Cramer-Rao Lower Bounds of Position Estimate Using Angle-only Measurements

2-D angle-only measurements (azimuth and elevation) from multiple sensors are often used to compute 3-D position of a target. However, unlike radars, the accuracy of the position solution here depends on the relative geometry of the location of the sensors wrt the object of interest. This paper presents the Cramer-Rao Lower Bounds (CRLB) of the error of position estimated using the measurements from multiple angle-only instruments. Variation of position estimation error along a given trajectory has been presented using this metric. Also, the paper demonstrates the utility of this metric to decide the deployment location of the sensors to achieve a given accuracy of position estimate.