IBOC Update - Feb 11, 2004

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Analog SCA Operation Still Viable for HD Radio FM Broadcasters

FM broadcasters converting to IBOC operations may want to think twice before throwing away their analog SCA generators, according to a Hammet and Edison report on NPR's extensive testing of HD Radio for the Tomorrow Radio project. The question of whether or not analog subcarrier services can function in a fully populated HD Radio environment is a significant one for many FM broadcasters. Typically, these stations may lease or donate their subcarrier bandwidth to other organizations or business entities. Having to give up those subcarriers would be problematic because of the lost revenue or displacement of valued community services, such as radio reading for the blind. This is an issue of particular sensitivity to NPR affiliates who farm out subcarriers to community organizations.

The test report, soon to be presented to the FCC, involves data taken from actual field measurements of three NPR affiliate stations operating HD Radio transmission systems. Observations were made involving both 67kHz and 92kHz analog SCA transmission occurring simultaneously with the IBOC digital signal.

According to Lyle Henry, CPBE, a specialist in analog SCA operation, the report indicates that existing analog subcarriers can coexist in an IBOC environment, providing that the SCA receivers in use have reasonably good RF performance. Henry also notes that HD Radio operation on first- and second-adjacent channels might cause somewhat more interference than that experienced in an analog FM environment, but only under unusual propagation conditions.

The Hammet and Edison report is available at
www.npr.org/euonline. Look for a summary and report on the NPR study in the March issue of Radio magazine.


Clear Channel's Littlejohn Named to Ibiquity Board of Directors

Columbia, MD - Feb 10, 2004 - Jeff Littlejohn, senior vice president of engineering for Clear Channel Broadcasting, has been appointed to Ibiquity's board of directors.

In his role with Clear Channel, Littlejohn oversees all technical aspects for the radio division. He is a member of several industry committees including the National Radio Systems Committee and various groups within the National Association of Broadcasters. Prior to joining Clear Channel, Littlejohn was the Director of Engineering for AMFM, Inc. and Chancellor Broadcasting.

"Clear Channel was one of the early investors in Ibiquity and has always been a strong supporter of HD Radio technology. As such, we have worked closely with Jeff Littlejohn for a number of years," said Bob Struble, president and CEO of Ibiquity Digital.

"HD Radio is the most revolutionary change in our industry since the introduction of FM more than 40 years ago. The combination of its dramatically improved sound quality and wireless data services will transform the radio experience - for both broadcasters and consumers - in ways never thought possible," said Littlejohn. "I look forward to working with the Board and drawing from my experiences to ensure a speedy and successful rollout of HD Radio technology."

FCC Update

Broadcasters, Ibiquity Optimistic on FCC Authorization of FM Dual-antenna Operation

In phone interviews this week, spokespersons for Ibiquity and broadcast giant Clear Channel Communications said they are hopeful the FCC will permit dual-antenna operation for HD Radio FM broadcasters in the very near future. Clear Channel VP of engineering Jeff Littlejohn and Ibiquity VP or marketing Dave Salemi both expressed confidence that the FCC will soon sweep aside a significant economic hurdle to FM HD Radio implementation by allowing broadcasters to operate with separate antennas for their analog and digital transmitters. This would be a major breakthrough for broadcasters, many of who have expressed concerns about the expense of having to purchase and install large, costly high-level combiners in order to operate into a single main antenna. Currently, a special temporary authority, or STA, is required from the commission to operate in the dual-antenna mode.

If the FCC gives its blessing, FM broadcasters might be able to simply connect a digital transmitter to an existing licensed auxiliary antenna and begin operation, saving tens of thousands of dollars while preserving the station's current analog operating parameters. An additional piece of equipment called a circulator might be required on the output of some digital transmitters to prevent excessive analog signal from coupling back in to the digital power amplifier, but it is relatively small and inexpensive when compared to a high-level combiner.

Additional savings for broadcasters will result from the fact that high-level combiners require higher output power from analog transmitters, forcing some broadcasters to replace existing units with higher power models. By eliminating the need for a combiner, broadcasters will be able to retain their current analog equipment with virtually no modification.

To be eligible for dual-antenna operation, broadcasters will likely have to use a licensed auxiliary antenna located within 3 seconds of the coordinates of the main (analog) antenna at a height falling within 70 percent to 100 percent of the height above average terrain of the existing main antenna.

