flat assembler
Message board for the users of flat assembler.

Index > Heap > i want to build DIY wifi receiver that could receive signal

Goto page 1, 2  Next
Author
Thread Post new topic Reply to topic
sleepsleep



Joined: 05 Oct 2006
Posts: 8906
Location: ˛                             ⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣Posts: 334455
sleepsleep
hi,
i was assigned a task to build a DIY wifi receiver that could receive signal past 2 kilometers, is that possible..
it should be possible,,, right?

any guide or tips you guys wanna offer me??
Post 26 Mar 2010, 19:17
View user's profile Send private message Reply with quote
kohlrak



Joined: 21 Jul 2006
Posts: 1421
Location: Uncle Sam's Pad
kohlrak
Don't know much about DIY, but i know that with wireless things, an extra long antenna and more than usual power to it tends to fix distance problems. However, in most countries there're laws against that.
Post 26 Mar 2010, 22:45
View user's profile Send private message Visit poster's website AIM Address Yahoo Messenger MSN Messenger Reply with quote
farrier



Joined: 26 Aug 2004
Posts: 274
Location: North Central Mississippi
farrier
sleepsleep,

Search for "Cantenna". Also, you can use old satellite dish antennas for reflector/collectors. Empty Pringles cans are being recycled to do this everywhere!

hth,

farrier

_________________
Some Assembly Required
It's a good day to code!
U.S.Constitution; Bill of Rights; Amendment 1:
... the right of the people peaceably to assemble, ...
The code is dark, and full of errors!
Post 26 Mar 2010, 23:49
View user's profile Send private message Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
Are you talking about Wifi as in the Wifi standard used for Internet surfing at places like Starbucks? Or are you talking about wifi as in general radio transmission where protocols and frequencies and things are just whatever will make your system work?

Most countries will not allow such strong signals that travel 2km. Generally you are allowed up to 10mW and are restricted to within only certain frequency ranges. Usually you can get up to 100m range with a 10mW transmitter, perhaps more if you have a really clear path and a really good directional antennae.

If you want to support TCP traffic then the Wifi bands with a proper Wifi encoder chip would be the best solution. Cheap and easy. But if won't really be DIY, and it won't go 2km. Most manufacturer modules are pretty much already complete working systems with you just needing to add connection to a CPU and an antenna.

Are you just wanting low bandwidth RF, maybe for a SCADA system? At the power levels you are talking about you will need to get a license for the frequency you use.
Post 27 Mar 2010, 03:24
View user's profile Send private message Visit poster's website Reply with quote
nop



Joined: 01 Sep 2008
Posts: 165
Location: right here left there
nop
everybody is forgetting sleepsleeps task is to build the receiver not the transmitter
sleepsleep has no legal issues to consider he just needs to build a very sensitive receiver
is the transmitter using normal power levels sleepsleep Question
Post 27 Mar 2010, 05:28
View user's profile Send private message Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
nop wrote:
everybody is forgetting sleepsleeps task is to build the receiver not the transmitter
Well if that is the case then the answer is easy, it is not possible. No legal Wifi transmitter can be heard from 2km away. Unless perhaps you are building this in interstellar space and have a really-really-super-low-noise receiver amplifier circuit.
Post 27 Mar 2010, 05:35
View user's profile Send private message Visit poster's website Reply with quote
kohlrak



Joined: 21 Jul 2006
Posts: 1421
Location: Uncle Sam's Pad
kohlrak
Correct me if i'm wrong, but if this is for wifi, wouldn't stuff have to reach over 2km both ways? Unless this just takes random UDP packets and doesn't need to answer...
Post 27 Mar 2010, 06:17
View user's profile Send private message Visit poster's website AIM Address Yahoo Messenger MSN Messenger Reply with quote
MHajduk



Joined: 30 Mar 2006
Posts: 6034
Location: Poland
MHajduk
sleepsleep wrote:
hi,
i was assigned a task to build a DIY wifi receiver that could receive signal past 2 kilometers, is that possible..
it should be possible,,, right?

any guide or tips you guys wanna offer me??
sleepsleep if I'm not wrong you could use CB as a receiver/transmitter? It should be possible to communicate over distance of several dozen kilometers. Creation of the computer interface also shouldn't be too difficult. Moreover
Wikipedia wrote:
In many countries, CB does not require a license and, unlike amateur radio, it may be used for business as well as personal communications.
Post 27 Mar 2010, 11:41
View user's profile Send private message Visit poster's website Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
CB is not allowed for data transmissions, only for voice.
Post 27 Mar 2010, 12:07
View user's profile Send private message Visit poster's website Reply with quote
MHajduk



Joined: 30 Mar 2006
Posts: 6034
Location: Poland
MHajduk
revolution wrote:
CB is not allowed for data transmissions, only for voice.
Do you mean that it would be illegal to use this media for data transmission (because technical possibilities still exist)?
Post 27 Mar 2010, 12:21
View user's profile Send private message Visit poster's website Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
Yes, pretty much everywhere it is forbidden to use CB bands for anything other than live voice transmissions. Otherwise the bands would quickly be swamped by everyone wanting to use the free RF bands to transmit their data.

