Indoor and Outdoor Seamless Localization Method Based on GNSS and WLAN

Localization technology has been widely applied in various fields such as military investigation, natural disaster prevention, address search, and travel route planning. In order to guarantee the coverage range and localization performance of localization technology in both indoor and outdoor environments, research on indoor and outdoor seamless localization using global navigation satellite system (GNSS) and wireless local area network (WLAN) has attracted lots of attention. In this paper, a seamless localization method based on GNSS and WLAN is proposed. The method is able to switch smoothly from GNSS to WLAN localization in indoor and outdoor environments and outperforms either the GNSS localization or WLAN trilateration localization.