近年來，隨著無線網路的興起與普及，應用愈形廣泛。本篇論文主要闡述當語音透過無線區域網路傳輸時，受到同頻道干擾所造成服務品質降低，如封包遺失率提高、平均時基誤差增加等。
本研究使用IEEE 802.11b協定來傳輸語音，其操作頻帶為 2.4 GHz，但在此頻帶上亦有藍芽等其他系統而造成同頻道干擾問題。在此我們使用智慧型天線技術於同頻道干擾環境下使通話品質變好。
透過實驗及電腦模擬，可以得知使用智慧型天線技術於 IEEE 802.11b 系統後，可消除同頻道干擾，因此也可以使通話品質得到改善。

With the popularity of wireless network in recent years, applications are more and more extensively. This thesis elaborates the effect of service quality decrease such as packet loss rate and mean jitter increase caused by co-channel interference at voice transmission over wireless local area network.
Our research uses the IEEE 802.11b protocol for voice transmission, which operation frequency band is 2.4 GHz. However, other systems such as Bluetooth also utilize this frequency band and therefore cause the co-channel interference problem. We apply smart antenna technologies on the co-channel interference environment to make the voice quality better.
The experiment and computer simulation results show that it can eliminate the co-channel interference very well and therefore the performance of voice quality is improved by applying smart antenna technologies on IEEE 802.11b system.

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