Slashdot Mirror
Australian Researchers Push Near-Broadband IP Over VHF
Curmudgeon Rick writes "A research group at the Australian National University is getting symmetrical 250K bps at 20km, using "empty" 7MHz-wide broadcast TV allocations in the 45MHz band. Story here, project homepage here. Aim is to put some bandwidth out beyond the reach of the wires, where users are few and far between."
So now even my TV can get b roadband!
Speaking to CommsWorld, researcher Dr Gerard Borg said the ANU has now proved BushLAN's ability to support symmetrical data rates of around 250K bps at distances of up to 40km, using a 20W transmitter and favouring off-the-shelf parts.
I wonder how well attended his talks are at converences?
Ok, there goes my karma!
...but doesn't this just mean one lucky bastard in the boonies will be getting good speeds or 50 unlucky bastards getting crap speed?
vampirical
I wonder if this will be marketed in the US for rural areas. I can hear the slogan now...
"VHF... Australian for Broadband."
i allways thought broadband was at least 10mbit, this is 'only' as fast as 4 isdn lines, sure better than dialup but nowhere near broadband..
It'd be nice, but unfortunately my VCR does not support the Australian internet.
;-)
:)
That's coming from an ebayer embittered by NTSC purchases
Isn't "nearbroadband" almost the same concept as being "almost pregnant"?
This could be a nice alternative for those of us who still aren't able to get broadband (No DSL where I am and Rogers Cable never bothered to run cable to the last three houses. Guess where I am! GRR), without all the potential problems with broadband over power lines (signal leakage, interfering with ham radio).
Does Telestra know this? Surely they'll want to put a stop to any competitors of theirs.
Sorry, but speaking from purely a capitalist's point of view, the keyword here is few. As cool as the technology is, it'll never take off.
IWARS.
People, in general, disappoint me. Politicians even more so.
Mesh networking would be a better idea than all of this. More bandwidth, more parallelism, less power.
It doesn't sound as if they are really ready to talk about frequency coordination with other users. I hope they don't go about asking for spectrum for anything but experimentation this early in their project.
Bruce
Bruce Perens.
only problem is in the US these frequencies are not for broadcasting TV. 7Mhz is for Amateur radio frequencies. US Radio Frequency Allocations
30% Troll, 50% Underrated, 10% Interesting
Score:5, Troll
ANU... go to bottom of page
Conquering that 'last mile'
Pioneering work by physicists and engineers at ANU to build a cheap, simple and robust wireless communication system may soon see regional Australia getting a workable connection to the Internet. The system is called BushLAN, and it's all about bridging that 'last mile'.
Regional Australia has never had adequate access to the Internet. It's either not available, too expensive or unreliable. A major part of the problem is the 'last mile' of access. This 'last mile' is the connection between the central communications hub in a local town to individual residences and businesses. Unfortunately, the 'last mile' is usually much more than just a mile. In rural areas such as Cowra, for example, the last mile has been measured to be anywhere from three to 100 kilometres from the town centre. In more isolated areas it can be much greater.
The cost of cabling to only a few customers over these distances is prohibitive and current wireless solutions aren't practical. Satellite connections are expensive and usually require a cable connection for a user to send information out (ie they receive downloads from a satellite but send information out via the telephone). There are ground-based wireless connections commercially available but these operate in microwave frequencies using directional antennas that require a clear line of sight to function. Given Australia's sparse population and frequently hilly terrain this would require a large number of repeater stations.
Dr Gerard Borg is a plasma physicist at the Research School of Physical Sciences and Engineering. His work with radio transmission has convinced him that the last mile could be effectively bridged using the low-VHF radio spectrum. This part of the radio spectrum has much longer wavelengths than the microwave frequencies used by other wireless systems and this allows signals to be transmitted further without the need for expensive repeaters or satellites. What's more, it doesn't depend on line of sight as the signal has the ability to go around mountains and other large obstacles in the landscape. At the moment the low VHF radio spectrum is used to transmit TV signals but with the decommissioning of some analogue TV bands in 2008 (digital TV uses higher frequency radio) there's an opportunity to switch this unused spectrum over to data connections for regional Australia.
BushLAN (Bush - Local Area Network), as the system is called, has the potential to provide remote users in regional Australia with a permanent, high-quality Internet connection (at more than 100 kb/sec) at an affordable price. However, to get BushLAN up and running, many technical and marketing aspects of this multi-faceted system have to be developed first. To achieve his goal, Dr Borg has enlisted the assistance of a wide range of students from the Faculty of Engineering and Information Technology who have taken on the various jobs associated with the system as part of their Honours, Masters or Doctoral projects.
