Design Plan for 0 dBi VHF-FM Aircraft Communications Antenna System

摘要

This design plan, submitted in accordance with the requirements of contract DAAK80-79-C-0279, describes the design of a zero dBi aircraft antenna for operation in the VHF-FM band of 30 to 88 MHz. The plan is divided into six sections: 1. Introduction; 2. Location/Installation; 3. Element Design; 4. Matching Network; 5. Mechanical Configuration; and 6. Program Plan. The location of the antenna on the helicopter influences the pattern, vswr, and physical configuration of the antenna element. A monopole antenna, by itself, has an inherently omni-directional pattern. The airframe affects the pattern by scattering the radiation from the antenna. The strongest scatterers on the airframe are metal structures which are resonant at the operating frequency. The tail rotor of the OH-58A for example, is resonant at about 86 MHz.