高可靠度的無線感測平台之實作與研究

Implementation and Studying of High-reliability Wireless Sensor Network

林幸男(Hsing-Nan Lin)

指導教授 ： 黃文增 ； 宋國明

國立臺北科技大學/電資學院/電資碩士班/碩士(2008年)

https://doi.org/10.6841/NTUT.2008.00571

摘要

無線感測網路應用於居家健康照護服務上已日益蓬勃發展，透過無線生理感測器量測病人之溫度、血壓、心電圖、心率變化與血氧濃度傳送至無線感測平台後，再將封包傳送給個人區域網路，完成系統的整體運作。因此，實作一套高可靠度的無線感測平台是無線感測網路核心技術之ㄧ。本論文的無線感測平台是以ZigBee作為無線個人區域網路的基礎，它建構在IEEE 802.15.4 的標準之上，具低功率消耗與高度網路定址能力的優點；除此之外，加上一個低功消耗的處理器就完成本平台的主體結構。一般，對於一個沒有設計數位系統經驗的電子工程師而言，若是直接將過去的設計法則帶入系統的設計中，則系統將會因為非理想因素而變的不穩定而不可靠。有鑑於此，我們針對目前設計數位系統的經驗與方法詳細的研究後，於本文中提出一套完整且具有高可靠度的數位硬體平台設計程序。這個設計流程可幫助電子工程師於電子電路設計階段時，藉由板級的信號完整性(Signal Integrity，簡稱SI)模擬軟體，分析信號在印刷電路板(Printed Circuit Board，PCB)上傳播的情形，進而找出較適當的PCB佈局規範，此仍是ODM廠商在PCB佈局技術上所追求的主要目標之ㄧ。
另外，在ZigBee的無線傳輸天線設計上，我們應用文獻中的公式與模擬軟體來分析曲折天線的特性變化與設計具最佳效能小尺寸的ZigBee曲折天線。然後，我們應用較佳PCB線路佈局規範與最佳效能的ZigBee曲折天線設計實作完成一個高穩定度的無線感測平台。從實測得知，系統傳送距離不但可穩定無誤的傳送超過24公尺而且不受電源變化影響。

關鍵字

無線感測網路 ； ZigBee ； 數位系統 ； 信號完整性 ； 佈局規範 ； 曲折天線

並列摘要

The Wireless Sensor Network (WSN) is a developing area today in the health-care service industry. For the sensor devices, physiological signals of the temperature, blood pressure, electrocardiogram (ECG), heart rate, and (Oxygen Saturation) SpO2 are measured from patients and then transmitted to the WSN system. Therefore, to implement a high-reliable hardware platform in a WSN system is one of major technologies. In this thesis, we uses ZigBee a wireless standard based on IEEE 802.15.4, which is a Wireless Personal Area Network (WPAN) with low power consumption and high addressing capability. Besides, a low power consumption MPU is designed in this study. Generally, traditional layout rulers cannot be met with the high requirements in the system for unstable signal in un-ideal factors. After studying and implementing the detailed research in our experience and methods, therefore, in this thesis, we propose and implement the hardware platforms with high reliability design in order to solve the study of the optimal layout rulers. During the design phase, our proposed design procedure can help us to analyze the signal propagation condition of the PCB (Printed Circuit Board) design by simulation software of the board level signal integrality. Moreover, the optimal parameters of layout rulers can be devised by this procedure. Using our proposed layout rulers to be applied the design of the MPU schematcis, designer can effectively build the reliable hardware platform, and then promote the system performance. Also, such layout technologies are the major pursuit goal of the ODM manufacturers overall on the PCB design.
Moreover, in the ZigBee wireless antenna design, we apply the formula in the literal and simulation software to analyse the characteristics of Serpentine-antenna and then design the small size ZigBee Serpentine-antenna with the optimal performance. Then, the better PCB layout rulers and optimal performance of ZigBee Serpentine-antenna design are employed here to realize our high-reliability hardware platform. From our experiments, we know that the system transmission distance not only can be over 24 meters without lost data but also is not affected by the power variation.

並列關鍵字

Wireless Sensor Network ； ZigBee ； Digital system ； Signal integrity ； Layout rulers ； Serpentine-Antenna

參考文獻

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