Last week at CES in Las Vegas, three joint-development groups showed technology designed to allow broadcasters to send video to mobile devices, in an effort to increase stations’ multichannel offerings under the Open Mobile Video Coalition (OMVC). The OMVC was formed as a voluntary association of television broadcasters whose mission is to accelerate the development of mobile digital video in the United States.
The OMVC is composed of 20 members that own and operate over 450 commercial television stations, as well as the Association of Public Television Stations, which represents an additional 360 public television stations.
Two of the technologies, Mobile-Pedestrian-Handheld (MPH), a co-development of Harris and LG Electronics, and an A-VSB modulation scheme, developed by Samsung Electronics and Rohde & Schwarz, were announced last year at the NAB convention. Both showed prototype receivers at CES. A third entry was announced (although no working product shown) by Thomson and chipmaker Micronas. The companies will begin testing their system in March. This system is also being considered by OMVC members.
This year it was revealed that for a $125,000 investment, MPH broadcasters will be able to send programs that can be picked up by cell phones, laptops, GPS units and other mobile devices. Trials have already been conducted with FOX, PBS and Tribune. Kenwood has agreed to develop some in-car systems.
The A-VSB platform was developed as an open standard that builds on the current ATSC transmission standard to enable mobile TV reception while preserving backward compatibility with current TV services and receivers. It enables broadcasters to include multiple “turbo coded” mobile streams along with their backward-compatible main stream. In addition, the A-VSB technology facilitates the synchronization of broadcast signal timing of a ring of towers in a single-frequency network (SFN).
SFNs can improve broadcast quality with higher uniform signal strength throughout a service area, even in locations that normally would have their signals interfered with by obstacles such as hills or buildings.
A benefit to broadcasters in using DTV is that the data stream is compressed, allowing the transmission of several channels at the same time. However, due to limitations with the FCC’s cable access rules, broadcasters are only guaranteed that their primary signal will be carried over cable.
For more information, visit www.openmobilevideo.com.
