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Wireless Networking Hardware

Wi-Fi World Record 235

supersam writes "Interline Wireless Technology, a Polish company has reportedly set a world record in stretching the range of a Wi-Fi network for an amazing 110 Kms at 2.4 GHz. They achieved this using an antenna developed by them and an INTEL Pro/Wireless 2011 Access Point."
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Wi-Fi World Record

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  • by Cyno01 ( 573917 ) <> on Tuesday September 23, 2003 @08:55AM (#7032932) Homepage
    Unfortunately the neighbors decided to microwave a burrito and their throughput went all to hell.
  • Polish (Score:5, Funny)

    by Crash42 ( 116408 ) on Tuesday September 23, 2003 @08:56AM (#7032936)
    Well, my polish is not that good (except my RPN/RPL) so i'll take your word for it....
  • by heir2chaos ( 656103 ) on Tuesday September 23, 2003 @08:56AM (#7032937)
    How many pollocks did it take to acheive this?
    • In this case, five :)

      # Piotr Kroplewski - owner of INTERLINE, who supplied the antennae
      # Wieslaw Karpowicz - production manager
      # Maciej Kaminski - director of technology dept.
      # Krzysztof Mularczyk - wireless networks expert
      # Krzysztof Juszczyszyn - tech dept.
  • by thoolie ( 442789 ) on Tuesday September 23, 2003 @08:56AM (#7032941)
    "stretching the range of a Wi-Fi network for an amazing 110 Kms "

    Man, I never thought they would be able to strech the thing 110 Kilometer seconds!

  • 110 Km? (Score:2, Funny)

    by JRHelgeson ( 576325 )
    WOW! 110 Kilometers! What is that, like 500 feet?
  • Err... it is a cheat (Score:5, Interesting)

    by arivanov ( 12034 ) on Tuesday September 23, 2003 @08:56AM (#7032945) Homepage
    Err... My polish is crap, but unless I am mistaken they seem to have used a 500mW aplifier and a 27dbM antenna to boot.

    What's next? Sticking it in the middle of Aresibo and claiming half a light year range?

    • by Zocalo ( 252965 ) on Tuesday September 23, 2003 @09:15AM (#7033070) Homepage
      What's next? Sticking it in the middle of Aresibo and claiming half a light year range?

      Pshaw! Who needs Arecibo? *My* crappy off-the-shelf 802.11b card can get *infinite* range un-aided! True, picking the signal out from the noise at more than 50ft is proving problematic at present, but once I've ironed out that minor problem I'm well on my way to PROFIT!!!

      Or was I the only person paying attention in physics when it was explained how *any* electromagnetic transmission has infinite range, since decaying amplitude in accordance with the inverse square rule never reaches zero? Assuming a perfect vacuum, naturally.

    • from memory, there's a legal maximum to what you're allowed to broadcast wifi with without a licence. it'll be less than half a watt as well...
      • This would not be legal in the US based just on the antenna which is 27dBi, the max gain you can have with a 100mW card is 24dBi. In addition they used a 500mW linear amplifier which makes the output power many times more than the FCC allowed limit and probably creates all sorts of nasty noise on adjacent frequencies.
        • by div_2n ( 525075 ) on Tuesday September 23, 2003 @10:45AM (#7033901)
          Actually you can't use a 24db antenna with a 100mw card. The maximum EIRP allowed under the FCC for point to point is 8 watts (39db) and 4 watts for point to multipoint. If you use 100mw (20db) input into a 24db gain antenna, your total EIRP will be 44db or 25 watts. Not legal at all. Also not healthy to stand in front of the antenna for more than a few minutes.
          • Sorry man. This is redundant, but I still can't get over how dumb the FCC comment was.

            Even if you DO go over that FCC limit...whos checking? Do you think the FCC is going to wander by my house, directly in line of sight of my dish and measure me?

            It is directional...they can't monitor it from their spaceship parked over washington.

        • You can run 1 watt into a 6dbi antenna. For point to point you need to reduce your transmitter power 1db for every 3db increase in antenna gain. This means the max antenna gain for 500mw would be 15dbi. Add 9db to the gain to get 24bdi and you need to drop power another 3db or 250mw. 100mw would be legal at 27dbi but not 500mw. Since you need to increase total gain 6dbi every time your double your distance this would make this shot easy with 27dbi antennas and 500mw amps. I have heard of 20 mile links using
  • Hrmm (Score:5, Funny)

    by acehole ( 174372 ) on Tuesday September 23, 2003 @08:57AM (#7032946) Homepage
    I guess using two pringles cans instead of two really did the trick.

