FCC OKs ‘NextGen’ Transmission Test

BALTIMORE—In what may prove to be the preface for the next chapter in U.S. television broadcasting, the FCC has authorized Baltimore television station WNUV-TV to begin testing a new transmission methodology that could pave the way for higher-definition video, enhanced multiplatform and mobile operations, and other innovations in over-the- air broadcasting.

The station was granted a six-month experimental authorization to conduct tests using orthogonal frequency division multiplex (OFDM) modulation as opposed to the present-day ATSC 8-VSB digital transmission standard. The station will conduct the tests in conjunction with several other broadcasters, equipment suppliers, and trade association groups, according to the original petition for the experimental license. WNUV is licensed to “Baltimore (WNUV-TV) Licensee, Inc.” and is operated by the Sinclair Broadcast Group under a Local Marketing Agreement.

In applying for the experimental authorization, the station stated to the FCC that it believed that “it will obtain the commitment of many others in the industry to participate in this effort. Discussions (under nondisclosure agreements) have already taken place.” WNUV said that it wanted to test the DVB-12 OFDM transmission technology already in use in some European nations, as it believes that this could set the stage for a new U.S. standard. (DVB-2 is the abbreviation for “Digital Video Broadcasting-Second Generation Terrestrial, and is an enhanced extension of the original DVB-T television standard. It was formally adopted in 2009.)

WNUV is a CW network affiliate, and in conducting the OFDM testing is taking a number of steps to minimize disruption of its normal network programming. Initial testing will take place only between 1:00 a.m. and 5:00 a.m. and the station will air its programming on a WBFF ancillary channel. Program feeds will also be provided to cable companies and other MVPDs who normally receive WNUV’s signal off-air.

Even though the FCC authorization states that the initial testing will be conducted in the early morning hours, it leaves the door open for expanding into the station’s daytime schedule later on, stating “…that minimum operating hours will be maintained during the few daytime experimental activities.”

WNUV stated in its application that it will be conducting the OFDM experimentation with only a limited number of receiving devices, and will share test results with the NAB, the Advanced Television Systems Committee and other organizations.

While the main thrust of the experiment may be DVB-T2, the FCC application stated that after completion of DVB-T2 testing, the station was planning to move into DVB-Lite (a subset of the DVB-T2 standard tailored for smaller mobile/handheld devices), DVBNGH (“Next Generation Handheld,” which is another variation of DVB-T2 with enhancements to aid mobile/portable reception), and also a “non-standard variant derived from experimental outputs.”

In applying for the OFDM testing authority, WNUV stated that the current ATSC transmission standard is geared towards delivering “large-format video to fixed receivers, while viewers are increasingly mobile and are viewing video on phones and tablets.” It views OFDM as a possible new TV transmission standard for the United States.

(Some readers may recall that in 1999 Sinclair pushed for acceptance of a form of OFDM for U.S. DTV transmission, and conducted shoot-outs between it and 8-VSB in Baltimore. The FCC acknowledged at that time that OFDM offered some advantages in terms of mobile and single frequency network operations, but favored retaining 8-VSB as a nationwide standard.)

Mark Richer, president of the ATSC, in commenting on the planned OFDM experimentation said that Sinclair was “very interested—as are others—in looking at a next-gen ATSC system.” Richer acknowledged that the ATSC is also working along those lines.

“We are going to be looking at all kind of technologies and we’re getting close to putting out a request for proposals for the physical layer [of the next-gen] system,” said Richer. “I expect that some of the proposals will involve OFDM.

“I know Sinclair is supportive of our process; I guess their plan is to test different technologies that could be used in ATSC 3.0. I personally think it’s good to see a broadcaster step up and do some experimentation to help develop the next system.”

When asked about the 1999 Sinclair COFDM testing, Richer said that he didn’t see much commonality between what was done then and what is happening now.

(TV Technology is indebted to sister publication Broadcasting & Cable’s John Eggerton for information used in the preparation of this account. Eggerton first reported about WNUV’s planned experiment Feb. 19.)

James E. O'Neal

James E. O’Neal has more than 50 years of experience in the broadcast arena, serving for nearly 37 years as a television broadcast engineer and, following his retirement from that field in 2005, moving into journalism as technology editor for TV Technology for almost the next decade. He continues to provide content for this publication, as well as sister publication Radio World, and others.  He authored the chapter on HF shortwave radio for the 11th Edition of the NAB Engineering Handbook, and serves as editor-in-chief of the IEEE’s Broadcast Technology publication, and as associate editor of the SMPTE Motion Imaging Journal. He is a SMPTE Life Fellow, and a Life Member of the IEEE and the SBE.