On the impact of small cell discovery mechanisms on device power consumption over LTE networks

Small Cells are under extensive investigation as a potential solution to meet the increasing capacity demand due to ever growing data traffic over cellular networks. The architecture of small cells is still under discussion, various architectures have been proposed based on potential use cases. One of the most important use cases is to deploy small cells on a different frequency than that of the macro cell to offload traffic. Small cell discovery in this type of inter-frequency scenario is an open research problem. Aggressive scanning mechanisms may result in faster discovery of small cells and higher user throughput as well as higher macro cell capacity due to potentially increased offloading opportunity. However, frequent scanning may also result in higher power consumption for the device. Therefore, a tradeoff between offloading opportunity and device power consumption seems inevitable in practice. In this paper, we analyze the trade-off between the offloading capacity and device power consumption due to inter-frequency scanning mechanism for small cell discovery. Our findings show that although increasing the frequency of inter-frequency scanning does result in increased power consumption due to scanning, it actually lowers the total power consumed by the device since it leads to offloading to small cells, where the device consumes less overall power due to better coverage.