MLMAC – An Adaptive TDMAMAC Protocol for Mobile Wireless Sensor Networks
Stephan Mank, Reinhardt Karnapke and Joerg Nolte
Today, wireless sensor networks are typically realized using cheap radio transceivers offering low bandwidth communication only. When physical events in the real world trigger spontaneous communication in many nodes, the single communication channel is under heavy load and many messages are lost due to collisions. CSMA/CA schemes are well suited to spontaneous communication, but do not provide a high channel utilization under heavy load. TDMA protocols have some conceptual advantage here, but in the case of mobile sensor nodes they need to be adaptive and establish TDMA schedules on demand. In this paper we introduce the MLMAC (mobile LMAC) protocol. MLMAC is a novel TDMA based MAC protocol that can react on changing radio neighborhoods in mobile networks. In addition to the conceptual description of MLMAC, we also present the results of real experiments with a group of mobile sensor nodes based on RCX robots.
Keywords: MAC protocols, self organization, wireless sensor networks.