Don't touch that dial. Makers of chips and receivers for digital radio are gearing up for what could be a mammoth shift in AM/FM broadcasting technology.

At least 18 manufacturers of radio receivers, including such giants as Bose, Delphi Delco, Kenwood, Mitsubishi, Panasonic, Sanyo, Siemens and Visteon, are planning to roll out digital receivers based on iBiquity Digital Corp.'s HD Radio technology. Kenwood Corp. launched its first such product, an aftermarket "black box" that sits on a vehicle's trunk and connects to the existing radio, 11 days ago.

Several other manufacturers, including Visteon and Delphi Delco, plan to unveil automotive radios for OEMs in the first quarter of 2004.

Industry observers say they ultimately expect the digital radios to gain traction in the broadcasting world. "This is not a question of 'if,' " said Laura Behrens, a senior analyst for GartnerG2 (Stamford, Conn.), referring to the ultimate success of HD Radio. "It's a matter of 'when.' " Behrens added, however, that the market phenomenon could take as long as a decade to fully materialize.

Executives at iBiquity, sole owner of the HD Radio technology, say they expect HD Radio volume to reach the tens of thousands next year, hundreds of thousands in 2005 and millions in 2006. Sometime in the next decade, many experts also believe that the 18 million car radios sold annually in the United States will switch over to HD Radio.

"In five years, we're not going to be talking about 'HD Radio' anymore; we're simply going to be talking about 'radio,' " said Bob Struble, president and chief executive officer of iBiquity (Columbia, Md.). "This is going to become the new standard for radio."

Riding waves

That's not to say, however, that all analog radios are ready to go digital. Even proponents of the technology acknowledge that conventional radios aren't going away any- time soon. Today, there are more than 800 million radios in the United States, with 70 million more being sold each year. Many of those radios bear such low price tags that it would be virtually impossible to carry an additional cost burden of as much as $200 to add HD technology.

"We know for sure that nobody is going to pay an extra $200 for a Walkman or a clock radio," Struble said. "We also know that those 800 million radios in the U.S. aren't all going in the garbage overnight. The changeover is going to be a long, drawn-out process."

Automobiles are likely to represent the technology's earliest adopters. Carmakers reportedly see HD technology as a drawing card for a broad swath of automotive audiophiles. The reason, they say, is that the HD sidebands deliver richer sound, boosting FM radio to CD quality and improving AM radio to FM-like quality.

Receiver manufacturers are achieving it by pairing iBiquity's software with digital signal processing chips from such companies as Texas Instruments Inc. and Philips Semiconductors. Texas Instruments rolled out its DRI250 HD Radio chip in early September, while Philips unveiled its HD chip, the SAF3550, last week.

Many receiver manufacturers say they are developing their next-generation products with HD Radio in mind. By designing the systems around a basic platform that captures conventional AM and FM analog signals, and then making it amenable to the addition of plug-in DSP modules to capture so-called HD sidebands at 10.7-MHz intermediate frequencies, receiver makers can add HD capabilities in a modular fashion.

"We've been architecting our systems so that they will be compatible with HD Radio," said Matt Yarosz, design engineer in the RF Building Block Group at Delphi Delco Electronic Systems (Kokomo, Ind.), which is adding HD capabilities to its Gen7 receiver line. "If an automaker asks us to configure our radio such that it can receive HD signals, we can easily do it."

Still, HD receivers often contain built-in DSP capabilities in their basic platforms, as well as in the plug-in modules. Visteon, for example, uses its own Mach Madre DSP technology in the receiver platform. The company's basic tuner separates analog signals using the Mach Madre DSP and separates digital signals through a plug-in digital baseband processor. On-board circuitry then compares the strength of the two sets of signals and employs a "blending" process to produce the strongest possible output signal.

"We want to make sure if you're in a weak digital domain, for example, it can compare the analog and digital signals and provide the best solution," said Mark Weston, product development manager for Visteon Corp. (Dearborn, Mich.). Weston added that such capabilities are particularly important for vehicles driving through mountainous regions or between tall buildings, where signal strength can be weak.

Chip makers are also lending a hand in development of the modular concept. Philips' SAF3550 chip, for example, works hand in hand with two previously introduced ICs, the SAF7730 IF-CarDSP and the TEF6721 companion tuner. Receivers that employ the original two chips can serve as a foundation and then, through the addition of the plug-in module, can be transformed into an HD product.

Engineers say that HD capabilities can't be achieved through the use of a conventional microcontroller. DSPs are needed, they say, to run the number-crunching algorithms employed in HD signal processing. "A microprocessor could do some of the multiplexing, but it can't give you the control that's needed to analyze signals within the audio spectrum," Visteon's Weston said.

Issues resolved

HD Radio's prospects haven't always been so rosy. Earlier this year, product introduction schedules had to be pushed back when problems were discovered in the HD Radio codec. Glitches were especially noticeable in the AM band, where so-called artifacts muddied the output signal, causing speech to sound slurred.

Since that time, however, engineers say they have replaced the codec and are moving ahead with plans to put HD Radios into OEM products. "The new codec has basically eliminated the artifact concern," Weston said.

At a forum in Washington recently, broadcasters and Federal Communications Commission representatives were given the opportunity to compare the new and old codecs, and most were said to have gone away satisfied. "There was an issue, it's been addressed and we're moving forward," Weston said.

Most industry analysts expect HD Radio to gather momentum more quickly than satellite radio has to date. Local broadcasters support the technology, mainly because it doesn't require a major investment on their part (less than $100,000 in most cases) and because it gives them a weapon in the battle against satellite radio.

"The broadcast industry is trying to match satellite radio in sound quality and keep their local listeners," said Jack Morgan, director of automotive in North America for Philips Semiconductors. "They want this technology."

Whether or not the technology's fuller sound will translate into dollars, however, is unknown. While most audio advancements have historically been welcomed by consumers, some innovations-such as quad speakers and AM stereo-have been notable failures. For that reason, most industry insiders say the as-yet-unknown marketing approach of HD Radio will play a big role in its ultimate success.

"The potential is certainly there for HD Radio to become a standard feature on all vehicles," said Yarosz of Delphi Delco. "But that's really going to be up to the consumer."

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