Store, carry and forward for energy efficiency in multi-hop cellular networks with mobile relays

Abstract The wide scale adoption of smartphones is boosting cellular data traffic with the consequent capacity constraints of cellular systems and increase in energy consumption. A significant portion of cellular data traffic can be deemed as delay tolerant. Such tolerance offers possibilities for designing novel communications and networking solutions that can accommodate the delay tolerant cellular data traffic while reducing their impact on the overall cellular capacity and energy consumption. In this context, this work studies the use of opportunistic store, carry and forward techniques in Multi-Hop Cellular Networks (MCN) to reduce energy consumption for delay tolerant traffic. The study focuses on two-hop MCN networks using mobile relays (MCN-MR), and identifies the optimum mobile relay location and the location from which the relay should start forwarding the information to the cellular base station in order to minimize the overall energy consumption. The study shows that the use of opportunistic store, carry and forward techniques in MCN-MR can significantly reduce energy consumption compared to other solutions, including traditional single-hop cellular systems or direct contact store, carry and forward solutions.This work is supported in part by the Spanish Ministry of Economy and Competitiveness and FEDER funds (TEC2011–26109)and the Local Government of Valencia with reference ACIF/2010/161 and BEFPI/2012/06

Inter-cell interference reduction via store carry and forward relaying

The integration of mobile relays in cellular networks has been recently envisioned as a way of increasing system capacity, coverage and reducing communication energy consumption. In [1] we studied how store carry and forward (SCF) relaying within the cell can be utilized as an underlay message forwarding mechanism to achieve system wide energy savings. In this paper, by deriving optimal routing policies to reduce either the total energy consumption or the total transmit power, we show that the SCF relaying scheme reduces considerably inter-cell interference. We detail the factors affecting the maximum interference reductions, including the delay tolerance of elastic data traffic and flow characteristics of vehicles in the road network which in this case are used as mobile relay nodes