Performance enhancement of DVB-RCT systems for interactive wireless broadcasting

Orthogonal frequency-division multiple access (OFDMA), which is a combination of orthogonal frequency division multiplexing (OFDM) with frequency-division multiple access (FDMA), is regarded as a promising solution for enhancing the performance of interactive broadcasting wireless systems. This paper presents our investigation for the impacts of symbol timing errors and peak-to-average power ratio (PAR) on OFDMA-based interactive broadcasting systems. Under the condition of the same side information bits, the selective mapping (SLM) approach can be implemented by decimating OFDM samples, which is less complex compared to the ordinary SLM incurring a slight degradation of the PAR performance. Including the effects of clipping operation and symbol timing misalignment, the bit error rate (BER) performance is investigated for a typical OFDMA uplink scenario.