Using parts from previous wi-fi antennas I have built, I attempt to create a monster antenna, yet only to wind up with an ordinary cantenna wave-guide with funnel attachement.
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Signing UpStep 1: Harebrained idea
I saw some info on how to make a Patch Style antenna for 802.11 networks.
I thought if one director was good, maybe more would be better. So I used the dimensions from the patch antenna to determine an aperture for a conical wave-guide, this so that I could use my fire-extinguisher based cantenna as a wave-guide feed. The patch directions recommend going to a store like a dollar store for a lid. I happened to find some cutting boards that were just big enough and bought one to test in the microwave. Passing that test, I purchased more and decided to use 3/4" pvc tubing as a frame.
W1GHZ
This is the page where you can find the latest version of the waveguide calculator, which I used to find the right length for this cone, based on the diameter of my existing cantenna waveguide, and on the 242mm diameter directors. This software indicated a possible gain of 13 Db. If it came close to that is still unknown as I still need to learn how to measure that. This is also where I can learn how to measure my results, if I would just spend more time there!
Seeing as I'm throwing in software links - Delta Cad is what I use to draw my designs. However, I took several years of drafting classes and what little of that I can still remember is not included in the help section that comes with Delta Cad, sorry.
I thought if one director was good, maybe more would be better. So I used the dimensions from the patch antenna to determine an aperture for a conical wave-guide, this so that I could use my fire-extinguisher based cantenna as a wave-guide feed. The patch directions recommend going to a store like a dollar store for a lid. I happened to find some cutting boards that were just big enough and bought one to test in the microwave. Passing that test, I purchased more and decided to use 3/4" pvc tubing as a frame.
W1GHZ
This is the page where you can find the latest version of the waveguide calculator, which I used to find the right length for this cone, based on the diameter of my existing cantenna waveguide, and on the 242mm diameter directors. This software indicated a possible gain of 13 Db. If it came close to that is still unknown as I still need to learn how to measure that. This is also where I can learn how to measure my results, if I would just spend more time there!
Seeing as I'm throwing in software links - Delta Cad is what I use to draw my designs. However, I took several years of drafting classes and what little of that I can still remember is not included in the help section that comes with Delta Cad, sorry.
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By magnetic suspension, I'm assuming you will attach magnets to the bottle, or something.
But if you want to spin the bottle using a stream of directed air, why not just use the air itself as the suspension?
And just putting the WiFi transmitting unit next to the bottle may not be enough. If there's any effect at all, I would expect it to be affected by the precise distance between bottle and WiFi antenna, orientation of WiFi antenna, method of applying the aluminum tape - pattern of seams, capacitance effects from layers of aluminum & tape adhesive, if magnets are involved what about any possibility of eddy currents being generated inside of the aluminum - which goes back to the pattern of the tapes orientation, I would be tempted to try coating the inside of the bottle with a thin coating of paint and then aluminum powder such as Stop Leak for radiators, and if the bottle did anything, there will still be the amount of energy being transmitted by the WiFi antenna in directions away from the bottle so if you are thinking of generating a kind of magnetic containment field extending beyond the bottle then good luck! You will need some very serious measuring equipment to tell what's not working right. I think you should consider how to control the bottles rpm's very precisely. And try to figure out a method of detecting eddy currents. You might be doing nothing more than creating a very bad power generator at gigahertz frequencies. But it sounds like fascinating research. I would recommend using a very directional WiFi antenna. Maybe that trough should be the open end to a circular waveguide? Or a open-faced resonance chamber that faces towards the bottle's side, and the WiFi radiating element inside that?
Also, to the resonance chamber, a satellite dish would probable work well, with the Wi-fi source at some point behind the focal point, and the spinning bottle in the middle of the focal point, so it would spread out the signal that hits it, assuming it would actually work in that way.
http://www.w1ghz.org/antbook/contents.htm - this is a good place to start refreshing your design approach.
there are a few 'ibles on here that show how to make a Tesla disk turbine from some old hard drive platters, so it wouldn't be too out of reach, and I was thinking that the turbine would be better than a air powered die grinder since it would use a decent bit less air, since I wouldn't want to invest in a huge air compressor, that way, the air tank could be continually filled. I suppose a Dremel would work, but a corded one would be necessary for the higher power and endless power supply.
