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Australia Networking The Internet Wireless Networking Technology

Australia's Outback Could Get Web Via TV Antenna 121

Posted by Soulskill from the hope-they-broadcast-the-sites-you-want-to-see dept.
disco_tracy writes "Australia began switching off its analog TV signals in June and the transition to digital-only transmission is expected to be complete by the end of 2013, five years before the roll out finishes for the NBN. The leftover analog spectrum could be used to deliver Internet to people living in remote areas. Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were."
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Australia's Outback Could Get Web Via TV Antenna More

Australia's Outback Could Get Web Via TV Antenna

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  • It's the idea of the future! (Score:5, Funny)

    by PhrostyMcByte ( 589271 ) <phrosty@gmail.com> on Tuesday December 07, 2010 @02:25AM (#34470712) Homepage

    Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

    Gentlemen, I think we've found our solution. With 4G, we need to first convert the digital signal to analog before transmission. Network congestion will be a thing of the past!

    • Re:It's the idea of the future! (Score:5, Informative)

      by butlerm ( 3112 ) on Tuesday December 07, 2010 @02:35AM (#34470756)

      Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

      I think someone needs to gain an acquaintance with the Shannon Theorem [wikipedia.org].

      • Re: (Score:2)

        by toastar ( 573882 )
        But I don't know how to juggle.

      • Re: (Score:2)

        by nzac ( 1822298 )

        I think there is just a huge amount of Bandwidth that was allocated for the analogue tv spectrum, thus the main limitation required transmission power which can be bought as cap. Also the receiving technology is already installed.

        This would be even more effective in a rural environment as there would be fewer people in range of each antenna.

      • The premise here is that the people aren't sharing the same bit of bandwidth. These localised towers will deliver signals at short range to very disperse locations. It's a shitty worded summary but in essence what they meant to say is that rather than sharing the same bandwidth where each additional user will slow it down for the rest as the signals are multiplexed, each user gets his own dedicated slice. Works well in the country where the population is disperse, the antennae are directional, and there's a

        • Re: (Score:2)

          by dynamo ( 6127 )

          Yeah, right, TV won't have the same problem 3G has where it sends the same information to everyone in a wide broadcast - because TV was the one that used localized cells to re-use the same bandwidth. Huh, I guess the rest of the world had that backwards.

          • No you're missing the point. TV has infrastructure in place at all the endpoints, all you need to do is add antennae to a tower. You ever lived in the country? I remember my mobile phone purchase a few years ago. $200 for a mobile, and $450 for a boosting antenna so I could even get a signal, plus a guy to come out and align the equipment. Fortunately I lived in one of the few towns where this was even possible. UHF frequencies travel further with far less power output. 3G internet is neither feasible nor c

      • Re: (Score:2)

        by c0lo ( 1497653 )

        Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

        I think someone needs to gain an acquaintance with the Shannon Theorem [wikipedia.org].

        Shannon's Theorem deals with the information rate in time... when adding the spatial distribution to the equation(TFA: "nanopeople/sq.km"), there may be a solution assuming a rarified enough spatial/angular distribution (and, of course, enough transmiting power).

        Are we goint to see another patent for CSIRO? (at least they worth it)

    • Re: (Score:3)

      by Shag ( 3737 )

      It works just fine, as long as everyone views the same web page at the same time.

      • It works just fine, as long as everyone views the same web page at the same time.

        Or maybe someone could do an optimized bit torrent client :)

    • Re: (Score:2)

      by c0lo ( 1497653 )

      Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

      Gentlemen, I think we've found our solution. With 4G, we need to first convert the digital signal to analog before transmission. Network congestion will be a thing of the past!

      Yes, of course... But with one catch: need to keep the population density to "nanopeople per square kilometer".

      • Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

        Gentlemen, I think we've found our solution. With 4G, we need to first convert the digital signal to analog before transmission. Network congestion will be a thing of the past!

        Yes, of course... But with one catch: need to keep the population density to "nanopeople per square kilometer".

        In Australia, we can almost do that.

        • Re: (Score:2)

          by c0lo ( 1497653 )
          I know. Not on the average (20+mils/7mils sq.km), but were the tech matters is almost already so.

          Fingers crossed for CSIRO, last time they pulled a nice trick with the WiFI patent [itnews.com.au].

    • Unlike 3G networks, which lose download speed with more users, the analog signal would provide a consistent speed no matter how many users there were.

