Near-field electromagnetic modeling and analysis

For missile fuzing applications, the transmitting and receiving antennas on a missile are generally located in the near-field zone of the scattered field from the target encountered. In consequence, the radar return computation is complicated by the partial target illumination, nonuniform antenna patterns, target material coatings, and engine inlet returns. Existing near-field radar cross section (RCS) computation algorithms, such as NcPTD, are typically based on first-order high-frequency methods that do not account for multiple bounce, complex shadow effects and scattering from a cavity, such as an engine inlet or a sensor box. A successful missile/target engagement analysis must thus be conducted with accurate near-field target RCS information that includes effects attributable to multi-bounce, complex-shape shadowing, material coatings, antenna patterns, etc. This paper discusses techniques for solving near-field modeling problems in missile/target end-game scenarios.