Smart multihop communication for wireless sensor networks

Inhalt:
Sensor networks are made up of a large number of small sensing nodes which cooperatively perform complex tasks. The interaction between the nodes is based on wireless communication. Since the energy is a scarce and usually non-renewable resource, the functionality of sensor networks must be viewed from low-power perspective. Medium access control (MAC) mechanism has a significant impact on the energy efficiency. Currently available MAC protocols for wireless sensor networks can be broken down into two major types: contention based and scheduling based. While under contention-based protocols nodes compete among each other for channel access, scheduling-based schemes rely on prearranged collisionfree links between nodes. In this paper we discuss a novel MAC protocol for wireless sensor networks, ALSMAC. The protocol achieves good scalability and collision avoidance by utilizing contention-based advertising slots mapped to scheduled-based transmission slots.