Enhancing User QoE in Multi-Carrier LTE Dense Networks via Multi-Path Support

Small cells are low cost solutions that address effectively the growing traffic demands, enhancing the capacity of Radio Access Networks (RANs) at particular locations. In this paper, we combine the attributes of carrier aggregation with multi-path transport considering a cell-less architecture introduced by virtual evolved NodeBs (eNBs) as established in the iJoin project. A virtual eNB is formed by a cloud unit referred to as RAN as a Service (RANaaS) and a set of small cells. The RANaaS can flexibly centralize and handle selected RAN functionalities depending on the backhaul characteristics and/or other network optimization targets, e.g. load balancing. By coupling selected carriers and paths in a multi-connectivity environment, RAN and backhaul resources may be jointly allocated to users based on Quality of Service (QoS) requirements, considering channel conditions, backhaul load and the application type. In exploiting path diversity with increased inter-path control and coordination, this paper introduces a combined carrier/transport proxy function, located on the RANaaS in order to shorten the multi-path distance. Such a proxy function consists of a classifier, which categorizes carriers based-on QoS, and a state prediction process that influences the eNB scheduler to allocate carriers considering network resources across the RAN and backhaul. In the absence of a multi-path proxy, a direct end host based seeding token mechanism is also analyzed considering the impact and requirements on the RAN.