PAPR Reduction Techniques For OFDM Systems

Orthogonal Frequency Division Multiplexing (OFDM) is an attractive technology for wireless communication. OFDM based systems are widely used for wireless applications because it provides high spectral efficiency, multipath delay spread tolerance, immunity to the impulse noise and frequency selective fading channels.Selected Mapping (SLM) is an efficient method for peak-to-average power ratio reduction in OFDM systems. In SLM technique the data sequence is multiplied with each phase sequences generated. And thus sequences which carry same information are formed. From these signals, the signal with minimum PAPR is selected for transmission. The major disadvantage of SLM technique is the need of transmission of Side Information bits to the receiver side for the recovery of the original data.