Cascaded Scheduling Scheme for Massive Multi-Connectivity

Industrial applications pose strict requirements on latency and reliability performance of communication systems. Not all of these requirements can be met by current wireless communication standards. A promising solution to enhance latency and reliability performance of wireless communication systems is Multi-Connectivity (MC), i.e., using multiple communication paths at once. Previous work has identified and evaluated variations of three basic MC scheduling schemes, namely packet duplication (PD), load balancing (LB) and packet splitting (PS). In this work a cascaded MC scheduling scheme is proposed that combines multiple of these basic scheduling schemes in the presence of multiple available links, i.e., in massive MC scenarios. Equations are derived describing latency and reliability performance of PS, PD, LB and the cascaded MC scheme for scenarios with uncorrelated and fully correlated links. The MC schemes are evaluated with the single link performance modelled by ns-3 simulations for IEEE 802.11ac in an industrial scenario. The evaluation reveals that the cascaded MC scheduling scheme can provide significant gains for MC latency and reliability performance in several scenarios and shows that it is a promising candidate to realize demanding industrial applications.