5. Conclusion
This paper introduced an SDN-based network management ar- chitecture and control mechanisms to provide resource elasticity in a TD-LTE system. Such a resource management flexibility intro- duced by this proposal can enhance the UL/DL diversity in a RAN deployment increasing performance gains, while providing a key enabler for the network operators to support a broad range of OTT application and cloud services with a wide variety of UL/DL traf- fic demands. The proposed mechanism can address flexibly UL and DL traffic requirements in an autonomous manner addressing ef- fectively pseudo-congestion by forming virtual cells enabling users to utilize resource from multiple eNBs allowing customized frames that resolve pseudo-congestion. An algorithm to manage the net- work resource providing flexibility and enhanced user performance has been introduced at the SDN controller to assess congestion situations and provide resolution via virtual cell provision and by enforcing TD-LTE frame re-configuration at selected eNBs. The re- sults obtained via system level simulations show significant im- provements in the average users performance including both edge users that reside within the virtual cell region and inner cell ones, without compromising the overall system performance. Further re- search is envisioned toward extending the proposed SDN based mechanisms considering split bearers and towards dynamic ad- justments in the mobile backhaul provisioning resources for lower layer transport mechanisms.
