无线传感网络追踪系统的位置更新机制

In traditional tracking systems, the mobiles report their location to server periodically, which will result in high packet loss rate and rapid energy depletion as the number of mobiles increases. Actually, in practical tracking applications, we observe that nodes are often close to others. Hence, we conceive to pick out some nodes to report periodically as delegates for their adjacent ones. By exploiting this thought, we propose an Effective Location Updating Mechanism (LUM) for tracking systems in wireless sensor networks. In our method, mobiles update location information through two kinds of delegates: remote and nearby delegates. In LUM, only delegates report location periodically instead of each mobile node. Therefore, LUM can save energy greatly through reducing the message complexity. To demonstrate the performance of LUM, we deploy a prototype system with 38 Micaz Motes. The results show that LUM outperforms traditional approaches by at least 45% less message transmission and 48% fewer energy depletion on average.