  • by Anonymous Coward on Tuesday September 23, 2003 @08:57AM (#7032954)
    110kms??? What's that in freight trains?

    or how many of the sears tower layed on it's side?

    • Sears tower = 442m
      Boxcar = 43 feet avg (
      Avg freight train length=45 cars
      Avg lenght in feet = 1935 feet

      google tells me theres
      • DAMMIT!

        apparently pressing ctrl-enter submits ... same as how I submit tickets .. stupid habits die hard.

        lets continue that.

        Sears tower = 442m
        so we have 248.8688 sears towers

        Boxcar = 43 feet avg (source [])
        Avg freight train length=45 cars (some other site that won't load but is cached)
        Avg lenght in feet = 1935 feet

        google tells me theres 0.3048 metres in a foot [] so we have the avg freight train being 589.788m long.

        That means we have 186.5077 freight trains (not counting engines) end to end
        • When comparing football fields, it's imortant to compare apples to apples. The length of the Canadian football field is 110 yards (which, although close, is not 100m). The endzones on a Canadian football field are 20 yards deep (each). An American football field is 100 yards in length. The endzones are each 10 yards deep.

          Despite the erroneous quote you found that compared the length of one field to another, the relative lengths of the fields are either 110 yds vs. 100 yds (Canadian vs. American using j
  • Huzaa! (Score:2, Funny)

    by rf600r ( 236081 )
    Maybe there's hope for me getting a signal down the hall?

    • I wonder if this could be useful for, say, Armadillo Aerospace. I think that they're using 802.11b at the minimum bandwidth with a 1 watt transmitter for their remote control on flights. Perhaps something like this could increase reliability.
  • by 192939495969798999 ( 58312 ) <info AT devinmoore DOT com> on Tuesday September 23, 2003 @08:58AM (#7032957) Homepage Journal
    or 66 miles for the math impaired (sigh). Still, that's rad! You could access that across the English channel!
    • by zerocool^ ( 112121 ) on Tuesday September 23, 2003 @09:11AM (#7033047) Homepage Journal
      I don't know about across the english channel. At some point, you pass the horizon, where you can't go any further due to the curvature of the earth. I was pretty sure that level was around ... either 50 or 100 miles, I don't remember. Can you see France from Kent?

      • Can you see France from Kent?

        You can, though it is easier to see Kent from france, as the white cliffs of dover stand out quite well.

        BTW, it is about 20 miles, (across the straights of dover) and there are tall cliffs on both sides, which improves sight lines

      • I don't know about Kent, but on a clear day you can see the rocks of Dover just fine from Cap Griz Nez.
      • by akadruid ( 606405 ) * <slashdot@thedrui ... minus physicist> on Tuesday September 23, 2003 @10:30AM (#7033736) Homepage
        I don't know about across the english channel
        Damn straight you don't!
        Distance will not be a problem - at only 21 miles (34 km) across at the narrowest point, weather permitting, you can clearly see 'Le Francais' from the White Cliffs of Dover.
        you can't go any further due to the curvature of the earth
        WTF? Surely you can't see any further! Actually you're miles out here too.
        The distance (in km) of the horizon on earth, on a plain, is approximately s(13h) where h is the height (in metres) of the eyes multiplied by the 13, and s is the square root symbol slashcode can't cope with.
        Were you to mount an antenna on the beach, you would find that the horizan at around 5km away would be a big problem.
        Stick it up on said White Cliffs of Dover, at 250m above sea level, and you will have no problems with line of sight.
        The only barrier to this idea is the regulations governing the area.
        Sources: Channel [], Cliffs [], Horizan []
        • heh, thanks for setting me straight. That's really interesting, to think that you could have wireless across the channel, although, with the exception of the ocean, I guess it's not too much different than sending a signal from france to spain.
          • As with everywhere else, the technology is no the limiting factor here, but the regulations. It would not be possible under current UK law to mount the transmitter this side of the Channel. I'm not sure about France - you may have more luck there. I the South-East of England, you cannot receieve on of our terrestial channels due to French interferance in that area. Not that anyone watches Channel 5 anywhere else anywy.
      • At some point, you pass the horizon, where you can't go any further due to the curvature of the earth

        The earth is flat [], sinner.

