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This article first appeared in the Railway-News magazine, Issue 4 2022 Data & Monitoring edition.Climate change commitments by the global transport sector are driving initiatives to increase passenger occupancy on the rail network, while simultaneously growing the freight rail business.This focus on providing relief to road and other transport systems comes with an increased pressure on keeping the rail network running smoothly, efficiently and safely with very little downtime.Access to real-time operational information is at the heart of delivering on this promise. It is critical to know what happens, and where, throughout the network: from tracking trains on route, to locating and addressing issues along the track, to keeping operators updated with safety information. Therefore, a resilient and reliable communications infrastructure is needed to help keep the rail industry moving.But how do you find a system that will be up and running quickly and easily, within budget and with minimum disruption to operations? Together with its network of specialist system partners, DAMM Cellular Systems has cooperated successfully with a series of worldwide rail and metro operations to deliver high- performance voice and digital communications that do just that.
To predict AAL2 multiplexing performance, we derived bandwidth gain analytically using discrete Markov chain model for voice service and validated these results with a simulation. And we also performed detailed simulation for voice and data services in a concentrator. Based on the analysis, we find that there is no major benefit of AAL2 multiplexing in a concentrator. The benefit of AAL2 multiplexing in Iub for data services is much less than that for voice service. The results also indicate that end-to-end application-level performance must be incorporated in all development phases and the benefit of AAL2 multiplexing depends heavily on the traffic load. 2b1af7f3a8