Modeling of Low-Gain Antennas on Aircraft using APATCH

Abstract

Radiation patterns for low-gain antennas such as those used for telemetry and collision avoidance systems were computed using the APATCH program. APATCH uses shooting and bouncing rays (SBR) to compute the radiation pattern for the antenna intalled on a scattering geometry. A built-in antenna model was used to represent a telemetry antenna and its accuracy verified by comparison with measurements and results from a method of moments patch code. Antenna patterns were computed for various locations on a Cessna 172 and an F-18 Hornet.