Fast Small Cell Access

Offloading traffic to small cells is one of the key enablers in achieving high peak data rates in a heterogeneous cellular network deployment. However, to maintain the benefit of robust mobility offered by the macro cell layer, ideally the connection to the macro cell is still maintained even when bulk of the user data is offloaded and served in a higher capacity small cell. In this paper, we introduce and evaluate a solution based on UE performing additional small cell measurements in idle state. These additional measurements naturally have a cost as additional energy consumption in the UE, but enable much faster small cell setup after there is data. However, due to the substantially better energy efficiency of data transmission in a small cell, our results indicate that a positive trade-off is possible in a typical scenario. The performance gains are compelling: We observe user perceived throughput up to 5-10 times higher, while still experiencing a lower average UE energy consumption.