      WTF? Come to think of it, those old acoustic-coupled 300 baud modems never fell back to lower speeds either. Maybe even older tech would be better. Smoke signals would be totally immune to electromagnetic interference. Could they possibly find a less-informed writer?
      Sometimes it seems like net news/info sites are deliberately being clogged with garbage sto

  • The article talks about sending internet access over an analog signal. I think the article writer was a bit off. More likely they're just using the bandwidth formerly used for analog TV, repurposing it to digital wireless broadband. I wish that happened here in the US. The whole comment about the number of users not mattering must be bupkus.

    • Re: (Score:3)

      by catbutt ( 469582 )

      The whole comment about the number of users not mattering must be bupkus.

      There can be any number of users, but they all have to be looking at the same part of the internet.

    • There is no digital.

      The is only analog.

      You can define Vcc as true and 0 as false, but analog they remain.

      There is certainly no digital RF anything.

      • Re: (Score:2, Informative)

        by Anonymous Coward
        There is no such thing as analog. The smallest elements of all that exist are space and emtpy space. Anything can be break down until what left are "is" and "is not". Analog is a aproxymation of the digital reality, our sense can only mesure that much. We see curve where there is jagged surface.

        • Re:Pendantic (Score:4, Insightful)

          by qbast ( 1265706 ) on Tuesday December 07, 2010 @04:11AM (#34471146)
          There is no such thing is digital. When you go to smallest elements (atoms, electrons, ...) you enter realm of quantum physics. There is no clearly defined "is" and "is not" - there are only continuous probabilities.

          • Re:Pendantic (Score:4, Funny)

            by Mr0bvious ( 968303 ) on Tuesday December 07, 2010 @04:38AM (#34471214)
            There is no such thing as continuous probabilities. Once all probabilities are determined you enter the realm of all knowledge. Having all knowledge clearly enables one to know what "is" and what "is not".

          • You have unintentionally exited the realm of physics, and entered the realm of math. The fact is, it is unknown wether matter is composed of waves or particles; requiring it to be both however, is absurd.

            The Copenhagen interpretation of QM is a purely mathematical construct which bridges this fundamental dichotomy, without providing any insight into real physics. It is an abomination that has replaced the search for truth, with the proclamation of an unknowable reality, veiled behind statistics. In essen

      • Re: (Score:2)

        by Ronin441 ( 89631 )

        Dude. In a post about being pedantic, you misspelled "pedantic".

    • The whole comment about the number of users not mattering must be bupkus.

      Not really. We're talking here about a system which directionally targets the signal to the endpoint. It's not like mobile phones where you all share the same bit of bandwidth of the base station. It's a case here of there's an antennae on the base station dedicated to you, another to your neighbour, both with the same bit of bandwidth but don't cross the streams. Well not quite but you get the idea.

      The reason this works is because the technology is aimed at stupidly sparse populations. It wouldn't work

      • It's a case here of there's an antennae on the base station dedicated to you, another to your neighbour, both with the same bit of bandwidth but don't cross the streams. Well not quite but you get the idea.

        Because having a UHF transmitter for each user is going to be amazingly cost-effective.

        • I don't see why it shouldn't be. Despite the "ultra" in the name UHF isn't all that high frequency by modern standards and by using very directional.

          The real question is how directional can you make the antennas before the antennas themselves become insanely expensive. Line of sight is also important.

          • I don't see why it shouldn't be. Despite the "ultra" in the name UHF isn't all that high frequency by modern standards and by using very directional.
            That should have said and by using very directional antennas it should be possible to keep the transmit power low.

          • Economy of scale dictates that 2.4 and 5.8GHz kit is cheaper than UHF. TV aerials aren't particularly high quality, and neither is the coax. You'd have to replace both before they were suitable for data.

            • Re: (Score:2)

              by Khyber ( 864651 )

              "Economy of scale dictates that 2.4 and 5.8GHz kit is cheaper than UHF."

              Yep, and also they have shorter ranges, thus requiring more transmission power than UHF to go further.

              "TV aerials aren't particularly high quality, and neither is the coax. You'd have to replace both before they were suitable for data."

              We do have these things called Radio Modems. Sure you can only get ISDN speed but you didn't have to replace a damned thing, you just plugged the modem into the antenna. I used to use one way back in the

              • Yep, and also they have shorter ranges, thus requiring more transmission power than UHF to go further.

