Passive range estimation by one camera using EKF and image processing

This paper proposes a passive range estimator by estimating the distance between a sensor or seeker from an object. The proposed approach works based on the changes of the object size due to the changes of object distance within a scene captures by the sensor. In this method we use an Extended Kalman Filter (EKF) to estimate the size of the object (physical dimension). The estimated size of the object and the information gathered from the sensed scene over time is used to passively estimate the object range. The results show more general and extended passive range estimation (by one camera) than other methods with less relative errors.