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Wireless Networking Hardware

5 km Range Commercial Wi-Fi Available 131

Posted by samzenpus from the connect-at-lunch dept.
prostoalex writes "Japanese company Maspro Denkoh will start selling transmission systems, enabling WiFi signal over 5 km, Network World magazine reports. From the article: "There are two types of antenna: one is a tube-shaped model about 40 centimeters long, and the other is a much shorter and square-shaped model. Combining two of the tubular antenna -- one on each end of the link -- will result in a transmission distance of about 5 kilometers while one of each antenna will work on distances up to 2 kilometers and two of the compact antenna will be fine for up to a kilometer, the company said.""
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5 km Range Commercial Wi-Fi Available More

5 km Range Commercial Wi-Fi Available

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  • Good for Home (Score:2, Interesting)

    by fodi ( 452415 )
    This'd be great for home, too, (if it's reasonably priced) because it would guarantee the highest bandwidth is available throughout the house, without any dead-spots, i.e. my wireless won't have to step down to 1mb/s when I'm at the other end of the house.
    • It would also broadcast your network 4.9 miles more than you need...
      • it would also broadcast your network 4.9 miles more than you need...

        Yes, but at the low low price of "The 5-km version costs ¥600,000 ($5,254)", you're getting the unheard of great value of just over a thousand bucks a kilometer. And who knows? Maybe one day you might just need one of those kilometers? And where would you be if you didn't have it, hmmm?

      • How? (Score:1, Informative)

        by Anonymous Coward
        It would also broadcast your network 4.9 miles more than you need...

        How do you expect an antenna that has a 5km range to exceed 4.9 miles? That's half again farther than it what it's range is.

        Repeat after me:
        KILOMETERS ARE NOT MILES!!
        KILOMETERS ARE NOT MILES!!
        KILOMETERS ARE NOT MILES!!

    • Re:Good for Home (Score:3, Informative)

      by eflanery ( 210795 )
      No, no it wouldn't.

      These are directional antennas, and directionality is achieved by focusing.

      If you used something like this for indoor coverage, you would have one small corridor of great signal, and more dead spots than you started with.

      If you want great indoor coverage use this stuff: http://www.andrew.com/products/trans_line/radiax/d efault.aspx [andrew.com]

      --e
    • What you need in order to move arround in hour house connecting to an AP is an omnidirectional antena (a pigtail that broadcasts in all directions.) This are directional antenas, that is, while the omnidirectional antenas cover 360 degrees, this only cover an specific range (it differs, it's arround 25 degrees for yagis, for example), but they have to be pointed to the other antena, and they require a line of sight.
    • If you measure area of your home in units of KM, then YOU THE MAN!
    • you would have a huge dead spot and just a short sector where it worked.

      it doesn't increase total power, rather focuses it on a smaller sector..
      and it costs an arm and a leg.

      if you want your house better covered buy couple of those wlan ap's that can extend each others range.. a lot cheaper than buying these antennas too.
    • Would you really want to sleep in the same room as an ultra high gain wifi antenna? I have (probably unfounded) concerns about upgrading my B to G as i sleep 100cm's away from the idea trasmitter location.

    • Re:Good for Home (Score:1, Informative)

      by Anonymous Coward
      I use a homemade corner reflector. I put my AP in the front left corner of my house and aim the reflector towards the right back corner and I get full coverage everywhere I need to. Yeah there's some dead spots, but it wouldn't be practical for me to be using a computer in that area anyway. I made mine out of cardboard and the aluminium stuff that roofers use. You can get a roll for a few bucks.

  • What would the FFC do? (Score:5, Funny)

    by Brent Spiner ( 919505 ) on Wednesday October 05, 2005 @10:21PM (#13726941) Homepage
    If this was $5,230 cheaper, and if the FCC wouldn't come after me with a sawed-off shotgun, I'd probably get one of these.

    • Perhaps the limits on transmitter antenna gain are less strict ... IN JAPAN!

    • Has the FCC prosecuted WiFi users for using non-stock, non-approved antennas?
      • They will if use becomes widespread.

        Actually, since it won't scale to become widespread, they probably wouldn't have to.

        Dense areas can't support this kind of thing for thousands of people in a square mile.
      • There's no need to proescute. Just the implied threat is good enough.
        Eg.