                Or a higher-gain antenna, which is easier to make and more compact at microwave frequencies than at UHF. You've also got the advantage that a high-gain antenna works just as well on receive as it does transmitting, so you can hear weaker signals as well as transmit further.

                We do have these things called Radio Modems

                I know. I design, build and install systems using them. They don't work with TV aerials

                • But since we're talking economies of scale the whole point was using existing infrastructure that is being decommissioned. Suddenly replacing every end user's TV antenna raises the cost again.

                  • Exactly. It's worth considering that Sky Television (UK satellite provider) will quite cheerfully rip out a six month old installation and put a new dish up if a house has a dish left by a previous customer? Why? Because you don't know what state it's in. The cost of just replacing it and doing a new install from scratch worth less than the risk of having a shitty half-broken dish, poor performance and a dissatisfied customer. After however many years on someone's chimney, how do you know what state th

        • Compared to what? Abandoning the end users? Installing new infrastructure? Laying 30km of new cables / fibre to reach a single household?

          Of course it's expensive, but this is a solution to replace satellites to a very tiny proportion of the population likely to be subsidised by the government's national broadband network, not something that carriers will roll out in the city to make a quick buck.

          • Microwave "last-mile" stuff is cheap and effective, and works over the same sort of range we're talking about here. Bear in mind that the distances you can cover in a single hop are limited by the timing in the modem once you've got a good aerial up. Radio waves travel at the speed of light, which is surprisingly slow - about five microseconds to travel a mile. If you try to use conventional wifi cards you need to increase the timeout settings, because it takes so long for a packet to reach the far end a

            • The premise here is that the system is designed to work on fringe signals. If cheap and crappy works then why does it matter?

              I can use an analogy that happened to us at work recently. Our 2-way trunked radio system has worked fine for years. Yet somehow recently an RF engineer was trying to tell me about the benefits of replacing our single 800MHz dipole with 1 dipole for the transmission, and 3 120degree directional arrays for receiving to provide more coverage. The conversation went along the lines of:

      • Precisely. Something like 97% of Australia's population can receive Internet via more conventional means: fibre/cable/dsl in cities and towns, and 3G for 'rural, but not stupidly remote'. This technology is aimed at the remaining 3% who have no means of getting the Internet at all except via satellite. The truly remote. Those whose nearest neighbour is 200 km away and own cattle stations larger than some US states. The kind of people who aren't even connected to the electricity grid but rather generate thei

        • Those whose nearest neighbor is 200 km away and own cattle stations larger than some US states. The kind of people who aren't even connected to the electricity grid but rather generate their own power via generators/solar.

          Shouldn't that "kind of people" be outside minding the livestock on their Rhode Island-sized ranch, keeping an eye on the generator and watching for dingo attacks instead of updating their Facebook page?

          • You do realise that if you own land of that size, it is mostly 'remotely' managed. GPS-tagged livestock. High-res satellite imagery. Detailed weather synoptic charts and forecasts. Decent quality internet service is needed for this. It is not 1950 anymore.

            Also you are implying that such people are working 24/7 and have zero relaxation time. Do you not also think that people that live and work in such places should be able to enjoy the same online entertainment options (IPTV, gaming, etc) as those living in

          • Except that everyone in the world is modernising. Including customers like the supermajor grocery stores, and the transportation companies which provide goods tracking online. Not to mention the ability to file your business activity statements online beats driving 100km to the nearest town to talk to your accountant.

            Not sure if you think that all there is on the internet is facebook and slashdot, or that farmers are some backwards armish people, but the last remote farm I visited had a cow milking syste
  • awesome, because i had such a quality TV signal in the City! it could surely only be BETTER for those people way out whoop-whoop.

    • The city itself was probably a big part of your problem. Done correctly, RF deals much better with wide open spaces than it does with interference-filled urban environments.

  • I wouldn't want anyone to tune into most of the things I watch.

    Unless you're into that/those sort of thing(s).

  • why is it the goal of technology missionaries to deliver the lamosity of facebook to some dude in a shack in the middle of nowhere? Like a neutered dog, i just don't get it... unless it's religion in which case I do get it, but still don't

    • The Australian Federal Government has an obligation to deliver broadband services to people in remote areas. Telecommunication companies have to contribute a Universal Service Obligation pool which is paid to providers who service remote customers.

