A novel method for joint PAPR reduction and sidelobe suppression in NC-OFDM based Cognitive Radio system

摘要

The high peak to average power ratio (PAPR) and large spectrum sidelobe power are the two major limitations at the transmitter side of the NC-OFDM based Cognitive Radio (CR) system, which may significantly reduce the power efficiency and performance of the system. There are many techniques in the literature to reduce high PAPR and large spectrum sidelobe power. In this paper, we present a new optimization method for the reduction of both PAPR and sidelobe power jointly. It aims at the joint utilization of extending the outer constellation points and adding pre-determined tones on to the subcarriers. Since the convex optimization is computationally complex in nature, a suboptimal method is also proposed whose simulation result shows that there is a significant improvement in terms of PAPR and sidelobe reduction.