Throughput maximization using adaptive modulation in wireless networks with fairness constraint

In multi-access wireless communication networks, cochannel interference and timing varying nature of the channel are two important detrimental effects to reduce the network throughput. Adaptive modulation techniques have the potential to substantially increase the spectrum efficiency by providing the users with different levels of throughput according to the channel conditions. In this paper, we study how to adaptively allocate each user´s throughput in the multi-access networks. We optimize the network throughput, while each user´s time average throughput is kept as a constant to ensure fairness. We solve the problem in two steps. First, we find the throughputs range that each user can select at different time to ensure the fairness. Second, we find the best throughput allocation to different users at each time to generate the maximum overall throughput. From the simulation results, it shows that our scheme increases overall network throughput about 10%, compared with the previous works.