        FCC recieves complaints of wireless interference from someone.
        FCC says "Well, that band is unlicensed, tough."
        FCC recieves complaints of interference of licensed band from wireless source.
        FCC sends a fellow out with directional equipment, locates your AP, knocks on your door and says "Hi, I'm from the FCC. It looks like your running a illegal high-powered transmitter there. Care to turn that off? It's interfering with the hospital 3 b
        • Has the FCC even used an "implied threat" to take down illegal WiFi users?

          The FCC used to do what you described in the past, but from what I understand, that sort of enforcement has tapered off considerably.
      • That would be hard to do unless they are exceeding power or gain limits, or deploying a large number of such devices, since part 15 rules do allow use of non-approved antennas [akamaitech.net]. (I am not a lawyer or an RF engineer, so take this with a grain of salt.)
    • I seriously doubt that they'd care, since wifi cards transmit on frequencies unregulated by the FCC [wikipedia.org].
      • *rolls eyes* All frequencies are regulated by the FCC. Okay, maybe not once you start reaching the visible spectrum, but yeah, just because it's ISM doesn't mean it's not regulated. See that little sticker that says "Part 15" on it (at least here in Canada)? THAT means it's regulated. It's just UNLICENSED, which is what I think you meant. But yes, the FCC would care, if this stuff was anything special, which it ain't. Now, you take and put a 5-watt amp on your Dlink access point, and they'd be all over you

      • Re:What would the FFC do? (Score:1, Informative)

        by Anonymous Coward
        Unregulated != Unlicensed

        The FCC regulates all radio communications within the United States. Just because the frequencies that WiFi utilizes don't require a license (within a certain power level), doesn't mean you have free reign of the spectrum.

        BTW, this is perfect for amateur radio operators looking to extend their WiFi networks. Hey, we're licensed!
      • Wrong, they are "regulated", but not "licenced". Big differance.

        Above 300gHz (and below 3kHz), it is unregulated, and you can do whatever you want (probably won't be effective, given the nature of the bands, though). There are no restrictions on what is done, nor who does it.

        45mHz, 900mHz, 2.4gHz, 5gHz, 24gHz, and 60gHz (and some others) are regulated, but unlicenced. The FCC sets restrictions on what can be done, but not who can do it.

        Most other usefull frequencies are reserved for licenced (or military /
    • Didn't Verizon and SBC make a joint aquisition of FCC in 2000?

      Now that, my friends, is a super troll!!!

  • Yeah and? (Score:1, Insightful)

    by Anonymous Coward
    Can it serve decent speeds?

    I don't think anyone will care if it isn't at least half the power of broadband with a reliable connection.

    I would say that this article is nonsense, because it doesn't touch on whether or not it can actually scale to meet commercial demand, but that would give the impression that I didn't read the title, that being [...] Commercial Wi-Fi Available.

    On top of that, the summary doesn't even say where this is available, and whether or not it will be elsehwere. I'm left to assume this

    • Re:Yeah and? (Score:2, Informative)

      by Anonymous Coward
      What are "decent speeds?" 50+ Mb/s over 802.11a and 11 Mb/s over 802.11b are easily attainable at 5 km assuming line of sight. 802.11g typically isn't used for long distance links. Using yagi ("tubular"), patch ("square"), or parabolic grid antennas at both ends is standard procedure. Nothing new here.

  • Perfect! (Score:1, Funny)

    by Anyletter ( 875753 )
    Now I can leach off of all my neighboor's networks. We thought American's not using the wep or wap was bad now...just you wait.

  • So what, lots of other companies have done it.. (Score:3, Informative)

    by theobscurest ( 613689 ) on Wednesday October 05, 2005 @10:29PM (#13726983)
    Trango, Motorola Canopy, just to name a couple of proprietary solutions. Hell, I've even made a 16+ mile link with 802.11b SmartBridge radios. How do you think WISP's can go into and stay in business?

  • Nothing new here (Score:2, Insightful)

    by dorkygeek ( 898295 )
    Pringles can antennas [netscum.com] already delivered that back in 2001... Now, if there would only come someone along to pick up these pesky crumbs.
  • How exactly is this new? I've been using a fixed wireless ISP for well over a year now, and they've been in the area for at least two or three years before I started. Right now, I'm at 12km+ range from the main antenna and getting speeds comparable to local DSL at moderate range from a switch.

    Unless this new system is *dramatically* faster than what I've got now (Motorola Canopy), there's really no point.

