Carrier recovery and nonlinear compensation for DVB-S2 using multilevel pilots

The current DVB-S2 standard specifies the use of constant energy level pilots for receiver synchronization and equalization algorithms. However, these are unsuitable for APSK modulations due to the nonlinear response of the satellite power amplifier. In this paper, we investigate the performance of two low-complexity techniques for nonlinear compensation in DVB-S2 systems, i.e. static predistortion and cluster based sequence equalizer (CBSE). We also propose how multilevel pilot structures, matched to each technique, can be used for carrier recovery. Simulation results are presented in terms of total degradation wherein both techniques are shown to achieve a significant improvement over the conventional system.