隨著物聯網(Internet of Things, IoT) 逐漸實現，現今物聯網專注於低功率廣域網路(Low-Power Wide-Area Network, LPWAN) 的設計。低功率廣域網路是一種為了因應物聯網裝置省電、長距離傳輸資料的需求所生，且可以用低位元率進行長距離通訊。儘管LoRa 技術本身已經明確，但如何在同一區域眾多終端設備的情況下有效地分配無線資源仍是一開放性的挑戰，於是本論文專注於設計出LoRa 優化傳輸參數組合之演算法。本論文將提出一種演算法，先將終端設備分群，利用傳輸參數的不同組合有不同資料率的特性來做分配比例的依據，藉由此分配比例並配合分群結果來指派傳輸參數組合，以達效能之優化。透過模擬結果可觀察出，本論文所提演算法在眾多終端設備的環境下能較相關文獻之方法有更佳效能之表現。

As the Internet of things (IoT) is gradually realized, the focus on IoT lies in the design of low-power wide-area networks (LPWANs) nowadays. LPWAN arises for power saving and long-range data transmission in IoT. It enables the long-range communication at a low bitrate. Despite the technology of LoRa is developed maturely, how to allocate radio resources efficiently among many end devices in the wide area is still an open issue. Target at this goal, this paper will propose an algorithm for LoRa to better system performance. First, end devices are clustered. Then, the fact that a different transmission ratio causes a different bitrate serves as the principle of allocation. By using this fact and the results of clustering, the system performance is optimized. Via simulations, we successfully show that our proposed algorithm outperforms the closely related algorithms in the literature in terms of the data extraction rate and throughput when more end devices are involved.

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