Could EXB Band Be Your New Home?

Engineers Would Move AMs, LPFMs and Non-Coms

09.10.2008

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DALLAS  A new group — made of up prominent consulting broadcast engineers and a broadcast lawyer — has proposed a dramatic change in spectrum management: They would like the Federal Communications Commission to repurpose TV Channels 5 and 6 for radio’s use after the DTV transition is complete.

(click thumbnail) Bert Goldman

Bert Goldman, vice president of engineering for Dallas-based Independence Media and a member of the group, spoke to Radio World News Editor/Washington Bureau Chief Leslie Stimson about its dramatic proposal.

The background:

TV Channels 5 and 6 are located at 76–88 MHz. According to the FCC, 1,814 DTV allotments would be operational post-transition. Of those, only 24 would be located on Channels 5 or 6.

Others have called for using Channel 6 spectrum to expand radio; but the Broadcast Maximization Committee has laid out a specific, long-term migration plan that, unlike others, also emphasizes the benefits for current AM stations.

The group says most AMs should move to the new band, where they would operate as FMs on channels of 100 kHz width, enjoy more parity with current FM stations in terms of audio fidelity and gain the ability to go all-digital.

AMs could transition to 100 channels and operate in the all-digital mode. In this way, AMs “can solve the current digital problems they are experiencing, especially at night,” the group states.

But while most would move, the existing band could, under their plan, also remain populated with clear-channel stations that would enjoy more elbow room. Under the proposal, filed with the FCC in its diversity proceeding (Docket 07-294), the old AM band would be “re-packed.”

Furthermore, the group proposes that the FCC relocate LPFMs there and also expand the noncommercial service into an adjacent portion of the new FM spectrum. The entire process might take 10 to 20 years.

BMC is proposing:

• The FCC would extend the FM band to include frequencies 76.1 to 87.7 MHz FM Expanded Band (EXB) with a 100 kHz channel spacing, creating 117 new channels.


• The first eight channels (87.0 to 87.7 MHz) would be reserved NCE channels since they are contiguous to the current NCE band. The proposal would add new 100 kHz digital channels adjacent to the noncom band and remove the existing Channel 6 protections that limit FM stations on the existing NCE band to open opportunities on the existing NCE band.


• The next 100 channels (77.0 to 86.9 MHz) would be used to migrate AM stations to the proposed FM new EXB band channels, where they would operate in digital mode. BMC says after a long transition period, either all stations or all stations except clear channels (Class A AMs) would make the move. It would be up to the FCC to decide whether a sunset provision would apply to analog AM. BMC says it’s up to review as to whether the FCC or the stations themselves decide who moves.


• One channel on 76.9 MHz would be set aside for NOAA/DHS use nationwide.


• The last eight channels (76.1 to 76.8 MHz) would be for LPFM use. BMC says existing LPFMs or those that fully meet appropriate protections (including second- and third-adjacent protections) could at the option of the FCC remain under their existing secondary service status. Otherwise, on the EXB they would be protected as a primary service and likely have better coverage.


• The mostly vacated AM band (540 to 1700 kHz) could open up for multiple uses, including improved AM broadcast service or other use.

Also, the group has conducted some initial research into digital transmission technologies, but BMC is not recommending a particular one.

The BMC The members of the Broadcast Maximization Committee are: John J. Mullaney Mark Lipp Paul H. Reynolds Bert Goldman Joseph Davis Clarence Beverage Laura Mizrahi Lee Reynolds Alex Welsh All are broadcast consulting engineers with the exception of Lipp, a communications attorney at Wiley Rein.

RW: What is the Broadcast Maximization Committee and why did it form?
Goldman: We’re a loosely knit group of primarily engineers. ... Our first official meeting was in December 2007. It’s been kind of held together and sponsored by Paul Reynolds of Reynolds Technical, an engineering consulting group in Birmingham. …
This was one of those situations where we felt like everyone’s complaining about the weather but no one’s doing anything about it. You’ve got the LPFMs, which want more space; and the existing broadcasters don’t want more interference. The non-commercial people want more stations. …
Unfortunately, what the FCC insists on continually doing is further relaxing interference standards, which causes interference, not only to broadcasters, but these LPFMs are going to find that their coverage, when they sign on, is going to be dramatically reduced by interference from the full-power broadcasters. … There will be effects on the overall noise on the FM band and further impact on the ability to operate stations digitally.
The other part of it is the continuing problem we keep hearing from the AM stations that the noise is getting worse and worse on the AM band. Coverage is getting worse. Land use issues and environmental issues are getting bigger. It’s getting more expensive to operate and maintain AM stations. …
Our thought was, rather than just complaining about it and having a standoff of existing broadcasters against everybody else, why not take a long-term view of the future and try to come up with a method by which there could be an orderly migration? And, in addition to the existing band, [a method that] could satisfy the obvious needs of all of these existing users, and potential future users, of the broadcast band.

