Passive localization using propagation models
Passive ranging using propagation models can be effected in two different ways: forward modelingand direct inversion. The forward-modeling method performs an exhaustive recomputation of the fieldover a set of assumed source locations and seeks the best match to the measured data. The directinversion method inverts a set of linear equations constituted by the normal mode model. An overviewof these two approaches is given along with a summary of studies performed to date. This is followedby the presentation of a maximum-likelihood algorithm for the direct inversion method. A discussion ofthe merits and weaknesses of each method is given. Also, an appendix which discusses some general aspects of the inverse problem is included.
Sullivan, Edward J.