Analyzing error propagation in range-based multihop sensor localization

Location information for sensors in wireless sensor networks (WSNs) is essential to many tasks. If sensors are mobile and are to be controlled to certain locations, localizability is indispensable. In a noisy environment, locations must be estimated, and the question of location error and its magnitude becomes important. Error is a function of the positioning and density of anchors in a WSN, and the error can propagate (i.e. increase) as sensors progressively more distant from anchors are localized. Understanding the semi-quantitative rules governing error propagation is quite helpful to designing WSNs and improving performances of localization systems. This paper deals with error propagation in 1-dimensional WSNs with noisy range measurements in terms of the Crame¿r-Rao lower bound. Factors influencing error propagation are investigated carefully, and a divide and conquer method is presented to analyze error propagation in WSNs.