RW: What is the basis for the plan?
Goldman: It’s a recognized fact that due to the inherent noise limitations on the lower VHF frequencies, for TV the digital doesn’t work so well. It would behoove the television stations to vacate those frequencies and get up into the UHF bands where it works better.
… You can go right down from the FM band and go into Channel 6 and then Channel 5. It makes sense to have a contiguous block of broadcast frequencies. We said this is a once-in-a-lifetime opportunity, with the analog [TV] stations essentially vacating Channels 5 and 6.

RW: From reading the filing, it doesn’t look like you’re expecting all AMs to move.
Goldman: We’re not intending this document to be an allocation — a final document. We don’t expect the FCC to say, “Okay, this is what we’re going to do. And we’ll do it exactly like this.” I think this is more of “Let’s begin this dialogue” and use this as a framework to make this transition.
I think there’s obviously going to be a lot, a lot of controversy and discussion before anything is adopted by the FCC. There will probably be other viable plans, or modifications of this plan that will be set forth that will require changes or modifications to what we’ve filed.
Could you move all of the AMs to this band? Absolutely. We’ve proved that you can do that. We’ve got all the allocations listed on the table. Would you necessarily want to? I don’t know. Maybe, maybe not.
One of the things we looked at was migrating everybody and not leaving anyone behind, and trying to, as close as possible, replicate at least the daytime footprints of the clear-channel stations.
But the other option might be, as we also put forward in this, is to take the daytimers and the small stations, 500 watters, and stuff like that that’s really just adding interference to the AM band, take them out and transition them. And then ultimately leave a lot of the larger stations on the AM band but increase their spacing so that instead of being 10 kHz channels, they’re 20 kHz channels. If you have that kind of spacing available to you, then you can do digital day and night.

RW: You’re showing how it would be possible if some stations were left …such as if the clear-channels stayed with extra protection but everybody else moved.
Goldman: Yes. We talked to some of the operators. A lot of them just couldn’t get their arms around the idea of abandoning those big old clear-channel footprints. So the thought was, if you either tried to duplicate as much as possible the footprints on the new band or if you improved their situation on the existing band, that makes everybody as happy as possible.

RW: Were the people you talked to worried about giving up their nighttime clear-channel signal? Would there be skywave at night with this proposal?
Goldman: There wouldn’t be skywave on the new band, but if they were to stay on the existing AM band and increase their separation they’d have better nighttime.
If they moved to the new band, they’d be, for all intents and purposes, giving up their skywave. But a few years ago I did an informal survey, when I was at ABC [he was vice president of engineering for its Radio Division] and there were really only one or two stations then that sold the nighttime skywave. Both stations didn’t particularly care so much one way or the other about their nighttime skywave. But, from a political standpoint, nobody wanted to give it up.
This was an opportunity to come up with a plan that could theoretically go both ways. You could either try to duplicate your daytime footprint on the new band or improve your existing lot on the AM band by getting rid of some of the clutter and interference.
That, of course, would be up to dialogue between the broadcasters and the FCC as to which one or a combination of those ideas, or other ideas, were used to do this.

RW: To be clear, what you’re proposing is that everybody wouldn’t have to move. It may or may not be up to them, whatever the FCC decides. You’re providing a framework.
Goldman: Yes, though I can’t imagine why a daytime-only AM would not want to migrate to the new band. I couldn’t comprehend that … at least after a transition period. We are not locked into any specific requirements. This should be left up to the FCC.

