Cellular traffic offloading onto network-assisted device-to-device connections

TLDR

Operators are deploying 4G, yet many anticipate it will still fall short of future mobile traffic demands, prompting a shift toward smaller cells such as picocells, which entail significant CAPEX and OPEX. The study proposes to offload cellular traffic onto direct device‑to‑device connections to avoid additional CAPEX and OPEX. This is achieved by routing traffic through D2D links whenever users are in proximity, leveraging existing cellular and WiFi capabilities. Because most client devices can simultaneously use cellular and WiFi, the authors expect the greatest immediate gains to come from utilizing unlicensed bands.

Abstract

While operators have finally started to deploy fourth generation broadband technology, many believe it will still be insufficient to meet the anticipated demand in mobile traffic over the coming years. Generally, the natural way to cope with traffic acceleration is to reduce cell size, and this can be done in many ways. The most obvious method is via picocells, but this requires additional CAPEX and OPEX investment to install and manage these new base stations. Another approach, which avoids this additional CAPEX/OPEX, involves offloading cellular traffic onto direct D2D connections whenever the users involved are in proximity. Given that most client devices are capable of establishing concurrent cellular and WiFi connections today, we expect the majority of immediate gains from this approach to come from the use of the unlicensed bands.