Dept. of Comput. Sci. & Inf. Eng., National Taiwan Univ.Yang, Shih-HsienShih-HsienYangTseng, Hung-WeiHung-WeiTsengWu, E.H.K.E.H.K.WuGEN-HUEY CHEN2007-04-192018-07-052007-04-192018-07-052005-12http://ntur.lib.ntu.edu.tw//handle/246246/200704191001166In this paper, we propose U-MAC, a medium access control protocol designed for wireless sensor networks. Nowadays, wireless sensor network are formed by a great quantity of sensor nodes, which are generally battery-powered and may not recharge easily. Consequently, how to prolong the lifetime of the nodes is an important issue while designing a MAC protocol. However, lowering the energy consumption may result in higher latency. Addressing on such tradeoff, U-MAC balances the tradeoff by utilization based tuning of duty cycle and selective sleeping after transmission. The experiment results show that our proposed U-MAC saves energy about 43% and reduce latency by 65% from S-MAC in a chain topology. In the cross topology, U-MAC also achieves 32% energy saving and 45% latency reduction from S-MAC.application/pdf460035 bytesapplication/pdfen-US[SDGs]SDG7journal article10.1109/GLOCOM.2005.1578377http://ntur.lib.ntu.edu.tw/bitstream/246246/200704191001166/1/01578377.pdf