隨著無線區域網路(WLAN)的快速發展及室內環境中情境感知服務(Context-aware Service)的需求,造成近年來定位服務技術的蓬勃發展,在室外定位技術當中,最為普遍的便是全球定位系統(Global Positioning System, GPS),其主要是以接收環繞地球上空的衛星訊號達三顆以上即可進行定位,但在室內環境中,卻由於容易受到保持視線可及(Line-of-Sight, LOS)的限制造成無法定位成功,此時便須仰賴其它如運用無線區域網路的方式進行定位來提供定位服務(Location-Based Service, LBS)。 本研究將提出一個適用於室內、室外環境的定位服務系統,提供使用者無線訊號的圖形化呈現,得以快速了解所在區域無線網路資訊,並在室外環境以全球衛星定位系統(GPS)進行定位,在室內環境搭配無線訊號特徵定位方式(Radio Frequency Fingerprinting)的定位系統架構,目的在於讓使用者在由室外環境進入室內環境時,亦能夠持續提供定位服務,藉由提供適用於室外和室內環境的不中斷定位服務,提高使用者滿意度。
Positioning technology in wireless environment has emerged as a significant research topic recently due to the wide-spread deployment of WLAN and the demand of context-aware service in indoor buildings. Among the technologies of outdoor positioning systems, Global Positioning System (GPS) is considered the most popular one which identifies the location by receiving signals from at least three Medium Earth Orbit satellites. However, some other positioning methodology like positioning based on WLAN need to be developed for the Location-based Service since GPS tends to fail in positioning because of the limitation of Line-of-Sight (LOS). This study proposes a positioning service system which is suitable for indoor and outdoor environment, providing the visual graph of wireless signal to realize the information of WLAN and using the system architecture combined with GPS and Radio Frequency Fingerprinting based on WLAN. The objective of this position system is to increase satisfaction of user by providing continuous location service when entering indoor building from outdoor environment without interruption.