"The practical nature of BushLAN and its relevance to regional Australia really attracts the students," says Dr Borg. "Once they're involved, they become highly motivated about what we're trying to achieve. Quite often they finish the formal part of their work for their thesis, but then they stay on working on the project through the Christmas vacation."
The next step for BushLAN is to set up local trials to test transmissions, and then work with interested Internet service providers to see how BushLAN can be integrated into existing information systems. The hope is that with BushLAN as part of the system, the 'final mile' will no longer be an unbeatable hurdle.
Science Reporter is brought to you by the National Institute of Bioscience, the National Institute of Engineering and Information Sciences, the National Institute for the Environment, the National Institute of Health and Human Sciences and the National Institute of Physical Sciences. Written by David Salt.
For more information on any of the stories presented here please visit http://ni.anu.edu.au/
Quidquid latine dictum sit altum viditur
In Australia the ACCC defines BroadBand as 200kps and over.
But the term "broadband" has come to mean "fast" in the common language. Thank the media for that.
In the olden days, the highest speed things tended to be broadband, so the meaning just got twisted.
I'd say, considering speeds and waht is noramlly known as broadband in the US... 250kbps qualifies as "near broadband"... people usually think 1mbps is broadband.
As a frequency this low will generally pass through buildings and obstructions much more effectively, it's probably a more likely candidate for inner-city wireless broadband than 802.11 -- on a commercial level.
If some ISP can obtain the correct licenses and find an existing 802.11 chipset with firmware-programmable frequency, they'd be the winners of all time.
I think that the market is UNDER estimated for this than anything. with 20-40k coverage, it is fantastic for rural coverage. And for a country where the majority of the population are active online, this means for rural areas that are spread out over large areas, it is feasible. The expense to cable an area with 10,000 people over a 20km radius is very prohibitive. However, the market for internet of 10,000 people, where network expansion means grabbing a bit more spectrum and setting up another station, is relatively small. I think this is fantastic for our rural areas here in Australia, because FAR too many cannot even support decent dialup. Who makes long distance calls for a 56k connection? Or worse, an unstable one?
Finally, Pr0n on the TV...oh wait...
...when I sat first row at The Donnas show.
No need to find a WIFI hotspot ever! Enjoy high speed net 200kbps, anywhere!!!!!!!!!!
Mod Wisely.
Generally the problem using VHF is that its pretty limited to a few miles unless you are pumping some serious Watts with a gigantic antenna. Also I am pretty sure 45MHz is used for Military VHF communications(I believe the band to 30MHz to 87.975 or some such) but I am not sure about Australia and its Military freqs. I seem to remmember we could send "data" over VHF when I was in but it was hardly used(I just don't think anybody knew how) We did a bunch of teletype stuff that was pretty annoying.
Back to the topic we did hve some mobile but high powered VHF stuff but it was pretty much limited to LOS(line of sight) maybe if your lucky 30 or so miles.
HF would be more impresive because you could bounce that sucker half way accross the world but you crazy antenna configs like sloping V's and such. Then you would have to worry about weather, TOD, and the infamous sunspots.
I am always surprised that satalite internet never really took off in that more people could access the same bird regardless of remote thier location and steup is pretty minimal while the range is outstanding.
But really sucks is when you have to carry them...
It's all Politics
Just imagine how far you could transmit during E layer band openings. Hehehehe
--fatboy
Let's see them push this streaming chrismas carol over their VHF connection :)
Also, the article had this quote which I found interesting: Dr Borg said, any possible license conflicts - with digital radio advocates, and with the remaining users of the appropriate spectrum - would have to be resolved..
I wonder if the resolution will sound like this? All your VHF Bandwidth are belong to US! Resistance is futile. We will use your bandwith for irrelevant Christmas Music Remixes.
Ding Fries are Done! Merry Christmas!
As a transmission engineer, I can tell you this scheme will not work for long. Those frequency bands will soon be reserved for the HDTV spectrum, not to mention ultra wideband interference. J
Look in 1xRTT ie the current 3g offerings by Verizon Wireless and Sprint we use 1.25Mhz of bandwidth and we can push 155kbps.. I even think our EVDO pushes that envelope further.. so I'd think you could do more on 7Mhz of frequency
Nah ... the transceiver substation was run over by a flamin' herd of wild brumbies.
The higher the technology, the sharper that two-edged sword.
Don't Hams do this already? I think it's called tell-type, Not sure.
Sig: BEEeeeP,,Please press pound, so I can get on with my fucking life!
FAQ...etc.
CC.
TaijiQuan (Huang, 5 loosenings)
Either the poster is dumber-than-a-brick or has less than zero understanding of RF engineering.
.
"7Mhz is for Amateur radio frequencies."
So? The slashdot-summary-article very very very very clearly states 7MHz-wide broadcast TV allocations in the 45MHz band
ie Frequency ~ 45MHz
Bandwidth (ie width of the band of frequencies) +/- 3.5
Where oh where does it say "frequency of 7MHz"?
