Task description and Expected results
The task on technical and architectural solutions assumes that the trend in planning of future mobile networks is the deployment of an increasing number of small-cells (SC s) within the coverage area of existing macro cells. In this context, it identifies the resources available for the communication and the assignment of resources to the various entities involved in the establishment of a multi-link communication. It defines the schemes that will take advantage of spectral opportunities to reduce energy consumption, such as the use of lower interference spectrum, the dynamic tailoring of communications characteristics to match available bands (e.g., the use of appropriate frequency dependent on propagation characteristics and required coverage range), the use of spectrum aggregation, and the appropriate autonomous configuration of localized coverage elements in shadowed areas (e.g., cognitive femto-cells, cognitive relays, etc.), among others. Moreover, it considers spatial opportunities such as the potential to power down some cells, the use of cell zooming capabilities to maintain coverage with the minimal amount of hardware operational at any one time, the deployment of relays, and the use of cooperative transmissions to save energy. TSK9
& 10 will consider that some cellular elements, e.g., relays, may be powered by renewable energy sources and will therefore attempt to maximize the use of renewable energy whilst ensuring that QoS requirements are maintained.
Finally, this task considers the architectural aspects that are necessary to achieve the identified technical solutions, e.g., frequency adaptability, handover and mobility mechanisms in cellular reconfigurations.
Task 9.2 Identification of energy saving opportunities
This task will develop means to identify spectral/spatial optimization opportunities in SC Ns. This means consider the utilization of renewable energy resources, as well as minimization of the implied necessary hardware density. They aim to satisfy QoS and user experience requirements while still saving energy.
1) Discovery of spectrum opportunities
Radio spectrum real-time usage characterization plays an important role in identifying opportunities to predict future energy consumption reduction in communication systems.
consumption reduction in communication systems.
First, one aims to take advantage of information that is already available to the network as might be obtained through feedback information from terminals and base stations (traffic, QoS, usage of spectrum), and through general network knowledge of the spectral configuration of the network elements.
Second, advanced spectrum sensing schemes (interference awareness, power levels) are considered while learning about sensed spectrum characteristics, so that it is possible to predict better configurations going into the future and match to varying traffic requirements.
2) Discovery of spatial opportunities
It involves the identification of spatial variations in traffic loading and/or locations where traffic load is lower than network capacity, such that cells can be powered down. The spatial solutions identified in Task 9.1 can also be employed. Discovery of these opportunities may involve spectrum sensing solutions in some scenarios, e.g., to ascertain localized power levels hence potential spatial transmission tuning for deployed elements.
Mem bers of the research team in this task: (BI) Bolseiro de Investigação (Mestre) 2; (BI) Bolseiro de Investigação (Mestre) 3; (BI) Bolseiro de Investigação (Mestre) 6;
(BPD) Bolseiro de Pós-Doutoramento 1; António Jorge da Silva Morgado; Daniel Luís Silveira Robalo; Fernando José da Silva Velez; Norberto José Gil Barroca; Nuno Miguel Gonçalves Borges de C arvalho;
