My Thoughts about HD Radio

[frankberry]

HD RADIO


Many people wrongly believe that HD Radio is High Definition Radio. Some stations even promote their HD product as 'High Definition' Radio.
HD ... Hybrid Digital ... is an attempt to add digital service to the existing analog service.
In many cases, the addition of the HD sidebands creates interference to the analog channel.
With AM stations, the HD sidebands are clearly audible on the analog service. They also create interference to their first-adjacent neighbors.
How did this happen? Why did the FCC permit this intentional interference?

For some reason (and probably for the first time in the history of broadcasting in the United States) the FCC approved a single company to provide
formats and broadcasting standards for both AM and FM stations.
This company, Ibiquity, collects licensing fees from the transmitting and receiving equipment manufacturers as well as the initial and annual licensing fees from each station which broadcasts in HD.

In the past, the FCC approved a single standard for monochrome television.
In the early 50s, the FCC approved a single standard for color television.
In the early 60s, the FCC approved a single standard for FM stereo.
In the 80s, the FCC first approved a single standard for AM stereo and then backed-down to their famous 'marketplace decision.'
As a result, Leonard Kahn and Motorola battled and AM stereo died.

Why did the FCC permit Ibiquity to gain a stranglehold on HD Radio?
It's my understanding that one or two of the 'big' owners of radio stations in the United States have a significant financial interest in Ibiquity.
Because of the collective size of these companies, they were able to encourage the FCC to approve Ibiquity as the sole provider of formats for HD Radio.


WHAT IS WRONG WITH HD RADIO?

1. The HD sidebands interfere with the traditional analog service.
2. The HD sidebands interfere with the first adjacent channels on both sides of the 'licensed' HD station.
3. HD audio quality is poor. It's a highly compressed 'red-headed step-sister' of the mp3 format.
4. The coverage of HD is far, far inferior to the coverage of the analog signal from the same station.
5. HD Radio is expensive. It costs the broadcast station a lot of money. It costs the consumer a lot of money.

I predict that HD radio will fail. At some point, station owners will realize that HD is simply not compatible with their existing analog service.

The only way that Digital Radio can succeed is for the FCC to develop a new class of radio. Digital-only.
These digital stations would have to operate on a different frequency band ... perhaps on the low-band VHF TV frequencies.
Most importantly ..... There should not be a single company which dictates the digital transmission standard.
That is the job of the FCC and they should do their job.

 

[spunker88]

I believe the iBiquity HD Radio standard does allow for a digital only broadcast mode. I would really like to see them or another station try out this digital only mode. The sidebands could be brought in, since the analog signal would be gone, and thus the power could be increased to that of the former analog signal since the station would actually be on it's assigned frequency. With a good radio this sort of broadcast may prove to be pretty reliable. The only thing is many people use FM in the car and there are times when the signal will go in and out which does a lot more damage to an HD signal than an analog one since the HD has to buffer. In the city buildings, overpasses, etc do this and in rural areas the larger distance to the transmitter does this. This is one of the issues with making DTV mobile.

As far as AM, HD radio should be discontinued entirely. This is too low of a frequency band to provide digital on. Thunderstorms are your biggest issue, and in some parts of the country there can be thunderstorms almost every day during the summer. There are a few youtube videos showing the effects of the lightning discharge on AM HD signals that are being received well within the service area. The HD signal will go in and out with the lightning crackle. Also there is the issue of skywave interference at night from HD sidebands. The point is the AM band just doesn't play well with anything digital. The FM band does a better job with digital and would have a lot more potential if we weren't using IBOC.

VHF low band would be a good place to go but this is going to require larger antennas since its a lower frequency than FM, but since its right near FM the difference isn't that much. I've often wondered why they couldn't come up with a digital TV/radio system where audio channels could be transmitted along with television channels from the same transmitter using TV subchannel space. If this could be done without affecting current DTV standards it wouldn't be that hard to phase in. Basically transmit a sub channel with no video and only audio. This would require a UHF antenna though in many cases, but UHF signals have proven to be more reliable with digital and in cities (cellular 4G uses the old 52-69 channels). This would require the FCC to give up the notion about the band being used only for TV and instead for anything digital that can serve public interest. I think something like this needs to be done to compete with the internet.

 

[Chuck]

I believe the iBiquity HD Radio standard does allow for a digital only broadcast mode. I would really like to see them or another station try out this digital only mode.

