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FCC Approves Digital Radio, Kills Satellite Merger
n8willis writes "...Just saw this AP article on Excite news: the FCC has just approved the first upgrade in broadcast radio technology in decades. It allows "CD quality" digital signals to be simulcast by stations along with their traditional analog feed. The tech comes from some company called iBiquity, and unlike Sirius or XM satellite radio, there will be no charge for listening. Some radio buff want to tell us what they know about this concept?" And wiredog writes "The Federal Communications Commission has voted 4-0 to reject a $26 billion merger between satellite TV providers Echostar Communications and Hughes Electronics.
Ibiquity's IBOC system Sucks. Plain and simple. Am quality sounds like a 56k rated mp3. The side frequencies are hosed for advertising, and FM is no better, the side frequencies, are again hosed, and the sound quality is NOT CD, it's not even 128k!!! It's like 112! Seriously, the fcc is smoking the reefer. They cannot let this happen to radio.
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I believe the FCC Chairman has a tie breaking vote.
There is nothing inherently safe about liberty. That's why so many people died protecting it.
now with digital signals, you can fit more stations on the local spectrum since digital will not "bleed" like analog does. better sound, and in 10 years or so, more choice...I can definatly see the end of satelite radio if local stations can keep up on the content.
True capitalism = lots of similar companies = jobs for everyone who wants one.
I thought I remembered hearing, a few years ago, something about AM radio going digital starting sometime around October 2002. The original plan, as laid out by the in this news brief (and that's DRM as in "Digital Radio Mondiale", not the DRM we all know and hate) from the Digital AM Radio development Consotium, called for digital AM broadcast to start in 2001. Whenever digital AM does start (if it hasn't already), there may well be an AM renaissance, with many AM stations getting back to musical programming. The only other thing I remember right now is that I believe there are going to be multiple digital channels layered in with the analog broadcast, to give a quality of sound never heard before over free broadcast.
whoever modded that offtopic needs to taken out back and whacked up side the head.
that's a good question. the article doesnt seem to answer it either. normally, yes, there are 5 voters for FCC judgements. my guess: one voter did not participate due to affiliation with one of the groups, or was out sick today?
The One Rule Of Chess You'll Ever Need: Don't play someone who carries a kit in their bookbag.
These 2 things aren't even related.
Satellite lets you have all the channels no matter where you are in the coutry, and you have to pay for it.
The new digital FM is just an upgrade to regular FM, so you'll get some better sound and maybe a digital readout of what's playing. You still get to listen to the same crappy programming.
There's no "will they ever learn" here. It's 2 completely different things.
Can it be "CD-quality" at about 96 kbps? We'll see.
A good site for learning more about IBOC is Radio World Online.
Fortran programmer...oh yeah. Array math for life!
i think something like one vote is kept in a sealed envelope, only to be opened in case of a tie. Otherwise, the envelope (and the extra vote) gets destroyed. IIRC eitehr the Chairman or Deputy Chairman makes that extra vote.
I believe Edge 102 in Toronto has been broadcasting a digital signal for some time now.
We do. The Vice President is the president of the senate and casts the tie-breaking vote.
-C
Michael K. Powell
Kathleen Q. Abernathy
Michael J. Copps
Kevin J. Martin
Additional Information
The Sci-Fi channel is being broadcast over the air now? Wow! Our cable company doesn't carry it... which way do I have to point the antenna to receive it and what channel is it on?
I believe they were trying to use cable companies as the reason for merging since satellite customers only make 25% of the pay TV market, but a large amount of DSS customers have no other choice but satellite. Go take a drive in a rural area and you will see a dish mounted on top of every trailer.
The "technology" page on ibiquity's website is already slashdotted, but I seem to recall from something I read last week that the digital channels were going to be transmitted over existing radio frequencies.
Even if I'm wrong about that, I imagine that these digital radio channels will be carrying compressed audio, so that might allow stations to broadcast several content streams simultaneously. It would be cool if NPR could broadcast a high bitrate stream of a live concert at night, while running multiple low bitrate news and talk streams during the daytime. I would think that technology like this would increase programming diversity on the airwaves, once the price of equipment comes down.
http://www.ibiquity.com/navframe.html?03content.ht ml
I have to be careful not to say too much, since as their site is semi-Slashdotted, it's hard to say how much of this is public info and how much is "iBiquity proprietary" (I work at one of iBiquity's equipment partners, and have been working closely with some aspects of their system)
Basically, when the FCC allocated the current FM spectrum, they allowed for a LOT of channel spacing for special features in the analog sidebands and also to take into account inferior receivers/bad transmitters.
Modern transmitters can now output a much cleaner spectrum. Specifically, the FCC allocated a "guard band" around each FM channel, where an ideal FM station shouldn't have emissions but is allowed to "spill over". The guard band power can only be 1/100 of the power of the main band, but thanks to the SNR advantages of digital modulation, a digital signal needs only around 1/100 the power of an FM signal for the same range.