  • As others have pointed out, sending a WiFi signal over distances greater than 500 feet is nothing special. I worked for an ISP in 2001/2002 that was doing wireless Internet service. At the time, Verizon did not give a rat's ass for doing DSL there, and the local cable company couldn't find their ass with GPS unit and a flashlight, so they didn't matter either. The longest distance we did was 15 miles, that was through high voltage electircal transmission lines (125,000 to 250,000 Volt range ones) and ove

  • 5 kilometres? All they are selling is a cheap yagi antenna and a cheap-as-free access point slapped onto the back of a network-enabled CCTV camera. You can build one from off-the-shelf components for less than $500, and that's Canadian dollars. Sure, you can up the cost by adding 'features' like CCD imagers instead of CMOS ones, a heated housing will run you another few hun, and if you want pan/tilt/zoom, that adds another grand. But fifty-two hundred bucks? Good grief! Furthermore, 5 km is nothing, as othe
    • ...don't forget! It's frequency AND power, not just frequency.

      See, I spend much of my driving time around 60W radios, but it's on 146 MHz. So I don't sweat it. Now, if it was 60W at 2.4 GHz...

      -shudder-
      • Yeah...I think I mentioned something about microwaves. Sometimes I do wonder about my ham buddies and their 1kW rigs, though, even at 2 metres...*grin*
        • A kilowatt at 2 meters. Brr.

          Y'know, seriously though. I can make it from Pensacola to Fort Walton Beach (35 miles) on 60 watts with an ITSY BITSY TINY LITTLE BITTY 5/8ths wave mag-mount. At 144 MHz.

          Explain to me why the local FM station needs 50 KILOWATTS at 99 MHz to make it clearly across the same distance? Hmmm?

          Oh, yeah, I know, I know, being able to listen to the radio inside buildings. WhatEVER.

          -grumble-
    • Your .sig loosely translates as "Recognised hidden equipment, sufficient not superior." Am I missing something? "Found unknown device?"
  • ... so desu - this is why you haven't been able to find a can of Pringles in Japan for the past two months!
  • Anyone have any info on power requirements or weight on this equipment?
  • 802.11b with parabolic grid antennas is possible up to 20 miles, if you get it high enough. Smaller anetnnas can easily go 5 miles at 11mb/s. This has been around for 5+ years, why did this story get posted?
  • I have been using a WiFi ISP for about 5 years now. And I am over 5 miles from the AP. A flat panel antenna with the tranceiver at the antenna. Cat 5e from the antenna to a router in the house. The antenna is transparent to me. They offer me T-1 if I want to pay for it.
    • Exactly. Tranzeo has been selling that stuff for years. Easy to use, cheap, and stable, too. Power-over-ethernet right to the radio unit, bob's your uncle. We use 2.4 and 5.8ghz units, vertical as well as horizontal polarization, at ranges up to 10 km, since they come pumping out 200mW. Configure the radio as an AP, a repeater, a client, or a bridge, it's all done in the firmware. This so-called amazing product (available only in Japan, so it must be amazing, right?) is NO BIG DEAL!
  • across 5km, Then post something under this comment. A system that can talk at 50Mbit+ at 3-5km ranges with power draws in the 5W range and low weight is something I would be very interested in hearing about. If you can post a web page link that would be good. A system that supports 802.xx standard is preferable.

  • Latency? (Score:3, Insightful)

    by Roguelazer ( 606927 ) <Roguelazer@nOSpam.gmail.com> on Wednesday October 05, 2005 @11:40PM (#13727289) Homepage Journal
    Correct me if I'm wrong, but wouldn't you start to run into increased latency issues over such a connection? 5km at 300km/ms means that you're talking, um, 0.016ms of travel time each way, per packet. While that does not seem significant, that's assuming perfect conditions (and my ability to do math in my head), and that could build up in the case of multiple transactions. Of course, considering that you're talking a minimum of about 30ms latency to any remote server, I guess it's irrelevant. Ignore me. :-)
    • Such speed-of-light latency would exist, as you say; and would be irrelevant due to other factors, as you say. What you seem to be missing is that that latency is present for _any_ kind of link. In fact, the speed of light in fibre (just to take as an example one of the more likely convential signalling media) is slightly less than the speed of light in a vacuum you used in your calculation. Ain't no way bits'll get from point A to point B faster'n light.
    • I remember reading something about special config being required for WiFi over long distances. It was a while ago, but I think it basically amounted to tweaking queue sizes/timouts in the base station, as WiFi wasn't originally designed for applications where speed-of-light latency would be an issue. I think that may have been for longer-range links, though, where it would be more of an issue.

