Peak to Average Power Ratio Reduction for Multi-band OFDM System using Tone Reservation

OFDM and its extension Multi-band OFDM (MB-OFDM) are considered as the modulation schemes for many future communications systems. But these schemes cause high PAPR which should be reduced before power amplification otherwise non-linearities can occur. In this paper Tone Reservation method is used for OFDM PAPR reduction where a corrective signal is added to the original signal to reduce its PAPR. The effect of some corrective signal properties which influence the PAPR reduction performance are discussed. It is revealed that corrective signal’s bandwidth and power are proportional to PAPR reduction gain while the bandwidth gap between useful and corrective carriers is inversely proportional to the PAPR reduction gain. Finally MB-OFDM PAPR reduction is performed and it is demonstrated that PAPR reduction performed with corrective tones optimization over all OFDM symbols is more efficient but computationally more complex at the same time. This MB-OFDM PAPR reduction method can also be generalized for PAPR reduction of a Software Radio signal.