| Summary: | 碩士 === 國立虎尾科技大學 === 電機工程研究所 === 103 === 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.
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