Traffic Splitting for End-to-End Delay Jitter Control in Uplink Multi-Access Systems

We share our approach to design and implementation of a working uplink multi-access system that caters to the use-case of a mobile smart ambulance. While attempting delivery of Ultra High Definition video from this system to a backend facility, we identified the need for mechanisms using which the end-to-end delay jitter variation across the different interfaces are controlled via intelligent traffic splitting schemes. The traffic splitting approach to achieve the target jitter performance requires an in-depth understanding of jitter performance under the control of LTE's uplink synchronous Hybrid Automatic Repeat Request (HARQ). We provide an analysis of end-to-end delay jitter under LTE's synchronous HARQ in uplink and use the structural results so obtained to design a traffic split mechanism. We validate our analysis, and provide traffic split performance results from our working multi-access system that uses multiple LTE modems from several operators to deliver streaming traffic to a central server.