Boresight error in the conical scan method of autoboresighting a laser beam on a specular point-target.

While autoboresighting a laser beam on a specular point-target, the automatic tracking is set to the highest degree of precision by accurately estimating the beam position on the target. A serious degradation in the prediction of miss-distance in such autoboresightings (for example, by conical scan tracking) would arise if boresight error is encountered due to various sources of statistical fluctuations in the system. Typically, beam-intensity fluctuations (resulting from beam propagation through a turbulent atmospheric medium), imperfections in the trans-receive optical scanners, random variations in the nutation-drive signal, etc., are the main sources of boresight errors in the tracker system. Presently, for a conical scan tracker which uses a laser beam on a specular point-target, expressions for the mean and variance of boresight error are derived by considering various possible random parameters in the system concerned.