Proposed Allocation Scheme for AMs Reynolds Technical of Birmingham, Ala., developed the frequency allocation scheme for AMs as proposed by the Broadcast Maximization Committee. Here’s the background on that development as explained by Alex Welsh of Reynolds. Gathered information on all licensed AMs from FCC’s database Used distance formula described in 73.208 (c) to calculate distances (formula is only valid out to 475 km) between all licensed AMs Calculated each AM’s average distance to 2 mV/m or 0.5 mV/m contour and assigned it a new class Created the minimum spacings chart from suggestions by DuTreil Lundin and Rackley engineer Charles Cooper and based on Canadian DTV standards Started alphabetically with call letters in Alaska, assigned the first station in the list a fixed channel (#92) and allocated all other stations in the nation with respect to the first station, based on the minimum separations and calculated distances. We then kept the second station’s new channel fixed, along with the first, and repeated the process. This was done until all stations had a fixed channel that met minimum separations.

We have pointed out that, at the discretion of the commission, they could move everyone if they wanted to and sunset the AM band, keep the clear channels there, repack the AM band to make it digital-friendly or any iteration. We simply demonstrated that if it was desired to move everyone and match their existing 2 mV/m contour that it is technically possible under our plan to do so.
This is not, in any way, shape or form intended to be an overnight fix. … I figure it’s going to take at least 10 years before you start getting reasonable penetration, and probably 20 years before you can say “We’re done with the migration.”
I figure we’ve got a few years anyway before we settle all of the differences to the point where we can say, “This is the final allocation scheme, now you can start filing applications to make these moves.”

RW: Would there still be expanded-band AMs in this scheme?
Goldman: I guess that would be up to the FCC and broadcasters if they want to continue that or not. The plan put forward takes the AM expanded-band stations and gives them a similar footprint on the EXB expanded band . It would be up to the FCC as to whether they said that after a transition period that you’d have to give up the AM analog or not.

RW: Overall you’re talking about changing the channel spacing on existing AM?
Goldman: Ultimately, after you get everybody moved over, like the daytimers, once they give up their AM footprint, and once everyone who’s going to make the transition [has moved], the idea would be that you’d have mostly clear-channel stations left. The existing AM band could then be re-packed to provide greater separation to allow analog and digital without interference to each other, day and night.

RW: So some legacy stations that had decided to remain in the old AM band would have their frequencies changed anyway?
Goldman: That would probably be necessary and not a small issue. There are international treaties involved so it would be a long road to see that part of the plan through if that was the desired path. This was just an idea we kicked around, but if the AM band were retained, repacking it would be a good way to solve a lot of problems.

RW: The non-commercial stations also would love to be re-packed. They say they’re too tightly packed at that end of the FM band.
Goldman: One of the things about this beyond the AM stuff is you add all of these channels for the non-commercial folks and because they’re digital you have a considerably different allocation scheme. You don’t have nearly the same protections to worry about. So you can pack a lot more people in because of the digital.

RW: Because each station isn’t protecting adjacents?
Goldman: Right. There are no second- or third-adjacent issues, and even the first-adjacent issues aren’t a big issue particularly. In fact, on one of the systems we looked at, you can put a first-adjacent EXB station on the same tower — in other words two channels right next to each other on the same tower. The allocation process becomes a lot less restrictive. …
One of the other things we talked about was the fact that a digital exciter isn’t the cheapest thing in the world, and digital transmitters aren’t particularly cheap. LPFMs are not going to have a lot of money to spend on the facility. … They’d use the same transmitter. It would be a multiplex thing, kind of like Eureka-147 but on a much smaller scale. You’d have maybe four or five people that would be sharing maybe $50,000 worth of equipment.

RW: And for the non-coms?
Goldman: They would each get their own 100 kHz channels. That’s how’d you differentiate an LPFM and a non-commercial station, although they would also be in different frequency blocks, too.

RW: What about power levels?
Goldman: To clarify, LPFMs would probably be equivalent to Class A FM station coverage but several stations would divide up the channel so, say four or five LPFM stations would simultaneously use the same channel by dividing up the bit stream. Noncoms would not typically have to divide up the channel with others so they could have multiple program streams and the noncoms would also have different power levels similar to the class designations now on FM.
How those designations were doled out would probably be up to the FCC after a lot of public comment. The AM stations that move to the EXB would also have different power levels and classes that closely match their current 2 mV/m daytime contour.

