Boost your router/Hi-Fi Signal Strength

This really does work. I made two of them and aimed at upstairs room, and it make a big impact on signal strength. Follow the simple directions here. This has been around for a long time, but it really does work.

Very good, I'll give it a try .

My AP is one of those newfangled ones without an external antenna. I'd probably have to put a reflector on the whole thing.

Oh well, I have a small home so it works fine as it's now.

As a ham and the little I understand about antenna theory I can tell you that this does not work. Here are the reasons:

1. The antenna on the router (which has a 2.1 dBi gain already since it is a half-wave dipole is partially behind the "dish." This kill much if all of the gain and makes the dish somewhat transparent.
2. Regular paper is not that reflective to RF I could ask the microwave guys at the radio club, but I doubt that the paper reflects the signal, this makes the dish opaque to the RF causing loss in one direction but not gain. You need foil to do this properly. Luckily combined with number 1 above the loss is a lot lower.
3. The design makes no attempt to focus the signal. Without 1 and 2 above the net effect would probably be loss, but combined with 1 and 2 above the net effect would probably be nil with a geeky look.

This post is not to make you not want to learn antenna theory and design your own antenna. In fact if you want to learn antenna theory just to prove me wrong on this in the case I am wrong, I encourage it. I encourage you to learn antenna theory anyway. Here are a few things to encourage you:

The 2.4 GHz band is a great playground for the unlicensed, you can have an effective radiated power of 4 watts referenced to an isotropic radiator. You can have up to one watt of transmitter power, but you must keep within the 4 watt EiRP rule. So with full legal transmitter power you can have 1 watt transmitter and a 6 dBi antenna and be legal. Just note that this does not account for coax losses. When dealing with microwave frequencies polarity does matter, you can lose up to 20 dB related to the other end with the opposite polarity (this does not come into power calculations). Note all rules are related to USA FCC regulations under 47CFR15.

Your first tip, when using a laptop lay your router antenna flat with the top pointing 90 degrees away from where your laptop will be. This could give you a net gain of up to 20 dB. Remember RF polarity is determined by the antenna system not any other part of the system.

jrmcferren said:

As a ham and the little I understand about antenna theory I can tell you that this does not work. Here are the reasons:

1. The antenna on the router (which has a 2.1 dBi gain already since it is a half-wave dipole is partially behind the "dish." This kill much if all of the gain and makes the dish somewhat transparent.
2. Regular paper is not that reflective to RF I could ask the microwave guys at the radio club, but I doubt that the paper reflects the signal, this makes the dish opaque to the RF causing loss in one direction but not gain. You need foil to do this properly. Luckily combined with number 1 above the loss is a lot lower.
3. The design makes no attempt to focus the signal. Without 1 and 2 above the net effect would probably be loss, but combined with 1 and 2 above the net effect would probably be nil with a geeky look.

This post is not to make you not want to learn antenna theory and design your own antenna. In fact if you want to learn antenna theory just to prove me wrong on this in the case I am wrong, I encourage it. I encourage you to learn antenna theory anyway. Here are a few things to encourage you:

The 2.4 GHz band is a great playground for the unlicensed, you can have an effective radiated power of 4 watts referenced to an isotropic radiator. You can have up to one watt of transmitter power, but you must keep within the 4 watt EiRP rule. So with full legal transmitter power you can have 1 watt transmitter and a 6 dBi antenna and be legal. Just note that this does not account for coax losses. When dealing with microwave frequencies polarity does matter, you can lose up to 20 dB related to the other end with the opposite polarity (this does not come into power calculations). Note all rules are related to USA FCC regulations under 47CFR15.

Your first tip, when using a laptop lay your router antenna flat with the top pointing 90 degrees away from where your laptop will be. This could give you a net gain of up to 20 dB. Remember RF polarity is determined by the antenna system not any other part of the system.

Click to expand...

The instructions state to glue foil to the back of the paper.

One could cut the bracket piece corner to corner of the parabola it forms (and cut off that ugly logo!) to get the antenna out from behind the paper.

I could be wrong but....

The rectangle is the reflector. The shield shaped thing is used to mount it on your antenna. The shield also deforms the rectangle into a rough parabola in two dimensions.

So if you put foil on the surface of the rectangle, and make the "shield" of a relatively RF transparent material, it should provide gain in one direction. The rectangle will be totally behind the antenna.


Daniel

man its been years since i saw that page ...that and the pringles cantenna :laughing: it is a free easy but with the cheap patch antennas available now i would get that instead but the foil would be fun to experiment with

If you happen to have certain versions of LinkSys WRT54G/GL/GS and WRTSL54GS wireless routers, you can load third party firmware that fixes all the LinkSys firmware bugs plus it allows you to do all sorts of advanced things, including turning up the transmitter power.

Simply turning up the transmitting power will NOT help you at all on the recieving end...

"Reflector"
This will not work... it will actually hurt your signal strenght for an omnidirectional antenna....
I am a ham and have studdied antenna theory substantially. I build and utilize alot of my own di-poles and wire antennas. If you would like i could easily spend 30min+ writing up a post with all the proper terminology facts and figures.....

Let me know if you guys want all this info and ill try to make it not make your brain hurt, like it did mine learing all this funn stuff.....

If any of you would trully like to understand how to make/buy good antennas for your wifi system pick up a copy of the A.R.R.L. antenna handbook... You will learn more about antennas then you will ever want to know.

Well I made one and installed it. Here is what I observed.

Without the reflector my signal strength was 47%.

When I install the reflector and point it in the direction of my laptop, I register a signal strength of 53%.

When I turn the reflector around, pointing the other way, my signal strength drops to 40%.

I am not sure how accurate these results are, but it seems to do something...

Tom

It works.

