Power Saving Scheduling Scheme for Internet of Things over LTE/LTE-Advanced Networks

Yen-Wei Kuo,Li-Der Chou

doi:10.1155/2015/971538

Abstract

The devices of Internet of Things (IoT) will grow rapidly in the near future, and the power consumption and radio spectrum management will become the most critical issues in the IoT networks. Long Term Evolution (LTE) technology will become a promising technology used in IoT networks due to its flat architecture, all-IP network, and greater spectrum efficiency. The 3rd Generation Partnership Project (3GPP) specified the Discontinuous Reception (DRX) to reduce device’s power consumption. However, the DRX may pose unexpected communication delay due to missing Physical Downlink Control Channel (PDCCH) information in sleep mode. Recent studies mainly focus on optimizing DRX parameters to manage the tradeoff between the energy consumption and communication latency. In this paper, we proposed a fuzzy-based power saving scheduling scheme for IoT over the LTE/LTE-Advanced networks to deal with the issues of the radio resource management and power consumption from the scheduling and resource allocation perspective. The proposed scheme considers not only individual IoT device’s real-time requirement but also the overall network performance. The simulation results show that our proposed scheme can meet the requirements of the DRX cycle and scheduling latency and can save about half of energy consumption for IoT devices compared to conventional approaches.

Highlights

The concept of Internet of Things (IoT) enables devices to connect to the Internet to sense data and interact with each other
It can be predicted that IoT devices referred to as IoT User Equipment (UE) pieces will grow rapidly and the power consumption and radio spectrum management will become the critical issues in the IoT networks
In our previous study [17], we proposed an effective Adaptive Smart Power Control Algorithm (ASPCA), which can be applied to cluster IoT UEs in the coverage hole and to deal with the cross-tier interference issues by determining an appropriate serving range of home Evolved Node B (eNodeB)

Summary

Introduction

The concept of Internet of Things (IoT) enables devices to connect to the Internet to sense data and interact with each other. In the LTE network, the 3rd Generation Partnership Project (3GPP) specified the Discontinuous Reception/Transmission (DRX/DTX) mechanism to alleviate the power consumption issue which can severely affect the battery lifetime of the IoT UEs. The DRX mechanism allows UEs to stop monitoring the Physical Downlink Control Channel (PDCCH) and to enter low-power consumption mode to extend its battery lifetime. Without DRX mechanism, the LTE UEs have to continuously monitor the PDCCH in every subframe in order to check UE-specific scheduling assignments such as Downlink (DL) resource allocation, Uplink (UL) grants, and PRACH (Physical Random Access Channel) responses. The UEs and the Evolved Node B (eNodeB) can benefit from the DRX mechanism to reduce its power and signal consumptions, such as the Channel State Information (CSI) or Sounding Reference Signal (SRS), and to improve its resource utilization. Different from the single DRX cycle in the Universal Mobile Telecommunications System (UMTS), the LTE network introduces two types of DRX cycles, the short and long DRX cycles, which complicates the DRX parameters configuration

Objectives

Results

Conclusion