Follow Slashdot blog updates by subscribing to our blog RSS feed

 


Forgot your password?
Close
typodupeerror
×
Hardware

Non Line of Sight Broadband 168

Posted by CmdrTaco from the wouldn't-it-be-nice dept.
gfilion writes "IEEE Spectrum has an article about nifty wireless adapters that don't require LOS. At first, NLOS wireless may not sound like a big deal. After all, ordinary radios and cellphones are non-line-of-sight devices. But they don't carry broadband data. What makes the latest generation of NLOS wireless technology worth talking about and having is that it delivers data at high rates over substantial distances."
This discussion has been archived. No new comments can be posted.

Non Line of Sight Broadband More

Non Line of Sight Broadband

Comments Filter:
  • Actually, FM radio is line of sight.
    • Really? Then how come I can receive FM radio in my basement behind cinder block?
    • My FM radio works inside a tunnel...

      I'm curious why you made that comment. Don't worry, I'm not assuming you're a dumb ass, I'm assuming you know more about it than I do and was hoping you could explain a little more clearly what you meant. :)
      • When "line of sight" is used for FM stations it means that the signal can only carry to the horizon. Meaning your radio station would can only broadcast as far as you can see from the transmitter. This has to do with the type of wave, the fact that the earth is round, and the atmosphere. There are several website that discuss this. Search google for it.

        I hope that this clears up some confusion.
        • I hope that this clears up some confusion.

          Yes it does, thank you. :)
        • Let me clear things up some more.

          First, FM is a modulation mechanism; many frequencies only propagate through the ionosphere under rare conditions. This includes the VHF (30MHz-300MHz) used by FM radio and much of TV.

          However, VHF is substantially propagated by diffraction and refractive modes. I receive a VHF TV station regularly which is on the other side of a mountain from me.

          High bandwidth technologies often require line of sight because other propagation modes create "multipath"-- there are multiple paths that provide nearly equivalent signal strengths. This smears bits together. The bandwidth of what you're expressing limits multipath from being such a concern for FM radio-- to express an audio signal that is mostly under 10KHz, as long as the paths don't differ by more than .00001 seconds, multipath is irrelevent. And the speed of light is pretty darn fast.
      • Your FM will work but AM probably doesn't. You recieve FM in a tunnel because it acts as a wave guide, much like TV coax cable. AM wavelengths are much longer and most tunnels won't support a propogation mode. So although you can't "see" the broadcast antenna from your car, the entrance to the tunnel can.
        • I noticed that AM goes out in tunnels, damn near brought it up heh.

          So are you saying that the radio wave enters the tunnel and then bounces around? If so, that explanation is better than the 'radio passes through concrete' explanation I got a couple of posts ago.

          • So are you saying that the radio wave enters the tunnel and then bounces around? If so, that explanation is better than the 'radio passes through concrete' explanation I got a couple of posts ago.

            Different frequencies are blocked or impeded by different substances, depending on stuff like wavelength. For instance, microwaves are heavily attenuated by water, so a rainstorm can degrade the transmission

          • Without getting into the nitty gritty details, it's kinda like that. Think of light traveling down a fiberoptic cable. It's not really the same but a similar idea. Although most of what you see in a tunnel is concrete, there is undoubtedly a lot of metal hidden from view, rebar in the concrete for instance. This allows it to act as a "electromagnetic pipe" commonly called a waveguide.

            EM will pass through concrete at these frequencies but most tunnels are built to go under something, and that something usually reflects or absorbs a large portion of the wave.
    • Actually, FM radio is line of sight
      Um... what's YOUR definition of Line of Sight? Because it doesn't appear to be the same as everyone else's definition. (Unless of course, you can "see" radio waves with your eyes!)

      If you read the entire article, you would have read:
      "LOS systems rely on a high-power transmitter at the base station, an unimpeded line of sight between transmitter and customer, and a highly directional outdoor antenna at the customer premises, ..."

      How would you explain people being able to listen to a radio in their house/apartment/dorm-room? (And don't go telling me that "the radio signal goes in through a window and bounces around your house until it finds your radio antenna", because it just isn't true.)

    • Re:ordinary radios ...are non line of sight (Score:5, Informative)

      by Lumpy ( 12016 ) on Thursday June 06, 2002 @01:28PM (#3653428) Homepage
      Not. not by a long shot.

