# LONG-Range WiFi?



## TIGR (Feb 25, 2010)

A purely theoretical discussion. I think I better not/need not explain why I'm asking.



Would it be possible, in theory, for a person to connect to a wireless router two, even three miles away? With the consent of its owner, of course. Assume said router cannot be connected to any kind of high-performance antenna, so all the signal amplification is going to have to take place on the _other_ end.

Just for the sake of enhancing this purely theoretical discussion, let's say that one had a couple of old satellite dishes (DirectTV and WildBlue) available—could anything be rigged with their help?

Edit to add: what kind of latency would this introduce into the Internet connection? Assuming the wireless access point had 50ms latency already between it and the Internet, could one [theoretically] game on such a connection?

Remember: purely theoretical!


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## troyrae360 (Feb 25, 2010)

the answer is Yes, Opps missed the part where you cant connect to any kind of high preformance antenna


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## TIGR (Feb 25, 2010)

troyrae360 said:


> the answer is Yes, Opps missed the part where you cant connect to any kind of high preformance antenna



Does that mean the answer is no, this isn't possible after all?


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## angelkiller (Feb 25, 2010)

I'm certainly no expert, but I've been recently interested in long-range wifi.

When I first read your question, I thought of using an antenna on the router. And I don't mean those things that Linksys or D-Link sells, but I mean a bigger, custom antenna. Check this side out. Look under Long Range Wi-Fi under the Main menu. This page has some antennas as well.

But you said you can't do that so it's kinda moot. The other idea that came to me was using a high gain antenna on the client's end.

I can't give a definitive answer, but it seems that long range wifi is made possible by using the right antennas. Maybe this is helpful.


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## AphexDreamer (Feb 25, 2010)

What I've done is bought two Wireless repeaters and had them repeat one weak wireless signal twice. I was getting free internet from my Neighbor at 100% Signal Strength through out my whole house. 

That lasted a month and then we got internet.


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## TIGR (Feb 25, 2010)

Just to post as I learn, here's something I'm reading over now:
http://www.engadget.com/2005/11/15/how-to-build-a-wifi-biquad-dish-antenna/


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## TIGR (Feb 25, 2010)

AphexDreamer said:


> What I've done is bought two Wireless repeaters and had them repeat one weak wireless signal twice. I was getting free internet from my Neighbor at 100% Signal Strength through out my whole house.
> 
> That lasted a month and then we got internet.



Did you ever notice or check what kind of latency the repeaters added to the signal? Just curious about that, and about whether they add significant noise to the signal.

And that brings up another thought to add to the [purely theoretical] discussion.

Let's say Johnny, who is a very bad boy, has a friend whose neighbor has fast Internet and an unsecured Internet connection. Could Johnny set up a device in his friend's house that would connect to the neighbor's WiFi and then transmit an amplified signal to Johnny, who lives two or three miles away?

I of course do _not_ condone Johnny's naughtiness.


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## digibucc (Feb 25, 2010)

the critical rule with wireless networks to remember is that it's not enough to have a super-powered antennae - you need two of them.  it does no good to have point B strong enough to throw/read a signal 2 miles away - if point A can't sync. it's two way and without the other end there is no connection.

so unless you can physically install a directional antennae, then it's not really possible.



> Let's say Johnny, who is a very bad boy, has a friend whose neighbor has fast Internet and an unsecured Internet connection. Could Johnny set up a device in his friend's house that would connect to the neighbor's WiFi and then transmit an amplified signal to Johnny, who lives two or three miles away?


yes, now johnny is thinking. 2 miles is tough but possible.  it'd be expensive for the antennae, and mounting would be difficult.  any amount you can cut it down would be better.  

theoretically .  a router with a high power directional antennae and dd-wrt installed in wireless client/bridge mode , or even repeater.  client/bridge would be better, but both require a second router with the same high power antennae on the other end.


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## angelkiller (Feb 25, 2010)

TIGR said:


> Did you ever notice or check what kind of latency the repeaters added to the signal? Just curious about that, and about whether they add significant noise to the signal.


I would _think_ that repeaters don't hurt the signal very much. (Again, by no means an expert here) My reasoning is that many large places (hotels, schools, etc) use repeaters (IIRC) to make sure the whole building has wifi. So I would think that using a repeater is a practical thing.


TIGR said:


> And that brings up another thought to add to the [purely theoretical] discussion.
> 
> Let's say Johnny, who is a very bad boy, has a friend whose neighbor has fast Internet and an unsecured Internet connection. Could Johnny set up a device in his friend's house that would connect to the neighbor's WiFi and then transmit an amplified signal to Johnny, who lives two or three miles away?
> 
> I of course do _not_ condone Johnny's naughtiness.


I think with the correct antennas and conditions (few obstacles) that would be possible, but I'm pretty sure that that's illegal. (Not that I have an issue with that, just sayin) I actually _would_ condone  Johnny's naughtiness.


