Resource allocation in OFDMA based broadband wireless access systems

One of the main issues involved in the development of the 4G wireless systems is the choice of Multiple Access (MA) technique. Unlike the existing 2nd Generation (2G) and 3G systems which are low speed and mainly aimed at voice communications, the 4G systems are designed to provide much higher data rate and to support IP-based data services.;The primary goal of a wireless communications system is the fulfillment of quality of service (QoS) requirements of users. Quality of Service requirement is defined by achieving the data transmission rate and bit error rate of each user in each transmission. Radio resource allocation plays a key role in optimizing the performance of an OFDMA system.;Orthogonal Frequency Division Multiple Access (OFDMA) base-stations allow multiple users to transmit simultaneously on different subcarriers. This paper implements two algorithms: (1) Linear Method, and (2) Non Linear Method, to allocate subcarriers and power to the users that are sharing the channel.;The performance of each of the methods is analyzed. Simulation results indicate that the linear method yields better performance results and has significantly lower complexity when compared to the non linear method.