As discussed in Chapter 2, up to now, only the DFT is used to implement the SC-FDMA system. However, it is possible to use other sinusoidal transforms such as the DCT, which is the main objective of this chapter. The DCT-SC-FDMA system is not studied in the literature. Recently, the DCT-OFDM system has received much attention, because it offers certain advantages over the DFT-OFDM system [45-47]. The main advantage of the DCT lies in its excellent spectral energy compaction property, which makes most of the samples transmitted close to zero leading to a reduction in the effect of ISI. In addition, it uses only real arithmetic rather than the complex arithmetic used in the DFT. This reduces the signal processing complexity, especially for real modulation signaling, where the DFT processing still uses complex arithmetic and suffers from I/Q imbalance problem [46,47].