With 13dB of gain and a big 120 degree beamwidth, this could be one of your best homemade WIFi antenna. It also has a strong front / rear insolation.
In WiFi communications, antennas with semicircular radiation diagram in horizontal plane are often needed. Antennas with circular radiation diagram may have gain as high as it is possible to narrow its vertical radiation diagram. That’s where antennas with radiation dipoles aligned vertically are used. When circular diagram is needed, and vertical polarization is used, that alignment of half-wave dipoles can be carried out according to the principle of the famous Franklin’s antenna.
Open half wave dipol fed in the middle, is extended on both sides with one continuous conductor, which is, every half wavelengths, folded in quarter-wave short-circuited part of symmetrical two wire line. In this way, proper phasing of the half wave dipoles are performed. This kind of wire antenna has been used, mainly in horizontal polarization, from the very beginnings of radio on medium and short waves and is known as Franklin’s antenna, after its author.
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