智慧家庭中可信賴ZigBee網路之設計與實現

Design and Implementation of A Reliable ZigBee Network in Smart Home Systems

羅崇綸(Chung-Lun Lo)

指導教授 ： 鄭佳炘

國立虎尾科技大學/電機資訊學院/電機工程研究所/碩士(2015年)

摘要

近年來無線網路發展迅速，人們在智慧家庭中使用許多異質性質的網路設備，像是WLAN、ZigBee、藍芽…等，都是用於2.4GHz ISM頻段中，所以可能會有頻率相互干擾問題。本論文主要是建立可信賴的ZigBee網路，我們使用ZigBee RF4CE的頻率捷變技術，以跳頻方式掃描ZigBee 11~26的通道，並藉由Visual Basic人機介面查看目前有哪些是ZigBee網路與ZigBee協調者適合使用的通道。在佈署ZigBee網路節點位置時，利用封包接收率做為可信賴的參考依據，節點就能夠擺放到適合的位置，達到網路的穩定度。為了實際模擬在居家環境中的狀況，我們以WLAN與ZigBee的共存情況下做實驗分析，由此可得知ZigBee的頻率中有四個通道和WLAN正在使用的一個忙碌通道重疊，所以會造成嚴重的同頻干擾，封包接收率即會顯著的下降，ZigBee只要以跳頻的方式避開這些干擾的通道，或是將兩者擺放的距離長度拉長，調整AP的信標間隔和傳遞資料待傳指示訊息(Delivery Traffic Indication Message, DTIM)，都可增強ZigBee封包的接收率，達成可信賴的ZigBee網路。

關鍵字

ZigBee ； 封包接收率 ； 智慧家庭 ； 干擾影響

並列摘要

In recent years, the wireless networks have developed rapidly. People used many heterogeneous network equipments in the smart home. All of WLAN, ZigBee and Bluetooth etc., all are working in the 2.4GHz industrial scientific medical (ISM) band. Radio-frequency interference problems are existed when using these wireless networks at the same time. In this thesis, establishing a reliable ZigBee network is our goal. We utilized ZigBee RF4CE frequency agility technology to scan the channels of 11 to 26 in ZigBee with frequency hopping technique, and employed Visual Basic human machine interface to find the channels which are suitable for current ZigBee networks and the coordinator. We used the packet delivery ratio table as reliable reference that we could deploy the ZigBee network nodes to suitable positions and achieve the stability of network. In order to simulate the practical home environment, we experimented on the situation which is coexistence of WLAN and ZigBee. The experimental results showed four channels in ZigBee networks are overlap with the busy channel which is employed in WLAN. The packet delivery ratio would decrease significantly due to the co-channel frequency interference. ZigBee could use the frequency hopping technique to avoid these channels interfered by the channel overlapped. We also could make distance between ZigBee node and Wi-Fi access longer, adjusted access point of the beacon interval and Delivery Traffic Indication Message (DTIM) to avoid collisions. With the methods above all, we could enhance the packet delivery ratio of ZigBee to establish a reliable ZigBee network.

並列關鍵字

ZigBee ； Packet delivery ratio ； Smart home ； Interference

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