      FM is Frequency Modulation. it is a mode of transmitting. what you are talinkg about FM or the 88-108Megahertz broadcast band, is not line of sight. that low of a frequency has both ground waves and sky-waves. this is how in west michigan I can recieve WLUP Chicago on 97.9MHZ easily by swinging a directional gain antenna in that direction. Also, Frequencies from 88MHZ up past 450MHZ also can take advantage of tropospheric ducting.

      Line of sight doesn't start until past 1.2 GHZ 802.11 equipment at 2.4ghz act like line of sight outside because of water vapro and water bearing items (leaves, squirrels, children) suck up large amounts of signal..

      so NO FM is not line of sight. not in the correct term nor in your definition.
      • The reason why the 3 meter broadcast band seems like its everywhere is because a lot of stations are running out like 27,000 watts (or much more in some cases) - it would be interesting to see what path the signal takes to get to your radio. If broadcast companies used lower powers I'm sure you'd notice a big difference in propagation. Here in Oregon its hard to hear most Portland stations after you drive west on sunset highway over the Cascade Range. Anyhoo - I've seen line of sight make a big difference on all the vhf/uhf/shf bands. 70cm band for instance seems highly reflective to trees, rain, hills etc. The 2m band seems to be less prone to that sort of thing, but trust me it still exists.

        Also vhf/uhf ducting is a pretty rare occurance - I only seem to hear it happening a few times a year - like when you get the chance to talk on a repeater thats way up in Canada (done that) when you normally can't.
        • It's rare in some areas, while it happens on a monthly basis here in michigan. As for how the radio waves propagate... Buy a book called the ARRL handbook. it will teach you everything there it to know about radio wave propagation. and to get the level of Ham radio license I have you need to know it along with almost everytinhg about radio. Get that book and the ARRL antenna handbook.. they are the only two real refrences about radio propagation and reception on the planet that are readable.

      • FM broadcast may or may not be line-of-site...I am not 100% sure. However, you contradicted yourself in your post...antennas with directional gain, such as a Yagi, are mainly used for LOS communication.

        I do not that 2 meters is primarily LOS, which is just slighly higher than broadcast at 150 MHz.

        Another thing I am not sure of is whether or not the mode comes into play or not.
        • Actually, antennas with directional gain are very often used for non-LOS propagation.

          For example, KGO radio, a 150,000W AM station in San Francisco, CA, has an array that is designed to propagate the radio waves up and down the west coast, and not into the mountains to the east or to the ocean to the west. Reception in northern Canada of the KGO signal is not uncommon.

          Amateur radio operators often use high-gain antennas for non-LOS propagation modes, as long as the high-gain antennas for the given frequency are of a reasonable size. (Obviously, a directional antenna on 1MHZ, with a 160M wavelength, would be rather large).

          It is true that exceptionally narrow-bandwidth antennas, like parabolic dishes, are generally only used for LOS or reflective propagation modes. However, low-element yagis are routinely used for ionospheric propagation, tropospheric ducting, ground-wave propagation, etc.
      • Tropospheric ducting is when a little duct opens up in the troposphere to allow all the radio waves through, lisa.

      • Line of sight doesn't start until past 1.2 GHZ 802.11 equipment at 2.4ghz act like line of sight outside because of water vapro and water bearing items (leaves, squirrels, children) suck up large amounts of signal..

        We're talking about electromagnetic radiation. Forms include "radio", "tv signals", "light", and "X-rays". It's all one phenomenon.

        None of these is "line of sight". (Catch the paradox? :-)

        They all bounce off some stuff, get diffracted by different stuff, and pass through still others.

        So in our normal world FM radio waves tend to go "line of sight", but pass through several meters of concrete without problems. Mountains are a problem though. (try seeing through a mile of fog: you can see fine for several tens of meters, but a mile becomes a problem). But FM radio also bounces off some atmospheric phenomena.

        Somewhere beyond 1GHz, you get less of that bouncing off the atmosphere, and more and more absorption by water (remember the fog example?!).

        Roger.


    • Modulation schemes have nothing to do with whether a particular transmission is line-of-sight or not. Carrier frequency does. I assume by "FM radio" you mean commercial broadcast FM as in 88-108 MHz. Why then was I receiving 96.5 WFLB (which is in Fayetteville, NC) in Richmond, VA the other morning (which has a 96.5 of its own)? Hint - Tropospheric Ducting (or tropo-ducto, as I call it, since it's nearly indistinguishable from magic - presto-chango and all that).

