Accession Number : ADA118907

Title :   The Near Field Radiation Patterns of a Spheroid-Mounted Antenna.

Descriptive Note : Quarterly rept. 29 Feb 79-29 May 80,


Personal Author(s) : Chung,H ; Burnside,W D ; Wang,N

PDF Url : ADA118907

Report Date : Nov 1980

Pagination or Media Count : 64

Abstract : An efficient numerical solution for the high frequency near field radiation patterns of a spheriod-mounted antenna is investigated. The Geometrical Theory of diffraction is the basic approach applied here. The ray analysis in the lit region is straightforward; whereas, the geodesic paths on the surface dictate whether the shadow region solution is practical to obtain or not. Previous attempts employing calculus of variations or tensor analysis were too complicated to use. Cylinder and cone perturbation methods are presented to simulate the geodesic paths on a spheroid, which in turn can be used to model an aircraft or missile fuselage. The geodesic paths are then efficiently solved via a numerical approach, in that a cylinder and cone are developed surfaces. This study has presented a very useful solution in approximating the geodesic paths on a spheroid, and predicting the high frequency near field radiation patterns for spheroid-mounted antennas. Using this perturbation approach one can extend this technique to solve for the geodesic paths on more complex convex surfaces. (Author)

Descriptors :   *Antenna radiation patterns, Near field, Antenna configurations, Numerical methods and procedures, Perturbation theory, Diffraction analysis

Subject Categories : Electrical and Electronic Equipment
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE