Discrete Cosine Transform-II for Reduction in Peak to Average Power Ratio of OFDM Signals Through μ-Law CompandingTechnique

摘要

Orthogonalfrequency Division multiplexing (OFDM) is the most familiar word intelecommunicationand wireless communication systems as it provides enhanced spectral efficiency than Frequency divisionmultiplexing (FDM).Although itissustaininganorthogonal relationbetweencarriers but highpeak toaverage power ratio (PAPR)is oneof the main disadvantages of OFDMsystem.Various PAPR reductiontechniques have beenused,including techniques based oncompanding. Incompanding,.-Lawcompandinghas potential toreducethePAPRof OFDMsignals..-Law Compandingtechniquepreserves thedynamic range of samples at low amplitudes.Anew methodnamed as precoding which ishaving less complexity compared to the other power reductiontechniquesis proposed to reduce PAPR.This paper put forward combinationof two existing techniques namely.-LawCompanding Transformand Discrete Cosine Transfo rm-IIprecoding technique.The simulationresults show that, the proposedcombinedscheme givesbetter result for PAPR Reductionand resultsin no distortion