Measurement Error Observer-Based IMM Filtering for Mobile Node Localization Using WLAN RSSI Measurement

This paper proposes a mobile node (MN) localization technique using received signal strength indicator (RSSI) data of wireless local area network. Range-domain measurement converted from the raw RSSI data can be used for localizing the MN. In indoor environments, however, the measurements may contain large errors caused by wall penetrating line-of sight (LOS) signals and non-LOS signals. The measurement errors cause large localization error. In this paper, a measurement error observer (MEO) is newly developed to mitigate the localization error. In addition, the MEO is integrated with an interacting multiple model (IMM) filter to take the flexible dynamic model of the MN into consideration. The purpose of the developed MEO-based IMM filter is to decouple the measurement errors from the localization and to adapt the filter for the flexible dynamics of the MN. Through comparative simulation and experimental tests, the performance of the developed filter is evaluated.