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Best way to expand Internet by 300m — Parallax Forums

Best way to expand Internet by 300m

john_sjohn_s Posts: 369
edited 2010-11-19 07:12 in General Discussion
I have this "shack" that needs to be connected to Internet located 300m away from the Internet/WiFi networked office. I did some online search on the subject of repeaters / higher gain antennas / WiFi expanders and data over power lines. Now is the time to choose the optimal approach.

Is anybody using a set of such devices to recommend for the line of sight distance of 300m?

Comments

  • Coder96Coder96 Posts: 42
    edited 2010-11-18 00:36
    Whats the terrain like(Hill or flat)?

    Line of sight? Any buildings in the way? Any trees in the way? Property Lines?

    Biggest problem with RF. Organic material.

    Need a bit more information
  • localrogerlocalroger Posts: 3,452
    edited 2010-11-18 05:49
    If you have actual line of sight -- you can see one end of the link from the other with your eyes and visible light -- then ordinary wifi equipment, probably without even fancy antennas, will span this distance. If it's thickly forested or hilly you will either have to elevate your repeaters above the foliage and terrain or give up now and start running cable. (If 10 megabit bandwidth is good enough for you, you can save some money by running 10baseT over cat 3 aka ordinary phone wire instead of 100baseT over cat5, which is overkill for most internet access.)

    added thought -- if you have power run from the house to the shack, you might be able to use an ethernet-over-power link. I just installed a pair of these devices to link my lapidary saw controller to my home network, and they work surprisingly well. Distance might be an issue in your case though.
  • electrosyselectrosys Posts: 212
    edited 2010-11-18 07:36
    To expand my WiFi signal, I purchased a La Fonear+ router (with external antenna) and re-flash it with DD-WRT software, and now I'm using it as a WiFi repeater, my WiFi signal is now expanded about 300 meter or even more.
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2010-11-18 09:05
    Pringles cantenna:

    http://www.binarywolf.com/249/pringles_cantenna.htm

    -Phil
  • Beau SchwabeBeau Schwabe Posts: 6,568
    edited 2010-11-18 09:44
    There is something called "Free Space Optics (FSO) Laser Links" that can offer up to 2.5 Gbps and 4000 meters are possible. What I don't know is the price.

    Here is a website:
    http://www.airlinx.com/products.cfm/product/19-0-0.htm
  • Possum79Possum79 Posts: 30
    edited 2010-11-18 10:03
    I would really stay away from the power link options. We occasionally use them at where I work and they tend to be very glitchy. The ones we use say they can handle 85Mbps but after speed testing it slows down drastically from direct connection to a modem and the power link. I like the cantenna ideas, one thing you have to be concerned with if you think bigger is better when buying an antenna is if there is any local regulation as per the gain of the antenna. I would hard wire some cat 5e to 3 switches. max distance on that cable is 100 meters.
  • localrogerlocalroger Posts: 3,452
    edited 2010-11-18 10:10
    Possum, I'd agree that expecting true ethernet speed over a power link is probably unreasonable. I'm running a telnet session over it and it works fine, but I haven't tried watching video. My 3g and previous DSL internet connections top out at 1.5 mbit/sec anyway, so the advertised speed would be overkill.
  • john_sjohn_s Posts: 369
    edited 2010-11-18 12:23
    Beau Schwabe (Parallax) wrote: »
    There is something called "Free Space Optics (FSO) Laser Links" that can offer up to 2.5 Gbps and 4000 meters are possible. What I don't know is the price.

    Here is a website:
    http://www.airlinx.com/products.cfm/product/19-0-0.htm

    Thank's for the interesting link. Plenty of info on their wireless equipment. As far as the IR or laser link I'd rather say no, as for this particular app I prefer something w/o optics or extra wires, plain and simple wireless (say, available from a computer outlet :-)
  • john_sjohn_s Posts: 369
    edited 2010-11-18 12:27
    Coder96 wrote: »
    Whats the terrain like(Hill or flat)?

    Line of sight? Any buildings in the way? Any trees in the way? Property Lines?

    Biggest problem with RF. Organic material.

    Need a bit more information

    Flat terrain, no obstacles at all, Fresnel taken into account and no existent, no trees, foliage etc, (cannot say anything, about human ... er, organic contamination) - clearly seen Xmas lights from both locations :-)
  • john_sjohn_s Posts: 369
    edited 2010-11-18 12:32
    added thought -- if you have power run from the house to the shack, you might be able to use an ethernet-over-power link. I just installed a pair of these devices to link my lapidary saw controller to my home network, and they work surprisingly well. Distance might be an issue in your case though.

