為因應物聯網(Internet of Things)蓬勃發展之趨勢，IEEE乃採用1GHz以下頻段，制訂IEEE 802.11ah標準，以實現低功耗、長距離之萬物互聯網路環境。為了提供物聯網中數量龐大節點之連網服務，IEEE 802.11ah的媒體存取控制則是搭配受限存取視窗（Restricted Access Window；RAW）機制。本論文乃針對使用IEEE 802.11ah提出的RAW機制可能會導致之耗能或網路效能不彰等問題，提出新的改良方案。實驗分析數據顯示，相較於RAW，我們提出的方法確實能有效改善耗電量與網路吞吐量。

In the upcoming IEEE 802.11ah standard, frequency bands below 1GHz are adopted for the achievement of lower power consumption and longer distance in response to the growing Internet of Things (IoT). By using the Restricted Access Window (RAW) mechanism, the IEEE 802.11ah is anticipated to be able to provide efficient usage of wireless bandwidth for huge amount of IoT devices. In this thesis, we propose a new method for the uplink and downlink slot allocations of the IEEE 802.11ah channel access. Experimental results show that our approach can achieve the lower power consumption and the higher network throughput when compared to existing RAW slot allocation mechanisms.

摘要 I
Abstract II
目次 III
圖目次 IV
表目次 V
Glossary VI
1、 緒論 7
1.1、 研究背景 8
1.2、 面臨問題 9
1.3、 研究目的 10
2、 相關研究 11
2.1、 IEEE 802.11ah 概要 12
2.1.1、 PHY 12
2.1.2、 MAC 12
2.2、 Use Case 19
2.3、 其他研究方法 20
3、 研究方法 21
3.1、 待解問題 22
3.2、 方法描述 24
3.3、 隱藏節點問題 25
3.4、 可行性評估 27
3.4.1、 耗能比較 27
3.4.2、 吞吐量比較 28
4、 實驗與分析 30
4.1、 環境與實驗設計 31
4.2、 實驗結果 33
4.2.1、 耗能量 33
4.2.2、 網路吞吐量 35
4.3、 RAW長度的影響 38
5、 結論與建議 45
參考文獻 46

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