Home-Brew Antennae: Difference between revisions

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Metal sheeting can be used for the reflector, however, the ideal would be some sort of mesh metal, with holes smaller than 1/4 wavelength (<3cm), so that the antenna is not affected by wind as much.
Metal sheeting can be used for the reflector, however, the ideal would be some sort of mesh metal, with holes smaller than 1/4 wavelength (<3cm), so that the antenna is not affected by wind as much.



Revision as of 15:43, 18 November 2005

Omnidirectional Antennae

It is possible to make a homebrew omnidirectional antenna, as shown in the guides listed on Links#Antennae.

Directional Antennae

Cantenna

The instructions shown the websites listed on Links#Antennae were used ti build some cantennae as shown in the pictures:

Conical Feed element

Cantenna with bicycle spoke element


This File:Circular waveguide optimise.xls can be used to optimise the variables when building a cantenna.

Sectoral Antenna

A sectoral antenna provides the best of both worlds in terms of gain as well as beam-width and can be applied to many situations in mesh networking.

Turn an Omni into a Sector

The reflector designs shown, found at Freeantennas.com can be applied to a standard omni and will turn the omni into a sectoral antenna.

--- --- --- --- --- --- --- --- Metal sheeting can be used for the reflector, however, the ideal would be some sort of mesh metal, with holes smaller than 1/4 wavelength (<3cm), so that the antenna is not affected by wind as much.








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Simulation

NEC 2 was used to generate the simulated field pattern for a cantenna with the dimensions used in our first test cantenna.