While it is possible than an all digital version might work, who is going to be stupid enough to throw away their analog audience in hopes that a few people might purchase a new radio just to hear them?

It simply isn't going to happen.

 

[frankberry]

I don't believe that the FCC would license a digital-only station at their former analog power level.
In the case of most if not all TV stations, their digital channels are operating at substantially less power than their licensed analog power.
As an example, WTVT, Tampa operated with 316,000 watts ERP analog on channel 13.
Their digital channel (12) was originally licensed for 17,000 watts ERP. The FCC permitted a power increase to 72,300 watts ERP due to coverage problems.
Still, that's quite a bit less than the former power of 316,000 watts ERP.

If a digital-only radio mode is eventually authorized, I would hope that the FCC would limit the station to a single stereo datastream to preserve the quality of the audio.

AM IBOC needs to go away. It was a bad idea.

 

[Play Freebird]

I've often wondered why they couldn't come up with a digital TV/radio system where audio channels could be transmitted along with television channels from the same transmitter using TV subchannel space. If this could be done without affecting current DTV standards it wouldn't be that hard to phase in. Basically transmit a sub channel with no video and only audio. This would require a UHF antenna though in many cases, but UHF signals have proven to be more reliable with digital and in cities (cellular 4G uses the old 52-69 channels). This would require the FCC to give up the notion about the band being used only for TV and instead for anything digital that can serve public interest. I think something like this needs to be done to compete with the internet.

KYES-DT in Anchorage has been doing something like this for years. At one time, the station offered a high quality stereo music service on 22.2 using the Dolby codec (which is already a part of the US DTV standard), but since the digital moved to 5 that subchannel may now be devoted entirely to TV programming. However, I think some audio-only channels are still offered in the KYES "bouquet"; Jeremy Lansman (the owner/engineer) could tell you for sure.

 

[frankberry]

There are a couple of problems with putting an audio stream onto a DTV datastream.
First: You need a DTV receiver to retreive the audio.
Second: How will the TV station benefit?

 

[TheBigA]

The only way that Digital Radio can succeed is for the FCC to develop a new class of radio. Digital-only.

Depends on your definition of "succeed." I have discovered that if you build it, they don't necessarily come.

Just establishing a digital-only radio won't ipso-facto mean success. The consumers are cheap and lazy. Sorry, but that's the truth. Consumers don't want to buy new radios, especially if those radios only receive AM-FM-Digital. Combine them with something else they want, like a phone or a computer, and you might sell a few. But consider the success of satellite radio. They offer digital-only radio, with over 100 channels of commercial free music, and after more than 10 years in business they reach less than 10% of the population. The majority of them got their radios for free with the purchase of a new car.

The BIGGEST problem with HD radio and digital-only radio is that consumers have to buy new radios in order to receive the programmimg, and consumers have demonstrated that they simply don't want to buy new radios. The ones they have do the job sufficiently.

Having said all this, the FCC has said several times, under several different Chairmen, that they see no reason to do to radio what it did to TV, which was REQUIRE a conversion to digital. So without such a requirement, consumers will continue to do the cheap and lazy thing, which is stay with what they have...regardless of the quality.

 

[tomservo]

There are a couple of problems with putting an audio stream onto a DTV datastream.
First: You need a DTV receiver to retreive the audio.
Second: How will the TV station benefit?

I suppose if the TV station is being paid to carry the audio feeds, that's a benefit.

It seems to be more of a convenience thing that anything else. For example, Alabama Public Radio's WUAL in Tuscaloosa runs HD with two subchannels (HD-2: Xponential Radio, HD-3: jazz and BBC_WS in mono) and the subs are carried on the Univeristy-owned WUOA-DT 6 in Birmingham. None of the subchannel programming is available OTA in the market otherwise, as WUAL's analog and HD signal don't reach but half the market.

 

[Casey]

Putting music channels on DTV wouldn't be all that beneficial at this point. You would need a DTV receiver. If you are going to go to the bother of using you TV for music, you might as well just stream internet radio through one of the endless supply of connected devices.

It seems the FCC wants to take away extra spectrum, so I doubt this will ever be very viable.

As far as digital-only radio goes, a good model of how well it would work is the UK. DAB has failed to take up much of the market, despite a purposed shut-down of the FM stations. I believe they also plan to shutdown their remaining LW and AM stations as well, or switch them over to DRM/DRM+. Last I heard the majority of listening remains on FM, the coverage of digital is less, as is the sound quality. Digital radio is simply not meant to be.

