Comparison of Single- and Multi-carrier Block Transmissions under the Effect of Nonlinear HPA

The influence of nonlinear high power amplifier (HPA) at transmit side on single-and multi-carrier block transmission systems is studied in wireless mutipath environments. We consider the single carrier block transmission with frequency domain equalization (SC-FDE), OFDM and MC-CDMA. The effective signal-to-noise ratio (SNR) and SNR penalty caused by the nonlinearity are derived and analyzed. In addition, bit-error rate performance is simulated and compared for various constellations in different channel conditions. The results show that SC-FDE is a robust solution to the nonlinear effect appeared at transmitter side, compared with OFDM and MC-CDMA. MC-CDMA only achieves similar performance as SC-FDE in case of sufficiently high input power backoff, especially for lower constellations. Moreover, the SNR penalty obtained from simulations for SC-FDE and MC-CDMA has a good agreement with that analytically predicted.