الفهرس 
MotivationOnly 14 pages are availabe for public view
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Abstract
The explosive growth in mobile trac demanded more requirements such as;
high-speed, high capacity, real-time data, and high-reliability. It is widely
accepted that, compared to 4G network, 5G network is expected to achieve
1000 times higher in system capacity, 10 times the spectral eciency, energy
eciency and 25 times the average cell throughput. As a result, the di erence
between capacity requirements and spectrum lack becomes more obvious. For
this reason, it is necessary to change the current transport network technology
of wireless communications systems.
Nowadays, new innovation approach called -centralized radio access network
(Cloud-RAN or C-RAN)- architecture is developed to meet the explosive
growth in mobile trac in 5G mobile networks, especially in the need of
high-speed, high capacity, real-time data, and high-reliability. In C-RAN ar-
chitecture, fronthaul networks provide connectivities between Remote Radio
Heads (RRHs) and Base Band Processing Unit (BBU). An important require-
ment in 5G fronthaul networks is to be able to forward massive trac to/from
a large number of devices connected to RRHs into the BBU pool. Actually,
the ber optics technology succeeded in matching all expectations for increas-
ing capacity and trac, as it can provide links with the high-speed data rate,
low-latency, reliability, and high security. However, optical ber is not de-
ployed in several regions, or there is insucient ber optics infrastructure.
Therefore, it is necessary to use other wireless communications technologies
such as: Free Space Optics (FSO) and Millimeter Wave (mmW) that are suit-
able to replace ber optics.
In this thesis, the problem of enhancing 5G fronthaul network performance,
while sustaining the cost of the network in terms of number of FSO and mmW
transceivers is addressed. In the rst part of this thesis, we aim at enhancing
the performance of redirected cooperative hybrid FSO/mmW 5G fronthaul
networks in C-RAN architecture and compare the results with recent exist-
ing topologies. Towards that, two proposed resource allocation schemes are
presented as suggested approaches to improve the performance of redirected
cooperative hybrid FSO/mmW 5G fronthaul networks. Several objectives
such as: network reliability, average transmitted power, and average bit er-
ror rate (BER) are considered in our analysis. The schemes are formulated
as multi-objective optimization problems (MOOP) and solved by exhaustive
search method (ES). The results reveal that the proposed schemes enhance
the network performance more than traditional networks, especially at severe
weather conditions.
In the second part of this thesis, optimal FSO and mmW transceivers place-
ment schemes are proposed in order to obtain the strategic locations of FSO
and mmW transceivers on RRHs. Towards that, two joint transceiver place-
ment and resource allocation schemes are proposed as suggested approaches
to improve the performance of redirected cooperative hybrid FSO/mmW 5G
fronthaul networks. Several objectives such as: network reliability, average
transmitted power, average bit error rate (BER) and number of distrupted
links are considered in our analysis. The schemes are formulated as multi-
objective optimization problems (MOOP) and solved by exhaustive search
method (ES). The results reveal that the proposed schemes help in further
enhancement for the resource allocation schemes proposed in the rst part and
determine the required number of transceivers at each RRH for the desired
performance.