無線感測器平台介面設計技術

Wireless Sensor Interface Design Technique

呂佳惠(Chia-Hui Lu)

指導教授 ： 許雅三 ； 周百祥

國立清華大學/電機資訊學院/電機工程學系/碩士(2008年)

摘要

由於無線感測網路所提供的方便性，無線感測網路已漸漸被廣泛應用在環境監測、工業運用、健康照護以及居家應用等等，不同種類的感測器和無線感測平台也隨之發展。面對琳瑯滿目的感測器，如何設計出一個對於使用者來說最合適的無線感測器介面平台，成了設計無線感測平台的一個重點。
　　一般說來，無線感測器介面的功能為在固定的頻率下取樣感測器輸出的感測資料並將此資料轉成微處理器可處理的資料格式。它會影響到整個無線感測平台的消耗功率、資料精準度、以及取樣頻率等等。
　　目前市面上感測器輸出格式可分為類比輸出、數位輸出、電容量輸出以及高階協定輸出。在本論文中，我們提供了類比輸出以及數位輸出的無線感測器介面平台架構；並將元件特性參數化，經由實驗整理出這些參數和應用需求及傳輸效能的關係式，藉此關係式可得知對應用最佳化的元件所需特性。我們更提供了一些簡單測試無線感測平台性能的方法還有一套依據應用需求的偏好程度來計算整體效益的公式，使用者可以藉此得到無線感測平台的效能。
　　實驗中，我們從上述的方法實際設計了類比輸出以及數位輸出的無線感測器介面，並利用數位訊號處理來達到應用需求的精準度和高取樣頻率。
　　我們希望這些方法能幫助設計者更有效且更迅速地設計無線感測介面平台，也幫助設計者或使用者從而選擇最適宜的無線感測平台。

關鍵字

無線網路 ； 介面

並列摘要

Wireless sensor networks are being considered in a wide range of applications, from environmental monitoring and industrial monitoring to health care management and home use. Different sensing devices and sensor platforms have been developed to date. One of the most important design problems is how to design an interface for a wireless sensor platform. The interface between the microcontroller and the sensing devices directly affect the performance, power usage, and data accuracy of a sensor platform.
In this thesis, we categorize the sensing devices and propose a methodology for systematic selection of the interface for cross-layer optimization. Sensing devices are categorized based on their output type, including analog, digital, capacitive, and high-level protocol types. We derive formulas for evaluation and estimation of sensor platforms implemented with alternative choices of interfaces. We demonstrate this methodology with case studies of a real-world sensing platform by comparing analog and digital alternatives of sensing devices. We also use digital signal post-processing as a case study for evaluating the accuracy and high sampling rate as required by the application.

並列關鍵字

wireless sensor ； interface

參考文獻

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