Resource Allocation for Heterogeneous Services Per User in OFDM Distributed Antenna Systems

In this paper, we focus on the development of effective and practical scheduling algorithm for heterogeneous services per user of orthogonal frequency division multiplexing distributed antenna systems (OFDM-DAS). We take two scenarios into account: 1)Fixed distributed antenna connection (FDAC), in which each user can connect to only one distributed antenna (DA) port; 2)Dynamic DA connection (DDAC). In this scenario the power constraint of single DA port is considered and users can dynamically connect to the DA ports. Firstly, the optimization problem of heterogeneous services based on utility function is formulated and a algorithm namely joint dynamic subcarrier assignment and sharing (JDSAS) is proposed. Then, in FDAC scenario, a suboptimal algorithm namely FDAC-JDSAS is proposed. In DDAC scenario, a DDAC-JDSAS algorithm is evolved from FDAC-JDSAS by converting the power constraint to subcarrier constraint. The design goal is to fully exploit multiuser diversity gain and DA selection diversity gain while guaranteeing the quality of service (QoS) for delay sensitive services. Numeric results show that, in both FDAC and DDAC, our algorithms outperform traditional M-LWDF algorithm in terms of FTP throughput and fairness criterion.