Análise de desempenho do Algoritmo de Water-filling Modificado para Alocação de Recursos em Sistemas OFDMA

The growth of mobile communication systems with high data rate capacity and multiple users is pushing the researches about techniques that presents high spectrum efficiency. OFDMA is already a reality in many advanced mobile communication systems, such as LTE, IEEE802.16 and IEEE802.22. Nevertheless, the efficiency of the OFDMA technique depends on the resource allocation algorithm, which must consider the data rate and bit error rate (BER) required by each user and the channel frequency response to determine which subcarriers and the modulation orders shall be allocated for each user. The aim of this paper is to analyze the performance of a resource allocation algorithm, based on Water-filling theorem, but that has been modified to consider the required throughput of each user. The performance analysis includes the efficiency of the algorithm to fulfill the users requirements about throughput and robustness in a frequency-selective channels.