FM Xtra digital broadcasting

[RadioFixerCLE]

Has anyone played with this? Or even seen radios for sale that use this system? According to Wikipedia, there's a handful of stations here in the USA that use the system -- NPR seemed like it was a big proponent at one time.

What it does is it uses an FM station's subcarriers to broadcast multiple digital streams. Depending on how many digital subcarriers you have, you'd have to reduce your analog signal to mono in order to free up space.

Tech overview here: http://www.dreinc.com/products/technical.html

And their vapor-ware radios:

http://www.dreinc.com/products/radio.html

I call it vaporware because I've yet to see one of these things hit the market. ???

 

[Tube Shortwave]

FMXtra is definately the way to go. Best part- No fees to broadcasters! Ibiquity does NOT want FMX to take off, they would go out of business. It makes the most sense from all standpoints, except for Ibiquity and their partner, Clear Channel.

I love that Tovoli looking radio receiver. Sweet!

Hey, if enough FMX receivers were out there, it would be interesting to see how many stations went mono for full streamwidth capability. I remember when KSTN FM was mono out here. It was funny to see an FM in the 90's without a stereo light on my radio.

 

[FFoti1]

FM Xtra also affords us some other advantages. Many of you are aware that we have been working on a method to transmit discrete 5.1 Surround, using the HD Radio system. Well, we have researched, and figured out a way to transmit discrete 5.1 using the stereo channels of the conventional signal, and embed the surround data within the FM Xtra stream.

This would enable broadcasters to transmit 5.1 Surround *without* the need of HD Radio...AT ALL! Additionally, this is 100% backward compatible to FM-Stereo, and mono as well.

We plan to announce a few on-air test locations in early 2008.

BTW: If you're wondering, we haven't abandoned the HD Radio scheme. Since HD Radio doesn't appear to be growing as iBiquity thinks it should, we're looking into other ways to bring the 'WOW' factor of Surround to broadcasting.

-Frank Foti

 

[Sgeirk]

While on the subject, with FMextra, you can also simultaneously broadcast using the Ibiquity system, too.

A local station did a demo last spring, and I was thoroughly impressed.

In China, for the olympics, according to what they'd said: a station will turn off their stereo pilot and broadcast 10 separate languages of coverage simultaneously over 1 FM channel/freq, each 'stream' running 10kbps for voice. I heard BBC at 10kbps and it was just fine.

Price tag was around 20k (?)...plug and play, basically...no separate antennas no dummy loads, combiners, or other scary stuff.

Don't listen to me, look into it for yourself. But, do yourself a favor, look into it.

 

[gtomas]

Has anyone played with this? Or even seen radios for sale that use this system? According to Wikipedia, there's a handful of stations here in the USA that use the system -- NPR seemed like it was a big proponent at one time.

I haven't played with it myself, but I've heard only positive comments from those who tried it on their station. You should contact Lyle Henry (the "Radio Doctor") who has installed and demoed the system on quite a few stations across the USA. He will be able to give you all the details.

I quite liked the system from the beginning, because it's compatible with analog FM but without any side effects (intereference), no new transmitters, combiners, etc, it uses MPEG4 standard aacPlus codec which is better than the HD Radio propriety HDC and people report very good sound quality and signal strength and robustness as well. You can also use it as an STL. The only drawback is the small bitrate available when you use stereo FM + RDS, but if you just drop RDS you'll get ~ 64kbps which is very, very good with aacPlus and if you go mono this increases to the whooping ~ 156 kbps which you use to split into several channels.

I wish they marketed the system as a digital radio alternative to HD Radio (IBOC) instead of promoting it as just a digital SCA, because in my opinion it has much more potential than that.

And their vapor-ware radios:

http://www.dreinc.com/products/radio.html

I call it vaporware because I've yet to see one of these things hit the market. ???

It's not vaporware, it exists and apparently it's quite good receiver, not only for FMxtra but AM and FM as well. IIRC there was a review on it in Radio Guide or Radio World or somewhere... Here's short video of Lyle presenting the radio:

http://www.pubtech.org/resources/fmxtrademo/fmextra-web.mov


Regards,
Goran Tomas

 

[rrsounds]

Lyle Henry helped arrange an FMExtra demo in our booth at last April's NAB (and I hope we can do it again April 2008). We had simultaneous separate 25 kbps stereo and 10 kbps mono programs, along with normal analog stereo. I was quite impressed with the quality. The 10kbps stream was especially impressive; tailored to voice only, it had little of the 'swimming/burbling' sound of typical reduced-data audio.

Last I heard, the total, one-time cost to the broadcaster is under $10,000 for the hardware, with no licensing fees.

The receiver is indeed available, if you look for it.

Kind Regards, and Happy Holidays!
David

 

[kyscott]

Has anyone played with this? Or even seen radios for sale that use this system? According to Wikipedia, there's a handful of stations here in the USA that use the system -- NPR seemed like it was a big proponent at one time.

What it does is it uses an FM station's subcarriers to broadcast multiple digital streams. Depending on how many digital subcarriers you have, you'd have to reduce your analog signal to mono in order to free up space.

I have had a chance to talk to Lyle at the NAB Vegas show several times. Very interesting young man and I enjoyed our conversations. Yes, the FMXtra is a much superior system to the current IBOC system we have now. However, interests with deeper pockets are keeping the technology suppressed. I will try to get in touch with Lyle to see if he can come over and answer any questions you may have.

