Downlink Resource Allocation with Cooperative Transmission in EPON-WiMAX Integrated Network

The rapid growth of the demand of multimedia applications in recent years has posted a much higher bandwidth demand than before. As a result, the technology of broadband access is becoming more and more important. Integrating Ethernet Passive Optical Network (EPON) and Worldwide Interoperability for Microwave Access (WiMAX) has been considered as a very promising solution for broadband access. Although EPON-WiMAX has received many attentions in research, yet most of the previous researches focus on the uplink packet scheduling and bandwidth allocation. Thus, in our research, we focus on the downlink scheduling and resource allocation problem. In particular, we focus on utilizing the cooperative transmission technique. Based on the advantage of EPON-WiMAX architecture, the resource allocation problem utilizing cooperative transmission can be done at the optical line terminal (OLT) in a centralized manner. We first formulate the problem as a linear programming (LP) problem. Due to the high complexity of LP, we propose a heuristic algorithm to solve the problem. Our simulation results show that the proposed algorithm is able to increase the system throughput while guaranteeing the QoS of different classes of traffic.