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## digibucc (Feb 25, 2010)

throwing the signal won't kill your lat, but it won't be great either.  I throw a wireless G signal 600 feet via directional antennae, dd-wrt, as said above. it adds a few ms to my ping avg, literally 3-4 ms.. that's a relatively short distance too, compared to yours.

so i wouldn't plan on gaming, but downloading/streaming/etc would work just fine.

it's all a matter of balancing power&heat =/= signal&noise ....


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## Mussels (Feb 25, 2010)

its not possible.

Remember, you need TWO way communication - high power transmitters and high sensitivity aerials to achieve long distance wifi.

Look at mobile phones - people freak out about cancer risks and such from the transmitters in them, and one side has maaaaassive transmitting power, while the other just has high sensitivity.


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## angelkiller (Feb 25, 2010)

Mussels said:


> its not possible.
> 
> Remember, you need TWO way communication - high power transmitters and high sensitivity aerials to achieve long distance wifi.
> 
> Look at mobile phones - people freak out about cancer risks and such from the transmitters in them, and one side has maaaaassive transmitting power, while the other just has high sensitivity.


But cell phones transmit data in two ways though. So whatever 'weak' transmitter they use is strong enough to cover those distances....??


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## TIGR (Feb 25, 2010)

I am confused on the question of whether or not high power is needed on both ends or just one one end. On the one hand, in the article I posted earlier, I gather that they are able to connect to access points ~8 miles away, and I would assume those access points are "regular" routers, not ones connected to super-antennae.

But here I am gathering that this is not possible, and a high-power transmitter is needed on both ends.

I'm sorry guys; I have a lot to learn on wireless networking.


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## Mussels (Feb 25, 2010)

angelkiller said:


> But cell phones transmit data in two ways though. So whatever 'weak' transmitter they use is strong enough to cover those distances....??



when you get poor coverage, its because you cant transmit back - not the other way around usually.


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## digibucc (Feb 25, 2010)

yeah they may be able to detect networks 8 miles away - but those networks can't sync/handshake.  as mussels said like a cell phone out of service - most of the time it is the phone that can't get a signal to the tower, not vice versa.


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## cdawall (Feb 25, 2010)

hows this for you

http://windsurf.mediaforte.com/wifi/wifi_antenna.html


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## AphexDreamer (Feb 25, 2010)

TIGR said:


> Did you ever notice or check what kind of latency the repeaters added to the signal? Just curious about that, and about whether they add significant noise to the signal.
> 
> And that brings up another thought to add to the [purely theoretical] discussion.
> 
> ...



I can't really remember. I had no complaints using it and it came up as 54mbps signal strength.


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## troyrae360 (Feb 25, 2010)

> They deemed it "reliable" since it their applications, ssh to each other's Linux laptop, VNC etc. were up and running uninterrupted for several hours while they waited for the judges to arrive.


 http://www.unwiredadventures.com/unwire/2005/12/defcon_wifi_sho.html


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## 95Viper (Feb 25, 2010)

TIGR said:


> I am confused on the question of whether or not high power is needed on both ends or just one one end. On the one hand, in the article I posted earlier, I gather that they are able to connect to access points ~8 miles away, and I would assume those access points are "regular" routers, not ones connected to super-antennae.
> 
> But here I am gathering that this is not possible, and a high-power transmitter is needed on both ends.
> 
> I'm sorry guys; I have a lot to learn on wireless networking.



Yes and No.  You do not need so called high power on each end.  As, Mussels said, about cell transmissions.  But, you will need more power than the normal router puts out and a boost to the input, because the input sensitivity on them are not made for reception of a signal that would be that weak at 2 to three miles.  At one mile you could probably pull it off with antenna tricks.  You need to get up to the 1 to 3 watt output range, which normal router can't do with the final output transistors they use. 

Build a bi-amp or buy one. Same with the antenna.
Links:
Good antenna is the original cantenna
http://www.notebookreview.com/default.asp?newsID=2859
http://www.google.com/products?q=Super+Cantenna+Wireless+Booster+Antenna&oe=utf-8&scoring=p
Bi-amps
http://radiolabs.com/images/products/wifi-amp-hook-up.gif
http://radiolabs.com/products/wireless/wifi-amplifier.php
http://www.rflinx.com/products/amplifiers/

Not the only amps and antennas, there are many different configurations, only limited to what you are willing to do to grab that signal.
Oh and, legality, it is still a gray area on an unsecured wireless network, as far as I know.  Just don't bust someone's secured stuff, now you are messing in a totally different arena.

But, IMO at 2 to 3 miles - Bi-Amp and good antenna.  If your input sensitivity can receive and use the the signal, then there is always a way to transmit to it. More Power...Scotty.


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## TIGR (Feb 25, 2010)

Big thanks to you 95viper, am looking over those links. Great stuff.

Thank you to digibucc too—so even though such a setup could detect those access points, it couldn't actually connect with them?

Naughty theoretical Johnny is actually just under two miles from the access point(s) in question. In theory. Sounds like that's significantly more feasible than transmitting 3+ miles. This would really help Johnny keep the constant Folding@home result-sending from bogging down his connection.


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## Zebeon (Feb 25, 2010)

Subscribed-

Hope to learn something...


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