ABSTRACT
This chapter provides the derivation of the Cramer–Rao Lower Bound for received signal strength (RSS)-based localization and describes popular RSS-based positioning systems. It divides the popular RSS positioning systems into two categories: systems using RSS directly and systems using a fingerprint database for positioning. The process of driving around to collect an RSS fingerprint database is commonly referred to as war driving. Localization inside the human body has its own unique challenges, which has made this medium an interesting area of research for localization applications. Real-Time Location Services focuses on RSS fingerprints inside the buildings and Wi-Fi Positioning System mainly focuses on fingerprinting in the streets of a metropolitan area. An effective technique to reduce the cost of maintenance, expand the coverage, and increase the re-scanning intervals is to take advantage of user’s organic data to update the database.
