To allow access to the network at all times a base station has to continuously stay active. While being active, a base station does not usually transmit data constantly. Typically, the base stations either send out lots of data or barely anything at all, yet, the network is actively drawing power the whole time.
Succeeding in lowering the power consumed when the data rate is often so low would therefore lead to great benefits, both economically and environmentally.The process of how to dynamically change from a capacity optimized mode to an energy optimized mode as well as when to do this change is studied in this project for LTE.
By using methods such as antenna muting and psi-omni coverage, the power consumption can decrease. These solutions however also decreases performance, and has to be activated with great care in mind not to cause any major impact on user performance. The dynamic configuration is dependent on the load of the system, changing to an energy efficient mode when traffic is low and to a capacity optimized mode when the network needs to supply high data rates.
Simulations show that most energy savings can be found in rural and urban environments. Dynamic antenna muting achieved, summarizing macro environments, 24.9% energy savings with 95.27% downlink data rates compared to the reference case of using sector mode continuously i.e MIMO. In the same environments, dynamic psi-omni coverage together with antenna muting achieved energy savings of 43.8% with 89.3% downlink data rates compared to typical sector mode. Traffic rates are based on future demands in Europe by 2015, assuming that 20% of the subscribers are downloading 900 MB/h and the other 80% subscribers, at 112.5 MB/h.
Source : Uppsala University
Author : Al-Husseiny, Zeid