無線感測網路的目標追蹤之研究

The Study of Target Tracking in Wireless Sensor Networks

陳寶珠(Pao-Chu Chen)

指導教授 ： 陳啟彰

義守大學/電機資訊學院/資訊工程學系/碩士(2016年)

摘要

目標追蹤是無線感測網路的研究中一項很重要的議題，例如在監測敵人入侵、野生動物之研究、特定人物的追蹤等，需要持續追蹤、監測目標的相關資訊。以往的相關研究中提出了許多解決的方法，為了節能較常採用的方法是以預測的方式喚醒感測器，只有接下來可能感測到目標的感測器需要被啟動。但為了節省能耗，喚醒的感測器可能會過於稀少，並且預測本身具有不確定性，有時候不能滿足追蹤目標的目的因而遺失目標。另外有些方法為了要保證目標不遺失，反而導致感測感測器耗電過快。因此目標追蹤需要在準確率與節能之間做出取捨。
本論文提出一個追蹤目標的系統，先將整個感測區域劃分為數個六角形叢集，每個叢集會輪流選出叢集頭，而被選為叢集頭的感測器要持續醒著以監測目標有無進入感測區域，當叢集頭第一次檢測到目標時會喚醒此叢集中的所有感測器，感測器會將偵測到目標的相關資訊，如自身位置、與目標的距離、自身能量等資訊傳送給叢集頭，而叢集頭會再依據我們提出的Hexagon Routing with Repair (HRR)演算法將感測資訊路由回基地台，基地台依據目標目前的位置、最大速度計算出目標可能的移動區域，而基地台再喚醒與目標小於一定距離的叢集，依此來持續追蹤目標，達到節能又準確的目標追蹤。

關鍵字

無線感測網路 ； 目標追蹤 ； 資料路由 ； 叢集網路 ； 目標定位 ； 路徑規劃演算法

並列摘要

Target tracking is one of the very important issues in wireless sensor network research. Its applications include monitoring enemy invasion, wildlife research, tracking a specific person, etc. Previous studies proposed a number of methods for target tracking which focused on saving energy. Some of them applied prediction approaches to wake up idle sensors. Only the sensors which detect the target need to be activated next time. However, in order to save energy, the number of wake-up sensors may be too few. Moreover, prediction approaches inherently have uncertainty, and sometimes cannot meet the requirements of tracking targets and therefore miss the target. Some other methods, in order to ensure the target not lost, may drain the energy of sensors too fast. Therefore, the methods of target tracking usually face a tradeoff between accuracy and energy efficiency.
This paper proposes a target tracking system, this system uses regular hexagons to tessellate the entire sensing area, and each hexagon forms a cluster. Every cluster will elect a cluster head in turn, and each cluster head keep active to sensing target. Cluster head will wake up all sensors in the cluster when target into its cluster first time. Each sensor needs to send its sensing information to the cluster head, and each cluster head use our Hexagon Routing with Repair (HRR) algorithm to route its sensing information to the center of base station. The base station uses the information of the current position and maximum velocity of the target to calculate the next possible location of the target. Our system can usually wake up the suitable sensors of the nearby clusters to keep track of the target, and therefore achieve both requirements of energy efficiency and location accuracy of target tracking.

並列關鍵字

Wireless Sensor Networks ； Target Tracking ； Data Routing ； Cluster Networks ； Localization Problems ； Path Planning Algorithm

參考文獻

[3]Yash Sharma, “What is wireless sensor network (WSN) technology”, 2015, https://www.quora.com/What-is-wireless-sensor-network-WSN-technology, access on 2015/12/5

[4]C.-C. Chen and T.-C. Lin, “A Low-Cost Anchor Placement Strategy for Range-Free Localization Problems in Wireless Sensor Networks,” International Journal of Distributed Sensor Networks, vol. 2013, pp. 1-12, 2013.

[5]X. Xing, G. Wang, and J. Wu, “Herd-Based Target Tracking Protocol in Wireless Sensor Networks,” in Wireless Algorithms, Systems, and Applications, vol. 5682, pp. 135-148, 2009.

[6]Wensheng Zhang and Guohong Cao, “DCTC: dynamic convoy tree-based collaboration for target tracking in sensor networks,” IEEE Transactions on Wireless Communications, vol. 3, pp. 1689-1701, September 2004.

[8]T. Alhmiedat, A. O. Abu Salem, and A. Abu Taleb, “An Improved Decentralized Approach for Tracking Multiple Mobile Targets through ZigBee WSNs,” International Journal of Wireless & Mobile Networks, vol. 5, pp. 61-76, 2013.