BER Analysis of SDMA-OFDM Systems in the Presence of Power Amplifier Nonlinearities

The extension of OFDM to multiuser structures like space division multiple access (SDMA) helps to increase the spectral efficiency and system capacity. However, power amplifier nonlinearities reduce severely the performance due to the high peak to average power ratio (PAPR) that is a typical characteristic of multicarrier systems. This paper derives a theoretical upper bound on the bit error rate performance of a SDMA-OFDM system subject to power amplifier nonlinearities. Simulations show good agreement with theoretical results. The BER performance as a function of power amplifier efficiency is also studied