Arduino Forum

Forum 2005-2010 (read only) => General => Bar Sport => Topic started by: kbelanger on Jan 17, 2011, 03:09 am

Title: 500-1000ft. range wireless communication
Post by: kbelanger on Jan 17, 2011, 03:09 am
What will be the best way to send data from an arduino to another arduino located between 500 and 1000 ft. away?

Thanks,

Keven
Title: Re: 500-1000ft. range wireless communication
Post by: jezuz on Jan 17, 2011, 03:41 am
Series 1 and Series 2.5 High Power Xbee's have a mile range, which would be good for you. They go for about $40 bucks a piece.
Title: Re: 500-1000ft. range wireless communication
Post by: retrolefty on Jan 17, 2011, 03:46 am
Range claims need to be taken with a gain of salt. Many such specs are based on best case line of sight with no interfering signals. Going through walls, thick vegetation, etc will shorten range. How much? I haven't a clue.

 But If I needed to span 500ft I would want something rated from say 2000ft on up, but that's me. I have past ham radio experience.  ;D

Lefty
Title: Re: 500-1000ft. range wireless communication
Post by: 48X24X48X on Jan 17, 2011, 05:26 am
The newer XBee ZB Pro is 3.2 km (~ 2 mile) for LOS. You would need to use higher gain antenna though. If your region allows the use of 900 MHz and 868 MHz band radios, go for that instead. :)
Title: Re: 500-1000ft. range wireless communication
Post by: AWOL on Jan 17, 2011, 06:49 pm
'Best' is a pretty meaningless term.
Best in terms of what?
Speed of transmission?
Security/reliability?
Cost?
Battery life?

I'd probably recommend cellular, but a simple laser bounced off low cloud could be the right answer.
Title: Re: 500-1000ft. range wireless communication
Post by: retrolefty on Jan 17, 2011, 07:06 pm
Quote
but a simple laser bounced off low cloud could be the right answer.


Cool, you got a sketch for that? How do keep from pissing off random pilots and having them report one to the FAA (or whatever your plane police are called in U.K.) ?  ;D

Lefty
Title: Re: 500-1000ft. range wireless communication
Post by: AWOL on Jan 17, 2011, 07:43 pm
Well, obviusly, the OP is in Canada, and therefore:
1)Is in the middle of nowhere
2)why would pilots be flying below lo cloud
3)obviously, the in built clear sky detector would automatically inhibit the laser when necessary. But then, again, it is Canada, so that seems unlikely.

;D
Title: Re: 500-1000ft. range wireless communication
Post by: retrolefty on Jan 17, 2011, 07:47 pm
Canada, of course. Can't he just interface with two tin cans attached to long string?

Lefty
Title: Re: 500-1000ft. range wireless communication
Post by: kbelanger on Jan 17, 2011, 08:10 pm
Yes in Canada, particularly from the north of Québec (http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=Taschereau,+Quebec,+Canada&sll=55.825973,-74.970703&sspn=29.363022,79.013672&ie=UTF8&hq=&hnear=Taschereau,+Abitibi-Ouest+Regional+County+Municipality,+Quebec,+Canada&ll=48.662907,-78.68125&spn=0.015533,0.038581&z=15&iwloc=A)

In an agricultural area, I'm the owner of an IT company and a family farm where we raise porks and beefs among others. I want to monitor some data in our farm (temperature and humidity of certain location, water pressure/level. Also want to be able to close water valve, schedule lightning, etc.. We already have some camera for gestation and birth monitoring.

I also plan to automate some task in our green house and garden.

All those data/control should be accessible via a computer in the house.

We already have a wi-fi (mikrotik) link beetween house and farm for camera and voip phone, internet/Lan connection but I'm looking for other technology to transmit data from green house and garden.

There is no vegetation in the path.

Plane a running straight over my house, also a lot of small plane are visible at low altitude ;)

48X24X48X: Which kind of 900 MHz and 868 Mhz radio are you talking about?

I think that you have all needed details ;)
Title: Re: 500-1000ft. range wireless communication
Post by: cowjam on Jan 17, 2011, 08:12 pm
Quote
Going through walls, thick vegetation, etc will shorten range.


Having messed around with directional wifi I can tell you that walls are a bastard.  
Title: Re: 500-1000ft. range wireless communication
Post by: RanTalbott on Jan 17, 2011, 09:24 pm
What volume of data are you sending?  An Xbee may not have the bandwidth you need:  they max out at 115K, even under ideal circumstances.

Only slightly more expensive would be to set up a couple routers, reflashed with dd-wrt, with Yagi antennas to maximize range and avoid interference.  That would give you an Ethernet link for cameras and such, plus (if you pick the right router) a TTL serial port to interface to an Arduino.

For a really solid, professional 900MHz link (though also limited to 115K), check out the MaxStream radios from Digi.  I know people who've done 10-mile-plus links with them under near-ideal conditions (central node on a mountain top, in the desert).
Title: Re: 500-1000ft. range wireless communication
Post by: cowjam on Jan 18, 2011, 07:20 pm
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Only slightly more expensive would be to set up a couple routers, reflashed with dd-wrt, with Yagi antennas to maximize range and avoid interference.

Isn't the frequency wifi uses not particularly good for distance?
Title: Re: 500-1000ft. range wireless communication
Post by: RanTalbott on Jan 18, 2011, 08:21 pm
Quote
Isn't the frequency wifi uses not particularly good for distance?

Yes, and part of the reason it was chosen is that it enables relatively-close networks to operate without "jamming" each other.

But 1000 feet isn't a huge distance.  By using highly-directional antennas, like a Yagi,  you can "focus" the transmitted energy so much more of it lands on the intended target,  instead of scattering in all directions.  That means a link that would work poorly,  or not at all,  with omni-directional antennas can be rock-solid.   Plus, out in the country there are very few competing WiFi nets,  so the signal-to-noise ratio also goes up,  and the odds that you'll accidentally mess up a neighbor's network go way down.

This wouldn't necessarily work well in the cities or suburbs, but is probably fine for Keven.
Title: Re: 500-1000ft. range wireless communication
Post by: cowjam on Jan 18, 2011, 08:30 pm
Quote
This wouldn't necessarily work well in the cities or suburbs, but is probably fine for Keven.


I hadn't spotted his second post.

He's already got his remote location networked, he'd be better picking up a couple of ethernet shields.
Title: Re: 500-1000ft. range wireless communication
Post by: retrolefty on Jan 18, 2011, 10:11 pm
And an improved/better/higher antenna is the one single device that can improve both transmitter range and receiver sensitivity for the same dollar investment.

Lefty
Title: Re: 500-1000ft. range wireless communication
Post by: Jeckson on Jan 19, 2011, 07:06 am
When used wifi..the gain antenna is the problem.
used arduino with ethernet shield or wifi shield should OK.

J
Title: Re: 500-1000ft. range wireless communication
Post by: 48X24X48X on Jan 20, 2011, 05:26 pm
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Which kind of 900 MHz and 868 Mhz radio are you talking about?
I'm referring to the ones from Digi, the XBee-Pro for 868 MHz version and XBee-Pro XSC for 900 MHz. For LOS, the 868 can reach 40 km with adequate antenna gain. Sparkfun carries them.