On convergence and coexistence of LTE and Wi-Fi networks

Abstract

The proliferation and penetration of smart phones and IoT devices is having profound impact on world economy. In order to support billions of wirelessly connected devices, and tackle exponentially increasing traffic demands and ever-increasing Quality of Experience and energy efficiency requirements of diverse services and applications being carried over communication network infrastructure, convergence and coexistence of various radio access technologies (RATs) is required. In this work, we present various architectures and traffic steering mechanisms for efficient interworking of LTE and Wi-Fi networks and evaluate their performance for carrying TCP traffic which is sensitive to out-of-order delivery of packets at the receiver. Unlike interworking which requires simultaneous usage of both LTE and Wi-Fi radios at user equipment (UE), mobile operators are considering deployment of LTE-U/LAA in unlicensed bands so that only one radio is used at UE. However, to use unlicensed bands LTE-U/LAA needs to fairly co-exist with Wi-Fi. To address this inter-RAT hidden terminal problem, we present novel solutions that either rely on a central inter-RAT controller or work without any such controller in a distributed manner.