Indoor multi-resolution subarea localization based on received signal strength fingerprint

Fingerprint-based localization technology has been intensively studied for point localization in indoor environments. Subarea localization, which is to localize a mobile target into some subarea, is also a practical issue in indoor localization. In this paper, we propose the concept of multi-resolution subarea localization based on received signal strength fingerprinting technique. Different levels of subarea fingerprints are first obtained by constructing coverage range-based fingerprints, and by received signal mean values or probability distribution based fingerprints. We also propose two subarea localization schemes that consists of a two-step localization. At first, the radio coverage range fingerprints are used for localization, and when this method fails, we perform a deterministic-based or probabilistic-based fingerprint comparison to finally locate a mobile target. The field testing results show that the hit rate of the proposed schemes can achieve 0.95 or better in room level.