[opendtv] Re: TI Exec: Open Standards Crucial for Mobile TV

Have there ever been any indications that E-VSB will be used by anyone 
at all for any purpose?

- Tom


John Shutt wrote:

> Bert,
> 
> The correct terms are 1/2 rate and 1/4 rate, not 1/2 additional FEC.
> http://www.atsc.org/standards/a_53c_amend-1_corr-1.pdf
> 
> As you correctly state, at 1/2 rate, for 542 Kbps, you get 18.1 Mbps in the
> main stream.  You removed 1.3 Mbps from the main stream to get 542 Kbps in
> the robust stream.  lose 2 bits to gain 1 bit.
> 
> For 1/4 rate it's even worse.  To achieve 542 Kbps robust, you get 16.9 Mbps
> main stream.  You removed 2.5 Mbps from the main stream to get 542 Kbps for
> the robust stream.  You lose 4.5 bits to gain 1 bit.
> 
> As I understand it, with DVB-H, as implemented within a 6 MHz DVB-T stream 
> (as opposed to a
> dedicated 5 MHz DVB-H carrier as Crown Castle is planning in the US), the 
> DVB-H data is time sliced within the DVB-T bitesream, and is a straight 
> one-for-one bit usage.  The DVB-H data includes additional FEC, so for your 
> 542 Kbps you may need to use 25% more bitrate for the additional FEC data. 
> So you lose 677 Kbps from the main stream for a single DVB-H payload of 542 
> Kbps.
> 
> http://webapp.etsi.org/exchangefolder/en_302304v010101p.pdf
> http://www.dvb.org/documents/DVB-H_Outline.pdf
> 
> And I hate to point this out, but E-VSB may not even work very well.  E-VSB 
> was designed to improve reception, but not to increase battery life of a 
> portable device.  DVB-H is first and foremost a standard to save battery 
> power.
> 
> John
> 
> ----- Original Message ----- 
> From: "Manfredi, Albert E" <albert.e.manfredi@xxxxxxxxxx>
> To: "OpenDTV (E-mail)" <opendtv@xxxxxxxxxxxxx>
> Sent: Tuesday, March 29, 2005 6:33 PM
> Subject: [opendtv] Re: TI Exec: Open Standards Crucial for Mobile TV
> 
> 
>>Here's the E-VSB side. Maybe you can enlighten us on the
>>equivalent DVB-T/DVB-H tradeoff?
>>
>>I'm just picking two values of robust stream, and the
>>wide stream is supposed to be as robust as it is when
>>the entire band is wide stream.
>>
>>For 542 Kb/s robust stream using 1/2 additional FEC,
>>wide stream (2/3 FEC) is 18.1 Mb/s
>>
>>For 542 Kb/s robust stream using 1/4 additional FEC,
>>wide stream (2/3 FEC) is 16.9 Mb/s
> 
> 
> 
>  
>  
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