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(Short-, Medium-, Long)wave Radio Meets Digital Stereo
cryptec writes "Today shortwave radio will have some new life pumped into it as the German broadcaster Deutsche Welle will be the first full time shortwave broadcaster of DRM (Digital Radio Mondiale). DRM is a full stereo fully digital broadcast system. The quality of the broadcasts are close to that of FM radio. For samples check out this link." Akai adds this link to an article in the San Francisco Chronicle with some more information, like the involvement of the BBC and Voice of America in this undertaking.
I don't think that's a popular acronym around here.
The goatse guy for president. Win one for the gaper!
Digital radio over SW sounds interesting. I wonder if old Auntie's going to pick this one up? I gather BBC services got cut over North America recently in favour of web broadcasts... maybe digital technology will allow that to be reinstated in the future?
Real Daleks don't climb stairs - they level the building.
Obviously, you will need special gear to receive this - they are using COFDM so your normal shortwave rig is unlikely to give you anything meaningful.
I suppose IF you had a single-sideband rig with a wide enough filter set, and IF you then used your computer, you COULD decode this, but the usual means is going to be a dedicated receiver.
(Hmmm. Have to see if I can get the spec, and see if I can write a decoder for it....)
www.eFax.com are spammers
Hardly the first. Lisp has been doing this for decades.
-- ShadyG
Nerd Rock In Progress
Deutsche Welle will be the first full time shortwave broadcaster of DRM
Broadcasting DRM! How dare they! First, they try to stuff copy-protected CDs down our throats. Then they introduced copy-protected HARDWARE! And now, they're trying to RESTRICT OUR RADIO!
WE MUST BURN TH-eh? Read the article? Bah! I'm fighting Digital Rights Management! No time for that!
RANGE man, range! worldwide FM quality shortwave is gonna be cool.
My potato gun was confiscated by the United Nations. They said I wasn't allowed to have weapons of mash destruction.
Or IRS for International Radio Service?
Or PMS for Portable Media System?
Or any of a thousand other shit-poor choices for acronyms?
Is this truly the only Earth I can live on?
The British Broadcasting Corp., Voice of America and other international broadcasters launched digital short-wave radio service Monday, promising to provide near-FM quality in the place of static-filled signals.
Digital broadcasts don't increase a station's range, but they eliminate static and let broadcasters transmit text, such as news updates and song information, with the audio signal. For now, digital radio receivers are considerably more expensive than analog radios.
The Digital Radio Mondiale consortium launched its digital service at a global radio meeting in Geneva.
"DRM's introduction will forever alter the course of radio broadcasting," said Peter F. Senger, chairman of the consortium, which has more than 80 members.
The initial signals were transmitted from a nearby mountain in France shortly after 8 p.m., when Senger gave the word during a ceremony in conjunction with the World Radiocommunication Conference in Geneva. The conference is held every few years to decide airwave issues such as the sharing of radio and satellite frequencies.
Simultaneously, other short-wave broadcasters started using digital transmitters in different parts of the world. The transmissions received at the reception featured voices in Chinese, French, English, German, Russian and Spanish, followed by static-free music.
For the foreseeable future, broadcasters will use both traditional analog systems alongside the digital transmissions so people with traditional radios will still be able to tune in. At first, broadcasts will be aimed at Europe, North America, the Middle East, Australia and New Zealand.
Digital radio signals are duplicated enough so that even if some are lost from interference, the receiver is able to put the transmission back together so it can be heard correctly. And Senger said the system uses much less electricity than analog, which will save broadcasters considerably on their biggest cost item.
Although the Federal Communications Commission has approved a different digital standard for U.S. domestic broadcasters, Senger said the new system is meant to be universal and could eventually be used in the United States.
Other broadcasters in Europe, Asia and Canada have been using digital transmissions for several years. That system, known as Eureka 147 or DAB, uses a different set of frequencies than traditional AM, FM or short-wave bands.
My potato gun was confiscated by the United Nations. They said I wasn't allowed to have weapons of mash destruction.