 

[tomservo]

The addition of audio channels takes up trivial amounts of bandwidth for the TV station. I reckon it's no more data-intensive than an alt-language track.

The internet costs money each month and is unreliable (well, mine is) but the carriage of radio on TV channels is free to anyone with a DTV tuner (or a cableco carrying the subchannels). I'm thinking of places like bars and restaurants, that could feed TVs off the cable or OTA signal and route the audio for background music or something. A free alternative to satellite radio, even.

DTV reception is a heck of a lot more robust than HD is, so it would be much less likely to dropout, anyway.

 

[Casey]

It may not take up much bandwidth, but if the FCC successfully slashes their spectrum from 6mhz to 3mhz, I have a feeling stations will be less likely to want additional audio streams. And most people have the internet already, far more than use OTA TV. I don't think there is anyway you will get most cable companies to carry audio feeds, as most companies already have some sort of music channels they offer.

You think DTV is more robust? DTV is pretty nice, but robust is not a word I would use to describe it.

 

[frankberry]

I'm not at all sure that we can squeeze TV HD into a 3MHz channel.
It's tough enough to get all of that data into a 6MHz channel.
Even with 6MHz bandwidth, the quality of the HD video is far inferior to the quality of the video on the output of the video switcher at the TV station.

DTV is not robust. Analog TV was far more robust. Under weak signal conditions, you could receive analog TV ... a bit snowy perhaps, but viewable.
Under the same conditions, DTV just goes away.

 

[tomservo]

I mean robust as compared to HD radio. ;D

 

[frankberry]

DTV is a bit more robust than FM IBOC because the digital information is contained within the entire 6MHz channel ...... not just in the attenuated sidebands of the analog carrier. The DTV signal has equal power across the entire 6MHz channel.
Still, the DTV signal can't survive major multipath distortion.

 

[RJ Kanary]

< Still, the DTV signal can't survive major multipath distortion.>

ATSC can't survive atmospheric disturbances, either.Since the thunderstorm season is upon us in Penn's Woods, the Achilles' Heel of ATSC versus lightning becomes apparent again.With NTSC, the audio was still available because it was brought to you by quaint analog FM.With ATSC, you get to see a Scrabble board while the audio is muted, whilst electronics are trying valiantly to locate all the zeroes and ones that composed the warning message you never saw or heard.

RJ

 

[tomservo]

Speaking of multipath, wasn't that one of the things touted as being improved by HD? I spoke to an engineer years ago who was with the early roll out of HD in a southern market and he claimed the HD signal eliminated all the multipath issues his stations suffered from in the hilly parts of the coverage area.

My experience seems to be completely different. I'm down on the coast where the "beach road" is lined with high rise buildings to my south and all the transmitters are to the north. The digital just can't cope there and I suspect it's reflection from the tall buildings. It's not until I drive north of the buildings that the HD stabilizes again.

To be fair, the analog takes a beating, too. For being only 25 miles from a bunch of class C signals, it sounds pretty bad in places. (Tropo doesn't help, either.)

 

[Ai4i]

This company, Ibiquity, collects licensing fees from the transmitting and receiving equipment manufacturers as well as the initial and annual licensing fees from each station which broadcasts in HD.

We feel that ibiquity screwed up in one area:
Once a receiver is sold, the income from it ends.
All consumer receivers should have included a timer, such that every year from the date of original purchase and registration, the digital circiutry would need to be refreshed with a signal transmitted to it by the listener's choice of digital stations. This refresh signal would be handled with any major credit card and would enable the radio to receive any station within the listener's local market. Travelers could have their receivers authorized for reception in multiple areas at a reduced rate.
We are not talking about subscription radio, as the programming would still be totally free.
After about a year or so, we feel that we are freeloading the benefits of this advanced technology.

 

[TheBigA]

All consumer receivers should have included a timer, such that every year from the date of original purchase and registration, the digital circiutry would need to be refreshed with a signal transmitted to it by the listener's choice of digital stations.

How would this encourage sales of the receivers? Isn't THAT the biggest problem?

 

[Ai4i]

We have not worked all the bugs out quite yet!

 

[Savage]

A combat platoon of Orkin Pest-Control servicemen couldn't eliminate all the bugs in HD Radio. Not even with rocket-propelled sprayers and plenty of overtime.