Author : Alaa Deshar Farhood, Neelesh Agarwal,A.K. Jaiswal, Navendu Nitin and Maham Kamil Naji

The LTE employs OFDMA for downlink data transmission because Orthogonal Frequency Division Multiple Access (OFDMA) scheme offers high spectral efficiency and better resistance to fading environments. In OFDMA the data is modulated using multiple number of sub-carriers that are orthogonal to each other because of which the problems associated with other modulation schemes such as Inter Symbol Interference (ISI) and Inter Carrier Interference (ICI) are reduced .In this paper the performance of OFDMA system in LTE is taken into account, Then, the main technologies are explained, together with possible improvements, their associated challenges, and some approaches have been considered .We also investigate the performance of OFDMA in LTE physical layer by considering different modulation schemes (BPSK, QPSK, 16QAM and 64QAM) on the basis of PAPR, BER, power spectral density (PSD) and error probability .

Keywords: OFDMA, LTE, BER, PAPR, PSD, BPSK, QPSK, 16QAM and 64 QAM

Article published in International Journal of Current  Engineering  and Technology, Vol.4,No.3 (June- 2014)