RW: For the non-coms, you’re talking about extending their portion of the reserved band?
Goldman: Yes, but adding digital channels as opposed to analog channels.

RW: Let’s discuss costs. The filing says some stations would be able to use nearby towers, for example.
Goldman: For an AM station that gives up their AM operation, we talked about the ability to sell off the property and move to an existing tower or something like that. There would be cost savings, environmental savings. Say you’ve got a six-tower array, you could theoretically perhaps chop down five towers, leave the sixth one up and operate from that.
But if you have short, say 200 foot, towers, you wouldn’t want to do that. At that point, you’d probably chop down all of your towers, sell your property and move to an existing tower that’s maybe 300 feet high.

RW: What about the other equipment costs to go onto the new portion of the FM band?
Goldman: They’d essentially have to buy the components of an FM station, an antenna, transmission line, transmitter and a digital exciter.
Let’s put it this way, I would much rather build a 1,000 watt digital FM station than a six-tower directional AM any day of the week. These people are spending a fortune on maintaining some of these [AM] arrays. A lot of them can’t afford to maintain them anymore. So they’re letting them go into disrepair. … If they can take all that property, say, 50 acres and sell it and take $150,000 or so from the proceeds to finance and build an FM station, maybe that’s not such a bad idea.

RW: Tell me about the migration plan to move the TV stations off of Channels 5 and 6.
Goldman: I thought it was one of the most exciting parts of the proposal because everybody said, “There are people that have to stay there, what are you going to do about them?,” in particular Philadelphia. But our crack engineers came up with … feasible plans to move those stations off Channels 5 and 6 and up into the UHF band where they’ll operate better. I suspect a lot of those TV stations are going to say, “Yeah, great. I just spent all this money on a new transmitter on Channel 6. I am not going to go out and spend another half million dollars on a transmitter and antenna.”
And I’d say I don’t blame them; so what you may want to say — and I think this may be up to the FCC — would be that people moving to the new band would have a fee that they would have to pay that would be, say a few thousand bucks — a fee that would go to the people on Channels 5 and 6 to help them move.

RW: You told me the group is not proposing a digital standard, but it sounds like you’re thinking about it.
Goldman: We did look at the DRM Plus system, which is going through final trials in Europe now. We hear it’s going well and its standard is 100 kHz spacing. They’re talking about being able to get at least between two and five audio channels in 100 kHz of bandwidth. It was all subject to their final testing and final revision of the standard. Assuming that it plays out the way it seems to be playing out, that would be one possibility.
Ibiquity doesn’t want me to say anything about their interest or disinterest. I have to be careful about what I say. If you look at the NRSC-5 standard I personally think that there might be a way to design a subset of the NRSC-5 standard to be compatible with the 100 kHz [channel spacing].
Ibiquity is owned in large part by major existing broadcasters, and the large broadcasters are going to be very protective about adding new spectrum. They always have been. The fact that it’s 10 or 20 years in the future may temper it a little bit but I suspect that they’re still going to fight it. The fact that Ibiquity is sponsored primarily by large broadcasters — I’m not sure Ibiquity will choose to play in this game if [the plan] gets favored by the FCC.
I don’t see that as a problem though, because interoperable radios are not that big of a deal. Once you have the digital signal processor built into the radio, it’s just a matter of programming it for different standards. You could have a DRM+/Ibiquity/Eureka-147 interoperable radio that’s essentially software-defined that would pick up all the different standards.

RW: Isn’t it expensive to build a radio with all of those chips in it?
Goldman: It’s probably more expensive, at least initially. But there are multi-standard radios in Europe right now.
There are chipsets, in fact I just read about a new multi-standard chip being introduced by NXP and they are saying they expect their chip to actually be cheaper to implement because manufacturers would only need one chip for whatever system or systems being used, thus simplifying the manufacturing process.

RW: The DRM/Eureka radios …
Goldman: Right. It’s just a matter of processing power and memory. … From what I’ve been told it’s just a matter of having enough capacity in the chip to be able to have the software and processing power on board to process the different standards. They don’t have to process them at the same time, but they’ve got to have the capacity to process them individually.

