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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. |