Performance analysis of Piecewise linear Companding with various precoders for PAPR Reduction of OFDM Signals

1Professor,Dept.of ECE,GMR Institute of Technology,Rajam,AP,India 2Professor, Dept.of ECE ,GMR Institute of Technology,Rajam, AP,India 3Assistant Professor, Dept.of ECE ,GMR Institute of Technology,Rajam, AP,India ---------------------------------------------------------------------***--------------------------------------------------------------------Abstract Orthogonal Frequency Division Multiplexing (OFDM) is an attractive technique for wireless communication applications. However, an OFDM signal has a large Peak-toAverage Power Ratio (PAPR), which can result in significant distortion when passed through a nonlinear device, such as a transmitter power amplifier. Number of techniques has been proposed for reducing the PAPR in OFDM systems. Among them Companding is a well-known technique for the PAPR reduction of OFDM signals. Recently, a piecewise linear companding technique is proposed to extenuate companding distortion. There are different precoder systems to reduce PAPR without degradation Bit Error Rate (BER). In this paper we present Performance analysis of Discrete Hartley Transform (DHT) precoder with Piecewise linear companding OFDM system. We compare the computer simulation results of DHT precoded Piecewise linear companding OFDM system with Discrete Cosine Transform (DCT) precoder, Walsh Hadamard Transform (WHT) precoder, conventional Piecewise Linear Companding (PLC) OFDM system. Simulation results show that the PAPR of DHT precoded Piecewise linear companding OFDM system is lower than WHT precoded PLC OFDM system, DCT precoded PLC OFDM system and conventional PLC OFDM while maintaining good performance in the Bit Error Rate (BER) and Power Spectral Density (PSD).