Design and Analysis of Robust Data Gathering MAC in Wireless Sensor Networks

• Main Authors: Yong-Qing Wu, 吳勇慶
• Other Authors: Chuan-Ching Sue
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/75690687848808365476

碩士 === 國立成功大學 === 資訊工程學系碩博士班 === 94 === Wireless sensor networks are composed of a large number of sensor nodes. Since sensor nodes are generally battery-operated, energy consumption is very important. Therefore, active/sleep duty cycle schemes are proposed to reduce energy consumption. Although low duty cycle schemes can reduce energy consumption, it will increase packet delivery latency. DMAC using the staggered wakeup schedule can achieve both low latency and low energy consumption with the low duty cycle scheme. However, the data gathering tree built by DMAC is fixed permanently. A fixed data gathering tree can't adapt to the variability in the environment of wireless sensor networks, and it needs to be reconstructed frequently to suit the current environment. For example, the interference is a factor that will change the environment because it changes node connectivity of wireless sensor networks. In this paper, we propose a Robust-DMAC (RDMAC) which can dynamically construct the data gathering tree according to the changing environment. Because RDMAC separates the formation of the data gathering tree from the arrangement of the wakeup schedules, it can easily construct a new data gathering tree without adjusting nodes' schedules. As for the transmission aspect, since RDMAC adopts the staggered wakeup schedule suggested in DMAC, we can apply these transmission mechanisms (duty cycle adaptation, data prediction, More-To-Send packet) proposed by DMAC with few modifications. From simulation results in variable environments affected by interference, it is shown that RDMAC performs closely with DMAC in effective energy consumption and has remarkable improvement in packet arrival ratio, network throughput, and packet delivery latency over DMAC.