. This model is further enhanced through the
deployment of a multihop FSO relaying system as an efficient technique to mitigate
the turbulence-induced fading as well as pointing errors.
| Identifer | oai:union.ndltd.org:kaust.edu.sa/oai:repository.kaust.edu.sa:10754/621942 |
| Date | 11 1900 |
| Creators | Zedini, Emna |
| Contributors | Alouini, Mohamed-Slim, Computer, Electrical and Mathematical Science and Engineering (CEMSE) Division, Ooi, Boon S., Laleg-Kirati, Taous-Meriem, Karagionnidis, George K. |
| Source Sets | King Abdullah University of Science and Technology |
| Language | English |
| Detected Language | English |
| Type | Dissertation |
Page generated in 0.5974 seconds