الفهرس 
Single and Multi-Carrier Communication SystemsOnly 14 pages are availabe for public view
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Abstract
The Single-Carrier Frequency Division Multiple Access (SC-FDMA) system is a wellknown
system, which has recently become a preferred choice for uplink channels. This is
attributed to its advantages such as the low Peak-to-Average Power Ratio (PAPR), and the
use of frequency domain equalizers. Moreover, it has a similar throughput performance and
essentially the same overall complexity as the Orthogonal Frequency Division Multiple
Access (OFDMA) system. However, the presence of Carrier Frequency Offsets (CFOs)
between the transmitter and the receiver results in a loss of orthogonality among subcarriers
and an Inter-Carrier Interference (ICI). CFOs also introduce Multiple Access Interference
(MAI) and degrade the Bit Error Rate (BER) performance in the SC-FDMA system.
Moreover, the performance degradation due to the nonlinear amplification may substantially
affect the link performance of the system. As a result, there is a need to enhance the
performance of the SC-FDMA system, which is the main objective of this thesis.
The thesis presents an improved Discrete Cosine Transform (DCT)-based SC-FDMA
system. Simulation results show that the DCT-based SC-FDMA system provides better BER
performance than the DFT-based SC-FDMA and OFDMA systems, while the complexity of
the receiver is slightly increased. Moreover, it was concluded that the PAPR of the DCTbased
SC-FDMA system is lower than that of the OFDMA system
In addition, a new transceiver scheme for the SC-FDMA system is introduced and
studied. Simulation results illustrate that the proposed transceiver scheme provides better
performance than the conventional schemes and it is robust to the channel estimation errors.
The problem of CFOs is investigated and treated for the Single-Input Single-Output
(SISO) and the Multiple-Input Multiple-Output (MIMO) SC-FDMA system. New lowcomplexity
equalization schemes, which jointly perform the equalization and CFOs
compensation have been presented and studied. The mathematical expressions of these
equalizers have been derived taking into account the MAI and the noise. Low-complexity
implementations of the proposed equalization schemes using a banded matrix approximation
have been presented in the thesis. from the obtained simulation results, the proposed
equalization schemes have proved to be able to enhance the performance of the SC-FDMA
system, even in the presence of estimation errors.