Skip to main content

CMMB OK for cellular, not for broadcast

CMMB America, together with Canadian technology provider Unique Broadband Systems (UBS) and Hong Kong affiliate CMMB Vision, announced the successful demonstration of Converged Multimedia Mobile Broadcasting (CMMB) mobile TV signals for the first time over cellular network frequencies in a trial demonstration near Denver.

The demonstration represents the first United States-based field test for CMMB and signifies the company’s attempt to position CMMB for its commercial launch of services in the U.S. market. The company says the results validate CMMB’s ability to cohabitate with cellular technologies as well as its superior coverage over varying line of sight and non-line of sight environments.

Said Fred Slater, vice president of operations for CMMB America, said, “We were happy with the system’s performance during the demonstration and grateful for the cooperation and support provided by UBS in meeting our requirements.”

CMMB America plans to conduct further technical and market-specific tests tailored to U.S. market conditions, including the use of multiple UHF radio and S-band satellite frequencies. CMMB America also plans to integrate CMMB with 3G/LTE networks to provide converged services.

Broadcast Engineering earlier reported on the potential use of CMMB technology for U.S. mobile TV. In November 2010, Greg Herman, president of, presented to the FCC's OET staff a live OTA demonstration of CMMB (shown in the image above). The presentation included the simultaneous transmission of seven video streams to some 20 working consumer devices.

The FCC staff at the demonstration included Rebecca Hanson, senior advisor/special counsel in the Media Bureau; Julius Knapp, chief of the Office of Engineering and Technology; and five OET staff members. The participants learned that CMMB technology, which relies on OFDM-based modulation, already is being deployed in more than 330 Chinese cities, and that a robust ecosystem, including numerous consumer receivers, already exists.

Herman called CMMB a significant improvement over the decade-old 8-VSB modulation scheme. According to Herman, CMMB is approximately four times more efficient in terms of digital throughput compared to ATSC-M/H for the delivery of mobile broadband-broadcast services. A video of the demonstration is available here.

Normally such a request would receive an OET staff-level approval. Instead, the staff bumped Herman’s request up to the chairman’s office. And despite what appear to be good reasons to approve his request for a temporary test authority, the chairman refused.

While broadcasters’ future may depend on mobile, that has taken a back seat to another pending FCC action. As will be reported in the April issue, the primary issue on the minds of broadcasters is spectrum auctions. The commission's National Broadband Plan and its implications for mobile DTV are what have broadcasters’ attention.

According to Scott Barella, vice president of technology and business development for LARCAN, broadcasters increasingly are asking why they are being asked to relinquish spectrum rather than being given the freedom to employ other modulation techniques, such as CMMB or DVB-T2, which could position them to deliver free-to-air TV and meet the goals laid out in the National Broadband Plan.

While the FCC refused a broadcast-group application to test CMMB technology, it seems to have no problem approving similar tests for a cellular-focused application of the technology.

It is no great leap to view Chairman Genachowski as single-mindedly focused on reaping a treasure trove of billions of dollars by selling off broadcast spectrum. Woe be to anyone, or any technology, that steps between him and his plan.