If anyone thought ATSC DTV transmission to mobile and handheld devices wasn't going to happen, the demonstrations at this year's International CES proved them wrong. Two of the proponents (Samsung, with A-VSB, and LG Electronics, with MPH) that submitted proposed standards to ATSC for consideration as the ATSC M/H standard had prominent CES displays.
There they showed reception of signals broadcast from two Sinclair stations. The receivers weren't tethered experimental boxes. Both manufacturers showed video on cell phones the same size as those currently being sold for reception of existing services such as Verizon's V-Cast.
Other receivers were shown, including some by Samsung that could eventually be included in MP3 players or portable game machines. LG displayed a larger, portable DVD player-sized hand-held with additional functions, including GPS. Kenwood Electronics had a working demonstration of an MPH in-car receiver using the LG chip.
When I asked how long it would take to get the receiver to market, the Kenwood representative pointed to their existing in-car DTV receivers for other standards and noted that the differences weren't that great. He said Kenwood would be able to provide receivers relatively soon after ATSC adopts a standard.
Both Samsung and LG showed thumb-drive-sized USB tuners for laptops. While the performance of USB receivers based on the legacy ATSC standard continues to improve, a corrected signal to noise ratio (SNR) of at least 15 dB is needed for reception. With the proposed ATSC M/H standards, the theoretical SNR limit drops to less than 6 dB when more robust coding is used. This would allow reception of the robust streams in offices and other locations where it may be difficult to achieve a 15 dB SNR. It should also do well on commuter trains.
Receivers alone are not enough. Stations will likely need to modify or replace existing ATSC exciters to add mobile/handheld transmissions and to support the single frequency networks in areas shadowed by buildings or terrain. The good news is all the manufacturers I spoke with are interested in backing an eventual mobile/handheld standard ATSC. Look for this to be a major item at The NAB Show in April.
On Tuesday (Jan. 8) at CES, the Open Mobile Video Coalition announced trials of the system in several markets starting soon. (This group includes the Association of Public Television Stations, representing 360 public television stations, along with broadcast groups representing more than 450 commercial stations.) Manufacturers including LG Electronics, Samsung, SES-Americom, Nokia, MobiTV, Rohde & Schwarz and Harris Corp. are supporting the trials. The program material for the tests will be aggregated by SES-Americom. SES-Americom will also provide encoding, security and program guide services for the programming, which will be distributed to the test stations using its IP Prime network.
From conversations with different manufacturers, it was clear there was a lot of interest in the success of broadcast digital mobile video. They will certainly be fighting for their own version of the "best" standard. However, it appears clear that whatever standard or combination of standards is selected, most, if not all, manufacturers will support it.
Supporting mobile/handheld TV to the extent needed to match cell phone carriers coverage will involve more than simple transmitter modifications. Transmit antenna changes may be necessary, as well as the addition of low-power on-channel booster and single frequency network sites to fill in coverage holes. Cable TV and satellite TV won't provide TV station's signals on cell phones, or in cars not equipped with large and expensive satellite tracking antennas. With the increased interest in "wireless TV", RF Report readers should find a lot to talk about at NAB this year!
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