An Investigation of Some Slow-Wave Conical Log-Spiral and Helical Antennas
Abstract
The first part of the report is concerned with the characteristics of conical spiral antennas constructed with zig-zag, i.e., slow-wave geometry, arms. This construction permits a reduction in size of approximately 15 percent below that required for the conventional antenna. It also increases the pattern beamwidth and lowers the characteristic impedance. In part 2, a 2 1/4-turn monofilar conical helix, fed at the base of the cone against an inner metal core, was investigated. This small circumference (approximately 1/4 wavelength) antenna can be made to be an axial radiating structure, while the conventional helix of this size radiates a maximum of energy broadside to the antenna axis.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1973
- Accession Number
- AD0757913
Entities
People
- John D. Dyson
Organizations
- Massachusetts Institute of Technology