An Analysis of IEEE 802.11 DCF and Its Application to Energy-Efficient Relaying in Multihop Wireless Networks
Issue No. 10 - October (2011 vol. 10)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TMC.2010.239
Canan Aydogdu , Bilkent University, Ankara
Ezhan Karasan , Bilkent University, Ankara
We present an analytical model for the IEEE 802.11 DCF in multihop wireless networks that considers hidden terminals and accurately works for a large range of traffic loads. An energy model, which considers energy consumption due to collisions, retransmissions, exponential backoff and freezing mechanisms, and overhearing of nodes, and the proposed IEEE 802.11 DCF analytical model are used to analyze the energy consumption of various relaying strategies. The results show that the energy-efficient relaying strategy depends significantly on the traffic load. Under light traffic, energy spent during idle mode dominates, making any relaying strategy nearly optimal. Under moderate traffic, energy spent during idle and receive modes dominates and multihop transmissions become more advantageous where the optimal hop number varies with processing power consumed at relay nodes. Under very heavy traffic, where multihopping becomes unstable due to increased collisions, direct transmission becomes more energy efficient. The choice of relaying strategy is observed to affect energy efficiency more for large and homogeneous networks where it is beneficial to use multiple short hops each covering similar distances. The results indicate that a cross-layered relaying approach, which dynamically changes the relaying strategy, can substantially save energy as the network traffic load changes in time.
IEEE 802.11 DCF, analytical model, energy-efficient relaying, multihop wireless networks, hidden terminal.
E. Karasan and C. Aydogdu, "An Analysis of IEEE 802.11 DCF and Its Application to Energy-Efficient Relaying in Multihop Wireless Networks," in IEEE Transactions on Mobile Computing, vol. 10, no. , pp. 1361-1373, 2010.