Anyway, this is talking about in Australia. What on earth or any other planet in the known universe does that have to do with FCC allcoation of frequency use in the US of A?
Visit CryptoGnome in his home.
I mean it is a low bandwidth product anyways....you'd think this form of dominance Microsoft would have discovered a long time ago.
Mods, don't waste your points.
This might fly in Australia, but probably not in the US or other large nations. The radio spectrum is a limited resource and as such, a highly competitive one. Amateur radio operators (myself included) are constantly trying to defend our allocated bands here in the US against commercial entities who would like to have it for their own usage. I don't see a system that uses this much bandwidth being practical for US usage.
17W of power to get 40km?
I use/test/setup equipment that goes 50km at 0.5W of power. OK, they're using a non-optimal antenna, but the antennas really aren't that expensive. 17W would kill a bettery quick. No surfing for pron at night anymore.
200kbps is interesting, and as Bruce Perens mentions, they should have been able to get a lot more bandwidth out of the spectrum they are using. None-the-less, they could be making a robustness/raw data rate tradeoff in the modulation scheme. I am probably just blind right now, but I can find any real details on any of the linked to.
One comment above askes about inter-city propgation, and whether this technology would/could be an answer. I think 3G and or 802.15(MAN) are better because they have been designed for intercity communications, and meet or beat the 200kbps mark, which much less power used (this is very important!)
Now we will stand a chance of staying upto date.
Ie transmit data like a tv program between X and and Y will be windows XPs updates between X and Y will be OpenOffice 1.1. Now the special of the week a full linux disto why not the full lot. Now link this into wifi servers ie TV provide the core content the wifi servers mirror it for ones who missed it.
but I thought VHF was already capable of broadcasting and recieving high speed data. Isn't HDTV in the high MB/s data rate? And they broadcast HDTV over regular OTA. Now I know that HDTV is asymmetrical but I remember back in the day there were people broadcasting data back and forth using small transmitters and regular UHF/VHF antennas. They were mainly used for weather data and such but I remember they were capable of massive speeds. It seems to me the structure for such a system has been up for a while, or has Australia just come up with a better way of redirecting the data?
Any aussies here know what would be using channels 0 and 1? Did Australia follow the US when it reallocated the frequencies back in the sixties? I can't even remember what channel 1 got reused for here in the states. I think it was business band radio like for taxicabs and such.
Liberals call everyone Nazis yet they are the closest thing to it.
It sounds as if Ricochet had the hidden transmitter problem. It sounds likely if you could see 7 of them. Did they use any sort of channel reservation protocol?
Bruce
Bruce Perens.
You would get more bandwidth as well.
AU has few people so they have more unused spectrum to play with.
I would think a higher frequency and better enginering would yield better results.
At around 45 Mhz the antennas are still quite large though the signal does tend to travel well over hilly terain in this frequency range and it can propigate via the E layer at the right time of year as well.
Well at least it's not in the middle of the Ham bands for once (being a Ham myself.)
If you don't like what I write don't be a CS and mod it down. Refute it.
Yea I can't spell. So what is your point?
near-broadband on our broadband!
I know you are psychotic, but please make an effort.
Whatever happened to Project Stargate to put Usenet on a satellite channel?
Analogue television channels in Australia are 7MHz wide. The channels of interest are between 45 and 75MHz. BushLAN is not necessarily tied to using a particular block of spectrum, or an entire television channel. BushLAN subdivides available spectrum into 300kHz channels. As always, there is a tradeoff between transmitter power, communications range, and the data rate.
Using two 300kHz channels [for a symmetric full-duplex connection] low power, relatively short range links with a raw data rate of 115.2kbps have already been created.
As to propagation. VHF achieves beyond line of sight range whereas microwave links are limited to LOS. Long distance propagation is largely due to diffraction over hill tops. Atmospheric attenuation is much smaller at VHF (wavelength is roughly 6 metres) than it is at microwave frequencies (wavelength: ~10cm). This allows greater reliability during adverse weather conditions.
It's a stupid idea.
First, there is no big technical deal here. They took some off the shelf radio equipment and made a data connection. Whoppie! Hardly a first. Hogging up 7MHz of bandwidth on an experimental basis can be done by children with Legos.
Second, the "technical achievement" here is dwarfed by the logistical and political one they face by trying to move all other users of this 7MHz of low band within 100s of miles. Not to mention how fragile this link will be, making it unusable for IP telephony, or Xbox Live.
Third, and most important, this is a misappropriation of technology. The only reason they are trying this is because the local carriers are too dam cheap to run a fiber out to the bush. The carrier's simply look at it the short term ROI rather than investing in an infrastructure. That is where the government is supposed to lead the way, and mandate a thing or two.