    • You are correct that latency is an issue. For 802.11 especially, since each packet is acknowledged individually before the next one is sent (imagine TCP with a fixed window size of 1), you add 1 round trip time to the time to send each packet (at 11mbps, a 1500 byte packet takes about a millisecond and a half, and the acknowledgement takes a few hundred microseconds, so this isn't really a big performance killer).

      Another effect, though, is with transmission timeouts. Suppose station A sends a packet, an

    • As opposed to the instantaneous communication you get over fiber and copper? ;-)

      From memory, I seem to remember that propagation times for copper is about 2/3 the speed of light. (Meaning you get 50% more latency for the same distance.) So, for the same distance, wireless actually gets less latency due to physical propagation times than copper.

      In fiberoptic cables, the propagation time is the speed of light (maybe slightly slower since it's passing through the fiberoptic medium, I don't know). But since cab

  • Anyone surprised? (Score:5, Informative)

    by DeadBeef ( 15 ) on Thursday October 06, 2005 @12:31AM (#13727540) Homepage

    This is just a random press release from a company selling boring old wireless kit. There isn't anything special about getting 5km of range with off the shelf wireless gear,

    If anyone cares the math is not that hard to follow:

    You take the transmitter output power, subtract any loss in the cable between the transmitter and the antenna, add the gain of the anteana. http://db.osoal.org.nz/eirp-calculator.html [osoal.org.nz]

    Then you have to subtract the free space loss of your path ( the loss you get by putting the signal across the air ): http://db.osoal.org.nz/freespace-loss-calculator.h tml [osoal.org.nz]

    And finally you add the recieve gain of the receiving antenna, subtract the loss from the cable on the recieving end and compare with the receive sensitivity of your wireless receiver. I have bundled the rest of the calculation into this bit of javascript. [osoal.org.nz]

    For example, if I have two 2.4ghz radios that output 15dbm (32mw) that have a recieve sensitivity of -83db that are in waterproof boxes on the antenna mounting connected to two 22db antenna's 5km apart very roughly.

    15db - 1db + 22db = 36db or ~3981mw (just under the 4 watt max).

    - 121.65db for our free space loss

    + 22db - 1db = -64.65

    -64.65 is the strength of the signal received at the other end, fortunately the receiver has a receive sensitivity of -83 so we are in business. There is a link margin of ~19db to account for a little bit of noise, fade, solar flares, alien abductions etc.

    If you want more range, increase the power of the transmitter or the gain of your antenna. The government limits ( 4 watts for 2.4ghz, 250mw for 5.3ghz and 4 watts for 5.8Ghz in New Zealand ) are going to determine your maximum range barring some magical new wireless gear that has a better receive sensitivity.

  • I can make a 50km link using a night and day "top of the line" camera http://newsite.pagecomputers.com/store/product.asp ?catalog_name=Security+Devices&category_name=87g87 c453s1852&product_id=691230 [pagecomputers.com]
    ...and that includes instalation!
  • So what's the use of a 5KM transmission range in one of these fancy antenna if my little PowerBook can't crank a WiFi single back more than 500 feet or so?

    Then what?

  • I may the only person worried about this, but is there some sort of risk with having radiation exposure? I assume if 5-20 km (judging from other posts) range wireless is practical at reasonable prices and speeds, we're gonna have wireless companies competing much as cell phone companies do now. Is there are risk with 2-3 cell company towers and 1-2 wireless Wi-Fi towers blasting radiation at me? 24-7, 365? I mean, it sounds like that's where we're headed in some cities or even select suburban areas.

    • Re:Health Concerns? (Score:1, Informative)

      by Anonymous Coward
      Yes, you are the only one. (well actually no, but we won't talk about "them")

      These wireless things are very low power, in the U.S. 2.4 is limited to 1W (30dBm) transmit power. If we give these guys _way_ more credit than they deserve, and say their antenna is 20dBi (would be illegal by FCC standards, unless you cut the TX power to ~600mW; but what the hey, lets exagerate), which gives you 50dBm EIRP (100W). Due to the 3-dimensional nature of RF propagation, the power falls of as the inverse square of the di
  • Why do vendors focus on stronger transmitters, when that just results in greater potential for human brain frying. Imagine all your neighbours in a 5 block sky scraper community all sitting at home with 5KM transmitters! YIKES!!