    • From the governments point of view, it's how public services are going to be delivered in the future.

      In Britain we use a combination of local town council offices and Post Offices to provide information and be a point of contact for requesting and recieving various public services. That requires staff and some sort of office in pretty much every single town and village which is really expensive.

      From the point of view of requesting services and information, a single desktop PC running as a webserver could re

  • Awful article (Score:5, Informative)

    by Animats ( 122034 ) on Tuesday December 07, 2010 @02:49AM (#34470814) Homepage

    I don't have time for a full writeup, but read for some reasonable info. [radioaustralia.net.au] This is intended for areas where the user density is very low, so low that the users are at significantly different angles from the base station, and multiple steered beams can be sent to different users at the same time. They can get about a 6x gain in capacity that way.

    The "reuse of analog" simply means that existing VHF antennas at the user end will work. This is useful, because in remote areas, people already have big towers with fixed antennas pointing in the right direction. The base station antennas change drastically, the modulation scheme changes, the user interface boxes are new. Only the user end antennas remain. But that's the item that's a pain to replace in the field.

    The guy behind this is a serious RF guy, worth listening to. He can probably make this work.

    • You can for sure also increase capacity to 8 fold or more if you can split the antenna field of your central transceiver into separately controllable segments.

      This is possible by using several directional antennas or an antenna system of at least 4 ( or more ) antennas which get a phase shifted signal to cancel out in one direction and to amplify in another one.

      -

      This has nothing to do with analog or digital. Nyquist ist still valid

    • Question:

      Is the frequency truly unused? In the U.S. both the VHF/UHF bands are still being used (by DTV) and the same is true in the EU (by D-radio and DTV). So did Australia truly free these bands? Or were they merely converted from analog to digital and therefore still occupied.

      • Back when the US was on analog TV, nearby stations had to be separated by at least 1 channel - the analog VSB filters were not good enough to prevent interference between signals on neighboring channels.

        With the switch to digital, the waveform's bandwidth is determined by the modulation scheme, so it's easy to meet spectral purity limits and for the receiver to deal with adjacent channel signals. Now they can put transmitters on adjacent channels, effectively doubling the available bandwidth.

        • Waht on earth do US adjacent channels have to do with my originl question about Australia's VHF/UHF bands?

          Oh: And you're wrong. The FCC still requires a one channel gap between DTV channels of the same city, same as was true with analog channels.

          • So I guess WTVR and WRLH [dtv.gov] aren't on physical channels 25 and 26 in the same market?

            My point was that if the same sort of rules exist in Australia, you could move the same number of DTV stations into half the bandwidth that was occupied by their analog counterparts.

      • Re: (Score:1)

        by Mkx ( 614118 )
        In Europe, EU commission passed a decree that we'll also have digital dividend. Frequencies between 790 and 862 MHz will be freed of TV and will be (in some countries already have been) sold for 4G mobile networks. It's a good thing that EC required that ... in some countries (mine included) those frequencies would have remained in (D)TV domain.
    • Technically it will work but economically it much more difficult.

  • Stupidest idea ever (Score:5, Informative)

    by Ezza ( 413609 ) on Tuesday December 07, 2010 @02:50AM (#34470822)

    (Disclaimer, I work for a broadcaster in Australia, so take this with a grain of salt)

    OK for starters the bit about "consistent speed no matter how many users there were" is complete garbage, with ANY radio based system data system.

    Secondly, if you start using the TV spectrum for data in both directions, you start putting a really strong signal OUT your TV antenna, which despite being on a different frequency to the actual TV channels, it is close enough to swamp the (really weak by several orders of magnitude) TV signal on the next band with the (extremely strong in comparison) outgoing signal.

    So you can forget about watching TV while you're using the internet.

    The decision to sell the TV bandwidth rather than just keep it for the public use (eg. super HD TV, or super multichanneling or whatever is in the future) is completely about $$$$ and greed by the Federal Govt so they can sell the bandwidth to the highest bidder.

    Grrr.

    • Umm, Isn't the idea they won't be using that part of the RF spectrum for TV anymore so they can repurpose it for data..? I'd imagine the DTV part of the spectrum is far enough apart so it isn't a problem?
    • Your entire salt shaker was just taken. Either you work at the reception and do something completely unrelated to RF, or you're an RF engineer who decided to comment despite not actually looking at the proposal.

