Recently, with the rapid advancement in information and communication technology, RTLS(Real time location system) using radio waves or RSS(received signal strength) has been studied in a variety of fields such as security, safety and logistics. Representative technology of GPS, it is difficult to measure a precise localization due to low permeability of the signal by obstacles such as walls, buildings. One of them, a ship which consists of steel structure has high reception rate but causes significant ranging error due to the reflection of radio waves.
In order to adapt the localization in a ship, this paper presents to analyze a variety of localization method and propose RTLS algorithms based on the fusion of WLAN(Wireless LAN) and UWB(Ultra wide-band) in the corridor of ship.
The proposed algorithm using modified Fingerprint reduces the size of radio map and the number of UWB fixed nodes. Because the variation of AP signal as compared with building is not large enough, radio map of modified Fingerprint is small and widely collected by mobile phone. also, In order to reduce location measurement errors, The estimated position was calibrated by the standard deviation.
The experimental results show that the accuracy of localization is maintained, and the number of nodes and the computational complexity are reduced to 50% and 60% compared to conventional fingerprint in the corridor by using proposed algorithm.