Most Popular Articles
IBOC Update - Jan 14, 2004
- Kenwood, Panasonic, Onkyo, JVC, and Visteon Premiere HD Radio Receivers
- Iowa is Kick-off Point for HD Radio Receiver Sales
- NPR Provides In-depth look at Tomorrow Radio to NRSC
- FCC Considers Use of Separate Digital/Analog FM Antennas, Seeks Comments and Evaluations for Possible Rulemaking
- An Introduction to the New Language Surrounding HD Radio
- Delphi, Panasonic and Visteon Demo HD Traffic Information Systems at CES
- Audio Processing Manufacturers: There's More to HD Radio Than Transmitters and Antennas
To receive these articles twice a month in your e-mail, subscribe to the IBOC Update - Insight on HD Radio e-newsletter. Click here to subscribe.
Kenwood, Panasonic, Onkyo, JVC, and Visteon Premiere HD Radio Receivers
CES - The long awaited debut of HD Radio consumer receivers arrived
as industry leaders displayed new offerings from three major consumer
manufacturers at the CES in Las Vegas on January 7.
"CES brought you a first look at this promising technology in 2001. Today marks a historic moment for the radio broadcast and consumer electronics industries," said Consumer Electronics Association (CEA) President and Chief Executive Officer Gary Shapiro. "The transition of the world's last major medium, AM and FM radio, from analog to digital is now fulfilled with the availability of HD Radio receivers for consumers."
Manufacturer Kenwood says it will be shipping its KTC-HR100 tuners this month. JVC's offering, a single-DIN model, is expected to be available during the spring, as will be Panasonic's CB9900U. Onkyo claims it will be introducing several models this year and plans to offer a modular system approach that allows consumers to add features as desired.
Iowa is Kick-off Point for HD Radio Receiver Sales
Cedar Rapids, IA - America's heartland became the starting line in
the race to deploy HD Radio, as consumer electronics giant Kenwood
America announced the first sale of a consumer receiver in Cedar
Rapids, IA, last week. On Monday, January 5, 2004, Nathan Franzen
purchased a Kenwood KTC-HR100 HD Radio tuner at Ultimate
Following installation in his 2001 Pontiac Grand Prix, Franzen tuned in to IBOC broadcaster KZIA-FM, Z102.9, and became the first American consumer to experience the new sound and features of HD Radio. The Cedar Rapids outlet of Ultimate Electronics also claims the distinction of being the first retailer to sell a high-definition television nationally.
NPR Provides In-depth Look at Tomorrow Radio to NRSC
On Friday, Jan. 9, a research initiative by National Public Radio,
in conjunction with technology sponsors Kenwood America and Harris
Corporation, presented the results of advanced HD Radio field tests to
a meeting of the NRSC in Las Vegas, Nevada. The project, dubbed
Tomorrow Radio, was conceived with an eye to exploring
multi-channel broadcasting possibilities for NPR's approximately 750
member/affiliate stations across the United States. The tests,
conducted over HD radio signals originating from NPR affiliate stations
KALW-FM, San Francisco, KKJZ-FM, Long Beach, and WETA-FM, Washington
DC, successfully demonstrated the viability of transmitting
supplemental audio channels (SAC) along with a main audio program
"Multicasting on SACs is real, and it works better than we anticipated," said Mike Starling, NPR's vice president for engineering and operations. "HD radio is no longer just a hypothetical construct. Tomorrow Radio is here today."
The Tomorrow Radio approach capitalizes on HD Radio's 1kb/s scalable architecture. With an FM signal that is capable of delivering a maximum 96kb/s stream of program audio data, multiple audio channels may be made available at reduced bit rates. Combined with increasingly sophisticated low bit-rate encoding algorithms such as AAC, a broadcaster could format a multi-channel signal in a variety of ways, depending upon the nominal performance requirement for each channel's program audio.
Tomorrow Radio's fall/winter 2003 field tests involved four NPR member stations along with NPR's Tomorrow Radio sponsors Kenwood USA (who provided the test receivers and mobile test lab for the field test) and Harris (who provided transmission equipment to each of the participating field test stations). Field tests were done over seven weeks, with testers spanning 7,500 miles and collecting over a million discrete data points. The testing is said to have documented excellent city-grade coverage for the all-digital SAC under experimental licenses from the FCC.