Say what you want to about the utility of digital music over short-wave, I think it's a fascinating development. It's just another big application of Peer to Peer technology, one completely bypasses the internet. It's not just music that can be broadcasted this way - files can be sent and they could contain anything - newspapers, video, software, worms - and they could come from anyone with enough power to broadcast them. If the use of such technology becomes widespread enough - look for this becoming just another way to suck data into your computer, no matter how isolated you happen to be.
The flag just makes more sense than the constitution. - Judas Gutenberg
I'm suddenly starting to wonder just how much modern digital techniques bring to the party. For example, remember the technique of bounding signals off of meteor trails? I believe they recorded audio at normal speed, then waited for a meteor trail and squirted it out at many times normal speed... that sort of thing would be trivial and cheap to do with digital technology.
Maybe a LOT of old, low-fi, unreliable radio broadcast technologies can have useful new digital life. It could be very handy as a backup for satellite-based communications.
"How to Do Nothing," kids activities, back in print!
'Ya know, I used to think short wave radio was cool - until I discovered internet broadcast. Now I can listen to stations around the world, without buying any extra gear.
Maybe in the 3rd world, oh wait, the gear is going to be more expensive than SW radio - maybe not there either. Who is going to buy this to get the mass market price down? Not me.
W9x:Thanks for the make-work project Bill.
Does anyone still listen to shortwave? By the way, there's an interesting history of shortwave I picked up one day at the library and couldn't put down. It's called "On the Short Waves, 1923-1945: Broadcast Listening in the Pioneer Days of Radio", by Jerome S. Berg.
Harold
Wie sind die Borg...
:P
Yeah, how are the Borg?
(Wie = How, Wir = We)
Uttering logically derived and empirically supported truths to the disciples of the orthodox establishment.
"what's the point ? maybe I missed something ?"
Well, here in the UK, there's a point. Already the BBC has squeezed so much into it's limited DAB multiplex, that it can only pump out BBC Radio 7 at 80kbps MONO. It's World Service, which sometimes broadcasts music, has an output of 64Kbps MONO, as does it's Asian Network.
If it shifts these services to (ugh) DRM, then the they can be output in stereo, probably at better rates. The remaining services can go up in quality (BBC 6 Music, currently at 128Kbps on DAB, could go up to 160, etc.)
More bandwidth, at better quality. I would guess that that's the point.
Corporation, n. An ingenious device for obtaining individual profit without individual responsibility. - Ambrose Bierce
There are in the US people who actually live so far out in the middle of nowhere that shortwave is the only option for radio unless they want to put up a huge antenna.
Its also a fairly widespread hobby. Starting cost can be as low as $10 for a garage sale world band radio up to several thousand for the latest in equipment.
Its pretty fun being able to hear programs from austalia, india, or wherever someone can muster a few kilowatts to bounce a signal off the ionosphere.
At first glance it looks like the big win would be using the error correction protocols to get through noise and cope with hostile ionospheric conditions.
"The RF bandwidth can be chosen between 4.5,5, 9, 10, 18 and 20 kHz", according to an article at drm.org. Ham voice transmissions already fit inside 3KHz.
There's also a bucket of features which are great for broadcast, like redirect pointers to better frequencies, which are irrelevant bloat in the ham world.
A receiver with a wideband IF output (ie just about any ham receiver), a PC, and a soundcard. That ain't so special; some of you need to free your minds, much less free your radios.
here's a website I found in the UK that gives a very detailed explanation.
Wrap your brain around this.
I tried to digest all of it...
Now my head hurts.
Even if a man chops off your hand with a sword, you still have two nice, sharp bones to stick in his eyes.
It's already been used to decode HDTV signals.
Slashdot also covered this technology a couple years ago.
In an area where 802. gear is pretty much useless because of line of sight issues, this might be just the ticket. There is more bandwidth in an HF carrier than in a phone line, and using low cost DSP tx/rx front ends it would even be possible to utilize two or three channels at once.
Hmmmm.... I think I need to go visit the neighbor.
>> Does anyone still listen to shortwave?
Yes.
SW is the only communication you can get in certain poor rural zones, because:
- telephone lines are too expensive to install;
- same for optic fiber & microwave links;
- FM&AM&TV are't close enough;
- satellite receiving equipment too expensive;
- internet requires one of the above;
- etc.