      This is designed in areas where the population is incredibly sparse, we're talking many km between endpoints. The idea is to setup highly directional antennas. These DO provide consistent speeds as there's no sharing of bandwidth. You're not fitting multiple people on the same piece of 3G RF freq
    • Thanks for clearing that up.

    • OK for starters the bit about "consistent speed no matter how many users there were" is complete garbage, with ANY radio based system data system.

      When you have highly directional beams going to the location in a point to point manner, and the same likewise back, you can have as many users as antennas you have to point at things.

      So you can forget about watching TV while you're using the internet.

      Analog tv?? i.e. the tv that is being disabled soon'ish and is going to become free space for which stuff like this would be very useful.

      This will not interfere with their digital tv signals, they are on whole different bands.

      Secondly, if you start using the TV spectrum for data in both directions, you start putting a really strong signal OUT your TV antenna, which despite being on a different frequency to the actual TV channels, it is close enough to swamp the (really weak by several orders of magnitude) TV signal on the next band with the (extremely strong in comparison) outgoing signal.

      so the 64mhz abc analog channel is going to interfere with the 226mhz digital channel hey? what about

      • so the 64mhz abc analog channel is going to interfere with the 226mhz digital channel hey?

        At your TV, yes. Read up on receiver [urgentcomm.com] desense [srgclub.org]. The situation is made even worse by using the same antenna - that means you've got to have filters or a circular mixer that will attenuate the transmitted data signal enough to not desense the TV receiver and at the same time not attenuate the desired TV signal significantly.

    • Re: (Score:2)

      by fabs64 ( 657132 )

      It's an awful article, but I originally saw this a few weeks ago and it was coming from the CSIRO, so I really doubt it's as braindead as the article makes it sound.

      I do know that it was exclusively for very rural areas with a low number of users.

    • Re:Stupidest idea ever (Score:4, Interesting)

      by LodCrappo ( 705968 ) on Tuesday December 07, 2010 @04:05AM (#34471118)

      Geez, I wish the operators of the thousands of amateur radio repeaters on frequencies not so far from TV freqs knew what you know about RF. They would know that the installations they have been using for about 40 years now can't possibly work! How silly of us to have (for decades) successfully used systems which receive a weak signal only a few khz away from a strong signal being broadcast on the same antenna at the same time.

      • Re: (Score:2)

        by kaleth ( 66639 )

        To be fair, those system require somewhat large and expensive cavity filters to work, along with a radio that is designed for such a system.

        A system like this [mountgambier.org] probably isn't practical for internet access in the Outback. (The filter is the set of cans on the lower right).

        • to be even more fair, "cans" are not the only form of duplexer available. modern signal processing can do some amazing things. i hope and strongly suspect the people behind this project are fairly well versed in such things, or they wouldn't have proposed it in the first place.

          • Re: (Score:2)

            by kaleth ( 66639 )

            When you're talking about VHF signals that are only a few kHz apart, it pretty much is the only method available. No amount of DSP can overcome the compression in the (analog) front end you'd get without a diplexer in front of it.

    • I'd assumed it would be like satellite, using a phoneline uplink.

      • Re: (Score:2)

        by afidel ( 530433 )
        no, it calls for symmetrical download and upload. Basically it's wimax on steroids (wimax has a maximum effective rage of 50km).
    • The decision to sell the TV bandwidth rather than just keep it for the public use (eg. super HD TV, or super multichanneling or whatever is in the future) is completely about $$$$ and greed by the Federal Govt so they can sell the bandwidth to the highest bidder.

      I'm sure anyone can come up with many use cases for the spectrum. What do you mean by "public use"? Do you mean reserve it for OTA for TV stations? Those bands were never unregulated anyway. I'm not sure about the detail down south but whoeve

  • Power... (Score:4, Interesting)

    by chill ( 34294 ) on Tuesday December 07, 2010 @03:00AM (#34470858) Journal

    The ability to transmit VHF (TV) into the hinterlands had as much to do with multi-kilowatt signals as it did with frequency. Pump 60 Kw into a 2.4 GHz wifi transmitter with a good directional antenna placed on a high tower and I'll bet the punters in the outback can find a working hotspot -- probably one in China at that power.

