Effect in range difference position estimation due to stations´ position errors

This work addresses the subject of systematic errors caused by using incorrect coordinates for the sites where the stations are located in a three-dimensional aircraft position estimation system, composed of one transmitter/receiver and three receiving stations. The differences in the aircraft ranges from the receiving stations are used to derive the position estimate. A general analytic expression is developed to assess the error resulting from using erroneous coordinates for the receivers location. Evaluation has been performed for certain representative conditions