People really use SW, because they need general news, government announcements and entertainment.
Of course, this idea will only work if someone can come up with an inexpensive enough apparatus.
Now that I come to think of it, this is like Vorbis streaming thru internet, over amateur radio.
Hey, Cringely, do you want cheap internet access? (ok, your project was way cooler, but then, not that cheap...)
One could use a range of frequencies to get more bandwidth (duh). Is this spread-spectrum?
Yeah, they should just reaname the whole country, since the name looks offensive in english.
:)
Just like you can't use the word "niggardly" anymore because it looks like it should be offensive.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
You miss the big picture. Bandwith that onec was negelected due to poor quality can now be used to send reasonable quality sound around the world. There is NO radio technology currently used who's transmision has not been well understood since Maxwell. The change is in frequency hopping and digital encoding. It is doing neat stuff and provign over and over that there is no scarcity of available broadcast specturm. Whey you grok this, you might condlude that satellite is an expensive way to get the message around the world. If you don't grok it, I doubt anyone will miss your input.
DMCA, Hollings, Palladium. What might have sounded like paranoia is now common sense.
In the Harris booth they weren't even running it in stereo. They were using mono voice and it sounded just awful - full of really bad artifacts that made the speaker sound like he was gargling liquid while speaking.
A German fellow came up and was listening to the audio on a second headphone. he commented at how awful it sounded. Turns out that he does DSP for a living - perceptual coding in particular. he had done some work on the coser used and was embarrassed at what he was hearing on the headphone.
By contrast, the DRM samples I hear here sound just great! ...and this with dual (dueling?) bit rate conversions (analog > DRM > MP3 > analog).
FM DAB sounds somewhat better...but then again is's using a 96K bit rate - even Windows Media sounds good at that high a bit rate!
What I'd like to hear is OGG at both the 32k bit rates of AM DAB and the 96k bit rates of FM DAB... My guess is that it would sound great!
It is an amazing coincidence, but I was at the sales pitch for DRM last Friday. Well, apart from things being rehashed here on /. some insider information:
DRM is going to be certified by ITU (International Telecomms Union), basicaly the body that gives the certs for these kind of things.
Most of the digital radio concepts failed because they were able to produce a small run of say 10,000 receivers that would cost an arm&leg when they hit the streets. Well, it seems that DRM will not share this fate, since China, having poor radio coverage in rural areas (FM not viable, shitty AM/SW reception) has chosen DRM as their new standard. Starting run will be ~14mil receivers, so from start they will be able to produce them dirt cheap. Basically the deal is that the West will supply the transmitters, and China will flood the market with cheap receivers.
Otherwise the test rig shown at the pitch sounded really good.
"Dude.... how much is a cellphone now? Aren't they giving them away in blister packs at the grocers?"
:)
In third world countries?!?!? The last time I was in one of those places they wern't giving anything away. Hell you couldn't even get a decent selection of sanitary food in some of those places.
It's true that cell phones cost far less than they used to due to the scale of mass production. Still most retail for $150 US on up. The ones being "given away" are usually refurbs as those have no other market value and it's a cheap way for the carrier to get you to spend an airtime dollar if you're too cheap to sign a contract and buy a phone.
The difference as I see it is that this radio market is going to be a tiny fraction of what the cellular communications market is. So I doubt there will be the kind of numbers you need to bring receiver price down that far that fast.
Maybe the MW market will help drive the price down somewhat and make it afordable for the SWL market. But MW is a hurting market too. If you're in the US you might remember how the MW broadcasters tried like hell to save their market share with the miracle of AM stereo. Or maybe you don't remember that...which would make my point. A lot of people just don't bother with that band because they can get all the programming they want on the VHF FM band without propagation flutter and fade.
Seems to me that the MW and SW listeners are a different breed with different requirements. They're not after high quality signal, they're just happy to have signal. They're not after full digital stereo news, they're just happy to hear the news at all.
Besides, Rush Limbaugh gets his point across in analog mono just the same as he would in digital stereo.
. Quit playing Monopoly with Bill. Switch to one of many non-Microsoft products today.