So IBOC can allow an FM signal and a digital signal to coexist on the *same* channel. A cleaned-up FM signal in the main band, and a digital signal in the "guard bands".
An eventual upgrade path is an all-digital signal, replacing the FM portion with a digital signal for greater bandwidth. This is a while off, due to the compatibility issues and also due to technical issues.
retrorocket.o not found, launch anyway?
http://www.ntia.doc.gov/osmhome/osmhome.html
Chart @
http://www.ntia.doc.gov/osmhome/allochrt.html
Useful links @
http://www.ntia.doc.gov/osmhome/sites.html
-wk
No, they don't. It is more efficent than current television.
I think you are a troll.
Perhaps if you should research this technology before you comment on it? This technology uses the existing bandwidth allocated for radio by allowing existing radio stations to additionally broadcast their signal in digital in their current frequency allocation using much less bandwidth and with additional information like traffic conditions. "It was in this environment that the concept of in-band/on-channel (IBOC) digital audio broadcasting was born [see figure]. The idea was to create a terrestrial broadcasting system using a new digital signal that could be transmitted in-band alongside a broadcaster's existing analog signal. In theory, this would be ideal. It would require no extra allocation of spectrum, replicate the coverage of the existing services, and allow broadcasters to remain independent from one another--no need for combining audio programs as with Eureka." From the IEEE Spectrum
Actually, everything I read made it sound like they had to have their revised plan in before the FCC voted, and the companies had just this week asked the FCC to delay the vote while they presented a revised plan, which the FCC did not do. I think this vote effectively kills this merger, and I really see GM selling Hughes/DirecTV off to the highest bidder at this point. Rupert Murdoch fought vigorously to prevent this merger, so I'd be surprised if someone besides Murdoch ends up with DirecTV.
The revised deal that Dish/Hughes was basically an offer to create/improve other satellite competitors since the FCC's major problem was that this merger essentially created a satellite monopoly. The first part of the plan was to lease space on their spectrum to Comcast, who is starting their own satellite service. Comcast has the spectrum to offer satellite service everywhere in the US except for the West Coast, and Dish/DirecTV would've provided them with the necessary spectrum to offer nationwide service as well as the ability to offer more channels. The second part of the plan was to offer other companies the ability to resell and bill for DirecTV/Dish service, similar to what DirecTV currently does with Pegasus in certain parts of the country.
This is currently estimated at $75,000 for a small radio station.
Please see Digital Radio Takes to the Road specfically the section on IBOC (In-band/On-channel). Specifically see this figure which presents how the data is added to the current AM and FM channels.
The main reasons it's taken so long are technical.
IBOC has a lot of technical requirements that strain even modern transmitter technology to its limits. Old-school FM allows a relatively primitive transmitter to operate *extremely* efficiently since FM contains no information in the amplitude of the signal. Hence, a class-C amplifier can be used, which is pretty simple and on the order of 60-80% efficient.
Digital techniques have amplitude information in the signal. Hence, the amplifier has to be linear, which means that good 'ole class C is out of the question. Most linear amplifiers are at best 50% efficient, and that's theoretical. (Cutting edge technology allows 45-50% to be achieved with the linearities required, but it's a LOT harder than building a simple class-C amp.)
Meeting the iBiquity specs means that transmitter manufacturers need to use the latest and most modern technology they can, stuff that's cutting-edge even for people who have been doing linear amplifiers for a long time.
It's not as much of a problem with digital TV - These guys are AM to begin with, hence have been using reasonably linear systems from the beginning.
I'm not sure how digital works in that regard, but I know with AM, you can get extremely impressive range.
AT NIGHT. AM propogation is affected by the ionosphere, which is different depending on time of day; i.e. at night AM signals bounce off of it and can travel thousands of miles. During the day, however, they are ABSORBED and the only way to recieve the signal is by groundwave. For this reason AM stations (usually) decrease their broadcast power SIGNIFICANTLY at night.
To ensure perfect aim, shoot first and call whatever you hit the target
DAB has been available in Canada for some time now, they've been advertising for it now for over 2 years. Take a look at the DAB Canada site, it explains the technology and lists the stations that already broadcast a digital signal. I know you can buy car receivers ready for DAB signals already...
"Senate Democrats are not bringing any of Bush's appointments to a full Senate vote."
Which continues the 6 year Republican tradition of never bringing Clinton nominees to a vote. Of course, they rarely even brought them to a committee vote.
What's good for the goose...
The technology is called IBOC, which stands for In Band On Channel.
The technology works by using the portion of the 200kHz space that is allocated to every FM station, that the station is not using at that exact instant.
