Performance analysis and simulations of OFDMA based BWA

For improving transmission quality of physics channel in NLOS BWA operation environment and solving multi-path and frequency selectivity attenuation in city wireless complex channel environment,the OFDM-based OFDMA BWA and OFDMA modulation specialty are discussed in this paper,and the exterior environment,capacity and problems of BWA and the service strategy for improving quality of NLOS BWA are analyzed also. IEEE 802.16 supports two OFDM systems,one is OFDM,and another is OFDMA. In this paper,we introduce and analyze the performance of OFDMA system,and theoretic analysis and computer simulations are used to assess the performance of NLOS BWA operation environment.