COMBINED INTERLEAVING AND COMPANDING FOR PAPR REDUCTION IN OFDM SYSTEMS

Peak to Average Power Ratio (PAPR) is one of the serious problems in any wireless communication systems using multicarrier modulation technique as OFDM, which reduces the efficiency of transmit high power amplifier. In this paper, proposed scheme will be introduced, which combines interleaving technique and companding technique to reduce PAPR. This scheme will be compared with the system that uses other technique for reduction which is the clipping technique. By using proposed scheme, the PAPRof OFDM signal can be reduced by 6.8 dB over the original system, i.e., without PAPR reduction. Also, SNRdecreases by more than 5 dB for Bit Error Rate (BER) of 10−3 over the original system. Moreover, the proposed scheme gives improvement more than 4.5 dB for BERof 10 −3 over the system that uses clipping. All these systems will be evaluated in the presence of nonlinear power amplifier.