On Thu, 08 Nov 2007 00:40:50 +0000, MRW wrote:

I'm not sure where else to ask this question, but I guess since this group
deals with antennas then maybe you guys are familiar with this. This is
regarding HDTV broadcast:

"Because of the 6 MHz. channel bandwidth allocated, each channel will only
support a data rate of 19.2 Mb/sec."

How is 19.2Mb/sec calculated?

Thanks!


I would guess that with the 8vsb modulation schema that was selected, they
took the maximum cymbal rate that would fit into a 6Mhz channel, then
selected a FEC rate that would sustain a reliability link budget. This
dictated the bitrate of 19392659bps

http://www.broadcast.net/~sbe1/8vsb/8vsb.htm
http://en.wikipedia.org/wiki/8VSB#Bi...ission_systems

Other modulation schemes exists that would fit into a 6Mhz channel such as
256QAM but theory dictates that the higher the bitrate, the more energy
per bit that is required at the receive end to make a usable signal.