A Modified Proportional Navigation Guidance for Range Estimation

In this paper, after defining pure proportional navigation guidance in the 3-dimensional state from a new point of view, range estimation for passive homing missiles isexplained. Modeling has been performed by using line of sight coordinates with a particulardefinition. To obtain convergent estimates of those state variables involved particularly inrange channel and unavailable from IR trackers, nonlinear filters such as sequential U-Dextended Kalman filter and Unscented Kalman filter in modified spherical coordinatecombined with a modified proportional navigation guidance law are proposed. Simulationresults indicate that the proposed tracking filters in conjunction with the dual guidance laware able to provide the convergence of the range estimate for both maneuvering and nonmaneuveringtargets.