      • The distance to the horizon can be calculated using the formula:

        D = 1.17 * sqrt(h)

        where "D" is the Distance to the horizon (in nautical miles); and
        "h" is the height of the observer (or antenna) in feet.

        To find the distance you can communicate over the earth using line-of-sight communications (like 2.4 GHz is), you need to do the DTH (Distance to Horizon) calculations for each antenna, and then add them together. This gives you the total distance.

        To get the required 110 km, you would need two antennas

    • by Rosco P. Coltrane ( 209368 ) on Tuesday September 23, 2003 @09:25AM (#7033125)
      You could access that across the English channel!

      Yes, and just imagine the improvement when they finally dig the 802.11b tunnel!
  • (error 1337 destination page /.ed) Is increasing the range of current wireless networking equipment really what is needed. I know i personally am turned off from wireless not because of the lack of range, but the lack of speed. There is certainly some cool factor being able to get that masssive a distance, but I dont see this as making wireless more desirable to anyone.
    • 802.11g claims 54Mbps - how much faster do you need? hell, 11b is 11Mbps. that's still faster than most people's internet access.

      the speed is where it needs to be (for now). i am very interested in getting a signal that doesn't crap out when i go to the other side of the house.

      anyone got a link for a comparison of AP brands vs. range? comments on the linksys signal booster?

      • 802.11g claims 54Mbps

        "802.11g is still a 54Mbit/sec standard," Bell told MacCentral. "802.11b is 11Mbit/sec, but your actual throughput is somewhere between 4 and 5-1/2Mbit/sec. The number that's quoted is the data rate that's used between the radios (raw data rate, which includes the protocols etc.)"

        Although internal tests have shown slightly higher data rates, the actual data rate for 802.11g will be approximately 20Mbit/sec, which is 4 to 5 times higher than 802.11b. Bell said the data rate has alway

      • Not only do they not typically reach more than half those speeds in actual throughput, but 802.11g reverts all of its users to 11b speeds in the presence of any 11b client and that is a shared bandwidth. I live in condominiums and my 11b gets so much interference that my connection is lost from 10 feet away about once every 3 minutes (multiple stations and client cards, same problem, so not a hardware issue). And since the bandwidth is shared, there really is no possibility of creating home multimedia net

      • by _avs_007 ( 459738 ) on Tuesday September 23, 2003 @01:29PM (#7035266)
        I work with a lot of wireless APs and client cards in our lab.

        If you are talking about G type stuff, stay away from Linksys, they have the crappiest range. When I used it in my house, I would get 68db with an Intel 802.11b AP, but the Linksys G router/AP yielded 77db, and that was only going through 2 walls.

        I replaced it with a Netgear WGR614, which uses the Intersil Prism GT chipset (as does the D-Link we tested), and got much better range. Similar to straight B. ~68 or 69 db in my master bedroom.

        In our office environment, the Linsys G would drop signal after walking past the conference rooms. The Netgear G allowed us to almost walk around the entire floor. I connected a signal booster, and found it to be next to worthless, as it did not improve range. If it did, only by 5 ft or so. It still dropped signal as I walked past the conference rooms.

        The measured actual throughput was 4.5mb/s with straight 802.11b, and 21mb/s with the Netgear G.

        Quite suprisingly, I had the best results with the Netgear WAB102 Dualband A/B, which is the only A/B AP that uses Atheros second generation A. Tom's Hardware had a write-up on this. Atheros had a whitepaper. I bought 3 of these, and verified the claims.

        With a Linksys A+G card, (which uses Atheros 5001X+, as does Netgear WAG511), I got slightly weaker signal strength in my master bedroom 70db), but throughput killed both B and G. I was measuring 24mb/sec throughput in non-turbo mode, and 45mb/sec in turbo mode. In the office, I was able to sustain 7-11mb/sec at the opposite end of the building. The Netgear G was only able to sustain 1-2mb/s. Inside the conf rooms, Linksys G had no signal, Netgear G sustained 7mb/sec, Netgear A in turbo mode sustained 24mb/sec.