    • Re:Power... (Score:5, Insightful)

      by MichaelSmith ( 789609 ) on Tuesday December 07, 2010 @04:21AM (#34471176) Homepage Journal

      The ability to transmit VHF (TV) into the hinterlands had as much to do with multi-kilowatt signals as it did with frequency. Pump 60 Kw into a 2.4 GHz wifi transmitter with a good directional antenna placed on a high tower and I'll bet the punters in the outback can find a working hotspot -- probably one in China at that power.

      You would be talking about over the horizon radar, but it requires megawatts. VHF TV frequencies can refract, diffuse and (to a small extent) skip off the ionosphere. I reckon that 2.4GHz would be easier to pick up on Alpha Centauri than in China.

      • wish i had mod points, i guess a "you are correct, sir" comment is the best i can do.

      • Well, yes and no. (Score:5, Interesting)

        by dtmos ( 447842 ) on Tuesday December 07, 2010 @07:29AM (#34471948)

        VHF TV frequencies can refract, diffuse and (to a small extent) skip off the ionosphere. I reckon that 2.4GHz would be easier to pick up on Alpha Centauri than in China.

        I suspect the GP was engaging in a bit of hyperbole with the "China" reference, but reception of Chinese VHF TV signals in Australia is in fact possible on rare occasions [iprimus.com.au] via the ionosphere [iprimus.com.au]. The propagation modes usually involve simple refraction from the E layer [wikipedia.org] or F layer [wikipedia.org], although occasionally more exotic types of propagation, such as trans-equatorial propagation [wikipedia.org] ("TEP"), occur. However, these all fall into the category of anomalous propagation, occurring for a few hours per month or year and, while interesting phenomena in their own right, aren't suitable on which to base one's daily Internet service.

        It is also true that ionospheric propagation of 2.4 GHz signals is unknown. However...

        There are propagation modes that favor the higher frequencies over the lower ones. Tropospheric propagation [wikipedia.org], for example, is much more effective at 2.4 GHz than it is at VHF, and can occur at all parts of the sunspot cycle, since it depends on weather conditions instead of the ionosphere. For example, Table 2.1 in this article [df5ai.net] shows propagation from California to Hawaii on 2304, 3456, and even 5760 MHz via a well-known tropospheric duct. (See also this discussion [df5ai.net] on the relevance to trans-Australia propagation.) Paths in excess of 6000 km (Western Australia to Reunion Island, off the east coast of Africa) have been reported. But again, this is anomalous propagation, unsuitable for daily Internet service.

        The GP has a point about transmitted power. VHF TV broadcast stations have effective radiated powers ("ERPs", defined as their transmitted powers multiplied by their antenna gains) measured in the hundreds of thousands to millions of watts, as well as high antenna sites (on towers), so it's a bit unfair to compare VHF TV reception ranges to those of 2.4 GHz Wi-Fi systems.

        The main advantage of the proposed system is that the users, in remote sheep stations, won't have to replace their existing VHF TV antennas, which would otherwise be a significant financial investment (and that the system would be point-to-point, rather than point-to-multipoint, which enables frequency reuse without loss of bandwidth). Were this not the case, it would be clear to most RF system designers that a microwave system would be superior to the VHF system. Not only is more bandwidth typically available (remember, there are no competing services in the outback), but a 2.4-GHz antenna the same physical size (strictly speaking, having the same effective area) as the VHF TV antenna would have substantially more gain: The gain of a parabolic dish goes up as the square of the operating frequency [wikipedia.org]. Operating an antenna at 2.4 GHz instead of, say, 60 MHz (in the VHF TV band) would result in a gain increase of 1600, or 32 dB. If it had 18 dB of gain at VHF (a pretty decent TV antenna), it would now be 50 dB at 2.4 GHz. (This is why point-to-point microwave systems were used before they were overtaken in the bandwidth race by optical fiber.) This additional 32 dB of gain would greatly increase the range of the 2.4 GHz system over the VHF system, and would be available all the time -- making for a suitable Internet connection. In fact,

        • I know some people who worked on JORN [wikipedia.org] who could tell me a lot about exotic ways to propagate radio signals but they would probably have to kill me afterwards.

        • Re: (Score:2)

          by kaleth ( 66639 )

          This additional 32 dB of gain would greatly increase the range of the 2.4 GHz system over the VHF system, and would be available all the time -- making for a suitable Internet connection.

          Unfortunately, the additional path loss [wikipedia.org] more than makes up for the antenna gain over long distances, so the benefits are much smaller than you might expect. Beyond 25 miles or so, VHF is going to have less loss, even accounting for the antenna gain. That's part of the reason that low frequencies are preferred for broadcasting.

