Quality of Service performance of the Best-M OFDMA feedback strategy

Quality of Service (QoS) is an important performance indicator for any technique intended for its inclusion in commercial systems, as the provided service must fulfil the customers minimum demands. Several indicators for QoS are available in the literature, where the Symbol Error Rate (SER) outstands as one of the most important ones due to its large relations to correct symbols detection as well as to the achieved throughput. The Best-M feedback scheme has been proposed as an interesting technique for its use in Orthogonal Frequency Division Multiple Access (OFDMA) systems, mainly because of its data rate and feedback performance. This paper will study its QoS performance providing the SER closed form expressions to indicate the effect of the number of users, the operating SNR and/or the available number of feedback bits on the offered QoS. The performance of the proposed scheme is also presented via computer simulations where interesting conclusions are obtained.