RW: Backing up a little bit, what kind of reaction do you anticipate? Do you think the big groups will like this plan or no?
Goldman: I think there will be mixed feelings. Having been on that side of the aisle before, there will be an incredible pushback based on fear of new competition and loss of potential asset value by basically diluting the field. …
There have been a number of people who have filed, pro and con. There have also been other people who have filed alternate plans, some of which take components of ours and add to them … some of which say that we’re crazy.
I know we’re going to get a lot of opposition from the existing Channel 5 and 6 users that do not necessarily want to stay there but don’t really want to move, either. ABC/Disney in particular, I think, will be very upset with our plan and I believe they’ve filed something.
But I think overall, something has to give. Because you have to look at what is more in the best public interest. If you go all the way back to what the FCC’s supposed to be doing, is the best opportunity going to be keeping a handful of VHF Channels 5 and 6 operating because they just can’t figure out how to move someplace else? Or, is it going to be opening up service to thousands of new and existing AM broadcasters?
It seems to me that if a case can be made for an orderly transition, this solves an incredible number of problems and opens up an incredible number of opportunities to make broadcasting rejuvenated, vibrant and viable, allow more people to have a voice in their community and just so much more exciting on every level.

RW: You’re getting a mixed reaction, in part, because AMs would all of a sudden be powerful?
Goldman: AMs would have similar parity to FMs after the transition but it would take 20 years or so before you had penetration at the same level and don’t forget, existing FM stations would retain their 200 kHz bandwidth so they would still have twice the bandwidth of stations on the EXB.
On the good side, existing broadcasters might benefit from this because this would provide additional incentive to get digital radios into the marketplace, which would, I assume, include HD-R. And it would also reduce the interference for existing stations by clearing the LPFMs out of the FM band. So yes, from that perspective it might help. Then, of course, existing AM broadcasters, I think would generally be for it.
Some of the big AM, historic, large-footprint AM stations might not be as excited about it. But I think the struggling daytime AM operators would probably in favor of doing something like this. So you’re going to have a mixed bag.
And even the LPFMs, I’m finding the response from them is mixed. Some are saying, ‘This is a great long-term solution, but we need a solution right now, today.’ Obviously, this isn’t a solution today.

RW: When you said earlier that AMs would finally have parity with FMs, did you mean in terms of coverage area and signal strength?
Goldman: I’m talking about for the ones who chose to move to the expanded band. The way we allocated the AMs may send a chill down some existing broadcasters. The 50 kW day and night AM would have the same coverage day and night as the 50 kW daytime-only. That’s a huge difference for that daytime-only AM guy.
I did a couple of comparisons, and you’ve got a guy who’s a marginal player, yes he had a great signal during the day but he went away at night. Who now all of a sudden has a huge footprint day and night. That’s going to, ultimately, really help his value. It’s typically the minority and less well-financed operators that have these daytime-only signals that would benefit from that.

RW: Big AM groups might see this plan as a way to clear out “nuisances” from the band. Smaller AMs, many already strapped, would end up incurring more costs just to move to FM, and then might languish on a new undeveloped spectrum. Why would smaller AMs like this plan?
Goldman: Because the smaller AMs would have the same coverage day and night. Ultimately, they would be on a level playing field with FMs. Long term their asset value would improve substantially I would think.
As far as languishing goes, we would hope that this plan would help develop both the existing FM band digital plan and the new EXB band. Manufacturers and consumers have been saying that they’re not interested in digital until there’s significant new content to justify spending money for new receivers, well, this will be a lot of new content.

RW: Do you believe that if most AMs are given an option, rather than ordered to move — and further, if they must pay a fee to help “buy out” TV occupants — that they will move rather than stay?
Goldman: I think it will depend upon the station. The AM operators I’ve talked to who are smaller ones and daytime operators are thrilled at the prospect. The issue may be similar to that faced by digital stations today — the chicken and egg thing. If the receivers are out there, and the AM stations can significantly improve their sound and coverage, I think the EXB plan will be very popular.

Comment on this or any story. Write to radioworld@nbmedia.com with Letter to the Editor in the subject line.
The reply comment period for the diversity proceeding (Docket 07-294) was due to close prior to our publication date. Those wishing to give the FCC input concerning the proposal may submit late filed reply comments at fjallfoss.fcc.gov/prod/ecfs/upload_v2.cgi.