"This technology is key for public radio," Starling continued. "Having the ability to broadcast multiple channels using existing spectrum means that nonprofit radio stations can do more with what they already have, and lessens the pressure to compete for scarce and expensive new frequencies. And listeners could be the biggest winners, with even more public radio and services at their fingertips."
Tomorrow Radio Project expenses were incurred by NPR, NPR member stations, along with sponsors Harris Corporation. and Kenwood USA. When combined, the total cost of this round of SAC field tests is estimated to have exceeded $1 million.
NPR and Tomorrow Radio sponsors will share the 2003 field test results with the FCC in the next few weeks and seek authority for NPR member stations to begin initial SAC broadcasts. Kenwood USA has indicated product support will promptly follow FCC authorization of the new services.
NPR contracted with consulting engineers Hammett & Edison for test plan oversight, data collection and certification of final results. The Corporation For Public Broadcasting collaborated on test objectives and also provided significant financial support for the Tomorrow Radio Project tests.
FCC Considers Use of Separate Digital/Analog FM Antennas, Seeks Comments and Evaluations for Possible Rulemaking
In a public notice issued in December, the FCC indicated that it
seeks comments on the use of separate, co-located antennas to transmit
the digital and analog signals separately. The Public Notice concerning
this configuration, known as "space combining," was triggered by a
field test report submitted by an NAB sponsored ad hoc technical group
on July 24, 2003.
This action is significant because the FCC had previously required the use of a single antenna fed with a combined digital/analog signal. Potentially, a ruling favorable to allowing space combining would allow some broadcasters to avoid having to implement the use of lossy high-level combiners, which might force some broadcasters to prematurely replace existing analog transmitters with higher capacity models or new low-level combined transmitters. In its release the FCC noted that it would tentatively approve separate antenna operation providing the following criteria are met:
The digital transmission must use a licensed auxiliary antenna;
The auxiliary antenna must be within three seconds of latitude and longitude of the main antenna; and
The height above average terrain of the auxiliary antennas must be between 70 and 100 percent of the height above average terrain of the main antenna.
The NAB report also recommended that the Commission authorize use of antennas specially designed with interleaved or stacked elements for analog and digital signals. This is based on the fact that a fixed ratio of analog to digital signal (20dB) is required for proper performance of FM IBOC receivers, and a concern that dissimilar analog/digital antenna radiation patterns might cause unacceptable ratio variation in the field.
A complete copy of the NAB report can be viewed at www.fcc.gov/cgb/ecfs under MM Docket No. 99-325. Although the deadline for further comments has already passed, interested parties may submit replies to comments on the test results, conclusions, and recommendations in the report of the NAB ad hoc technical committee comments on or before January 23, 2004. Replies should specifically reference the Public Notice. Comments and reply comments may be filed electronically at www.fcc.gov/cgb/ecfs, or on paper (an original and four copies) with the Commission's Secretary, Marlene Dortch, Federal Communications Commission, 236 Massachusetts Avenue, NE, Suite 110, Washington, DC, 20002.
|HD Radio Terminology|
An introduction to the new language surrounding HD Radio
: An FM IBOC transmission system that combines the analog and
digital signal at the exciter level, and amplifies the combined signal
via a wide-band, high linearity intermediate and final power
high-level combining: An FM IBOC transmission system that combines the outputs of discrete analog and digital transmitters through the use of large scale isolators and combiner.
space combining: An FM IBOC transmission system that uses co-located but separate antenna elements to transmit the outputs of discrete analog and digital transmitters.
interleaved antennas: An antenna array designed for space combining of IBOC FM analog and digital signals. Theoretically, identical style antenna elements are mounted on a common axis in staggered order. Digital and analog elements are cross-polarized to reduce mutual coupling.