          • The myth that free-space propagation loss is frequency-dependent is probably the most pervasive misunderstanding in wireless. Read the "Physical Explanation" [wikipedia.org] in your own link:

            The FSPL [Free-Space Path Loss] expression above often leads to the erroneous belief that free space attenuates an electromagnetic wave according to its frequency. This is not the case, as there is no physical mechanism that could cause this. [Emphasis added.]

            Think about it: If free-space path loss increased as the square of frequen

            • The problem is, the effective area of an isotropic antenna is inversely proportional to the square of the operating wavelength.

              should be,

              The problem is, the effective area of an isotropic antenna is proportional to the square of the operating wavelength.

              and

              Dipole antennas, like isotropic antennas, have an effective area that is inversely proportional to the square of the operating wavelength.

              should be

              Dipole antennas, like isotropic antennas, have an effective area that is proportional to the square of the operating wavelength.

              Sorry about that.

            • Also,

              Pleasantly, not all antennas have an effective area that is inversely proportional to the square of the operating wavelength.

              should be

              Pleasantly, not all antennas have an effective area that is proportional to the square of the operating wavelength.

              This is why independent review of technical articles is so useful. You can lead a writer to "Preview", but you can't make him think.

    • The problem with that idea is that, yeah, the person in the hinterlands can hear the tower, but the tower most likely can't hear the response back from that person. The Internet depends on two-way communications. I suppose you could do something like the early satellite internet, where it uses a dialup modem for the 'upstream' bandwidth, and uses the RF signal for the highspeed 'download'. That's a very limiting model, but is better than dialup both directions, I suppose.

  • This article is a good example of how little journalists know about the subjects that they write about. How much bullshit are we being fed when we read about fields that we know nothing about ourselves?
  • Just a minor hiccup there: How are you going to get all Aussie rednecks to browse the same internet pages at the same time?

  • Sometimes I'm amazed by Slashdot (Score:4, Insightful)

    by JSBiff ( 87824 ) on Tuesday December 07, 2010 @08:10AM (#34472180) Journal

    I mean, how it is *remotely possible* that an article with only 1 technical fact (TV frequencies can be used for long-distance communication relatively cheaply), and a bunch of complete *bullshit* (High Speed Internet a "basic human right", Internet as an analog signal, no decrease in speed with increase in users), make it through the editorial screening for the "News For Nerds" site, but I *know* that other articles with much greater merit get completely ignored?

    No, I'm not new here, but man, it's like they just don't give a shit about *pretending* to give a shit about doing their job anymore.

  • Analog tv broadcast of internet would require something that doesnt need perfect transmission the first time, and packets can be retransmitted with error checking and checksums.

    I bet companies like blizzard would LOVE to be able transmit the 15.6gb WOW:cata client at 100 mbps. Also microsoft windows service packs and linux ISO's...things that can be pieced together.

  • This csiro news page http://www.csiro.au/news/Broadband-coming-wirelessly-to-the-bush.html [csiro.au] talks about how efficient the tech is. "CSIRO is achieving spectral efficiency of 20 bits per second per Hertz (20 b/s/Hz)" "CSIRO’s spectral efficiency is three times that of the closest comparable technology and the data rate is more than 10 times the industry’s recently declared minimum standard."

  • ...but the Internet is bidirectional. (Score:4, Interesting)

    by JustNiz ( 692889 ) on Tuesday December 07, 2010 @10:16AM (#34473698)

    So how does this allow the subscriber to send data? Does everyone have to have a megawatt transmitter in their home?

    • This article is sparse on details, but obviously the designers are aware of what is required in the user's home. The existing antennas found in those homes are precisely why this system is being designed, and you obviously cannot put megawatts into the average TV antenna.

      I routinely talk to other ham radio operators in town via repeaters that are 20+ miles away, using 5 watts and a hand held radio with an omni directional antenna. With a directional antenna that gave higher gain, my range might double at

    • Re: (Score:2)

      by jwdb ( 526327 )

      Consider your cell phone - the towers may broadcast in the kW range, but your phone won't output more than 2 W. Nonetheless, the tower can hear it fine. It's merely a matter of having a sensitive receiver.

      This is also another reason why an above post about your net surfing neighbor drowning out your TV reception is hogwash.

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