Energy efficiency analysis of narrowband Internet of Things with auxiliary active cycles for small data transmission

Abstract

Narrowband Internet of Things (NB-IoT) is a cellular-based technology standardized by the Third Generation Partnership Project (3GPP) in Release-13 with the primary focus to support low-power, low-data rate, and delay-tolerant applications. The main contributions of this article are: (a) we describe the architecture of NB-IoT and its evolution in further 3GPP Releases and (b) we develop a semi-Markov based energy-saving model for the NB-IoT device. Different from the other existing approaches which focus on the optimization of power consumption of the NB-IoT device, we propose the addition of a novel Auxiliary State to the conventional NB-IoT Discontinuous Reception (DRX) mechanism. This state facilitates the reduction in energy consumption of the NB-IoT device, especially in case of small data transmission. The performance of the proposed scheme is analyzed in terms of power saving factor and average delay experienced by the device for varying eDRX timer, PSM timer, DRX cycle duration, and DRX active duration values. The proposed model is also evaluated for different arrival rates of the data packets and thresholds on the number of data packets.In this study, we claim that the newly introduced Auxiliary State improves the power saving of the NB-IoT user on the arrival of very small data packets. Numerical results show that the power saving factor increases up to 97.1% and 98.25% by varying the eDRX timer and PSM timer, respectively.

Energy Efficiency and Latency Optimization for IoT URLLC and mMTC Use Cases

“…However, energy consumption was investigated without considering the impact of various resource unit configurations (RUCs) and resource allocation on the transmission process. In [13], a semi-Markov model of radio resource control (RRC) connected and idle states (particularly the discontinuous reception and the power saving mode) was proposed to finalize energy savings. Similarly, the authors of [14] analyzed the NB-IoT downlink power consumption model and used the particle swarm algorithm for energy consumption optimization.…”

Power efficient stochastic modeling for Narrowband Internet of Things devices in 5G networks

“…In eDRX mode, UE sleeps with disabled Radio Resource Control (RRC) connection and receives regular paging messages from the core network. 4 Although, UE is not reachable in PSM mode, but it is still registered to the core network. The presence of eDRX mode and PSM mode in RRC idle mode contributes to the battery saving of UE.…”

“…To further enhance UE battery life, extended discontinuous reception (eDRX) and Power Saving Mode (PSM) was introduced by 3GPP in Release 13. In eDRX mode, UE sleeps with disabled Radio Resource Control (RRC) connection and receives regular paging messages from the core network 4 . Although, UE is not reachable in PSM mode, but it is still registered to the core network.…”

“…To avoid excessive signaling a grouping based DRX mechanism for power efficient NB‐IoT system was proposed by Xu and Zhang 23 . Rastogi et al 4 discussed the architecture of NB‐IoT and proposed a SMM with the introduction of an auxiliary state to transmit small data transmission. Moreover, based on eDRX mode and PSM mode in RRC idle mode, the performance of the model was analyzed.…”