I would also assume the magnetic levitation would keep it balanced and rather centered, but I could be wrong
A magnetic suspension is a very flexible sort of thing, so any kind of oscillation will build up very quickly into an unbalanced condition. I suspect that designers of high-speed maglev trains will have some interesting points to say about this. Try to imagine a maglev running a continuous loop at 230 miles per hour. Which is approximately the surface speed of the bottle at 20,000 rpm's. This only means that you need a very well thought-out arrangement for your magnets. Placing magnets on, or inside the bottle will probable stretch the diameter of the plastic at very high speeds due to the mass of the magnets acting under centrifugal force.
This kind of speed is one of the reasons why Tesla never got anywhere with his turbine design. Using the materials available back then, the disks kept shattering at any useful speed unless they were a very small diameter. But then the total horsepower was too low to be of any value for what he wanted to do. A scrapped hard drive disk is engineered to spin at a high speed. But they are rated for a speed that wont flutter at a microscopic level, you can actually run them much faster if all you want is to not shatter.
I would highly recommend that you skip all of the WiFi stuff and focus on simply spinning a bottle. And try to control the speed through as wide a range as possible. Maybe you shouldn't be running above 1000? You don't know yet what to expect from a spinning cylinder placed inside of a 2.4 gigahertz EM field.
sorry for that..
its very hard for me to do the conetenna..
we have a group project..and we choose conetenna for our poject..
You could go to my profile and send a message directly to me about this group project.
What the Pringles tube does is the exact same thing as what the fire-extinguisher tube in this instructable is doing. Only the dimensions are different, and so the performance will be different.
You can use a Pringles tube along with a matching cone to improve the performance over just the Pringles tube alone.
The cone is an add-on. You should just get the tube to work first and try changing how it's made several times before going to the next part of designing a cone.
I think the cone amplyfies the signal, the signal is a wave in the air, if you can do an aluminium cone, i think it could be better. Try to put the cone near your ear, i think that the wave (wifi signal) can be the same as the sound waves....
Nice, I will do somthing like that.
http://www.usbwifi.orconhosting.net.nz/
http://www.aircrack-ng.org/doku.php?id=es:cantenna_directional_antenna_with_gain
By the way, this used an aluminum cone. It's a composite style construction. The plastic cone is just a form to hold the aluminum in the right shape.
Yeah, putting a cone to your ear will help you hear more of a sound. But that still is not amplifying the sound, only reducing the amount lost. For the WiFi signal, most of that will not enter the antenna. A cone will help reduce that loss.
Otherwise, you will have to use the google same as me.
en.wikipedia.org/wiki/Antenna_measurement
I might try a more practical measurement. Just measure your connection speed by searching google for 'speed test' and using one of those results for a server that's close to where you are.
Do the same test using the bare adapter, and again with the waveguide
Take the result for the bare adapter and write that down on a sheet of paper. Double that number and write that down underneath the first number. Keep doing that until you get a number that is bigger than what you got using the waveguide. Count how many times you had to double the first number without going past the waveguide result, and multiply that by 3 (every 3 dB is a doubling of power). Assume that your adapter is 5 dB by itself and add that to the result (you could of course try to find the actual dB of your adapter). This will be a number of decibels that you will not be able to use in comparison to anyone elses antennas. This measurement will be only for your own use, to see how well you have done. If you build another antenna you can use this approach to see what change there may be in connection performance.
you know that antenna is a 5 of the type of wireless antenna !
It is a DISH is a type of antenna that you use .
Additional it is commonly use in towers or communicating towers
and also for wifi
As for determining the actual gain in decibels, I wouldn't worry too much about that. I think the shape of the antenna's radiating pattern is more important than what it's numbers are.
and the waveguide of it?
I would highly recommend that you rotate your antenna and check your signal level yourself, as the conditions you will experience may be different from what I have.
