Innovative improvements to High-Frequency Simulation Methods for Installed Antenna Performance

It is critically important to accurately predict radiation pattern, near fields and co-site coupling associated with antennas placed on electrically large airborne platforms, which can be addressed by high frequency techniques such as the uniform geometrical theory of diffraction (UTD). However, innovative improvements are needed for the development and application of these techniques due to challenges such as implementation of creeping wave mechanisms on faceted CAD models, identification of multiple order interactions and modeling of material treatments. Applied EM, Inc. has been developing a UTD based code, uCAST, to predict radiation pattern and coupling of antennas on electrically large aircraft platforms. During Phase I, some benchmark problems that can be specifically used to validate individual ray mechanisms implemented into the uCAST code have been determined. Radiation pattern data has been generated by the uCAST code for these benchmark problems. The data from the uCAST code has been validated against the MLFMM (multi-level fast multi-pole method) data from FEKO commercial software as well as the data from the UTD based NEWAIR code. Shortcomings of the existing capabilities and important missing interactions have been determined. During Phase II, the code will be enhanced based on the findings to yield better accuracy.