Accurate Energy-Efficient Power Control for Uplink NOMA Systems under Delay Constraint

TL;DR

This paper proposes a novel energy-efficient power control scheme for uplink NOMA systems in 5G machine-type communications, ensuring delay constraints and diverse QoS requirements through advanced modeling.

Contribution

It introduces a new power control method utilizing effective bandwidth and capacity models, with two analytical models for energy efficiency maximization under delay constraints.

Findings

Achieves exact delay QoS guarantees for NOMA systems.

Enhances energy efficiency for MTC devices with mode switching.

Validates effectiveness through simulations.

Abstract

Machine-type communications (MTC) devices in 5G will use the Non-orthogonal multiple access (NOMA) technology for massive connections. These devices switch between the transmission mode and the sleep mode for battery saving; and their applications may have diverse quality of service (QoS) requirements. In this paper, we develop a new uplink energy-efficient power control scheme for multiple MTC devices with the above mode transition capability and different QoS requirements. By using the effective bandwidth and the effective capacity models, the system's energy efficiency can be formulated as the ratio of the sum effective capacity to the sum energy consumption. Two new analytical models are used in system's energy efficiency maximization problem: 1) two-mode circuitry model and 2) accurate delay-outage approximation model. Simulation shows our proposed scheme is capable of providing exact delay QoS guarantees for NOMA systems.