Uplink Modulation Strategies in 4G Wireless Cellular Systems
New upcoming wireless communication standards utilizing Ortogonal Frequency Division Multipexing (OFDM) provide high data rates and good signal cell coverage that makes their application extremely promising in fourthcoming years. Despite of its widely recognized benefits, sensitivity to the nonlinear amplification remains still a special issue to be solved. Recent solution to overcome this problem has been introduced by 3GPP consortion in Release 8, where the particular precoded OFDMA scheme, a closely related OFDMA alternative, is considered. This approach is widely recognized as a Single Carrier Frequency Division Multiplexing (SC-FDMA) and is characterized by using Discrete Fourier Transformation (DFT) for the signal spreading/despreading purposes.