Remember it is a shared resource, so while you are using it, no one else can.
Post 27 Mar 2010, 12:27
View user's profile Send private message Visit poster's website Reply with quote
MHajduk



Joined: 30 Mar 2006
Posts: 6034
Location: Poland
MHajduk
revolution wrote:
Remember it is a shared resource, so while you are using it, no one else can.
Yes, I know. But I guess that sleepsleep meant the region with a low population density where doesn't exist any other media of communication? Then it wouldn't be such a big problem with shared resources...

OK, in this case he could use two radio stations to connect two computers in the isolated places. Maybe old military stuff would be good enough (I was thinking about such kind of solution a few years ago)?
Post 27 Mar 2010, 12:44
View user's profile Send private message Visit poster's website Reply with quote
Dex4u



Joined: 08 Feb 2005
Posts: 1601
Location: web
Dex4u
I think sleepsleep, means, he wants a good wifi aerial like a pringle tube.
http://www.oreillynet.com/cs/weblog/view/wlg/448
Post 27 Mar 2010, 20:37
View user's profile Send private message Reply with quote
sleepsleep



Joined: 05 Oct 2006
Posts: 8906
Location: ˛                             ⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣⁣Posts: 334455
sleepsleep
Quote:

Are you talking about Wifi as in the Wifi standard used for Internet surfing at places like Starbucks?

yeah, wifi standard as used in place like starbucks, mc donald, and kfc.

Quote:

everybody is forgetting sleepsleeps task is to build the receiver not the transmitter

hmm, i need both, it should be 2 way communicate.

maybe i need more time to review if i could complete the customer assignment or not..

but is that possible for standard wifi, the 802.11 a/b/g/n to travel over 2 km?? back and forward...??
Post 29 Mar 2010, 08:30
View user's profile Send private message Reply with quote
baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
sleepsleep,

Nothing is impossible, just highly improbable.

Key word is "signal-to-noise ratio". Directional aerial will pick up as much useful signal as noise from that direction. I do have QSL from EME to Australia, that's about 760'000 km distance. Wink
Post 29 Mar 2010, 09:10
View user's profile Send private message Reply with quote
YONG



Joined: 16 Mar 2005
Posts: 8000
Location: 22° 15' N | 114° 10' E
YONG
baldr wrote:
Nothing is impossible, just highly improbable.
Well, this task was proven to be impossible long long time ago. Wink
Post 29 Mar 2010, 09:36
View user's profile Send private message Visit poster's website Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
sleepsleep wrote:
but is that possible for standard wifi, the 802.11 a/b/g/n to travel over 2 km?? back and forward...??
No. You would have to go far outside the standards to do that.
Post 29 Mar 2010, 09:46
View user's profile Send private message Visit poster's website Reply with quote
edfed



Joined: 20 Feb 2006
Posts: 4238
Location: 2018
edfed
maybe a RF bridge based on FM or LW will help???

something like a CB communication, but with digital signals from an ethernet card... but a problem will be the speed... but the solution seems correct because it will be possible to communicate at very long distances.
Post 29 Mar 2010, 10:11
View user's profile Send private message Visit poster's website Reply with quote
baldr



Joined: 19 Mar 2008
Posts: 1651
baldr
YONG,

Trisection of an angle can be solved mechanically. While squaring the circle seems to be different (transcendental numbers and such), rational approach can give quite acceptable results (Bible mentions pi as being equal to 3 Wink).

__________
edfed,

802.11 has nothing to do with FM, it's microwave range.
Post 29 Mar 2010, 10:26
View user's profile Send private message Reply with quote
revolution
When all else fails, read the source


Joined: 24 Aug 2004
Posts: 17287
Location: In your JS exploiting you and your system
revolution
sleepsleep: Ask your local telecommunications company to lease you a digital line. Legal and easy.
Post 29 Mar 2010, 10:43
View user's profile Send private message Visit poster's website Reply with quote
Display posts from previous:
Post new topic Reply to topic

Jump to:  
Goto page 1, 2  Next

< Last Thread | Next Thread >
Forum Rules:
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum


Copyright © 1999-2020, Tomasz Grysztar. Also on YouTube, Twitter.

Website powered by rwasa.