Experimental validation of orthogonal frequency division multiplexing with peak-to-average power ratio reduction and out-band distortion control using software defined radio

Orthogonal frequency division multiplexing (OFDM) is an emerging technology in recent wireless communication standards where high data rate is required at low latency and better spectral efficiency. OFDM signals have a generic problem of high peak-to-average power ratio (PAPR) due to the superimposition of the data-modulated subcarriers. This high peak signals may result in amplifier non-linearity which creates many problems such as performance degradation and out-of-band distortion. Hence, the authors addressed this problem by designing and implementing four new PAPR reduction schemes such as phase modulation, rail clipping, sample and hold approach and threshold methods based on amplitude clipping to reduce PAPR and improve the band gap between spectral sidelobes to main lobe significantly. For practical proof of the suggested concepts, they have chosen software-defined radio as an experimental setup in which universal software radio peripheral N210 employed as hardware and GNU radio as software. Experimental results are analysed in terms of significant PAPR reduction and out-of-band spectral leakage control. Besides these, motivation, background and relevant mathematical analysis with rigid justification are presented in this study.