  Improved mobile device battery lifetime and latency mini-mization are
critical requirements for enhancing the mobile broadband services and user
experience. Long-term evolution (LTE) networks have adopted discontinuous
reception (DRX) as the baseline solution for prolonged battery lifetime.
However, in every DRX cycle, the mobile device baseband processing unit
monitors and decodes the control signaling, and thus all instances without any
actual data allocation leads to unnecessary energy consumption. This fact
together with the long start-up and power-down times can prevent adopting
frequent wake-up instants, which in turn leads to considerable latency. In this
work,a novel wake-up scheme is described and studied, to tackle the trade-off
between latency and battery lifetime in future 5G networks, seeking thus to
facilitate an always-available experience, rather than always-on. Analytical
and simulation-based results show that the proposed scheme is a promising
approach to control the user plane latency and energy consumption, when the
device is operating in the power saving mode. The aim of this article is to
describe the overall wake-up system operating principle and the associated
signaling methods,receiver processing solutions and essential implementation
aspects. Additionally, the advantages compared to DRX-based systems are shown
and demonstrated, through the analysis of the system energy-efficiency and
latency characteristics, with special emphasis on future 5G-grade mobile
devices
