Global Energy-Throughput Evaluation of Multihop Communication for Indoor IEEE 802.11a

─ Future wireless communication devices are expected to support a broad range of exciting applications, while coping with stringent energy budget requirements. Delivering at each moment in time the just required performance with minimal energy consumption is a promising energy management technique to enable pervasive wireless networking. Considering transmission energy only, the use of multiple small hops results in a decrease of the energy consumption. On the other hand, decreasing the transmission rate of a single hop similarly results in a decrease of the energy needed to deliver a bit. In this paper we compare the use of multiple small hops with a single large hop in the EnergyThroughput design space. In contrast with earlier work, realistic transceiver models are used, that cover the complete MAC, transmit and receive chain and support different transmission rates. Results show that, when considering the protocol and receive overheads, the use of multiple hops in indoor environments is only optimal in the Energy-Throughput space for distances larger than 30m. Hence, the use of multiple hops is more a technique to enhance the range or robustness rather than a technique to increase the energy efficiency of wireless communications. Index Terms ─ Energy efficiency, multi-hop communication, 802.11a WLAN, Cross-layer research