具高適應性移動型無線感測器網路之動態路由及存取控制協定設計與實現

本研究設計且實現一套具高適應性移動型無線感測器網路之動態路由及存取控制協定(High Adaptive Dynamic Topology and Medium Access Control Protocol for Mobile WSN, HADTM)，並將本協定建構於樹狀拓樸之上，透過樹狀拓樸高適應性的優勢，可順利將各種不同移動行為之節點的資料穩定且順利回傳至後端閘道器。本研究之動態路由演算法，使用訊號強度以及網路層數兩項參數，賦予節點動態調整回傳路徑之能力，使節點不論移動至任何位置，皆可自主找尋適當之回傳路徑。除此之外，針對新加入或離開網路之節點，本協定內之動態路由規劃機制亦可有效處理此種問題，節點於任何時刻需要加入網路時，皆可迅速融入網路並執行監測之任務。若當有節點欲離開網路時，HADTM亦可確保離開節點所挾帶之子節點不因失去父節點而導致回傳路徑遺失，網路內部所有節點依舊可順利將資料回傳至後端閘道器。時槽規劃方面，本研究亦提出高適應性之時槽規劃設計，透過此設計可有效解決節點移動時之不可預測性所產生的時槽混亂問題，且節點每回合之時槽規劃皆可動態調整，使資料量與時槽數目吻合，達到最有效率之時序應用。此外，吾人加入通知機制於時槽規劃，實驗證實本協定之時槽規劃相較傳統時槽規劃減少約30 %之時間浪費。本研究克服分散式路由實作困難的挑戰，將HADTM實作於Octopus II。透過分散式路由的優勢，節點可自主運算，迅速且即時找尋適當的回傳路徑，可有效降低延遲，適應移動節點各種不同之移動行為。經實驗證實，本研究提出之HADTM於單一移動節點或是多顆移動節點於室內移動時，不論是移動節點或是整體網路，其資料接收率皆高達95 %以上。此外，在網路綜合測試實驗上，證實無論發生節點新加入或是離開網路之事件，其網路資料接收率皆高達96 %以上。

關鍵字

分散式動態路由；高適應性；移動型無線感測器網路；彈性時槽

並列摘要

In this study, a high-adaptive dynamic topology and medium access control protocol for mobile wireless sensor networks (HADTM) was designed and implemented. HADTM based on the tree topology is greatly adaptive to dealing with many mobile problems. For the dynamic routing algorithm, this study combines the receive signal strength indication (RSSI) and hop count to dynamically adjust nodes routing paths. Regardless of where the nodes move, they can select appropriate routing paths to transmit data toward the gateway. In addition, when new nodes are added to networks, they can be quickly included to the network schedule and start to monitor. When the nodes leave the networks, HADTM can ensure that the child nodes transmit the data to the gateway with no mistakes. For the time slot, this study proposes a flexible process schedule-based MAC design. This unusual design can be an effective solution to the time slot chaos caused by unpredictable mobile states. Also, a notification mechanism is designed in this study to achieve the most effective time schedules, reducing approximately 30% of the waste of time. This study implements HADTM on the Octopus II and overcomes challenges of the distributed routing. Through the advantages of distributed routing, nodes can calculate routing paths automatically and in real-time to reduce latency. According to the results of the experiments, for both single mobile node and multiple mobile nodes, the delivery package rate (DPR) of the networks is up to 95 %. Furthermore, the experiments verify that DPR is also up to 96%, regardless of whether nodes join or leave the networks. Above of all the experimental results, the HADTM protocol can also support mobile wireless sensor networks to develop a variety of applications.