    It is just as effective to create better receivers, that could for instance listen to signs from up to 5KM that even in large clusters would not fry your brain.

    Just a thought.
    • Because there are theoretical and practical limits. You can't pick up a signal that is totally burried in background noise no matter how good your receiver is.

      Also the 5 kilometers is with a directional antenna at each at. That's transmitting AND receiving. I highly doubt your are going to do anything to your brain with stuff anyway. Not unless you sit for hours on end with your head right infront of the transmitting antenna.
  • Just as a FYI, I currently use a wireless service that is supposed to do 1500 down and 382 up.
    Now, I live in Billings, MT and the weather around here isn't exactly great some times. Yesterday
    we had 9.08" of snow, my internet went down, along with power for about 2 hours, and to top it off
    the TV stations went west on some channels. After about 13:00 today everything cleared up.

    I will be switching to DSL via Quest, and Direct TV at some point.

    My point? Wireless access is great "if" the weather is fine, but
    • I'm also a wireless access subscriber. Are you on 5.8Mhz or 2.4Mhz? Your system isn't using Alvarion hardware by chance, is it?

      I notice my signal is better in the winter months, probably because foilage cover is way less here in Indiana.
    • Uh, if the power goes out, so will your adsl..

      Also, I'm not 100% but bad weather tends to hose my sattelite connection here (I'm on sky)
    • [i]Wireless access is great "if" the weather is fine,[/i] ... *and* you happen to have the fabled "line of sight", ie., live in a desert with no trees.
  • From what I can tell it must be something like this complete system [maspro.co.jp] for monitoring on a farm (Japanese). Maspro also sells home security video monitoring systems using some of the same components it seems. The article was a bit weak and since I haven't been to CEATEC today I can't tell you for sure but I'd be quite surprised if they are enjoying a 1000% markup like all the other slashdotters expect. That, plus it will "just work" and be durable, etc. Take a look at their export catalog [maspro.co.jp] (click on pdf lin
  • Now the whole neighbourhood can watch me download porn if I forget to turn encryption on!
  • They are talking about doing wireless over 5km distances when things like Wimax hardware is already doing 20km + or -. There is a company in Knoxville, TN and also in Phoenix, AZ that has installed and is starting to sell this extensive wireless service. http://www.wisight.com/ [wisight.com] If I'm not mistaken, the Wimax products offer 802.11G speeds at much great distances. So what is the big deal about this technology listed here.
  • The article describes combining the two antenna - one on each end of the link. Does anyone know if commercial manufacturers have looked into drastically varying the standard antenna shape or material. In my line of work, I study genetic algorithms and know that GAs have been used to design space antenna ( http://illigal.blogspot.com/2005/01/corkscrew-sha ped-space-antennas.html [blogspot.com]) that are far more effective than current designs.
  • The noise floor in any city is just way to high to use 2.4 units with any sort of reliablity.. sure maybe 5 yrs ago this was fesiable but today.. with every laptop having 802.11b/g, all those Linksys/Dlink units flooding the market there is way too much interference.. the frequency levels are limited.

    As an WISP, this is the exact reason we are ripping out all the 2.4 equipment, it's pretty much useless now.. you can only get a reliable like like 500ft from a tower (which is pretty shitty). this is amped and
  • What happens when a few WiFi nodes are positioned in the line of the narrow AP beam? Do they progressively block the signal to the next nodes in line? How many nodes can line up behind each other to receive the signal? Just one, for a mere "PPP" connection?
    • What happens when a few WiFi nodes are positioned in the line of the narrow AP beam?

      The important quantity is the ratio W^2/Lamda, where W is the size of the object (obstruction, receiving antenna, sending antenna), and Lamda the wavelength (about 0.12 m at 2.4 GHz). This is an indication for the distance over which the beam profile is smoothened out due to diffraction. For W=1 m, the shadow will be negligible after 8 meters. (For a narrow laser beam, W=3mm, Lamda=600 nm, the distance is 15 meter).

      The q

  • http://www.oreillynet.com/cs/weblog/view/wlg/448 [oreillynet.com] Hmm... A tublar antenna on both ends... Sounds familiar...

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