        In the office, the range of this second generation A actually exceeded that of B, which is something Atheros pointed out in their whitepaper. They said while true A can't go through walls as well as B, the 1st generation A was not performing up to its capabilities. Kind of like how Shannon's law states what is the maximum amount of data that can be carried across wireless, but current technology does not even begin to approach this limit.

        I've tested various client cards from Orinoco, to Cisco Aeronet, Prism 2 and Prism 3 cards, and various Atheros based cards. I that the AP affected range more often than the client cards. Though I have found that anything based on the Atmel chipset to be crap. The USB 802.11 card from Linksys (V2.6) uses this chipset. Unfortunately, the Netgear WAB102, uses Atmel for its B, so its B is crap as well. I just use the A portion of it anyways. But the new Netgear triband router, I beleive uses Atheros for all three bands, it just costs an arm and a leg.

        The Linksys Triband AP, only uses Atheros for the A, it uses Broadcom for B and G, so its G sucks just like the Linksys B/G stuff.

        Somewhere I also read that Linksys will not support any turbo modes in their AP/Routers. (though their A+G client card still supports turbo). Both Atheros and Intersil have planned turbo features. Atheros already had 108mb/s A support in turbo, allowing 45mb/sec throughput by using multiple channels. They already have support for hardware compression, so are promissing a future firmware update that will flip this on, that will allow a turbo mode to sustain 90mb/sec throughput. Its called SuperA. They just released SuperG, which uses multiple B/G channels and compression, to allow 108mb/sec, and I think 45-60mb/sec throughput.

        Intersil's turbo technology is called Nitro. Similar (but incompatible) with Atheros's technology.
  • by tbase ( 666607 ) on Tuesday September 23, 2003 @09:04AM (#7033006)
    Hey - that antenna they're using looks a lot like the one from this story []. Of course, he only claims a LOS range of 10 Miles.
  • by ausoleil ( 322752 ) on Tuesday September 23, 2003 @09:04AM (#7033013) Homepage
    I for one find it ironic that someone can detect and possibly decode my WiFi signal from roughly 70 miles (per the new world WiFi record) but I can't get a useable signal on my laptop three rooms away from the WAP.

  • by JRHelgeson ( 576325 ) on Tuesday September 23, 2003 @09:04AM (#7033014) Homepage Journal
    We /. the site, and it's not even in english. Who's going to RTFA when it's in polish?

    Anyone got a Polish->English translator?

    I checked Google, Babblefish & with no luck.

    • see "Some details" further down.
      I didn't translate, but I summarized the most important bits.

      Here's the equipment they used (which I didn't include in my other post):

      # Antennae - Interline PARABOLIC maxi, 27 dBi
      # Access Points - INTEL Pro/Wireless 2011 Access Point, made by SYBMOL
      # Cables and connectors - BELDEN H-1000, H-155, RG-316, VITELEC connectors
      # Wireless cards - Lucent ORiNOCO PC Card Silver/chipset Agere, ZCom XI-300/chipset Intersil
      # Amplifier - 2.4 GHz, 500 mW
  • I wonder how many pringles cans that took.
  • by miodekk ( 680870 ) on Tuesday September 23, 2003 @09:07AM (#7033032)
    The folks used devices that are freely available on the market (WiFi or WLAN PCMCIA cards, amplifier, antennas, etc), chosen locations within the range of about 66 miles (110 km) with visibility (to achieve this you must see the other point).
    So this is a relatively cheap method to get Internet access in distant locations, specifically in mountains, where it is difficult to get a wire.


  • Some details... (Score:5, Informative)

    by Sherloqq ( 577391 ) on Tuesday September 23, 2003 @09:07AM (#7033034)
    The article claims the experiment used off-the-shelf, commercially available, unmodified components (1.1m / 3.5ft parabolic antenna and a 500mW amplifier). Experiment was conducted in a mountainous region in southwestern Poland.

    So this isn't all that bad... considering the average laptop wireless card puts out, what, 20mW? 50mW? using a 500mW amp to achieve a much greater distance is pretty sweet. By comparison, the article quotes a Swedish experiment which used stratospheric baloons and a 6W amp, but they don't mention the distance achieved.

    Mind you, rules about how much power certain appliances / transmitters can put out with or without a permit vary across the globe, and I'm not sure whether 500mW is legal for private unlicensed use in Poland or not. But if it is, more power to them.

