Overview of MAC Protocols in Wireless Sensor Networks
无线传感器网络MAC协议研究进展

Wireless sensor networks(WSNs)are different from traditional networks and are highly dependent on appli- cations.One of the main goals of WSNs is to maximize the lifetime of the whole network as well as to use the constrained node resources efficiently,such as energy,memory,and computing capacities.Traditional MAC protocols cannot be applied efficiently to WSNs.Therefore,many new MAC protocols have been designed specifically according to WSNs characteristics and different applications.After introducing the characteristics of WSNs,this paper first describes the sensor network properties that are crucial to the design of MAC protocols.Then,the key mechanisms,virtues,and short- coming of the existing representative MAC protocols are analyzed,and their performances are compared.The results show that there is no MAC layer protocol that can be accepted as a standard.A good MAC protocol is that it has the ability to make tradeoffs between energy-efficiency and other performances of WSNs according to application conditions. Finally,the future research strategies and trends of MAC protocols in WSNs are summarized.