Topic:Resource Allocation Mechanism For Energy Efficiency And Coverage Enhancement In NB-IoT Networks

As an emerging Low Power Wide Area Network(LPWAN),Narrow-band Internet of Things(NB-IoT)technology has been widely used in various IoT scenarios to meet the communication needs of IoT devices.However,as IoT devices enter various industries,massive devices need to access the cellular network for data communication,posing challenges to the limited energy and high frequency utilization of the network.In addition,because a large number of IoT devices are deployed in places with poor communication environments,higher requirements are imposed on the coverage capabilities of NB-IoT.Based on this problem,this paper have proposed an energy-efficient joint resource allocation and power control for cluster-based NB-IoT method,which enhances the energy efficiency of the system and improves the access rate of the device.At the same time,for the scenario where the NB-IoT coverage is insufficient,a Device-to-Device(D2D)cluster communication is introduced,and a NB-IoT network coverage enhancement mechanism based on D2D cluster communication is proposed to improve the overall edge rate of the system and enhance the coverage of the system.The specific introduction is as follows.1)Research for energy-efficient joint resource allocation and power control for cluster-based NB-IoT method.Firstly,this paper adopts an algorithm based on high-density clustering center for fast clustering to cluster devices into clusters and reuse the limited spectrum resources through the device terminal multiplexing channel.Secondly,due to the sensitive energy consumption of IoT devices,this paper proposes cluster head selection mechanism based on the optimal power remaining strategy in clustering.Thirdly,for the clustered NB-IoT network,this paper proposes a system energy efficiency optimal model,and then uses non-cooperative game theory to consider all feasible channel reuse schemes between clustered devices and non-clustered devices.And the optimal transmit power of the NB-IoT device is obtained by solving the Nash equilibrium point.Finally,a perfect match is obtained from these feasible channel assignments by using the Hungarian method.2)Research on NB-IoT Network Coverage Enhancement Mechanism Based on D2D Cluster Communication.Firstly,this paper proposes a D2D clustering algorithm based on the Hungarian algorithm,and obtains the D2D clustering scheme with the lowest system outage probability.Secondly,this paper proposes a system optimization model with the largest edge rate in the case of mutual multiplexing of channel resources between cellular devices and D2D devices.Finally,the paper decomposes the model into two sub-problems:power control and channel assignment sub-problems.For the first sub-problem,this paper uses game theory to find the optimal transmit power of all devices under the condition of maximizing system edge rate.Then,the Hungarian algorithm is used to obtain the optimal channel allocation strategy for the second subproblem.In short,this paper addresses the energy consumption and coverage requirements of massive IoT devices accessing NB-IoT networks,this paper have proposed an energy-efficient joint resource allocation and power control for cluster-based NB-IoT method to save the energy and an mechanism based on D2D group communication to enhance the coverage ability of the NB-IoT system respectively,which can ensure the connectivity of massive IoT.