A novel access scheme for IoT communications in LTE-Advanced network

Long Term Evolution-Advanced (LTE-A) is increasingly seen as a promising technology for serving Internet of Things (IoT) needs along with mobile user equipments (UEs), due to high data rate, low latency, priority services, etc. The major challenges of incorporating IoT devices into LTE-A are, a large number of IoT devices attempting to access the network in short time, their effect on existing UEs communication, and the need for extra bandwidth to accommodate them. In this paper, we propose a novel framework and scheduling algorithm that uses heterogeneous network architecture (macro eNodeB and mini base stations) to reduce the collision rate and access delay of dense IoT devices by randomizing their access without affecting the Quality of Service (QoS) offered to UEs. Furthermore, the proposed idea avoids the use of extra spectrum or barring mechanisms for IoT devices. Simulation results for a heterogeneous network within a single macro cell with 1 macro eNodeB and 4 mini base stations (mini cells) indicate that the proposed framework and scheduling reduces the collision rate for IoT devices by 80% and access delay by more than 50% during the LTE Random Access Channel (RACH) procedure, as well as improves the QoS to UEs as compared to the Access Barring scheme.