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Tuning With Multicasting Ahead

Datacasts Will Change How You Interact With Radio

Datacasts Will Change How You Interact With Radio

The advent of multicasting and other datacasting possibilities doesn’t affect only broadcasters. Receiver manufacturers as well as their component suppliers are grappling with how to design new radios and make it easy for consumers to access the promised new features of HD Radio and the RDS features of analog broadcasting.

These manufacturers want to make sure the consumer’s first experience is a good one.

Some of the questions being bandied about: How will consumers tune to a supplemental station? How will the “seek” or “scan” functions change? How would stations let listeners know there are supplemental channels available, and how would those station designations appear on the faceplate of the radio?

Depending where their design/manufacturing cycles stand, receiver companies are in various stages of discussing or finalizing these and other design considerations as they prepare to go into production for radios that would ship to retailers this summer and fall.

Experts say features such as a “buy” button won’t be in the market for another two years or so, for reasons less to do with design and more with business and regulatory issues.

FCC approval?

For now, manufacturers that are bringing out their first HD Radios are wrestling with the multicasting feature. Manufacturers contacted by Radio World hope the FCC permanently approves the option that a broadcaster may split its signal into multiple streams. Stations doing so already have sought experimental authorization to multicast.

To include that feature in HD Radios, chipmakers planned for features such as multicasting about a year ago.

“We’ve made it a point to let everyone know it (multicasting ability) is a standard part of the TI350 chip,” said John Gardner, product manager for digital radio for Texas Instruments. The previous version, the 300, processed HD Radio only. The new DSP chip processes both analog and digital, he said.

“One processor is less expensive. On a lot of radios coming out there’s no price difference” to add multicasting, he said.

Other than the display and the Select key, which is already embedded in the radio, there’s really nothing to add, Gardner said.

Some HD Radios already in the market can be upgraded to include multicasting with a software change, he said. That’s the case with the Kenwood HDR100.

At first, several experts said, when tuning to a supplemental channel listeners will see an icon or text display and click on it to tune to the SAP.

“We’re trying to keep it as close to how you interact with the radio today,” said John Crisco, product line manager for Polk Audio, which this fall plans to ship the I-Sonic entertainment system, which includes HD Radio and associated multicasting ability, as well as DVD and CD players. It’s also XM-ready.

HD Radio receivers lock onto the analog signal first, while buffering the digital, much as satellite digital radios do (although in satellite radio there is no analog to hear first, so the user waits for a few seconds for tuner acquisition).

Acquisition time for the digital signal was estimated to take between 4 to 7 seconds for HD Radio, depending on manufacturer.

For example, he said, “When you tune to 88.1, if they are HD, it will have an HD logo. It will blink as it starts to lock into digital and then come in solid once the signal is locked in.” This would be true for the main or supplemental channels, he said.

To tune to a SAP, the listener would hit “tune up” or turn the dial to the right. The next channels would be 88.1-1, 88.1-2 and so on.

A signal currently may be split four ways, he said, including the main channel and three supplemental channels.

Format-related issues

Receiver manufacturers also are taking into account how stations might program the extra channels, be they formats related to the main digital channel or unrelated.

Some broadcasters, for example, might tie their channels together, such as a package of new country, classic country and bluegrass. Or the main channel might be supplemented by the multicast content, such as a package of classic rock on the main channel, artist interviews or other related material on the first supplemental channel, and traffic and weather on the second.

A different situation arises when the station splits the channels into unrelated formats, such as classic rock, news/talk and local ethnic programming.

Manufacturers are keeping multicast station designations simple in first-generation production as they wait to see how stations brand their additional channels on the air. Having a jock say “WCBS(FM) HD-1” is quite a mouthful, for example.

Many stations are waiting to promote their digital conversions until more digital receivers are available; in interviews, manufacturers said they expected to ship product to stores from August to October.

“Kenwood chose to make each multicast channel a distinct ‘station,’ so that tuning is intuitive,” said Mike Bergman, vice president of new digital technologies at Kenwood USA. “Dial up the dial, and you hit every main and supplemental channel. Presets on supplemental channels work as they do now.”

With the Kenwood design, the user can set a preset on HD-1, another on HD-2 and flip back and forth. When the user goes to either, there will be a short delay while digital is acquired. In the case of HD-1, the user would hear the analog first, then digital. In the case of HD-2, the user sees the word “LINKING” or another message for the first few seconds, before the tuner acquires the digital audio, Bergman said.

“Going from HD-1 to HD-2, or back, after you first acquire the station’s HD Radio signal, will be very quick,” he said.

Boston Acoustics’ approach is to use a knob for tuning and to display the frequency digitally, with no scan function.

On the Recepter HD unit, when someone tunes to a station, say 88.5, the listener would see an HD indicator while the receiver acquires the analog signal; some 7 seconds later, it indicates that the digital signal has been acquired.

Keeping it simple

The radio lines up the channels in order; if there are multicast channels, “an indicator lines them up in a row, such as, 88.5-1, 88.5-2,” said Stephen Shenefield, senior director of product development, Boston Acoustics.

“As you go up the dial and back, the radio will remember what’s going on, puts it in a linear sequence that you’re accessing with a knob,” in order to keep the process similar to traditional tuning, he said.

Delphi has developed an OEM automotive tuner module for HD Radio on which it plans to begin production in two months. “That tuner module was designed to interface with Ibiquity’s system,” said Dr. Robert Schumacher, business line executive for the Delphi division of Delco Electronics Systems, who added that all new Delphi radios are HD Radio-ready.

Delphi’s vehicle customers are interested in the technology, he said, and once vehicle manufacturers commit to putting HD Radio in vehicles, the company could get product to market quickly. “They’re interested and asking a lot of questions.”

Jeff Marrah, manager of receiver technology for Delphi and co-chair of a National Radio Systems Committee task group on identifying supplemental audio channels, said the group is looking at two approaches.

One is a so-called “layered” approach, in which “you’re on a specific frequency and there’s a layer of streams behind that frequency, such as HD-1, HD-2. That’s what’s out there today for products that have supplemental audio.”

Another proposal is to take the supplemental streams and lump them into a separate band. The group is looking at the pros and cons of each approach and will report its findings to the DAB Subcommittee, Marrah said.

And what of other potential datacasting services for HD Radio?

Some stations could use a supplemental channel as a subscription service for on-demand, real-time traffic and weather. HD Radio can provide a bigger “pipe” into the car than RDS, said Schumacher, as stations re-purpose the traffic information they have and marry it with a navigation system and HD Radio receiver.

The so-called “buy” button, often touted as a possibility among IBOC proponents, is likely a year or two away, experts agree.

While the separate elements exist to make the technology feasible, such as a cell, satellite or Internet-linked back channel that communicates information from the station back to the customer, a business models needs to be in place to support the additional necessary infrastructure.

Digital rights management also would come into play with this model, experts said, so that buyers would not be able to redistribute digital music they purchased.