The original choice of 200kHz spacing was set up by observing the nature of FM. The carrier was allowed to deviate from its center frequency by up to 75kHz in either direction. This deviation is used to encode the information onto the carrier.
Audio is added to this carrier at a maximum frequency of 15kHz. The transmission of a 15kHz tone on a carrier, AM or FM, will result in sidebands (think "aliasing artifacts") developing on either side of the carrier at 15kHz away from the carrier.
Since the carrier is modulated by changing its frequency, if we modulate this carrier with a 15kHz tone at what is called "full deflection", i.e. we move it a full 75kHz above centre to a full 75kHz below centre, then the whole amount of spectrum required to do this will be 180kHz. This is 90kHz either side of the centre frequency.
Sanity check: The lowest-frequency artifact will be the lower sideband at the point when the carrier is at its maximum negative deflection. This will be the centre frequency, minus the deflection (75kHz) minus the width of the sideband (15kHz). This, in turn will be 90kHz below the centre.
Similarly, the maximum frequency artifact will be the upper sideband at the point when the carrier is at its maximum positive deflection. This will be the centre frequency, plus the deflection (75kHz) plus the width of the sideband (15kHz). This, in turn, will be 90kHz above the centre.
For stereo broadcasting, some additional, ultrasonic information is added to the carrier (this information is done via a transformation that is beyond the scope of this description). This higest frequency of the modulated data becomes 53kHz as a result of this. This, in turn, is not modulated to full deflection, so it still remains within the permitted space.
For digital broadcasting, the digital data will be carried by a non-FM technique, and will be put together in concert with the analog FM signal. This signal will then be modulated in such a manner as it dodges the current location of the carrier. How?
From my previous description, you can see that the carrier and its sidebands will, at any given instant, only occupy a 106kHz chunk of spectrum (carrier + both sidebands) for stereo, or a 30kHz chunk of spectrum for monaural. The remaining 94kHz or 170kHz of allocated space is empty. The digital data is placed there.
Now, I hear you asking, won't this cause interference to the analog signal? Ths short answer is yes. However, as long as the digital signal is maintained at a lower signal strength than the analog one, an FM receiver will ignore the digital signal, due to a feature of FM called the "capture effect," wherein a receiver is "captured" by the strongest signal it hears, provided that signal is a particular strength over any other signals. The ratio of the strongest signal to the next strongest that still results in the strongest signal winning is called the "capture ratio."
Nutshell, therefore, is that this will require no new spectrum, but will inestead make more judicious use of existing spectrum, unlike digital TV.
One last note, about content. XM and Sirius have the potential to deliver something other than the Clear Channels pablum. That doesn't mean they will, nor does it mean that they will continue to do so if they do in the first place. Broadcast FM, however, and its new digital counterpart, have the potential to continue to deliver community-originated content, where community radio stations exist, such as our own local, WRPI.
www.wavefront-av.com
2 good articles over at Wired. One on the approval of the digital standard and another on the merger rejection.
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That's a lot of channels
Now, the reason that you can't have 99 radio stations in a given market is because the FCC has established what are called Basic Trade Areas, or BTAs. Each station on a given frequency is assigned a BTA that is determined by running a longley-rice propagation model based on tower height and the effective isotropic radiated power, EIRP. There are 3 classes of FM stations, and each is allowed a certain tower height and a certain EIRP. Once the propagation model is run, it is overlaid with the US Census Bureau's population density models to determine how many people that FM station will cover. Once that FM station is given its BTA with so many recipients, any new station that applies for a construction permit, REGARDLESS OF THE FREQUENCY OR LOCATION, must PROVE that it will not interfere with that stations BTA, if the propagation model run on that proposed station shows at all that it will be throwing power into the established station's BTA in a manner that will reduce the number of people who can receive the established station. Due to the nasty nature of reactance modulated radio (FM), there is a high potential for intermodulation distortion, third order products, and many other nasty phenomena that will cause interference to desired stations. The capture effect of FM can mitigate this to some degree, and this effect is precisely the reason FM was chosen for its band.
Herein lies a problem with massive digital broadcasting. Sure, if you chose a datarate, say 128kbps, and used digital modulation such a QPSK, 16QAM, or some other amplitude/phase modulated signal, you would use less spectrum, but you have to be MUCH more careful about interference and signal to noise ratio. FM does not require a huge S/N ratio to work, and it only has to be about 3dB above an on-frequency interferer for the capture effect to fix the problem. However, digital modulation methods aren't so immune. In the case of something like 256QAM, the symbols are very close to each other in magnatude and phase, so it doesn't take much noise to corrupt a symbol.
It should also be noted that the FCC has settled on an amplitude modulated method (8VSB) for DTV in the US while Europe uses COFDM, which is a lot more like FM (because it's orthogonal, COFDM has much less intersymbol interference). I'm aware of tests run by a consulting firm in the DC area that showed conclusively that COFDM was the better choice over 8VSB. FM is also used for the audio subcarrier in analog television.
