Wi-Fi高吞吐量(throughput)且易部署的優點使其快速的發展，且常使用於無線區域網路(Wireless LAN, WLAN)中，但Wi-Fi除了通訊外，其實也可以基於不同的目的進行感測，例如手勢偵測、跌倒偵測、呼吸監測、室內定位等。Wi-Fi感測作為一項新穎的技術而吸引大家的關注，主要是利用Wi-Fi設備的通道狀態資訊(Channel State Information, CSI)來分析環境中的變化，進而達到感測的功能。目前市面上可以獲取CSI的工具中，大部分都為商用現貨(Commercial Off-The-Shelf, COTS)的設備，例如Intel 5300網路卡或Atheros Wi-Fi網路卡。Wi-Fi感測除了最重要的CSI之外，還需要其他實體層(Physical Layer, PHY layer)的資訊進行輔助，使感測結果更加準確，例如頻率偏移(frequency offset)、接收訊號強度(Received Signal Strength Indication, RSSI)、自動增益控制(Automatic Gain Control, AGC)等資訊。而商用設備並未提供這些資訊，也無法依照使用者需求進行修改。因此，本論文將設計一個適合應用於Wi-Fi感測的平台，解決了CSI相關資訊不足的問題，並且提供SIMO系統及天線擴充的功能。本論文以系統模組(System On Module, SOM)進行開發驗證，同時具備高效能且靈活的特性，更可以讓使用者依照自己的需求重新設計或開發新功能。

Wi-Fi networks are rapidly growing and are often used in Wireless LAN (WLAN) because of the advantages of high throughput and easy deployment. However, in addition to communication, Wi-Fi can also be used for different purposes of sensing, such as gesture recognition, fall detection, breathing monitoring, indoor localization, etc. Wi-Fi sensing attracts attention as an emerging technology. The principle of Wi-Fi sensing is to use the channel state information (CSI) of Wi-Fi devices to analyze the changes in the environment to achieve the sensing function. Currently, most of the tools available in the market to obtain CSI are Commercial Off-The-Shelf (COTS) devices, such as the Intel 5300 network interface card (NIC) or the Atheros Wi-Fi NICs. In addition to the most important CSI, Wi-Fi sensing also needs other physical layer information to make the sensing results more accurate, such as frequency offset, received signal strength indication (RSSI), automatic gain control (AGC) and other information. Commercial equipment does not provide this information and cannot be modified according to user needs. In this paper, we design a suitable platform for Wi-Fi sensing to solve the problem of insufficient CSI related information, and provide SIMO system and antenna expansion functions. This paper uses System-On-Module (SOM) for development and verification, which is high performance and flexible and allows users to redesign or develop new functions according to their needs.

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