Exploiting a meeting channel to interconnect 802.15.4-compliant mobile entities: discovery and association phases

Several industrial applications require mobile robots to exchange data between them or with a static sink. In this paper, we consider a fleet of mobiles moving in an environment, carrying sensors and actuators. As they move close to a manager, the mobiles exchange data with this static entity. This communication is performed on a meeting channel, different from the channel used for the intra-mobile communications, in order to avoid interferences and to reduce contention. We study how nodes carried by mobiles can associate to the manager network. We show that the association procedure of the IEEE 802.15.4 standard is not adapted to this scenario, because it requires too much time and reduces the time remaining for the communication. Thus, we propose a new association procedure which enables a fast association of nodes. Our results allow us to build an efficient architecture for a wireless personal area network constituted of mobile sensors and static managers.