So, the moral of the story is, you can't just have more.... :)
Ibuiquity is on channel FM. A digital carrier is inserted at a level about 20 db below the main carrier. Because of the 'capture effect' of FM modulation, a signal 20 db down will not interfere with the main (analog)FM signal. However there is a caveat: The above is true only when the FM receiver is in full limiting (strong signal). With a weak signal, all bets are off. By the way, Ibquity runs with a (MASSIVE) 96 Kbits/sec, using a modified form of APT-X compression. Try listening to a 96K MP3 file and you'll get the idea of how good (or bad, depending upon your point of view) Digital FM will sound. By the way, Digital AM radio by Ibquity runs with a (HUGE) 32Kbits/second stream. It just don't sound too good....
This is a very timely question. It is answered in this article and this op-ed.
Basically, because Senator Leahy is holding up several judicial nominees, the Republican have fired back and put holds on several Democrat nominees, including Jonathan Adelstein, a staffer for Senate Majority leader Daschle and the current nominee for the 5th FCC spot.
Traditionally, the FCC is filled with 5 commissioners, the majority and minority leader of the House and Senate choosing one each, and the President choosing the Chair.
This is actually a big mess right now and causing some to observe they have not seen this type of rancor EVER in the Senate (and that is saying a lot).
Meanwhile a gripe about the moderation system. I think it is ridiculous I can't mod any posts under this article now that I have chosen to add something to it. I comment on articles I am interested in, and I mod in threads I am interested, but I can't do both...that sucks (and yes, I understand the reasons to do so. But given the choice, I would rather comment than mod, but the best is to be able to do both).
The FCC and DOJ were particularly concerned that the merger of DirectTV and Echostar would effectivle create a monopoly. Charlie Ergan and the rest of the advocates of the merger argued that the merger was necessary in order to effectively compete with cable. The problem is that in many areas of the country (rural areas, and more than you might think) consumers have a choice of either satellite or nothing. So, the merger would have effectively been a 2:1 and created a monoply in many areas of the country. While it's true that competitive efficiencies may have increased in some urban areas (big satellite company v. cable), the FCC's general policy is that creating competive efficiencies in one market isn't worth creating a monoply in other markets.
Here is a list of stations that is CURRENTLY testing this technology. I have no idea what type of receiver you need for this.
WNEW-FM (102.7) in New York; WETA-FM (90.9), WHFS-FM (99.1), WJFK-FM (106.7), WAMU-FM (88.5), and WTOP-AM (1500), in Washington, D.C.; KLLC-FM (97.3), KDFC (102.1) and KABL-AM (960) in San Francisco; WILC-AM (900) and WPOC-FM (93.1) in Baltimore; WNOP-AM (740) in Cincinnati, WPST-FM (97.5), and WBJB-FM (90.5) in Central, N.J.; KWNR-FM (95.5), KNPR-FM (89.5), and KSFN-AM (1140) in Las Vegas; and WGRV-FM (105.1) and WWJ-AM (950) in Detroit; WWMO-FM (98.9), in Orlando.
[RIAA] says its concern is artists. That's true, in just the sense that a cattle rancher is concerned about its cattle.
requires a new device on the listener's end
It only "requires" it if the user wishes to listen to the digital broadcasts. I haven't heard anything that suggests they're going to be doing away with analog radio broadcasts any time in the near future, certainly not within the next 10 or 15 years. That's a lot of time for prices to come down.
> When did "CD quality" become the standard for excellent sound quality. And why?
If you really want to know, CD quality (44.1KHz, 16bit) is the defacto standard because
A) It was the first digital format that consumers adopted, and was clearly superior to analog, and
B) Because 44KHz is the lowest sampling frequency that does not produce audible artifacts from sampling the CD's target 20-20KHz bandwidth (with a 2KHz buffer for noise filter clamping) as the noise introduced by quantization is above the range of (most) human hearing and can be safely filtered.
Now, one can debate bit depths, because it is likely that 16bit vs. 24 bit might be audible to some people, but sampling rate is pretty much a non-starter. You really don't need higher than 44KHz for playback. You won't hear a difference.
During actual (studio) mixing, you want to keep the bitrate and sample rate higher... While I think 'cd quality' is good enough, continuous requantization at the minimum levels CAN produce audible artifacts. So 96KHz/24bit actually has a place at the mixing stage. You don't need it for playback though.
So, CD quality is the standard because anything 'better' requires more storage, with no audible results, and the technology of the CD at the time very handily held 74 minutes of audio at that rate, enough to fit a normal-sized album. There was some science involved with the initial selection of the sampling rate, and the bit depth just came about from the fact that 16 bits is an even byte-depth, and the minimum required so that no one complained about quanitization anomalies.