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Nick
08-17-07, 07:52 AM
"1.5 Mbps of transmitted signal would have 375 kbps of actual
video...sufficient for small devices such as cellphones and PDAs."


From HDTV Magazine.com: By Rodolfo La Maestra

A-VSB is a digital television (DTV) broadcast system for mobile purposes proposed to the ATSC in December 2005. During 2006 Sinclair Broadcast Group, Samsung Electronics, and transmitter manufacturer Rohde & Schwarz, joined efforts to successfully test DTV mobile reception at highway speeds.

A-VSB is expected to be included in the Advanced Television Systems Committee (ATSC) digital-TV standard by 1H07, and is backward compatible with 8-VSB the current DTV terrestrial system.

A-VSB, was previously simulated at NAB in April 2006, using forward-error-correction (FEC) "turbo-coding" for difficult signal environments, which used about one fifth of the transmitted bits for the actual video, the rest was to provide robustness so the signal is tuned well by the receiving device.

In other words, 1.5 megabits per second (Mbps) of transmitted signal would have only 375 kbps of actual video. That number of bits is considered sufficient for small devices such as cellphones and PDAs.

Sinclair's Buffalo digital station, WUTV-DT, received a temporary license for the join group to test A-VSB in a real-world environment, and it did successfully up to 150Mph using a Samsung YEPP portable digital media player to decode and display the MPEG-4 video carried within the turbo-coded streams transmitted from a server specially suited for the parallel transmission of 8-VSB and A-VSB. ...Full article @ HDTV Magazine.com (http://www.hdtvmagazine.com/articles/2007/08/mobile_dtv_rece.php)