Radio Signal Source Position from Measured Azimuths

Abstract

The determination of moving object position is quite frequent task of armed forces. There are several techniques which use active or passive systems. The passive systems are based on capture, identification and analysis of any radio signal emitted by fast moving object (airplane, rocket etc.). The position of object can be determinate from this information. One possibility how to determinate the object position is a usage the measured geodetic azimuths of the moving object from several mobile devices (initial points). The principles of spherical trigonometry and geodesy are applied. The employed solution comprises the following key steps: calculation of azimuths and the connecting line of the initial points, calculation of unknown distances to the target, determination of geographic coordinates of the target, transformation of geographic coordinates into planar right-angled ones in the projected coordinate system. The above described technique was tested in the area of the Europe and final results and position differences were evaluated. Several recommendations for effective usage of described technique were done with respect of results of passed tests.