 

[Fieldtech1]

I was told with this system, one mono FM station can run up to 6 different decent quality stereo subchannels or 8 if you tandem it with IBOC subchannels. Talk about instant 9 station cluster on one FM...

Only $10000 and 6 subchannels, No wonder the IBOC guys want this technology to fade away

 

[BobOnTheJob]

I understand that FCC rules limit it's injection level to that of a standard SCA. I want to say that's 20%. For this system to reach it's full potential, that limit would need to be rescinded. At that point, a station could decide what % of their signal went to analog & which to FMXtra. Initially, 20% and a normal stereo signal might be desirable. 5 years down the road, a broadcaster with low analog ratings may choose perhaps 50% analog (mono) & 50% FMXtra. If this were to take off, the playing field would be leveled considerably. A class A FMXtra with 100% injection would be a powerhouse compared to a class B with 20% injection. It's a fascinating concept...one I would love to see gain traction. Meanwhile, I continue to succesfully sell 100% of my clients on NOT embracing IBOC...hopefully other contract engineers who feel as I do will be equally successful...

 

[Chuck]

he beauty of FMExtra is it’s such a simple idea that I'm surprised that you or I didn't think of it. Simple and easy to understand is good.

 

[Play Freebird]

I understand that FCC rules limit it's injection level to that of a standard SCA. I want to say that's 20%. For this system to reach it's full potential, that limit would need to be rescinded.

Lyle stopped by last summer and gave a couple of FMeXtra demos in this area. At the recommended subcarrier injection level (with main channel set to 100% modulation on "peaks of frequent recurrence"), the bargraph mod meter on front of the exciter consistently peaked between 140 and 150 percent, however Lyle assured me that this was OK from an occupied bandwidth standpoint. The average injection probably complies with the 20% SCA injection limit, but momentary peaks could go much higher, and therein lies the rub.

If FMeXtra continues to make inroads, we might see the following scenario:

1) iBiquity or others with a stake in IBOC begin to feel threatened and order their lawyers to contact the FCC.

2) The FCC Media Bureau lawyers read the "letter of the law" and decide that the instantaneous total deviation of the analog FM signal cannot exceed the 110% limit spelled out in the rules for stations with 20% subcarrier injection.

3) The FCC Enforcement Bureau is directed to crack down on FM overmodulation, after several years of lax oversight.

4) EB monitoring vehicles are dispatched to transmitter sites, peak deviation measurements are made, and "zero tolerance" violation notices are sent out.

5) This turns into a major dispute over nothing. (Those of you who worked in television back in the '70s may recall the fuss over blanking interval violations after U-Matic VCRs started making their way into stations. This would be a similar situation.)

By the way, when Lyle was here for the demo, I sampled the transmitter output with a good-quality RF spectrum analyzer and agreed that the emissions remained well within the analog mask. FMeXtra at 40% peak injection certainly causes less spillover into adjacent channels than HD sidebands, but is this too much for the FCC to comprehend? Their policy decisions never fail to disappoint me.

 

[audiophile.]

What does the modulation read on a Mod Minder?

 

[semoochie]

I was under the impression that any multipath interference suffered by the main channel would still come through using the FMeXtra system. Is that true? If so, I think it should only be used as a complement to the IBOC system.

 

[Sgeirk]

multipath doesn't affect IBOC?

 

[Lyle Henry]

Hi gang. I heard that my name was being taken in vain so signed up to join the fun.

Yes, I've done many FMeXtra demos and installs around the country. After 40+ years doing analog SCAs, this system really caught my attention. Now I do a little consulting to Digital Radio Express up in Milpitas, CA where they've developed FMeXtra, although I don't sell it or represent DRE.

Most recent install is at a studio in Quartz Hill, CA. They're now using an FMeXtra encoder and addng the feeds to two other stations into the composite STL to the KGBB transmitter which is up near Mojave. Then stations near Ridgecrest pick the digital SCA off KGBB with DRE's Aruba radios and put it on the air. One station is stereo and we've set its feed for 32 kb/s; the other is mono at 16 kb/s. Using aac+Ver.2. AMR-WB+ can also be selected.

The encoder is a rack-mount XP Pro compter with a Lynx audio card and a digital SCA generator card added. Special endoding software, too.

Regarding injection, 20% RMS is maximum for stereo stations; 30% for mono. High speed digital signals have a peak to RMS ratio of 2-3 to 1, but the peaks are narrow and mostly ignored by peak weighted modulation monitors like the Belar Wizard or MSI ModMinder.

I have a couple of papers and other stuff I've written up on what FMeXtra is and can do as well as how to set injection if anyone wants them.

 

[bilco]

Lyle has chimed in with the facts and he's the Guru of FMX. Two years ago we tried it from a 100 watt translator I have in Las Vegas, and it sounded pretty good while we drove around the LV area, but the translator did not have enought oomph to penetrate the NAB Convention center building. Later that year and last year he had it on a full power FM and it sounded fine. It is a great system to get additional channels that are fully compatible with the existing FM. THe receivers are out there. Even the little box Lyle had sittingon my dash as we drove around sounded like it would keep most people very happy. THe addition to the translator of the FMX stuff took all of 15 minutes minus travel time to the transmitter.
Bill

Bill C. the Chief E.

 

[semoochie]

Sqeirk, when HD kicks in, there isn't any interference at all! I'm saying the HD system could default to FMeXtra until the station gets out of the multiplex coverage area and then default to good clean mono. It's a chance to rid ourselves of the multiplex system once and for all!