Smart Small Cell Wake-Up Field Trial: Enhancing End-User Throughput and Network Energy Performance

Field trial measurements of small cell sleep mode with three different wake-up solutions are presented in this paper. A small heterogeneous LTE test network consisting of one macro base station and four small cells was deployed in Bundang, South Korea. Two UEs, one stationary and one moving, were used in the field trial. The studied solutions were (1) uplink interference based stand-alone small cell activation; (2) macro- assisted load-based small cell activation; and (3) macro-assisted load-based and timing advance-based small cell activation. Solution 1 was evaluated in a scenario where the same frequency band is used in the macro and small cell layers and the results show that Solution 1 provides an average reduction in energy consumption of 10% as well as a user throughput increase of 24% compared to a reference case without small cell sleep mode. For solutions 2 and 3 different frequency bands were used for the small cells and the macro layer and here the energy reduction gains were 16% and 23% respectively while the increase in user throughput was 28% and 51% respectively.