Peak Power Reduction Using Improved Selective Mapping Technique for OFDM

The concept of Orthogonal Frequency Division Multiplexing (OFDM) was initiated and well prominent since 1966 and gradually reached to its development into standard system form during 1990. Large amounts of digital data, with high data rate, reliable communication over fading channels can be transmit over radio waves that is why OFDM is known to be an attractive technique for multicarrier transmission scheme, it is an attractive technique for fourth generation wireless communication. The term OFDM is a special type of FDM which has very vast application in the field of wireless and wired communication systems. OFDM has Major disadvantage is that it leads to high Peak to Average Power Ratio (PAPR) which is consider to be as the main implementation drawback. This kind of system has the possibility of high PAPR. In this paper we are discussing about PAPR which affects the performance and efficiency of Power Amplifier (PA) and its influence by utilizing the Selective Mapping (SLM) technique in OFDM system for reduction of PAPR. Many kinds of techniques are available in OFDM system for reduction of PAPR, However the idea for improved SLM produces several independent signals based on converting the original data lock into many independent signal and then the signal has lowest PAPR that specific signal is transmitted. Also data rate trade-off exist at the receiver end when side information is detected for the recovery of data block which leads to the reduction of data rate. Improved SLM techniques for reducing the PAPR is the most promising reduction technique in its non-uniform phase factor for PAPR reduction in multicarrier OFDM system. Furthermore the estimate expression by using Complementary Cumulative Distribution Function (CCDF) for PAPR has been discussed. Simulated results demonstrate that OFDMA signals using improved SLM technique carried significant effects in reduction of PAPR in OFDM system.