Coordinated tethering for devices with multi-RAT capabilities: An algorithmic solution and performance analysis

Abstract One challenging requirement of the Internet of Things (IoTs) is related to the capability of the wireless access network to be able to provide internet connectivity to a very large number of devices, compared to conventional cellular use cases. With the WiFi technology being the spearhead of the wireless local area networks (WLANs), the exploitation of already deployed WLANs has gained ground as a practical and efficient approach towards increasing the spectral efficiency of wireless networks. Based on the coordinated tethering concept, we introduce a purely wireless heterogeneous network deployment, where cellular and WLAN radio resources are optimally coordinated towards the universal maximization of the user’s throughput. The wireless users (smartphones, IoT devices, etc.) are coordinated by the evolved node B (eNB) about their role in the network (access point (AP) or normal user) and the access technology they have to employ. The performance of the new approach has been investigated based on a theoretical framework that has been developed. In this context, closed-form expressions are derived for important statistical characteristics of the system’s output signal-to-interference plus noise ratio (SINR) for the single-user case with multiple interferers. Then, this approach is extended to a multi-user multi-cellular system and a greedy algorithm is proposed for optimizing the system performance. Various numerical and simulation results have presented, which show that the proposed multi-cellular multi-radio access technology (RAT) scheme with coordinated tethering may increase spectral efficiency.