    It's rural Internet and a "shack" it was re-wired to accommodate usage of some industrial equipment (saw, drill, small generators, etc) . I expect trouble with Internet over power link due to this, plus possible trafo (or 2) on the way.
  • Dr_AculaDr_Acula Posts: 5,484
    edited 2010-11-18 16:00
    If you have decided wireless, then it probably comes down to choice of antenna. 10mw of RF is not much more than one xmas light so it is a tiny amount of power. The more you focus it, the further it will go.

    I've played around with video at 2.4Ghz and homemade antennas. Yagi and Quagi have quite amazing gain. More elements = more gain as the beam is focussed more. It comes down to the db gain number. Then there are the circularly polarised antennas.

    There is a freenet movement worldwide where people put their own repeaters on buildings and bounce signals around cities. I think they have got tens of kilometers. I've looked at some of their antenna designs as there are some quite intriguing ones, such as ones made of square metal downpipe with slots cut at specific points.

    I built my own yagis with about 20 elements, but these days you can buy similar ones for a very reasonable price http://www.dealextreme.com/details.dx/sku.33016

    16db may well be enough for 300m. If you want more gain, dish antennas can give gains of 24db http://www.citytechnology.com.au/microbeam/index.php?main_page=product_info&cPath=1_13&products_id=9

    This site describes 1 mile with 16db, though you might need to check the power they used http://www.w5vwp.com/hamradio/wireless.html

    One practical problem is you don't want long leads between the antenna and the router, but on the other hand, you get more range if the antenna is higher, so one might need to look at a waterproof box on a pole for the router/transmitter.
  • john_sjohn_s Posts: 369
    edited 2010-11-18 18:29
    So does it mean that without asking anybody (or violating any regulatory restrictions) by simply plugging any higher gain antennae I can expand the range of any wireless box (router, bridge, switch, etc) ?

    Also, any comments on wireless-bridge approach as in here?

    http://lairdtech.thomasnet.com/item/ice-provider-wisp-base-station-and-client-antennas/er-wisp-base-station-and-client-antennas-q-bridge-/wireless-bridge?

    btw. I visited your website and like the technical portion of what you did with Propeller a lot!
    (and I hope you're aware of how open your mailbox there's as well.. )
  • Dr_AculaDr_Acula Posts: 5,484
    edited 2010-11-18 19:49
    I gave up trying to keep my mailbox secret after it was released into the wild by, of all people, the Australian Government. Serves me right for sending in a public submission on an issue!

    Yes, I think what you need is a bridge. And from my understanding, most routers can be reconfigured as a bridge with some software changes, often via a 'web page' that the router generates.

    The antenna focusses the energy. A lightbulb in the open radiates all directions. Take all that energy and focus it in one direction, and it is like putting a torch reflector behind that lightbulb. So in most directions, using your directional antenna will actually decrease interference to your neighbours compared with an omni antenna. Since you are pointing it at your own shed, there should be no problems with interference.

    That wireless bridge looks pretty good. Check the price out and compare with building your own from individual bits. Looks like they have a bit more power on the RF side than the average router, but significantly less current consumption.
  • Possum79Possum79 Posts: 30
    edited 2010-11-18 22:05
    localroger wrote: »
    Possum, I'd agree that expecting true ethernet speed over a power link is probably unreasonable. I'm running a telnet session over it and it works fine, but I haven't tried watching video. My 3g and previous DSL internet connections top out at 1.5 mbit/sec anyway, so the advertised speed would be overkill.

    I was getting 18Mbps download right out of a docsis 2 modem. After connecting to the power link I was getting about 5Mbps download. Big difference. Although now I can get 105Mbps dl if I wanted to pay haha. I work for a local cable company right now and thats our highest speed available. Also the powerlinks can have problems if it's using a different electrical circuit like an additon to the house.

    I was looking at setting up a big WiFi before using a parabolic dish linked with some low loss cable going to my desktop card with external antenna. I purchased some 10DB gain omni direction antennas but never hooked them up. I didn't have the right connector as they have a reverse BNC on it and my Dlink card was SMA I believe, can't remember right now. My current router has built in antennas so no luck testing them out anytime soon.
  • tonyp12tonyp12 Posts: 1,951
    edited 2010-11-19 07:12
    You could try the antennas you already have with parabolic modification.
    http://www.freeantennas.com/projects/template2/index.html

    So you would need a router with external antennas,
    one that can be flashed with dd-wrt.

    http://www.youtube.com/watch?v=Ud-Hq3kgvk4

    In bridge-repater mode, only one ethernet jack works.
    And of cource the wifi signal behind the Sail is pretty weak.

    39.99 - 10% off coupon BTEZZZS27 - $20 rebate (Exp 11/23) = $15.99
    http://www.newegg.com/Product/Product.aspx?Item=N82E16833320023&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&AID=10440897&PID=1154737&SID=
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