CF-MAC and H-MAC protocols for energy saving in wireless ad hoc networks

Wireless ad-hoc networks are widely adopted in contexts where a temporary network connectivity is required. The distributed and flexible architecture of these networks is a key strength but, due to the scarce energy resources available at each station, innovative energy efficient MAC algorithms are required in order to extend as much as possible network lifetime, while providing acceptable throughput and delays. Starting from the theory of balanced incomplete block design (BIBD), this paper proposes two power efficient MAC algorithms, which will be referred to as hybrid MAC (H-MAC) and collision free MAC (CF-MAC). The H-MAC algorithm combines standard IEEE 802.11 power saving features with a BIBD-based schedule. CF-MAC, instead, is a fully BIBD-based protocol, which allows a collision free transmission over a shared wireless medium. The performance of the proposed MAC schemes have been compared with the standard 802.11 power saving algorithm using computer simulations, showing that: (1) CF-MAC improves the overall network throughput and reduces the energy consumption with respect to the 802.11 power saving while guaranteeing acceptable delays; (2) H-MAC reduces the energy consumption with respect to 802.11 power saving while guaranteeing the same throughput, at the expense of higher delays.