    Now, where can I get mine?? :)
    • Re:Some details... (Score:5, Informative)

      by Sherloqq ( 577391 ) on Tuesday September 23, 2003 @09:19AM (#7033090)
      Few more notes...

      Initially they didn't use an amp, and were getting 20% thruput, which allowed for a 1Mbps link to be established. That link kept going down every few seconds, tho, so they put in the amp. This boosted their RSS readings from 8 to 28, which meant 80% thruput. Having reached that, they tried to ftp a file and although they don't say how big it was, it was copied over at 40kBps, or around 0.5Mbps.

      I don't know about you, but seeing ping replies in the single digits and low teens while ~70miles away makes my spine tingle.
      • Sorry, your notation confused me. The file transferred at 40KiB/s. That's 0.5Mbps or about half-T1. I get it :)
      • I don't know about you, but seeing ping replies in the single digits and low teens while ~70miles away makes my spine tingle.

        Uh, that tingling is the 500mw microwave signal cooking your spine.
    • Typical cards have a max transmit power of 50mW and the good ones (like Cisco's) have a max of 100mW. I'm not sure if Poland's entry into the EU means that they fall under ETSI regulations, but if it does this most certainly was NOT legal as the ETSI standard limits transmit on cards to 50mW and point to point links are even more limited to than the US (which is 24dBi gain on a 100mW card).
  • by wherley ( 42799 ) * on Tuesday September 23, 2003 @09:08AM (#7033037)
    Here []
    is the story from July of an outfit getting 310km using WiFi from ground to a balloon. This was done by Alvarion and the Swedish Space Corporation and acknowledged by Guinness (as in world records not as in beer).
    • The weather balloon reached a maximum height of 29.7 km and drifted steadily. It finally touched down east of Sodankyla in the northern part of Finland, having travelled approximately 315 Km.

      On the balloon, the BreezeNET DS.11 unit was connected to a high-power amplifier with 6 watts power output, a camera and a server.

      Impressive though the achievement is, it has no bearing on how WiFi networks are allowed to work on Planet Earth. Down here, you're restricted to much lower power outputs and much smaller a
    • acknowledged by Guinness (as in world records not as in beer).

      The are actually the same company. (seriously)

  • by Rosco P. Coltrane ( 209368 ) on Tuesday September 23, 2003 @09:14AM (#7033067)
    Good thing they did that in Poland. If they had tried this in the US, they'd have been sued by DirecTV for hacking a satellite TV system and the RIAA for trying to set up a P2P link. Of course, none of this would matter since they'd all be in a 3x2 federal pen cell awaiting for months to be charged with setting up a data link that could be used for terrorism ...
    • by waspleg ( 316038 )
      you don't need tobe charged with anything to be detained indefinitely for being a terrorist

      you just have to be suspected... better not try adding wifi to your donkey

    • since they'd all be in a 3x2 federal pen cell

      Now, now. You know you're not supposed to make a reference on Slashdot to the Federal corrections system without calling it "Federal pound-me-in-the-ass prison".

  • by josecanuc ( 91 ) * on Tuesday September 23, 2003 @09:15AM (#7033068) Homepage Journal

    105 km is a good ways off. But Amateur Radio operators have been getting better than this with their voice transmissions (and possibly digital) on frequencies from 50 MHz to 10 GHz at the 2003 September VHF QSO Party.

    See some of their setups at [].

    Our university station was making contacts on frequencies greater than 2.4 GHz for distances longer than 200 miles. Contrary to common sense, Line-of-Sight is not necessarily required to get microwave transmissions to work over long distances. But they're very weak ;-)

  • by AmigaAvenger ( 210519 ) on Tuesday September 23, 2003 @09:16AM (#7033077) Journal
    The article already is almost dead... Can't check how they did it, BUT... the biggest problem isn't signal power, that part is easy with even a minimal amp and decent parabolic grid antenna. The tough part is the curvature of the earth. Beyond 10 miles or so, you have to get your antennas substantially off the ground, otherwise the amps and high gain antennas make absolutely no difference...
    • According to the page, one of the antenas was on the roof of 10-storey building in Wroc?aw
      (city is located in between 100 and 148 meters above sea level), and (as I believe - it's /.'ed now) the Sniezka mountain (which is 1602 meters above the sea level). Thus the antenas were substantially off the ground...
    • you have to get your antennas substantially off the ground ... which is what they did. One of the antennas was on top of a 10-story apartment building, the other was on the side of a mountain, 1400 meters above sea level (which is around 4800ft) with hardly anything in between (see map []).
    • The tough part is the curvature of the earth.

