Rushing Full Speed with LTE-Advanced is Economical -- A Power Consumption Analysis

TL;DR

This paper analyzes the power consumption implications of LTE-Advanced's Carrier Aggregation, showing that it can save energy during high data rate transmissions despite increased hardware complexity.

Contribution

It introduces an enhanced power consumption model considering environment and mobility, demonstrating that Carrier Aggregation can reduce power use under certain conditions.

Findings

CA can save 31% power when doubling data rates for large files.

Power savings of 25% are achievable with moderate data rate increases, regardless of mobility.

Intra-band CA consumes less power than inter-band CA.

Abstract

Boosting data rates in LTE mobile networks is one of the key features of LTE-Advanced. This improved user experience is achieved by Carrier Aggregation (CA), in which the available spectrum of an operator is bundled out of several frequency bands. Accordingly, the user equipment has to supply multiple reception chains and therefore consumes considerably more power during a transmission. On the other hand, transmissions terminate faster, which enables a quick switchover into energy-saving mode. In order to examine these opposed facts, empirical analyses of existing devices are first carried out. Subsequently, we present a new CA enhancement of an existing context-aware power consumption model which incorporates the development density of the environment and the mobile device mobility. Based on the extended model we perform a detailed power consumption analysis and show that CA leads to power savings of 31% if the data rate doubled for large file transmissions. In addition, we show that CA can lead to power savings even from a data rate increase of 25%, regardless of mobility and urban development density. Besides, the measurement results show that CA operated in the same band leads to a lower power consumption than inter-band CA.