      In general, as frequency increases, so does the line-of-sight nature of the RF. Light, being extremely high frequency RF, is very much line-of-sight. AM Radio, being between 540 kHz and 1600 kHz, can span the globe because of groundwave bending and ionospheric ducting. Amateur radio operators deal with lots of different propagation modes all the time.

      • Another thing guys is like TV, Radio waves also bounce off into Space, granted were talking AM/FM here, but their signals go anyway it can, up, down, left, right, and everyway inbetween. I feel reduntant adding this, but I didn't see it mentioned yet and hopefully will get the story striaght that radio is deffinately NLOS.
    • The best way of saying it...

      FM radio is more line-of-sight than is AM radio. But of course line-of-sightedness is a characteristic that has absolutely nothing to do with the modulation method but everything to do with carrier frequency. The higher the frequency, the more line-of-sight it is. Consider light, which is very line-of-sight.

      FM = Frequency Modulation in which information is encoded by varying (modulating) the frequency of the carrier.

      AM = Amplitude Modulation in which information is encoded by varying the amplitude of the carrier.

    • Mod this up (Score:2, Informative)

      by metatruk ( 315048 )
      Wiredog's right.
      FM broadcast radio, as well as cell phones, and broadcast television work in the VHF and UHF bands.
      Because of the frequency of the carrier wave, these bands propagate using line of sight which means that the signal's means of propagation are not by reflecting off of something such as the ground or sky.
      Lower frequencies, such as local AM broadcast use ground wave propagation, because the signal reflects off of the ground.
      Short wave radio tends to propagate using sky wave propagation, because the radio signal bounces off of the earth's ionosphere. This is often refered to as "skip" and can cause signals to travel across the globe.
      • Just one question-- if reflection is not of concern, why is multipath such a concern when it comes to vhf and above radio frequency reception?

        See this for some cursory information on how diffraction works as a propagation mode for VHF and above. It is not uncommon for the TV signals, etc you receive to be on the other side of a mountain. And reflective propagation modes are -heavily- used to obtain cellular coverage in urban areas.

        http://www.crc.ca/en/html/crc/tech_transfer/1017 1

  • Now if.. (Score:1, Offtopic)

    by ImaLamer ( 260199 )
    Only if they had this for the people in the last story they could not have had to lay so much fiber.

    • Re:Now if.. (Score:2, Interesting)

      by msl521 ( 468252 )
      Per household reached, its always cheaper for a wireless solution than a wireline system. Of course that return doesn't start happening until you've got quite a few people buying your service.

      It costs on average about $1000-$5000 per home passed by cable. So you can start out building your network small. Or you can spend several hundred thousand dollars to over a million to build a TV station and reach a whole city.

      Michael
      --
      The opinions expressed above are those off one side of my brain, the other side and my employer may not agree.

  • rural areas (Score:2, Interesting)

    by TweeKinDaBahx ( 583007 )
    This is especially good for people like me, who reside in rural areas. One of the biggest bottlenecks on geting broadband up in the mountains is the fact that trenchs are expensive to dig (damned granite) and that there is no line of site.

    Hopefully something useful is done with this and some committee in congress doesn't deem it a threat to 'homeland security'.
    • well then according to EchoStar merger [echostarmerger.com] if they get approval they an provide broadband to everyone in the US
      • Oh good. Us Canadians can pirate American ISPs too :)

        Not that I'd need to, as most communities in my province have broadband, but still.
    • Not likely. The technique in the article relies on the fact that the signal will be bouncing off of various solid objects such as cars, buildings etc. It's not going to help you get over a hill or through trees (which mostly absorb rather than reflect).

  • getting my life back (Score:5, Funny)

    by orcldba ( 195785 ) on Thursday June 06, 2002 @01:14PM (#3653324)
    Finally I can take down my tent under that tower and move in with girl I really love.

    • Finally I can take down my tent under that tower and move in with girl I really love.

      When you brought the personal impact of this new technology into focus for us, my first reaction was one of happiness for you. But then I started wondering how you would break it to the one in the tent? I hope you have planned something less blunt than, "Sorry, you're not the girl I really love." We need to be cognizant of the human costs of new technologies. You should at least leave the tent up, I think.