I believe that the adapter has a linear radiation pattern from itself, so a circular type of polarization is not going to happen here. That means that the circular cross-sectional shape of this waveguide is likely not the best idea, but is just a construction shortcut. A rectangular cross-section with the right ratio between long and short sides would be better.
is plastic good for getting signal?
y u used plastic?instead aluminum alone
what kind of aluminum r u using?
On the other hand, the aluminum works very well at making the signal go where you want. In this case, what I used was some really thin Chinese made foil wrap. They didn't put a steel cutter on the carton, the foil is so easy to rip that just some cardboard teeth will cut it straight across.
One problem with using this foil wrap is that it wont keep it's shape if you even so much as touch the stuff, and the cone shape the foil is patterned after is supposed to be a precision device.
Now what the plastic does, is it makes for a very nice rigid shape that holds the foil in a fair approximation of the cone it needs to be. As a plus, the plastic is transparent at that frequency and won't get in the way of the signal. I tested this by putting some of the plastic by itself in my microwave and it did not get hot. (that means it did not absorb any of the energy, or 'block' it - also microwave ovens use almost the exact same frequency as Wi-Fi)
what are the specs of it??
what connector you use from the conetenna to your pc sir? do it need some usb wifi adapter?
The cutting kit attaches to my Dremel by unscrewing the accessory collar which is right behind the bit holding part of the Dremel, first chucking the spiral-cutting bit onto the Dremel, and then screwing on the accessory - which acts to control the cutting depth and also keeps the cutting bit aligned perpendicular to the plastic panel that I'm cutting here. The cutting bit will drill it's way through the plastic, and then cut sideways any which way you want it to by pushing on the accessory base.
By compass, I mean a drafting compass to first draw a circle. The circle will be the guide-line I follow with the Dremel to cut a circular hole. You could instead try using the can to trace a circle onto the plastic. (place one end of the can at the center of the plastic disk, trace around edge of can to leave a line on the plastic just slightly bigger than the can...) But I would recommend using a compass because you can find the exact center of the disk and then put the steel pointed end of the drafting compass on that point, this way the circle you draw will also be exactly centered on the disk. The hard part is following the line with the Dremel!
If I were to trace a cutting line without a compass, I would place the can where the hole should go, then use a ruler to adjust the position of the can from side to side, and then from up to down so the distance measured on the ruler is the same from the edge of the can to the edge of the disk in every direction.
I could do this without a ruler, if necessary, by using a strip of paper as an improvised ruler and make a mark at the edge of the disk in one direction, then see where that mark winds up at in the exact opposite direction - eg other side of the can.
Dishing the Conetenna would require a very big dish. As I have become used to carrying my Conetenna around in my car, I would like to keep the size under control. I might just go the conventional route and get a proper wifi card with pigtail and make the radiating elements of a new antenna.
I like the looks of this: http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=13491
Which uses wood what makes it simpeler. But then it's not really for outdoor use, but that doesn't matter because I only want to use it as a directional antenna at the university. To bad that the link of the original designer is dead so I can't show you that (http://www.andrewhakman.dhs.org/yagi). Fortunately for me I have saved the pages in the days that it still worked.
The original designer took a commerial wifi yagi and took it apart and measured everything up. So much for diy... it's just a copy of a commerial one. The original one used a plexiglass rod as a base, that would also be nice. Weather resistant and still easier to work with than metal.
check this my first instructable here ; there at the end are also 4 U two interesting links :-))
OK...here's an idea, but I have no idea if it would work.
At my local hardware store,they have plastic spools that when empty,they throw away. So I'm thinking, would they not work as well or better?
if you needed something as long as what you show above, maybe take 2-4 empty reels & fasten them together....you want a larger opening at the front? use a large one in front followed by a smaller one.
Keep in mind, I'm not an Einstein, & I have no idea if this would even work...
I think it's a cool idea that ppl like you can make some really amazing things out of what others take for granted or whatever "junk" is laying around. 8)
Here is a great tool for playing with 802.11 networks, it's free.. http://www.netstumbler.com/downloads/ and you can see your before and after gains..