Adaptive MAC with scheduled sectorial access at sinks (SSAS) in Wireless Sensor Networks

This paper addresses the trend in wireless sensor network applications of increasing node density and multi-hop communications that result into extremely challenging design constraints. SSAS, an adaptive hybrid localised sink-oriented Routing/MAC protocol is proposed. It offers a self-configuration scalable solution for large random sensor networks and attempts to alleviate multi-hop congestion problems. The strength of the SSAS protocol is based on the scheduled access at the sinks and the enhancement of the number of one-hop sinks´ neighbours by profiting directional antenna capabilities. By means of modelling off-the-shelf sensor node architecture with realistic radio channel assumptions and the use of network simulations, this paper shows significant improvements of SSAS (such as 10 times higher network lifetime) compared to other techniques such as pure contention-based alternative (C-MAC), B-MAC and LEACH.