A Hybrid Method Using Carrier Interferometry and Partial Transmit Scheme for PAPR Reduction

Communication is one of the important aspects of life. With the advancement in age and its growing demands, there has been rapid growth in the field of communications. Signals, which were initially sent in the analog domain, are being sent in the digital domain, even single–carrier waves are being replaced by multi– carriers. Multi–carrier systems like Carrier Division Multiple Access (CDMA) and Orthogonal Frequency Division Multiplexing (OFDM) are now–a–days being implemented commonly. In the OFDM system, orthogonally placed sub–carriers are used to carry the data from the transmitter end to the receiver end. Presence of guard band in this system deals with the problem of Inter Symbol Interference (ISI) and noise is minimized by larger number of sub–carriers. But the large Peak – to – Average Power Ratio (PAPR) of these signal have some undesirable effects on the system. In this paper we have focused on learning the basics of an OFDM system and have undertaken various methods to reduce the PAPR in the system so that this system can be used more commonly and effectively.