You don't need to print nothing. Just take a piece of foil and make it dish shape and put it behind you ant.

It's just a way to focus the signal.

Links to some usually Wifi antennas for long distance (relative) transmissions.

http://www.usbwifi.orconhosting.net.nz/

I wonder if they work?????? he says tongue-in-cheek

Here is why it wont work...(even though you see a slight improvement)
Putting a large piece of metal behind a radiating omnidirectional antenna without it being resonate on the intended frequency and a part of a counterpoise works in reverse...What you are essentially doing is blocking signals (interferance) from the rear of the recieving antenna and only allowing the ones from the desired direction...But in doing so you are also causing a high standing wave ratio wich reflects ALOT of the radiated power back into the full duplex transmitter (full duplex means it can transmit and recieve at the same time). Standing wave ratios higher than 2.0:1 can cause transmitters to heat up dramaticly, forcing them to work harder to radiate the same transmitted power, drasticaly shortening the lifespan of the "final".
Yes I know you do see a slight improvement over leaving it alone but.. you are actually loosing overall omnidirectional efficiency. A typical wifi antenna (most router antennas included) are a stacked array of 1/2 wave antennas to achieve gain. If you really want to boost your transmit and recieve of the system you can make a proper reflector. This would entail connecting the reflector to the negative (shield) side of the "f" connector on the back of the router. To make a parabolic antenna worth wile (loosing side&back recieve/transmit) the dish would have to be aprox 20.5" in diamiter, and the tranmitting/recieveing antenna would have to be centered in the parabolic dish perpendicular to the reflector....

This is a pain in the butt on a router this is why normal consumer routers use omnidirectioal antennas and commercial use large high gain omni antennas, dish antennas, and yagi's.

If it were me and i need alot of signal in all areas of the house as well as prolly most of the nieghborhood i would run a diamond g200 or a comet g-24. This would keep things omnidirectional allowing 360 degree signal propigation....If i wanted something extemely directional i would either build or buy a multi element yagi antenna......Or I could make and parabolic "coffee can" dish antenna for crazy gain...

Just my .02 cents
Do as you wish but i prefere to do it right
If any of you would like more info on how to build these antennas, or set them up please let me know and I'll drag out the ARRL antenna handbook and get the exact dimensions for you

thanks

The one I've always heard is the Coffee Cantenna - you cut a hole in the side of a coffee can way down next to the bottom of the can. Slide this hole onto your current wi-fi antenna, and point the open end of the can to your source/target :thumbsup:

Gotta love all the antennae "experts" who exclaim this could not work, including the 3rd response who didn't even check it out enough to realize the paper template is to give shape and stiffness to aluminum foil.

I am 100% sure that this works. Besides reading about it in this month's Maximum PC, watching a video discussion about it on TechTV, looking at several other websites that discuss it, my upstairs laptop through about 6 walls was only getting one bar signal strength, and repeated speedguide testing verified marginal connection. I saw this many years ago when they also talked about the Pringles can, which I dismissed.

So I make two of these stupid looking parabolic paper/aluminum foil antennae and stick them on the twin Linksys WRT54G antennae, angled at the laptop, went upstairs and suddenly saw 3-4 bars. I honestly could not believe it, and went back and forth like Silverfox, removing/replacing/re-angling, and right as rain, these lame antennae are worth trying. It is backed up with Speedguide.net bandwidth improvement.

What have you got to lose? A piece of paper and sheet of aluminum foil? I still don't believe it can work, but it does.

I didnt say it did not show a slight gain.....
I stated the obvious problems of creating a high swr issue with untunned reflectors....If it works for you and you like it then do it....but there are alot of beter ways out there to raise overall signal without shortening the routers transmitter lifespan......I could make a full wave dipole at about 10" long and it would perform beter....

compared to all the usuall junk that i see this one is one of the beter ones and a decent find lux, for a free, easy as all heck small return mod....now if yo ureally want to see improvement on this mod within these guidlines make the reflector round and shape it like a shallow bowl that will increas the effectiveness, and directiveness......but try putting the reflector at about 0.05dipole behind it (2.4g is about 5" wavelenth full dipole would be about 10" i.e. 1/2" or so) if you get the spacing right you will essencially double your gains and lower swr in the process......


starhalo
the coffe cantenna you thingking of actually isnt an antenna it is a horn reflector and it will do essencially the same thing as this tin foil mod....the coffee can antenna i was talking about is actually a tunned radiator with a parabolic reflector...looks like a satalite dish but it is extremely directional

This works, Any "reflector" will increase gain in a single direction. The trick is to put this on the "recieving" antenna My kids have wireless cards with external connectors on their desktops throughout the house and can connect from places that they could not before. I'm no expert but if it works :tinfoil:

S.MadPotato, an attack against a poster adds hostility to a thread, but nothing else. Re-wording your post to address the topic instead of the poster would be appreciated.

Edit: Nevermind. I removed the post.

I had also considered some of the 3rd party firmware resources such as www.polarcloud.com/tomato but most are not supporting my WRT54G Version 8 model, and cause heat issues as you crank up the "transmit power."

Obviously, there are more elaborate (& expensive) solutions which can work even better, but this was a simple post about a simple idea that has been around for a long time...and it worked amzingly well for my needs. It makes my router look like a two sail frigate! Anchors Away!

played with this myself today a little....

Lux as you stated it does work for your needs....
I did as it said and yes i say aprox .5-1 db gain from doinf this but unfortunately according to my antenna analizer it jumps the swr up pretty far(1.5 original to 2.1) but what fixed this was simply using the formula that i showed you for proper transmiter/reflector distance actually help out alot....brought it up to just over 1 db gain and an swr of 1.7 wich is acceptable.......

p.s. increasing the size of the reflector and making it more parabolic netted more gains with about the same swr


play on playa