Evaluating an energy-efficient radio architecture for opportunistic communication

Abstract

Abstract-A major challenge for wireless networks is to minimize the energy consumption in the mobile devices. This work evaluates potential performance gains of a dual-radio architecture in which a low power radio is used to wake up the primary high power radio. Our targeted domain is opportunistic communication directly between devices. We show that it can significantly reduce the energy consumption at a price of slightly decreased goodput. We also examine the effect of the MAC protocol on the performance of the dual-radio system and we point out that in dense scenarios MAC layer protocols, such as of 802.15.4, do not perform well. We observe that information on device density of an environment can be used to address this shortcoming.

Energy savings in opportunistic networks

“…This is due to the characteristics of the low-power 802.15.4 radio which is unable to perform the node and service discovery in areas with high density. (For more explanation see [7].) However, in Fig.…”

“…Such dual-radio architectures only wake up the high-power radio when a useful contact has been found. We have also investigated this possibility in a previous work [7], and the results showed that it may prolong the battery lifetime of nodes in opportunistic network. However, since a secondary radio is often not available on personal mobile devices, the applicability is limited.…”

“…The highpower radio is completely suspended when not in use; it is associated with a modest (2 s) delay for turning on, but does not consume energy when suspended. A detailed description of the dual-radio can be found in [7]. 4) Benchmark (BM) -an idealized system in which global knowledge is assumed for the location and the subscriptions of each node in the system; such a system concentrates on evaluation of the energy consumed for the actual data exchange and abstracts the discovery phase, thus it provides a lower bound for the energy consumption and an upper bound for the goodput.…”

“…In our previous work [7] we explored a solution based on a dual-radio architecture for minimizing energy consumption. In this paper we look into another strategy for minimizing energy consumption on a single-radio system: duty-cycling.…”