Independent component analysis approach to resolve the multi-source limitation of the nutating rising-sun reticle based optical trackers

Independent component analysis (ICA) is described for a number of signals f rom different sources and a number of receivers. When applied to nutating r ising-sun reticle optical trackers, ICA enables the discrimination of optic al sources with an appropriate number of detectors. The main contribution o f this paper is the conclusion that coherence between optical sources resul ts in a nonlinear ICA problem that becomes linear when the optical fields a re incoherent. It is shown that requirements necessary for the ICA theory t o work are fulfilled for both coherent and incoherent optical sources. More over, it is shown additionally that by the proper design of the optical tra cker the nonlinear model can be converted into linear one by simple linear bandpass filtering operation. Consequently, the multisource limitation of t he nutating rising-sun reticle based optical trackers can in principle be o vercome for both coherent and incoherent optical sources, (C) 2000 Elsevier Science B.V. All rights reserved.