So instead, precious wireless bandwidth will be wasted on land locked applications.
In 20 years the cost for securing 7MHz of bandwidth, for something that truely requires wireless, will make a $1M investment in fiber look like peanuts, and they will be all scratching their heads wondering why they didn't make the investment earlier.
There were a bunch of people at Stanford who built interesting network things with Ricochet - I think the project was called "Mosquito Net". You could either do point-to-point connections between pairs of them, or do "star mode" by feeding them the magic commands, but I never worked on them myself. They did have longer range than 802.11, so it's sometimes more useful, but of course they're not blazingly fast.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
>In the mean time, I may be investigating satelite internet.
What about ISDN? Pricing may not be bad in your area. 128kbps switched is pretty fast.
Or a router with two plain-jane 56k modems in it. If your ISP supports modem multi-plexing (or whatever its called) you can plug right into the ethernet interface, use DHCP, set-up a firewall, set it to always call back if the ISP hangs you up, etc. That's a 100k connection right there.
3COM has a router like this and it was a lifesaver when our Northpoint DSL went down.
...by Al Gore (inventor of GoreLAN)
This guy is an insidious troll. Check out his previous postings and mod him for what he is!
My God...it's the return of packet radio!
Several companies in 2000 tried to buy small tv stations called lptv's. They opperate on low power; VHF 3kw and UHF 150kw max ERP. They are licensed like other broadcasting stations in the US by the FCC.
Several US companies tried it. ISP's were on board at first but abondoned the plan arround 2001-2002'ish probably decided it was a better idea to build wired networks instead. To build one of these VHF/UHF stations it cost arround $300,000.
Free Instant Site Inclusion
Moderators on crack again!
How is that offtopic? He even quoted the article!
Assumptions about communication technology that apply in the rest of the developed world often simply don't apply down here.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
Where are the rest of you die-hard purists!!!
There are only a couple threads that have mentioned that the term "broadband" is being flagrantly bastardized in this story. Perhaps some new uses will allow for the use of this new near broadband technology to send almost binary data over a quasi wireless transmission path.
I, for one, welcome our new non-technical legislative overlords. All your near basebands are belongs to us?
OK, I'm leaving now... but just imagine.....
I'd count it as broadband.. you are using multiple frequencies of light to transmit signals... over a single medium.
"Multiple signals on the same fiber"
color == wavelength. I realize it's different than what you think of as "broadband" in coaxial or radio sense.. but by most modern definitions of broadband data transmission, it counts.
"Encode information into a band". You use several different colors in the same fiber. Umm... that's encoding information into different bands.
$ units
2084 units, 71 prefixes, 32 nonlinear units
You have: 30 kilometers
You want: light seconds
* 0.00010006923
/ 9993.0819
0.1ms is a heck of a lot better than the average T1.
Don't know the situation in Australia WRT satellite services (number of slots, existing birds, total market size, etc) so this may or may not be relevant. The data capabilities that can be provided by the new Ka-band satellites sounds like an excellent match to this situation. The climate and geography seem ideal -- dry and mostly flat. Of course, the technology is expensive in initial investment, but then it's easy to add individual users. I'm used to thinking in terms of service for the US and/or Europe, where there are a LOT more people than in Australia. Is Australia big enough, population-wise, to make a go of satellite-based service? Could they share a satellite with other countries in the region?
If you search the university website for Bushlan, you find no reference to 45MHz anywhere. The project has been done at 7 MHz RADIO spectrum for doing the research. 7 MHz is near the 40 meter amateur band and indeed is good for long distance communication most of the time. When the TV bands become available in a few years, they will have to adjust frequency, but even 45 MHz which is just under the 6 meter amateur band, and enjoys fairly good communication reliability. You might also consider that in the USA, the TV bands 2-6 have been able to transmit uninterrupted analog signals for over 50 years at distances of over 100 miles (about 160km). Can somebody point me to the 45MHz reference?
... and in regional / rural Australia, the CDMA mobile network has by far the greatest coverage. It's still improving, and a lot of holes are being closed.
Upgrading CDMA to 1xRTT is incremental and compatible. The only issue is pricing of data over the network...
-- All your bass are below two Hz
There's a company in the US that already does this... They have developed receiver (an asic) and encoders to broadcast technology over regular TV broadcast channels without impairing the video picture. It's used in Disney's Moviebeam box, that's currently available in select consumer markets around the US... (Just unrolled). Dunno the bitrates... or such.
http://www.beanleafpress.com
Great. So first I'm +1 Funny, then -1 Troll, and then -1 Overrated. If I'm a 0 Troll, how can I be Overrated? Sometimes moderators don't make a whole lot of sense.
The higher the technology, the sharper that two-edged sword.