- 學位論文
以FPGA設計製作居家照護無線感測網路系統
An FPGA based wireless sensor network for home health care application
摘要
本研究的目標是為建構無線生理感測網路平台，探討其居家看護應用之可行性。系統平台包含三項組成有無線生理感測節點、協調站與監控站。此系統平台以可程式化邏輯閘陣列晶片 (field-programmable gate array, FPGA) 為基礎，以之連接生理感測模組與無線傳輸模組，架構出無線生理感測節點做為擷取生理訊號；協調站除了包含FPGA之外，主要是以無線傳輸模組 (wireless LAN IEEE 802.11b/g) 為基底，接收無線生理感測節點訊號與傳送訊號至監控站；監控站的職司主要是接收協調站傳送過來之訊號並顯示之。此平台之通訊效能是本研究探討重點，測試項目包含資料傳送最大速率、訊號強度與傳輸距離和資料的穩定度。測試結果顯示，無線生理感測節點之量最大傳輸速率為46 KBytes/second，以此無線傳輸率測試天線增益(2和9 dBi)與距離的關係。於室外空曠空間測試結果，2-dBi天線之直線傳輸距離為40公尺，9-dBi天線之傳輸距離則為90公尺；室內空間測試，以垂直穿透樓層方式測試訊號衰減趨勢。結果顯示，2-dBi天線在樓層間穩定接收訊號，且訊號能夠穿透一層樓層(樓層間隔3.6 公尺)。無線感測節點在靜止的狀態傳送訊號至監控站，40公尺的測試距離之間或有或無鋼筋混凝土牆，結果顯示，在無阻礙牆的狀況下，40公尺的傳輸距離仍能維持完整的資料傳輸，然而，當有阻礙牆之時，完整的資料傳輸卻只能在30公尺之內的間距才得以實現。總結以上探討結果，本研究所研發之無線生理感測網路系統具有居家看護應用之潛能。
並列摘要
The purpose of this study is to establish a wireless sensor network platform for home health-care applications. The platform includes three types of system: wireless sensing nodes, coordination nodes and base stations. The development of the sensing and coordination nodes was based on field-programmable gate array (FPGA) chips. An FPGA chip controlled a sensing module to acquire physiological signals in digital form and then routed the acquired signals to a wireless LAN module (IEEE 802.11 b/g). Such an assembly is talled a wireless sensing node (WSN). Via the LAN module, the signals were usually transferred to a coordination node (CN) wirelessly. Analogous to the WSN, the CN was also equipped with an LAN module controlled by a FPGA chip. The main function of the CN is to relay the signals; thus no sensing module is included. The acquired signals were designed to display and store at the base station. In this study a computer was used to provide these functions. The developed system platform was evaluated with its data transmission rate and maximum transmission distance. The evaluation studies were carried out between a WSN and a base station. The fastest transmission rate that the WSN could achieve without missing data is 46 KBytes/second. Applying this transmission rate to the WSN’s with antennas eg 2-dBi and 9-dBi outdoor, the longest distances it could transfer data completely were 40 and 90 meters for the 2- and 9-dBi antennas, respectively. One of the indoor tests were performed between floors. The result indicates that data can be stably transferred across one-story floor (about 3.6 meters) for the WSN with 2-dBi antenna. The same WSN’s was configured with transmission rate of 10 KBytes/second to test the impact of concrete walls to the data transmission capability. The test results show that when a concrete wall blocked, the max transmission distance was reduced from 40 to 30 meters. In conclusion, the FPGA-based wireless sensor network platform developed in this study has a potential to be used in home health-care applications.