  • Noone wants broadband? (Score:5, Interesting)

    by Enry ( 630 ) <enry@@@wayga...net> on Thursday June 06, 2002 @01:16PM (#3653333) Journal
    What if you built a network and nobody came? The February 2002 FCC report also cited a survey from the Strategis Group (Washington, D.C.) that found that only 12 percent of on-line customers were willing to pay $40 per month for high-speed access, a number that rose to only 30 percent when the price was dropped to $25 per month.

    That's really strange. Doesn't AOL cost $30/mo already? What this apparently says is that even though users can have 24x7 net access at a higher speed that doesn't tie up their phone line for a lower cost, they'll stick with what they have.

    Who paid for the study, Disney?

    • When offering staff here a better webmail client, more than 50% said they would rather stick with what they have than to change. With training included, and additional features explained, I might add.

      Saving $5 a month but having to learn a new interface, change email, or any other impediment, will stop a large number of users who read maybe 2 sites a week and read email on a non-daily basis. Broadband as a business model is shaky to say the least. Those consumers who want it happen to be those that are least wanted as consumers by the ISPs. Their cuddly minimal use people will be tying up modem pools for decades to come.

    • And of course the <SARCASM> WONDERFULLY INTELLIGENT AND FRIENDLY CUSTOMER SERVICE/TECH SUPPORT REPS </SARCASM> have NOTHING to do with the lack of people getting/staying with broadband. I know when MYcable modem was going out DAILY from 2pm-6pm they <SARCASM>rushed right out to fix it!</SARCASM>
    • From the article:

      Outside of playing interactive games, which is hardly a universal activity, no broadband "killer app" has yet emerged.

      I don't know about you, but isn't quickly pirating movies and music a KILLER app? If I had broadband connection like my brother, I would probably have a collection of 200 some movies too.

      So what's the real reason? You have a killer app, and a low price in some areas, yet only a fraction of people are subscribing to it? Something is fishy...
      • Yeah absolutely, but it's not as universal as all that. Some people just don't ever own physical copies of music, happy with duff quality AM radio, and never go to the cinema and all that

        Most people want email and web access. I bet a lot of that is for occasional porn, too... statistics somewhere probably suggest that.

        I think that for some low usage types, broadband adds nothing to the experience. If they have to wait 2 or 20 minutes for that one mp3 they download a week, what does it matter? They're probably online for a 30-40 minute session anyway.

        HDTV hasn't had a big pickup either. A killer app won't be just more speed, but something completely new available. Most people who want good movies are perfectly happy to subscribe to cable or rent, rather than the hassle (and it is a hassle) of downloading movies "for free (not)" from the 'net.

        The true broadband usefulness I see for corporate WAN and teleworking. Can't see it being useful to the home user who doesn't do much with the 'net in his/her home. Just those who are already pushing their modem to its limits and staying online forever. Chat users with no local call fees wouldn't get broadband anyway, unless they are big DCC users.

    • I work for an ISP in a rural area. People call up all the time because they signed up for AOL and then they got their first phone bill and... you know the rest. But quite a few actually insist on keeping their AOL service even though we provide the same thing but without the flashy software with the "you got mail" WAV file. So they're will to pay us $18/month and whatever AOL is charging for an outside ISP account now ($10?).

  • Am I the only one that's tired of radiation? (Score:5, Interesting)

    by green pizza ( 159161 ) on Thursday June 06, 2002 @01:17PM (#3653358) Homepage
    Ok, I'm not scared enough to wear a tinfoil suit... but I'm somewhat worried about the rapid growth of wireless gear, especially those gizmos that brag about their ability to trasmit thru almost anything. Is there a point where our wireless usage will begin to cause some damage to the human body? That's a lot of energy zipping around every which way.

    I know nothing about this field... but I am curious.
    • Better not go outside. There is the daystar thing some people refer to as the "Sun". This Sun emits tremendous amounts of radiation all across the spectrum. Fortunatly the stuff in the high spectrum is absorbed by the Ozone layer, but most of our radios operate at much lower frequencies than that. Be careful though, if you spent too much time in line of sight of the sun, it can actually burn your skin!
    • Stop listening to media hype!

      It's all very low power (less than 1 watt) and you should be fine, just make sure you keep the antenna pointed away from your head. Now, if it was a big 100watt transmitter you would have something to worry about. If you're really, really nervous the FCC recommends you only broadcast for 6 minutes at a time.

