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Backfire WiFi Antenna

Backfire Antenna is a very small antenna with extremely good gain. With a half power beamwidth of 32 degrees, the backfire is a highly directional 2.4 GHz antenna to put the signal exactly where you want it. The backfire is convenient because of its small size. The 17 dB of gain is incredible for an antenna this size. Installation is very simple with the included mounting bracket. The backfire is weather-proof because of it's ABS radome, which covers the radiating element.

If you have limited space but still need a high gain antenna, the Backfire is the perfect antenna for you WiFi installation. For full specifications, please see datasheet below.

 

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The backfire antenna principle is a highly effective technique for improving the pattern characteristics of an antenna. When the space between the reflectors(from 0.5 *lambda to lambda) the backfire antenna called short backfire antenna(SBFA) and its called long backfire antenna(LBFA) when the space between reflectors greater than the wave length (lambda ).

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,,,it is a simple dipole short-circuited with an adaptation loop...!!!

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,,,,yes,this is a combination of corrugated horn-antenna and short backfire antenna...!!!

 

,,,this it"s corrugated horn...

 

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Jomy ,. which dipole PERFORMs better...?

did you try Circular Polarization...?

Look what happens when i add a RIM to the Secondary Reflector...

archery.JPG 

PD: What tool you use for CAPTURING the animation to GIF...? (for various frecuencies)

Edited by clanon
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Clanon, you can create circular polarization by using cross dipoles. like crossed dipole or crossed bow tie antenna. moreover you can create CP by truncating stubing and sloting in a patch.You can get a circular polarisation with a planar spiral antenna which has the same circuit modelling of a dipole but with CP.

 For 2.4GHz sbf-antenna is very large in diameter(580mm)...!!!

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On 10/14/2016 at 5:05 PM, Admin said:

 

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Admin, what is the aim of 2 dipoles, and 2 ports? Can it run with one?

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,,,, yes, only one port can be run but the gain is smaller ... !!!

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That top antenna would almost certainly be two antennas
modified into one. I imagine it is NOT very efficient or
effective receiving signals 180 degrees apart. i have come
up with a much better alternative to receive UHF signals
180 degrees apart. It is much more efficient than removing
the reflector.

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when i thinked about this antenna, it was single feed point in my imagination ))

so when 2 dipoles connected to 1 feed point it is gonna work like primitive array

 

 

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which kind of connection for this dipoles?

there are options:

 

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p.s. it looks +2db even if compare with commercially available 2.4 GHz backfire antenna same sizes

SO if you got SWR-meter and lot of free time - try to construct it :)

because this 2dipoles feed system is perfect for backfire antennas

 

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...only 14 dbi...(there are LOTS of plannars with that and more...(smaller , size and volume...) Nice dipole though...to use on a bigger DISH

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3 minutes ago, clanon said:

...only 14 dbi...(there are LOTS of plannars with that and more...(smaller , size and volume...) Nice dipole though...to use on a bigger DISH

well, looks at the picture in first post. 17DBI - twice better

that is why i so surprised that no one still constructed it :)

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The more dielectrics the more LOSSes...(efficiency is 65 % 70 at the best cases...) illumination losses , spillover...

These antennas...without VOLUME and Diameter...never pass the 17 18 dbi...and most are a BITCH to point out...(But good for a POINT to POINT)

Edited by clanon

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PENCIL BEAM (hard to point it out)

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Edited by clanon

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1 hour ago, clanon said:

The more dielectrics the more LOSSes...(efficiency is 65 % 70 at the best cases...) illumination losses , spillover...

These antennas...without VOLUME and Diameter...never pass the 17 18 dbi...and most are a BITCH to point out...(But good for a POINT to POINT)

there is no dielectric in this backfire antenna

only radome

 

and about 16-17dbi for such compact antenna...i am not sure and that is why i asked someone with SWR-meter build it and compare with reference 17dbi yagi or panel :)

 

this double dipole with single feed is PERFECT exactly for Backfire antennas...there is chance that this antenna in real life may perfome even better than _some_ simulators show.

but yes,16-17dbi is DEFFINATLY upper limit for this sizes

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37 minutes ago, devton said:

you will never know until build one :)

Haven't  got "good" experiences with all parabolas y tried...(regular and offsets) Hard to point and adjust Feed...

Wire (colineals) and Patch worked (better for me)

If i need long range (more than 10km) i would go for the GRIDs (1m by 0.6) 24db or so...

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Edited by clanon

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