A hybrid numerical-UTD method for analyzing the problem of radiation by large finite phased antenna arrays on an even larger metallic platform (e.g. a tower on a naval ship) at high frequencies is presented in this paper. The problem is formulated in terms of a local array part and a full external platform interaction part. The local array problem can be formulated in terms of a governing integral equation (IE) or a finite elementboundary integral (FE-BI), which are solved numerically by using currently available fast and efficient algorithms; whereas the full external platform interaction formulation is based on the UTD ray technique which accounts for the presence of the electrically large platform. The coupling from the interior array region to the external platform region is through an aperture formed on the platform by the array geometry. Typical naval array-platform interactions based on this hybrid approach are examined in this paper.
