Target Tracking Using Radar and Direction Finder

At the radar systems, traditional target tracking algorithms are based on the radar measurements termed as plots. In this paper we consider a plot as a vector, which contains measurements of azimuth angle, slant range and sometimes elevation angle. These data are quite sufficient to estimate the target position. Direction finder is a device, which measure only azimuth angle termed as bearing; bearings is considered as another imported source of information nonetheless traditional tracking algorithms based on the plots. This work presents the concept of uniform using plots and bearings as sources of information for tracking systems. Modifications of Kalman filter equations enabling the use bearings, for tracking are presented. The key idea includes the concept of a precision matrix being the reverse of a covariance matrix. The bearing may be used as a plot, in which the precision of distance measurement is zero. Thus a bearing is a plot defined in a singular precision matrix. The precision matrix easily enables the description of this type of measurement. In addition estimators' formulae using the precision matrix are much simpler.