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IBOC Questions Remain Unanswered

Let's conclude our recent look at the next steps for IBOC with consideration of a few unsettled areas: datacasting, transition beyond the Hybrid mode, IBOC surround and content protection.

A Number of Issues Need Closure Before IBOC Can Really Shine

Let’s conclude our recent look at the next steps for IBOC with consideration of a few unsettled areas: datacasting, transition beyond the Hybrid mode, IBOC surround and content protection.

When the NRSC-5 standard for IBOC was delivered to the FCC last May, it did not include much about datacasting for digital radio. The NRSC communicated that it hoped to have an addendum to NRSC-5 soon that would cover data transmission in IBOC. Since then, the NRSC has produced a revised version of the IBOC standard, called NRSC-5-A, which does include datacasting elements. At press time NRSC-5-A was expected to be delivered to FCC sometime in October 2005, following final approval by NRSC.

It is therefore possible that the FCC’s next Report & Order on digital radio will include rules covering IBOC datacasting, which may help to launch that marketplace. It remains to be seen whether there will be much business in this space, however, particularly given the broad competition for wireless data delivery, and the fact that it is not considered core business by most broadcasters.

Promoting uniformity

If IBOC datacasting is to become a robust market, the most credible scenario might involve third parties with direct interest in point-to-multipoint data delivery, who would partner with broadcasters as delivery agents. Nevertheless, the existence of standards and regulations on IBOC datacasting may help seed such a market by providing a stable foundation for it.

Perhaps the thorniest issue here is how to strike a balance between openness and uniformity in this market, and whether the FCC or some other entity will play a role in this. To promote uniformity, Ibiquity Digital has proposed a number of components and features that it would develop and control. Others have commented that this could provide the possibility for dominance of a fledgling market by Ibiquity, and thus potentially allow an unfair level of control vested in a single commercial entity. While this might be inconsequential in the early going, it could be difficult to resolve if the market later became successful.

Without some coordination, however, all data types will remain more or less proprietary, leaving radio datacasting essentially where it is today with FM subcarriers. Although there will likely remain some market for delivery of proprietary data services in the IBOC context, if non-program associated data delivery is ever to become a mass-market enterprise, there will need to be some coordination and standardization of content. The datacasting components added to NRSC-5-A only deal with specification of datacasting transport, not content. While standardized transport is an essential enabling element to stimulation of an IBOC datacasting market, establishment of a uniform content architecture remains an important, open issue.

Beyond hybrid IBOC

One of the most forward-looking elements of the HD Radio system is its ability to transition from Hybrid Mode, in which analog and digital signals share the AM or FM broadcast channel, to All-Digital mode in which the analog service is removed, and only digital services occupy the broadcast channel.

In the case of FM, an intermediate stage called Extended Hybrid also exists, in which a broadcaster can increase the digital payload delivered from the 96 kbps available in Hybrid Mode up to nearly 150 kbps. The additional data, which can be appended in 12, 25 or 50 kbps increments, can be delivered with varying robustness and latency. It is generally assumed to be assigned to additional service(s), rather than to extending the main service for higher-bandwidth delivery.

Extended Hybrid services might affect reception of an FM channel’s existing analog subcarrier (“SCA”) services, so broadcasters may need to make some decisions, but will that unilateral process be the only consideration? If existing services are terminated, will some FCC permission or notification be required? Of course, the same question applies – with much broader impact – to a broadcaster’s move to the All-Digital mode, for either AM or FM.

Surround sound

The subject of moving beyond stereo on digital radio has been well covered on these pages of late, but there are still some standards and regulatory issues to be worked out here, as well. For one, if multiple surround systems coexist, will there be a format identifier transmitted to allow optimal decoding in the receiver? If so, who will manage the registry of such identifiers?

Further, if surround content is only broadcast on a station’s digital signal, with a stereo version remaining on the analog during the Hybrid period, does this run afoul of the FCC’s existing rules that an IBOC service’s main program audio should be the same as its analog service? This is more than just a difference in processing or audio format, since the two services may actually be airing different mixes originating from separate audio recordings.

Content protection

Perhaps most controversial is the issue of content protection for digital radio signals. If and when any content protection is applied to digital radio, it will almost certainly involve some regulatory action. The recent overturning of the FCC’s Broadcast Flag rules for digital television, and the remaining uncertainty on their ultimate fate, render any similar action for digital radio unlikely to happen anytime soon, however. So it is possible that the next digital radio R&O issued by the FCC will resolve all the issues listed here except for content protection, which it will leave to a subsequent ruling.

Of course, most of the driving force behind enacting digital radio content protection comes from the music industry, which is concerned with any further erosion of its business through uncompensated digital distribution of its content. Yet there are other applications for such protection that might provide benefit for broadcasters or consumers instead.

Consider subscription radio via IBOC supplemental program service or datacasting. This would require some form of conditional access, and if there were a standardized system for this in place – or at least a standard framework for use with a variety of proprietary algorithms – the process of launching the terrestrial subscription radio business would be greatly simplified. Similarly, the downloading of premium content (e.g., music files) via IBOC datacasting would require protection by a digital rights management (the “other” DRM) system, and this, too would likely require regulatory intervention to establish.

Finally, don’t forget about what the FCC calls “assisted living” services, such as radio reading services for vision-impaired listeners. Today these services are offered for free to qualified consumers, and the services themselves enjoy free access to copyrighted content, such as the newspapers, magazines and books that they read on the air.

The services can do this legitimately due to special status that exempts them from copyright rules, which would normally preclude them from legally reading this amount of content directly from such publications without license to do so. But the basis for this exemption is the fact that the reading services are inherently limited in their broadcast scope to only those listeners equipped with specialized subcarrier receivers, which are not generally available in retail outlets. As noted above, ideally the IBOC datacasting world can advance beyond such a balkanized subcarrier milieu into a standardized environment where service quality and equipment costs benefit from digital economies of scale. But if these reading services simply become another standard supplemental service available to all listeners at the flick of a switch, they risk losing their copyright exemption. Thus some form of conditional access or other copy protection scheme may be required, even for a free service.

As the HD Radio train lurches from the station, it’s important to observe the activity that’s still taking place back on the platform – and there’s still plenty of it. Watch this space for continuing updates.