      You're much more likely to get killed trying to make cellphone calls whilst driving.
      • So its low power. If concentrated into a small point, 100mW can do its damage. You can burn yourself (as in smoke from the skin) with a 1 watt signal by lightly touching the tip of an antenna.

        What happens to human flesh when the power increases? A CB radio puts out 4 watts and it can put the burns much deeper into the skin when contacted. That may be an example of a lower frequency, but higher frequencies such as microwaves, can be accidentally "focused" much like the sun with a magnifying glass. You can catch something on fire across the room (or set ablaze the tires to that black van parked across the street) by attatching a directional 2.4GHz antenna to the waveguide of a microwave oven.

        A few hundred milliwatts here, a few hundred there, who's counting? Pretty soon, we won't need jackets in the winter.
        • What a troll! A 1 Watt radio burn, as if. 1 Watt will not burn no matter how much it's focused. As for a microwave oven, they use a hundreds or even a thousand Watts. That's how they heat food.

          How about that nasty burn you get from a 60 Watt light bulb? Or have you ever watched toast burn in an oven? That's RF baby. Radiated heat is RF.

          The cool thing is that thanks to the inverse square rule, the energy levels drop off pretty quick as you move away from the source. That why the light bulb is hot if you put your hand near it, but it's not from a few more inches away.

          Perhaps you need to learn the difference between RF heating and ionizing radiation. One is dangerous, the other isn't any more deadly than a hot light bulb.
          • You better believe that you can get burned off 1 watt. Milliwatt laser diodes burn tiny pits into cdroms, one watt RF energy can burn away a small patch of skin in short time.

            You appear to have read too much thoery and not have worked with antennas too much. If the wavelength is small enough, it indeed can be focused.
            • Last time I checked, a LASER isn't actually classified as a radio. We we're discussing RF burns, and while light is, of course, RF, it's not what we were talking about, which was Radio.

              Also, I didn't say RF couldn't be focused. ALL RF can be focused, What I said was that 1 Watt wouldn't burn no matter how much it's focused. The statement was in relation to RADIO, not light or ionizing radiation.

              I work with antennas all the time, I'm a licensed ham and I operate everything from HF to 10GHz. I know of what I speak.
    • Comment removed based on user account deletion
    • This wireless network gear (at least the unlicensed stuff) is VERY low power (typically in the mW range). I'd be more worried about commercial radio and tv stations, ham operators, cell phones etc. I wonder what the effect of a subway full of commuters all with cell phones is anyway.

    • "especially those gizmos that brag about their ability to trasmit thru almost anything"

      I'd worry more about the ones that can't transmit through stuff - if the evil rays went straight through your body that's fine, but if they don't go through that means they're trapped inside you!

      Cheers, Paul
      Calling people 'mate' since 1991

  • Skip! (Score:2, Funny)

    by Salden ( 571264 )
    Wow, now I can blow the dust off of my Antron-99 and 40 foot mast. And during the day, I may be even able to lower my routes with skip!
    • Not sure you'd get EHF out of an Antron-99 - the standing wave ratio would be off the meter. Still, with a 500watt "burner", you might get some distance out of it ;)

  • My house is encircled and enshrouded by a dense cover of mature mapple and walnut trees, such that I'm unable to mooch off my company's wireless internet because there is no line of sight and the trees degrade the connection so badly that it's not even worth trying if there were.

    Once this comes down in price(I'm guessing it's still semi-expensive since it's newer technology) it will be great for all the rural areas out here in the sticks.

    A friend that owns an ISP in this area already has plans in the works to create a 802.11x grid in the areas surrounding my town in order to provide high-speed access to the farmers and very small towns(less than 50 people) that don't have any form of cable or dsl. So far the only hang-up has been the construction of towers in the void areas where there are no grain bins or elevators tall enough out in the areas where an access point and repeater is needed. Judging by the information provided in this article he may be able to skip out on some of these towers due to the greater distance provided by the NLOS technology.

    • I hadn't thought of that. Compensate for insecure WEP with a bunch of maple trees. Restrict the signal to your yard.
    • There's a high-tech device you can buy which will help with that problem - it's called a chainsaw ;)
    • You aren't very clever then. Raise an antenna over the top of the trees somewhere, either a small one bolted to a high limb somewhere, or if the trees aren't so tall, put up a 30' pole or so. Run a line down from it, and buy some conduit to put it inside the house.