      Silly! That's why the expirement was done in Poland! The Earth is still flat out there!

    • Well, it's not 'that' bad.

      At 66 miles, a 60% Fresnel zone would be around 195'.
      At 66 miles, the curvature of the earth would be about 160'.

      Combined, for a 60% fresnel, you're looking at antenna heights (center of radiated power) at about 160 + 195 = 365 feet.

      However, if the angle at which the 10 story building was 'looking' high enough up to the mountain top, they could have made it, but at 66 miles, I doubt it. There was no doubt some measure of reflection/refraction of the signal by terrestrial objects
  • 3603 miles, between me in Paris and my friend Bob in New-York:

    My_laptop <-> my_AP <-> The_innurnet <-> Bob's_AP <-> Bob's_laptop
  • It will only mean that last mile solutions will become more plausible for those who don't live within a couple miles of their CO. This is a Good Thing, as having Dial-Up and Satellite as your only options is pretty unbearable.

  • by puzzled ( 12525 ) on Tuesday September 23, 2003 @10:28AM (#7033707) Journal

    I did a 21.7 mile shot using Cisco Aironet BR342, Andrew 19dB solid dishes, and YDI []
    500 mw amps.

    I'm a bit embarrased to admit using a wireless LAN product for backhaul work, but some morons [] overtightened
    the patch cable on an Andrew P2F 5.2-5.8 GHz 2' dish hooked to a WiLan AWE-120 5.8 GHz radio and put their link out
    of service.

    Despite extensive tweaking the link never managed more than analog modem speeds. It helped in recomissioning the UNI band stuff, but was otherwise
    useless for hauling traffic.

    802.11[bag] is NOT an access product. Take a look at Alvarion's [] Breeze Access II, or better yet just wait for an
    802.16 product meant to do access work.

    802.11[bag] is NOT a mobile access product. That market belongs to licensed band products with ISDN like performance offered by cellular companies.
    Anecdotal evidence of mobile access to one police department in a town of 12,000 does not equal proof of concept for operation in urban areas; its plain
    dumb luck coupled with no competing ISM band ISP(yet).

    802.11[bag] is NOT a backhaul product. Backhaul radios are made by WiLan, Redline, Aperto, Proxim, and others. The minimum cost is $2,500 an end just for
    the radio, most of them are in the UNI band, the full duplex products are generally split band 5.2/5.7 GHz, and they provide typically eight to ten
    mbits for entry level products, unlike 802.11b which NEVER, EVER gets 11 mbits in long shots, with 1 or 2 mbits being the typical rate.

    802.11[bag] SHOULD NOT BE DEPLOYED BY MONKEYS. Are you a MoNkEy? If you haven't read Matthew S. Gast's 802.11 book published by OReilly and you
    don't fully grok the implications of the shared MAC layer, you are just throwing nuts and filth from the treetops into the already busy ISM band.

    Slashdot's coverage of other topics is relatively even. The coverage of radio is focused on 802.11[bag] and this is quite laughable most of the time
    to those of us who have actually owned and operated a wireless ISP. Personally I think the editors ought to be giving us a whole lot more information
    on ICOM's D-STAR [], a 23cm (1.2 GHz) amateur band voice/data system.

  • Translation (Score:3, Informative)

    by Anonymous Coward on Tuesday September 23, 2003 @11:23AM (#7034257)
    Below is my rough, quick and dirty translation of the article. You will have to mach the text to the pictures yourselves. AND it's Polish, not polish. For the difference of meaning see your favourite dictionary.


    Wi-Fi - World Record - 110 km @ 2.4 GHz

    Two-way DSSS communication in 2.4 GHz band at a distance of 110 km

    INTERLINE company, leading Polish microwave antenna producer, set itself a goal to check possibility of establishing a wireless link in 2.4 GHz band with sequential spectrum spread DSSS (802.11 b standard) at a range currently being only a subject theoretical dispute. The aim of the enterprise was a practical assessment of possibilities and study of phenomenas concerning such a link.

