الفهرس 
Resource Allocation for NOMA SystemOnly 14 pages are availabe for public view
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Abstract
Non-orthogonal Multiple Access (NOMA) as one of the upcoming and promising multiple
access technologies has a significant impact on the development of the Fifth Generation (5G)
wireless communication systems. A popular NOMA scheme uses a power domain-NOMA
(PD-NOMA) to achieve multiple access, in which multiple users are allocated distinct power
levels according to their channel state while allowing the same time, frequency, and code
resources at the transmitter sides. The resource allocation represented in power allocation (PA)
and user pairing (UP) or subcarrier-user assignment (SUA) are the two interacted factors for
achieving high performance of the NOMA system.
Therefore, firstly, the thesis proposes a subcarrier-user allocation algorithm for the
downlink NOMA system to enhance the spectral efficiency of the system and the successive
interference cancelation performance by guaranteeing a high difference in channel-gain
between the paired users per subcarrier compared to the conventional UP algorithms.
Secondly, the thesis presents two proposed subcarrier-user assignment algorithms
(SUAAs) for the downlink NOMA system to enhance the spectral efficiency, the user fairness,
the data rate of weak users, and the outage probability compared to the existing algorithms.
The assignment order of the 1st proposed SUAA is based on the worst subcarrier first (WSF)
to avoid selecting a user with the worst channel gain with any subcarrier and named (WSFSUAA). On the other hand, the 2nd proposed SUAA is based on spectral efficiency
maximization (SEM) and named (SEM-SUAA), but requires exhaustive search.
Finally, the thesis proposes a PA algorithm named the weighted energy efficiency power
allocation (WEE-PA) algorithm to maximize the total weighted energy efficiency (WEE) and
also to improve user fairness, minimum user rate of the system, outage probability, and average
data rate per weak user compared to the existing PA schemes.