|Technology and Applications|
Delphi, Panasonic and Visteon Demo HD Traffic Information Systems at CES
CES - Reminding the broadcast industry that IBOC is about more than
digital audio, automotive electronics developers Delphi, Panasonic, and
Visteon teamed with Ibiquity Digital to demonstrate in-vehicle text and
navigation information systems at the 2004 Consumer Electronic show in
Las Vegas. With data providers Navigation Technologies and TrafficCast
transmitting real-time traffic and navigation information via Vegas
IBOC broadcaster KSTJ-FM, Delphi hardware displayed text-based traffic
reports in a Pontiac Montana, while real-time map displays highlighting
trouble spots were overlaid on a Panasonic GPS navigation system
enabled with NAVTECH maps and a Visteon multimedia driver information
"This telematics demonstration shows one of many innovative ways the FM band can be used to transmit digital information at a fraction of the cost of conventional wireless systems," said Robert Struble, president and chief executive officer, Ibiquity Digital. "As we continue to work with service and content providers, we foresee numerous telematics applications derived from HD Radio digital broadcast technology."
KTSJ is operated by Beasley Broadcast Group. The station uses a Broadcast Electronics FMi 201 IBOC transmitter, BE FXi 250 exciter, and BE FSi 10 IBOC signal generator into a three-bay Shively 6813-3 antenna separate from the main analog broadcast. The station is broadcasting IBOC under an experimental permit, pending the FCC's rulemaking on the use of separate antennas for digital service.
Audio Processing Manufacturers: There's More to HD Radio Than Transmitters and Antennas
Two leading audio processing designers, Frank Foti of Omnia Audio,
and Robert Orban of Orban/CRL, have recently released documents aimed
at helping prepare broadcasters for some key elements of IBOC
conversion that may get overlooked in the initial planning/budgeting
phases. A key issue, according to both authors, is the need for
broadcasters to provide analog and digital program streams that are
both time aligned and audio processed to achieve a similar "signature"
or characteristic sound, between the two signals. This necessity
results from the fact that HD Radio receivers blend or crossfade
between the analog and digital audio streams whenever a listener turns
on the receiver, switches stations, or encounters momentary digital
dropouts due to terrain/signal factors. Thus, digital and audio streams
that don't match well are likely to prove distracting or
Things are further complicated by the fact that audio processing techniques for analog FM stereo and bit-reduced digital audio are substantially different. This means that that programmers or engineers trying to achieve a reasonable match between a new digital processor and a station's existing analog processor are destined to end in frustration. The answer? Buy a processor from your favorite manufacturer that combines both functions. The cost will be higher than a stand-alone digital processor, but the results could be worth the difference and more. Both Orban and Omnia are offering these integrated products, and it's likely that other providers will follow suit as more broadcasters commit to HD Radio conversion.
But for the budget-minded broadcaster this all begs a question: What to do with the old audio processing equipment? Trade-in or sale is certainly one possibility, but Omnia's Foti suggests placing it in the studio monitoring chain. Because of an HD Radio characteristic known as latency, the time needed for buffering and reassembly of the digital audio signal, HD Radio will introduce a real-time delay between the studio and off- air signal of nearly six seconds. This means that studio operators or DJs will no longer be able to reference an off air signal. By placing the old analog processing in the in-studio monitoring chain, on-air talent will still hear themselves in the post-processed world. In Foti's words, "the HDC Radio system has the potential to provide an exciting experience for your listeners…but the days of plugging a console into the airchain and monitoring off of a tuner are probably gone for good."
Acceptable Use Policy blog comments powered by Disqus
[an error occurred while processing this directive]
Today in Radio History
The history of radio broadcasting extends beyond the work of a few famous inventors.
EAS Information More on EAS
The feed provides feeds for all US states and territories.
Need a calendar for your computer desktop? Use one of ours.
Information from manufacturers and associations about industry news, products, technology and business announcements.
When Northern Community Radio set out to build a new community radio station in rural northern Minnesota 38 years ago, naysayers said that it would be broadcasting “only to a bunch of gophers
Browse Back Issues[an error occurred while processing this directive]
Also in the July Issue
- Trends in Technology: Robust IP STL
- LPFM on The March
- RF Engineering: Modern Modulation Techniques
- Field Report: Tascam TH-2000 Headphones
- Battery Maintenance: Testing and Charging