Littlejohn said that the company has a number of FM outlets ready to begin operation once the FCC formally grants its approval. For Ibiquty's part, Salemi said the company was grateful for the unanimous support the proposal has received from the broadcast community and is looking forward to adoption of the new standards.

Eye on IBOC

Tale of an IBOC Early Adopter

Elyria, OH - In broadcasting, it's often said that those that embrace the newest technologies may be operating on the bleeding rather than leading edge. But for locally owned radio groups like Elyria-Lorain Broadcasting in northeast Ohio, remaining competitive with massive national conglomerates such as Clear Channel and Infinity means having to strap on the new technology as quickly as possible, sometimes before completion of the debugging process. Such was the case when WNWV-FM, Elyria-Lorain's smooth jazz outlet, undertook the challenge to become northeast Ohio's first HD Radio broadcaster more than one year ago.

Gary Kniseley, senior manager of the radio group, recalled how the company's equipment vendor, Harris Corporation, took time during the purchase process to provide exact physical layouts and technical requirements for the HD Radio installation process. The result was a relatively glitch-free modification of the WNWV transmitter facility by chief engineer Glenn Smith. As it rolled out, the IBOC upgrade involved not only the addition of a digital transmitter and exciter, but also a high-level combiner capable of handling more than 8kW of analog signal. Yet even with the addition of extensive RF plumbing and some creative floor plan modifications, Kniseley wryly observed that the only truly significant issue to surface occurred on May 7, 2003 - the day that the IBOC transmitter was signed on for the first time.

The problem? As it turned out, the station was so far ahead of the adoption curve that no HD Radio receivers were yet available, making it impossible to monitor the station's digital signal. That problem was overcome a couple of weeks later with the arrival of a loaner receiver from Ibiquity. That unit has since been replaced by a Kenwood KTC-HR100 HD Radio receiver mounted in a portable case, allowing it to be demonstrated on the bench or in vehicles.

In summing up, Kniseley said that he and his staff take pride in being the first to take the HD Radio plunge, but are looking forward to the day when there are a lot more "swimmers" in the water.

HD Radio Terminology

An introduction to the new language surrounding HD Radio

common amplification

: Applies to IBOC transmission systems that use a common RF power amplifier feeding a common antenna for both the analog and digital signal. Also referred to as "low-level combining."

separate amplification: Applies to IBOC transmission systems that use separate RF power amplifiers operating into a high-power combiner or separate antennas for the transmission of analog and digital signals.

latency: The time required for an IBOC receiver to acquire, buffer and decode the digital program signal. Typically, this period may be up to 6 seconds in length. For this reason, the analog audio is usually deliberately delayed so as to match the digital signal in time.


Omnia Audio Adds Two IBOC Products to Line

Cleveland, OH - Omnia Audio has added new AM and FM HD Radio audio processors to its existing family of audio processor offerings. According to company press releases, the new 5EX HD+AM borrows advanced technology from the company's Omnia-6EX processor, but also provides a number of specialized features tailored to improving analog AM analog performance as well as that of the digital signal. "A lot of knowledgeable broadcasters are saying that HD Radio will benefit AM stations the most," says Omnia president Frank Foti, who feels that the improved sound of HD Radio's HDC codec will breathe new life into Americas oldest broadcast band.

Complimenting the new AM product is the introduction of the Omnia-5EX for FM, featuring paired parallel processing paths - one optimized for conventional broadcasting, the other for DAB, HD Radio, webcasting or digital satellite systems.

Ethernet and parallel control ports are standard on both products, as is Linux-based front panel control software. Omnia Audio says that 5EX is now shipping, with the 5EX+AM expected to follow shortly.

Inside RF

Broadcast Electronics to Hold HD Radio Seminar at NAB2004

Quincy, IL - Broadcast Electronics will host another in its series of HD Radio seminars in Las Vegas during the NAB2004 convention in April. The seminar will take place on the afternoon of Sunday, April 18, at a yet-to-be-announced place and time. BE has conducted more than 30 seminars around the country during the past two years. The Las Vegas seminar will cover a number of topics, including discussions on new data delivery systems, present and future; transmission technologies; HD Radio status and updates; installation and integration; reports from the field; and antenna technology and development.

There is no charge to attend the seminars, but reservations are required. To register, send an e-mail to

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