Comparative Research Analysis on LTE Techniques to Reduce PAPR in Multi-Carrier Communication Systems

New technologies emerging day by day and main focus to give a better quality of service at low cost. LTE has adopted DFT-spread OFDMA technique as the uplink multiple access schemes which use single carrier modulation and frequency domain equalization. In our research work, we show the PAPR performance of DFT-spreading technique. The performance of PAPR of DFT spreading technique is dependent on the number of subcarriers assigned to each user. In this thesis, a method for PAPR reduction in LTE system has been introduced, which is based on the DFT spread method. DFT spread method is further classified into two methods known as LFDMA (localized FDMA) and IFDMA (interleaved FDMA). It was shown that an interleaved FDMA and localized FDMA perform better than orthogonal FDMA in the uplink transmission where transmitter power efficiency is of great importance in the uplink. LFDMA and IFDMA result in lower average power values due to the fact that OFDM and OFDMA map their input bits straight to frequency symbols where LFDMA and IFDMA map their input bits to time symbols. We conclude that single carrier-FDMA is a better choice on the uplink transmission for cellular systems. Our conclusion is based on the better efficiency due to low PAPR and on the lower sensitivity to frequency offset since SC-FDMA has a maximum of two adjacent users. From results, it can also be concluded that the performance of IFDMA is far better than the LFDMA.