A Segment-Based Adaptive Joint Session Scheduling Mechanism in Heterogeneous Wireless Networks

Joint session scheduling (JOSCH) enables traffic to be split and transmitted over multiple radio access networks (RANs) simultaneously, which improves the quality-of-service (QoS) in terms of transmission rate, reliability and stability. Transmission synchronization is one of the key issues which JOSCH should consider, as it has direct effect on the performance of buffer management and data reassembly at the traffic receiver. In this paper, a segment-based adaptive JOSCH mechanism was proposed to guarantee the transmission synchronization during multi-RANs simultaneous transmission. The proposed mechanism restrains the delay differences between different RANs, by adjusting the traffic allocation ratios to multiple transmission RANs adaptively, based on the feedback from traffic receiver. System architecture and functional modules are designed to support the proposed mechanism. Meanwhile, a generic transport protocol model supporting multi-RANs transmission is introduced as well. Simulation results reveal that the proposed JOSCH mechanism well adapts to the dynamic change of network conditions, and guarantees the synchronization and stability of transmission.