      Only the antenna itself has to be outside the blockage.
      • You aren't very clever then. Raise an antenna over the top of the trees somewhere, either a small one bolted to a high limb somewhere, or if the trees aren't so tall, put up a 30' pole or so. Run a line down from it, and buy some conduit to put it inside the house.

        Isn't that going to bring 1.1 gigawatts into your house during thunderstorms? Handy for running flux capacitors, perhaps, but not so good for electronics.

      • You haven't seen my yard or neighborhood. I'm not talking about a few trees here. My yard is more like a forest in the amount and height of mature trees. Most of the trees are well over 50' tall, and those that aren't that tall provide foliage that provides an even better horizontal wall. Add to that the hedge of lilac bushes around the perimeter of the yard, and the large amount of trees in the neighbor's yards and you have not only a large amount of very nice shade and pretty decent privacy, but also a veritable fortress when it comes to getting any form of line of site.

        A 30' tall would do little to no good since the trees range in height from 6' tall (lilacs), to 20' (smaller maples), to 50' (largest maples and walnuts). The foliage from all of these trees creates a pretty good area of blockage on both the horizontal and vertical planes.

        If I put the antenna up in a high up limb of one of my trees, then the neighbor's trees would do an equally adequate job of blocking the LOS. Also of note is that I don't live in a large city where lots are only marginally larger than the house itself. To reach the edge of my property with antenna cabling to reach an antenna would require a cable that would loose enough dB of signal strength such that the antenna would have to have a pretty high gain on it in order to counteract this. The only other option would be to actually put the access point itself up in the tree, but then I run into the issue of powering the unit, which I suppose is possible via PoE, but generally tends towards being a higher cost of ownership, not to mention digging up my yard to run cable up a tree, which generally defeats the purpose of being 'wireless' in the first place.

        • I'm no expert, but if you get the antenna even a few feet above the canopy, that would be enough, wouldn't it?

          As for defeating the purpose of wireless, I think you may have missed the point. The point is getting broadband access, not the fact that you can get it wireless, right? Personally, wireless is only good for my iPaq, and to a lesser extent, my laptop. Put up your own cheap WAP, if that's what you want.

          Someone addressed the whole lightning risk thing... again, I'm no expert, but aren't there decent ways to fix this?

          Signal loss is a big issue, not sure how I'd handle it. If you're talking cat5, that means you're within 100 meters, which is plenty close to not worry about this. If it is indeed too far for cat5, it's still unlikely to be too far for whatever coax is appropriate for this, is it not?

          As for running conduit, you're only talking $1.50 per 10ft... I just checked at Home Depot the other day. It's shitty work, but only ever has to be done once.
    • The technique in the article relies on the fact that the signal will be bouncing off of various solid objects such as cars, buildings etc. It's not going to help you get over a hill or through trees (which mostly absorb rather than reflect).

      As someone else mentioned, in your case the solution is to either get your antenna up higher or make your trees a lot shorter :)
  • i sure would like this for my parents. they live in the middle of Honolulu, yet they are too far from the nearest DSLAM, and we would need to dig a trench to bring cable from the sidewalk to the house. no wires can simplify things a great deal.

    the article didn't mention the speed, but compared it to Bluetooth. would that be fast enough for video and voice?
  • man, if 802.11b is already out of control, this is just going to be rediculous. So much data flying through the air. I just need an antenna, a NLOS NIC and a nice packet sniffer. I could rule the world!
    • > I just need an antenna, a NLOS NIC and a nice packet sniffer. I could rule the world!

      ...and I just need to encrypt my data.
      Have you ever heard of encryption? :)
      Transmitting non-encrypted data over the air is stupid.
      Well, but there is a lot of people that do stupid things, out there ;)

  • TV (Score:3, Insightful)

    by wowbagger ( 69688 ) on Thursday June 06, 2002 @01:35PM (#3653461) Homepage Journal
    Excuse me, but TV is non-line of sight, and moves a lot of data (precious little INFORMATION, but that's another rant).
    • Excuse me, but TV is non-line of sight, and moves a lot of data (precious little INFORMATION, but that's another rant).