    It should be stressed that the link built is typical ground link and that diversivies it from the one built at the end of 2002 by Swedish company Alvarion and Swedish Space Corporation, which used a stratospheric baloon.

    What is equally important, all elements used in the INTERLINE experiment are off-the-shelf, unmodified equipment available comercially (1.1 meter parabolic antenna and a 500 mW amplifier). Swedish experimentators used 2.4 m parabolic antenna and a 6000 mW amplifier.

    Two localisations were chosen for the link: Wrocaw (a city) and a Hala pod Sniezka (Sniezka is a highiest mountain of Karkonosze), S-W from Jelenia Gora. The distance is around 110 km.

    In the experiment actively participated:
    Piotr Kroplewski - owner of the INTERLINE
    Wiesaw Karpowicz - Manufacturing Manager
    Maciej Kaminski - Technical Division Manager
    Krzysztof Mularczyk - Wireless Network Specialist
    Krzysztof Juszczyszyn - Manufacturing Technologist

    One of a key stages of the experiment was a choice of localisations for stations which were to create a point-to-point link. First of them is a 11 stage house on a one of Wroclaw's districts.
    Second one, key to the experiment, is a glade by the summit of nieka, nerby Dom lski shelter (1400 meters above sea level)

    For the experiment following equipment was chosen:
    Antenas: PARABOLIC maxi, 27 dBi - product of INTERLINE
    Access points: INTEL Pro/wireless 2011 Access Point - made by SYMBOL
    Cables and connectors: cables BELDEN H-1000, H-155, RG-316, connectors VITELEC
    Wireless cards - Lucent ORiNOCO PC Card Silver/chipset Agere, ZCom XI-300/chipset Intersil
    aMPLIFIER - 2.4 GHz, 500 mW

    Of course there were also 2 laptops. Additionally we had: UPS, a set of tools, spare cables, connectors and a gas solder (just in case).

    End-point Wroclaw
    As the date of the experiment was set a time between 12th and 14th of September 2003.

    First stage was mounting and directing an antena in Wroclaw to point towards nieka mountain. Due to good visibility in Wroclaw in the day of installation (2003.09.12), this mountain, which is 1602 meters above sea level, was clearly ivsible. During the directioning vertical angle was important, due to the fact, that the other end of the link was 1400 meters above sea level.

    Installation components
    1. Access Point
    INTEL Pro/Wireless 2011 Access Point + Amplifier 2.4GHz/500 mW
    (here you can read yourself)

    2 Antena cable
    Belden H-1000
    Length: 5 meters
    plugs: type N

    3 Connector
    Length 30 cm (0.3 m)
    plugs: type N and RP-BNC

    4 ANTENA
    type: directional parabolic antena
    gain: 27 dBi
    radiation angle: 4degrees/6degrees

    Installation - Karkonosze mountains, Kopa-nieka
    On 14th September 2003 all the equipment has been transported with OPEL Frontiera (we had obtained permission of the Karkonosze National Park authorities) to the meadow near the nieka's summit.

    On the installation place weather was as usually in the mountains. Almost all the time the place was covered by clouds. Only from time to time for a dozen seconds wind split the clouds and we were offered splendid views of surrounding mou
  • During the directioning vertical angle was important, due to the fact, that the other end of the link was 1400 meters above sea level.

    I have routinely setup shots to a satellite that's the size of a volkswagon at 230,000 Miles using a 20M dish. It takes some time!
  • From looking at the pictures, they just used a parabolic dish antenna. You will get about 20-24db gain on one of those and it narrows the beam a LOT for that gain. So dont think anyone within 110km can log onto the network and lan away. This is a strictly point to point thing.

    Ive got two c-band dishes right now with a point to point network around town. The longest link is around 30km. if i dindt live in the mountains(of if i wanted to hike to the top of said mountains) i could get a link as far as the cur
    • For a cheap amp, you can buy 1 watt 2.4ghz amp IC's for very cheap. Here is a site that has a schematic and board layout for it.

      And very illegal in the US. Your not allowed to build your own gear unless your a Amateur radio operator operating in the Amateur bands. I'm willing to bet that Canada has the same kind of regs...

      • If you are an EE student in university or college here in Canada chances are you will end up building transceivers that operate on licenced FM bands, and they may or may not be legal, depending on the adherence to law by the prof, and his or her mood that day

        In other words, go to college and do tons of illegal stuff in the name of education :D

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