適用於資源極端侷限感測器之快速多跳資料擷取協定設計與實作

The Design and Implementation of a Fast Multi-hop Data Acquisition Protocol for Extremely Resource-Constrained Sensor Platforms

楊濠駿(Hao-Jun Yang)

指導教授 ： 金仲達

國立清華大學/電機資訊學院/資訊系統與應用研究所/碩士(2010年)

摘要

無線感測網路通常被建構成資料收集樹來將感測資料收集至匯聚節點。在樹當中，距離匯聚節點較近的感測器節點會幫忙距離較遠的感測器節點傳遞資料。這種多跳收集資料的通訊方式對無線感測網路是很重要的，但是在硬體資源極端侷限的感測器平台上，卻有實現的困難，尤其是在高頻寬的應用情境下。一方面，由於硬體資源的限制，讓這種平台在缺乏接收訊號強度指示裝置下，無法進行有效率的高頻寬無線通訊；這使得通訊排程在這情況下變得非常重要。另一方面，因為極小的內建記憶體空間，只能允許非常簡單的、經過適當設計的通訊協定的運作。本篇論文針對這些挑戰提出一些具體的解決方案，包括一個以Token為基礎的TDMA網路排程方法，並整合多頻道通訊以及路由平衡樹的建立來縮短排程的延遲以提高資料傳輸率。藉由在ECO感測器平台上的實作驗證了我們所提出方法的可行性。當與另一特別為ECO所設計的單跳快速資料擷取協定EcoDAQ比較時，我們的方法可以提高71%的資料傳輸率。

關鍵字

無線感測網路

並列摘要

Wireless sensor networks (WSNs) are often structured as a data collection tree to collect sensory data into the sink node. Sensor nodes in the middle of the tree will help relay data for those nodes further away from the sink. This sort of multi-hop communication is very essential for WSNs. However, it is challenging to perform multi-hop communication on extremely resource-constrained sensor platforms, especially under high bandwidth. For one thing, the limited hardware resources may limit such platforms to do without the Received Signal Strength Indication facility, which makes communication scheduling very important. For another thing, the extremely small built-in memory allows only very simple and carefully designed communication protocols. This thesis addresses these challenges and introduces various techniques to overcome them, including a Token-based TDMA scheduling scheme integrated with multi-channel communication and balance tree construction to minimize the schedule frame for high data rate requirement. We take the ECO sensor platform as an example and show the feasibility of the proposed techniques through real implementation. When compared with the EcoDAQ protocol, which is a fast one-hop data acquisition protocol designed specially for ECO, our proposed techniques gain a 71% improvement in data throughput.

並列關鍵字

WSN ； TDMA ； FDMA

參考文獻

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