Effects of Spectral Shaping on OFDM Transmission Performance in Nonlinear Channels

This paper proposes a spectral shaping method for OFDM signals that reduces nonlinear distortion. In this method, new subcarriers, which are produced from original subcarriers, are inserted into a conventional OFDM signal to smooth the spectral shape. The results of computer simulations in a nonlinear channel show that spectral-shaped OFDM signals have lower out-of-band spectrum properties and bit-error rate than conventional OFDM signals when an iterative clipping-and-filtering technique is used in the transmitter.