作為一種短距離的點對點無線通信技術，藍牙低功耗（BLE）受到廣泛關注。透過設備發現發現鄰近裝置，可支持各種物聯網（IoT）的應用。顯然，設備發現有著至關重要的作用，在物聯網設備中發現的設備數量與能源消耗之間的權衡。本文提出的智能設備發現機制，sDiscovery，自適應地調整掃描窗口，掃描間隔根據環境的現狀。特別是，我們利用發現是否有重複的裝置，以確保周圍環境的狀態變化頻繁。可對物聯網設備的掃描窗口和掃描間隔進行相應的調整。模擬結果表示，sDiscovery在省電方面優於現有的解決方案和常規的機制。此外，通過TI CC2540開發板實現協議的原型，並利用實驗驗證了模擬模型的正確性。我們的模擬結果表示，與常規的發現機制相比，sDiscovery可以節省約百分之74的功耗並僅遺失少數的發現數量。

As a short-range and peer-to-peer wireless communication technology, Bluetooth low energy (BLE) receives lots of attentions recently. By enabling discover devices in the proximity, BLE could support various mobile Internet of Things (IoT) applications. Obviously, device discovery plays an essential role on the trade-off between number of devices discovered and energy consumption for a mobile IoT device. This paper subsequently proposes a smart device discovery mechanism, sDiscovery, to adaptively adjust scan window and scan interval according to the current status of the environment. In particular, we leverage the number of peers discovered more than once to make sure if the status of environment changes frequently. The scan window and scan interval for a mobile IoT device could be regulated accordingly. The simulation results show that sDiscovery outperforms the existing solution and conventional BLE mechanism from the perspective of power saving. Moreover, we verify the correctness of simulation model through experiments in TI CC2540 development board, where a prototype of the protocol is implemented. Our simulation results demonstrate that compared with conventional BLE discovery scheme, sDiscovery can save around 74 percent energy by paying the price of discovering a fewer number of peers.

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