      Yes, but TV is a one-way street (ie - shouting at it doesn't do you any good)

    • Re:TV (Score:1)

      by nmos ( 25822 )
      TV is one way and uses MUCH higher transmit power.
  • Many wireless providers using 3G networks outside of the US provide fast data access through their non-LOS devices, and I agree with the other poster that TV and now Digital TV move large amounts of data through non line of sight methods as well. My Apple WAP does non-LOS, albeit at a relatively slow rate and shorter distance.
  • "maintaining an adequate signal-to-noise ratio would require a service provider to install a transceiver base station every 50 meters, a proposition that would appear to be prohibitively expensive"

    50 meters? Hmmm...

  • WTF? (Score:3, Interesting)

    by uslinux.net ( 152591 ) on Thursday June 06, 2002 @01:44PM (#3653512) Homepage
    The February 2002 FCC report also cited a survey from the Strategis Group (Washington, D.C.) that found that only 12 percent of on-line customers were willing to pay $40 per month for high-speed access, a number that rose to only 30 percent when the price was dropped to $25 per month.

    Huh? I pay $21.95 for 40Kbps dialup access and $22/month for a second phone line. I'd sure as hell pay $40 a month for HIGH SPEED access. In fact, I'd pay double that without blinking. Right now I'm looking into frame and 802.11 solutions, but I have trouble stomaching $550/month for T-1 speeds, and I've had only minimal luck finding people who are interested in $50/month colo (hey, if you're interested, e-mail me). All I want is high speed, no restrictions on running VPNs, and low latency (so I can use ssh).

    And frankly, it seems MARKETING is the real problem. If you offered $20/month dialup users access which was 2.5 times their existing speed for the same cost, they'd be crazy not to take it. So, MARKET it at 128kbps for $20/month, $30/month for 256kbps, $40 for 512kbps, etc. Bandwidth is like a drug - once you realize what you can do with it, you always want more. Maybe people aren't interested in paying $40/month when they spend $20 and use a computer 30 minutes each week, but if you get them in the habit of sitting down whenever they want to look something up, find a recipe, phone number, etc, they will soon *realize* what benefits a permanent, high speed connection have. Heck, think how many trees the phone company would save if everyone used the internet to look up phone numbers, and they stopped printing phone books.

    • You're forgetting about the part where they make a ton of money off of the advertisements. Ever look at how many attorneys take out full page color adds?
  • We're [beamreachnetworks.com]well along with our product. We'll be Virginia doing field trials with Verizon next month.

    The highlights: non-line of sight, near symmetric T1 speeds to the home user, VOIP, low latency, and adaptive beam-forming. If you're too far for DSL or cable, check us out.

  • For anyone in the San Francisco Bay Area, take a look at Gatespeed.com. For those of us too far from the CO for DSL, where cable modem service isn't available (if you even wanted it), but still want 256k symmetrical or better, check them out. They had it up and running 4 days after I called them to ask about prices and availability. And it costs about the same as IDSL. They'll also give you static IPs, and don't mind if you actually USE the bandwidth you're paying for.

  • Check out WaveRider Communications [waverider.com] LMS4000 900 MHz Modems. We've been selling broadband NLOS systems for over a year, with thousands installed. At 2.75 Mbps raw data rate (up to 1.96 Mbps FTP's!) and a range of up to 10 km in rural areas, they are a great solution (I may be biased, being one of the engineers who designed it). Even better, the majority of installations are indoor, with an antenna mounted by a window, and can be done by the customer.
  • Sprint has field trials going using technology from IP Wireless [ipwireless.com] and Navini Networks [navini.com] [Annoying Flash].

  • I want MURS (Score:3, Interesting)

    by anthony_dipierro ( 543308 ) on Thursday June 06, 2002 @06:52PM (#3655937) Journal
    Unlicensed NLOS with a range up to 20 miles. [provide.net] Only supports 14Kb/sec or so, but that's all CDPD supports, and it costs $30/month. Now why hasn't anyone come out with cards running on MURS frequencies? I sure would buy one.
  • Call me when they package a troposcatter antenna in a PCMCIA card..
  • I've been a big fan of NLOS wireless for a couple years now. I wish the article had mentioned my favorite wireless vendor, a Canadian company called WaveRider [waverider.com]. They have been designing and building LOS and NLOS systems for several years, including ones that are customer-installable (no "truck roll" cost). Their staff is friendly and their service is first rate, and no I don't work for them.

Slashdot Top Deals

E = MC ** 2 +- 3db

Close