Two-Stage Companding Scheme to Reduce Peak-to-Average Power Ratio for Safety Transportation Scenarios

Reliable wireless data transmission in intelligent transportation systems (ITS) has drawn a wide concern in recent years. As an efficient wireless transmission technology, multi-carrier communication (MCM) finds its way in many applications. However, the high peak-to-average power ratio (PAPR) of the MCM signal degrades the system performance. To remedy this, this paper introduces a novel two-stage distribution-based companding technique for the PAPR reduction of MCM transmission in transportation. The main principle of this technique is to transform the original MCM signal distribution into a desirable two-stage distribution, that is, compressing the large signals while maintaining the small signals constantly. In addition, a new variable parameter is also proposed to give the system more design flexibility. The simulation evaluation demonstrates the validity of the proposed companding technique.