DIGITAL FM BEAT ANALOG IN ALL TEST CRITERIA, IBIQUITY DECLARES
Declaring that “the stage is set” for commercial rollout of in-band, on-channel (IBOC) digital audio broadcasting (DAB) radio next year, iBiquity Digital Thurs. hailed results of its digital FM tests submitted day earlier to National Radio Systems Committee (NRSC) as scoring high marks in crucial areas of audio quality, robustness of coverage and compatibility with existing FM infrastructure.
Sign up for a free preview to unlock the rest of this article
Communications Daily is required reading for senior executives at top telecom corporations, law firms, lobbying organizations, associations and government agencies (including the FCC). Join them today!
Lab tests were conducted at Advanced TV Technology Center in Alexandria, Va. Subjective listening tests involving 600 sound samples and 120 listeners were done at Dynastat, Austin evaluation firm. System was field-tested at 8 FM stations. IBiquity Pres.- CEO Robert Struble said NRSC was expected to take 90 days to evaluate test results and submit report to FCC. He said Commission had indicated it would act quickly on NRSC recommendations.
First DAB broadcast equipment is expected to be unveiled commercially at April 2002 NAB convention, after which stations in Chicago, L.A., N.Y., San Francisco, Seattle and Miami are expected to begin full-time transmissions. Struble said first significant assortment of receivers was expected to be introduced at Jan. 2003 Consumer Electronics Show in Las Vegas. “Definitive conclusion” of test results is that iBiquity digital FM system “provides outstanding digital coverage and superior audio quality, eliminates audio impairments and maintains compatibility with the existing analog service,” Struble told reporters in teleconference. “We believe this test program to be the most comprehensive in U.S. broadcast history,” he said. He said IBOC “has been a long time coming, but the future really is now, and we encourage both the NRSC and the FCC to act quickly to speed IBOC’s rollout.”
Test results “definitively establish” superiority of IBOC audio quality over analog, Struble said. IBOC sound quality was superior to analog across all musical genres and test conditions, he said. “Quite simply, digital sounds better than analog in all cases.”
System also fared well in service coverage evaluations, Struble said. Field tests conducted on 8 FM stations representing cross-section of classes and conditions “demonstrates the extensive service area IBOC provides,” he said. “Operating at only 1% of the power of analog FM, IBOC has proven to be comparable to analog FM coverage with a robust signal producing CD-quality audio in all the markets served.” System also excelled on multipath performance, Struble said. For example, he said, in Manhattan, “where multipath significantly degrades FM reception,” digital IBOC “performed flawlessly” when field-tested at WNEW-FM talk radio. He said “outstanding coverage” also was achieved in San Francisco, which he said was considered one of more “difficult” environments for FM reception.
In subjective listening tests, iBiquity system also received “consistently higher scores” than analog in signal robustness, Struble said: “Digital performance remained strong even as impairments became more severe, while analog performance progressively degraded. This means that digital can turn areas of subpar quality into areas of superior digital quality.” He said digital FM passed tests with flying colors in important area of compatibility: “The IBOC system will have no meaningful impact on existing analog broadcast operations,” meaning digital system causes no interference with “host” IBOC stations or their first or 2nd adjacent “neighbors.”
Struble said iBiquity tests were continuing on digital AM system, with results expected to be ready for submission to NRSC by Oct. or Nov. He said iBiquity wanted to give NRSC “something to chew on” in terms of FM test results while AM evaluations were still proceeding.