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Pubic »porting burden for this collection of »ifomution a estimited to image 1 how per retponse. mchjimg the time for renewing ins the collection of Wormetion. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES)Mission Research Corporation 147 John Sims Parkway Valparaiso, FL 32580 SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES)AFOSR F49620-97-C-0022 SUPPLEMENTARY NOTES 12a. DISTRIBUTION AVAILABILITY STATEMENTApproved for Public Release; Distribution Unlimited. 12b. DISTRIBUTION CODE ABSTRACT (Maximum 200 words!The objective of this Phase II effort was to develop computational electrmagnetic (CEM) codes capable of modeling the radiation properties (pattern, input impedance, efficiency, and bandwidth) of conformal arrays printed on ferrite substrates or superstrates. The codes developed under this effort model inhomogeneous ferrites and dielectrics, non-planar surfaces, heterogeneous elements, complex feed mechanisms, and performance control devices such as shorting pins and lumped loads. The FE-BI codes (brick and tetrahedral elements) are combined by MRC via a graphical user interface (GUI) into a user-friendly code capable of modeling conformal antennas with ferrite sub-and superstrates recessed in planar surfaces. "Distribution is authorized to DoD agencies only, as the data is PROPRIETARY (see section 5.8 of DoD SBIR program solicitation 96.1)." Requests for release shall be referred to AFOSR/NM. Mission Research Corporation Proprietary Information Mission Research Proprietary Information ü APPENDIX A: USER'S MANUAL FOR THE MRC GRAPHICAL USER INTERFACE 39 APPENDIX B: USER'S MANUAL FOR FEMTETRA: A TETRAHEDRAL FE-BI CODE 50 APPENDIX C: USER'S MANUAL FOR MRJTETRA: MULTI-RESOLUTION FE-BI CODE 85 APPENDIX D: USER'S MANUAL FOR STRUCTURED 2D AND 3D MESHING 102 Mission Research Proprietary Information Mission Research Proprietary Informationiii List of Tables TABLED-1: FE CODE DEVELOPMENT STATUS 11 TABLE D Fenite materials have been suggested by the antenna community as a unique antenna loading material due to its tunable electrical properties. In particular, by appropriate application of a static magnetic bias field, a ferrite sample can exhibit a wide variety of electrical properties from nearly transparent to nearly opaque without mechanical intervention. Ferrites can also be magnetically tuned to preferentially interact with a given electromagnetic field polarization. For example, the sample can appear to be opaque to one polarization while transparent to the orthogonal polarization. Such properties can be exploited by antenna and low observable (LO) designers. This will be discussed in Section C. 1The finite element (FE) method (FEM) is uniquely suitable for analyzing the properties of ferrite materials since the FEM is typically formulated in the frequency domain, and hence can readily accommodate the frequency-dependent properties of ferrites. In addition, since the FEM requires no Green's function for the ferrite volume, its formulation and implementation is particularly straightforward. Also, since ...