Helps but is there a discrepancy here with the numbers in the article. At .3 Mbs at 1/4 at 18% would that be a total bit cost of 1.67 Mbs and the same for .6 Mbs at 1/2 at 36% for a bit cost of 1.67 Mbs or a total of 3.34 Mbs. They claim to have used 4.5 Mbs. Something I am missing? There is an extra 1.16 Mbs they used for something. Or is my math off somewhere? Bob Miller On Thu, Aug 7, 2008 at 3:01 PM, Mark A. Aitken <maitken@xxxxxxxxxx> wrote: > To end the 'long enuf' confusion, and without getting down to the 'nits' > regards (slight, electable) variables inside of the robust modes and > variables related to the "embedded" training, the rounded off numbers for > total efficiency (which is almost flat across the amount of bits used) for > modes are: > > 18% for 1/4 rate turbo > 36% for 1/2 rate turbo > > Does that help...? > > Mark > the one who should know... > > On 8/7/2008 12:08 PM, Bob Miller wrote: > > That is what I would like to know. How far was I off last year when in > technical ignorance but from a good source I put out numbers on what > one 8-VSB mobile modulation would cost in bits. What are the numbers? > What is the overhead and what is the % of bits that are real at what > robustness levels? > > Anybody care to compare to DVB-T or H or CDMB-T or is it a big secret > because it is so bad. > > Bob Miller > > On Thu, Aug 7, 2008 at 11:24 AM, <dan.grimes@xxxxxxxx> wrote: > > > What is the reason for only getting one 600 Kb/s and one 300Kb/s channel out > of 4.5 Mb/s? Are the rest of the bits required for overhead or did they > just not fill all the M/H channels possible in the 4.5 Mb/s subchannel > bandwidth? > > Dan > > > > Tom Barry <trbarry@xxxxxxxxxxx> > Sent by: opendtv-bounce@xxxxxxxxxxxxx > > 08/06/2008 08:41 PM > > Please respond to > opendtv@xxxxxxxxxxxxx > To > opendtv <opendtv@xxxxxxxxxxxxx> > cc > Subject > [opendtv] From Broadcast Engineering - WRAL tests mobile DTV > > > > > Supposedly from Broadcast Engineering though I copied it from AVS > <http://www.avsforum.com/avs-vb/showthread.php?t=1056025>. I'm not sure > I understand it correctly but it looks like they got a total of 900 > kbps (2 channels, 300+600) after error correction overhead from using a > total of 4.5 mbps of the channel bandwidth. > > - Tom > > --------------------------------------------------- > From Broadcast Engineering - WRAL tests mobile DTV > Broadcast Engineering Mobile TV Update > > WRAL tests mobile DTV > > Users in Raleigh-Durham reported reliable signal reception in most parts > of the station's existing coverage area. > > WRAL-DT, the CBS affiliate in Raleigh-Durham, NC, owned by Capitol > Broadcasting Company (CBC), conducted a series of mobile DTV tests last > week using the Mobile-Pedestrian-Handheld (MPH) system promoted by > Harris Broadcast and others. Hosted by CBC's New Media Group, the tests > featured seven handsets given to station executives living in different > parts of the state. Users reported reliable signal reception in most > parts of the station's existing coverage area. > > To kick off the July 21-25 trial, the station hosted a reception last > Tuesday in which about 50 participants were driven in a bus around the > area with prototype LG Electronics mobile handsets that featured > MPH-compatible reception chips inside. Signal reception of two channels > (half rate at 600kb/s and one-quarter rate at 300kb/s) using about > 4.5Mb/s (including turbo coding) of the station's 19.4Mb/s on-air DTV > stream was reportedly strong everywhere they went during the 10-minute > ride — even at 70 miles per hour. > > The goal of the service, according to John Harris, WRAL's director of > programming, is to extend the reach of the station's television channel, > and make it available everywhere our viewers are. The initial plan is to > simulcast the on-air DTV signal. WRAL-TV broadcasts CBS network and its > own local programming in the 1080i HDTV format as well as in SD digital. > > "We're excited about the possibilities," John Harris, WRAL's director of > programming, told Broadcast Engineering. "The priority is to offer > WRAL's TV signal in another way, in another place. I took one [handset] > east of the station and I just kept driving until the signal dropped > out. I got pretty far before that happened, so I can see the potential > of this service." > > LG Electronics, Zenith Electronics and Harris, all proponents of the MPH > scheme, helped out with the field trials. WRAL-DT uses a Harris Sigma > CVD UHF transmitter, with an MPH module, for the weeklong test. > > In a statement, James F. Goodmon, CEO of CBC, said "mobile DTV > broadcasting enables WRAL to better serve our viewers, communities, and > advertisers by providing a strong combination of anywhere access, > two-way communication, and mobility." > > In 1996, Harris worked with WRAL-DT as one of the first DTV stations in > the country. Two years later, when John Glenn made his historic return > to space, Harris worked with WRAL to conduct the first live HDTV > broadcast of a space shuttle launch to audiences nationwide. Now, the > station is the first to promote mobile DTV service in the state of North > Carolina. WRAL predicts that more than 200 million portable devices will > be sold in 2008, although few if any will have the necessary MPH > reception chips inside. > > WRAL-TV and Capitol Broadcasting Company are part of the Open Mobile > Video Coalition (www.openmobilevideo.com), a nationwide group of > broadcasters driving the deployment of mobile digital broadcast > television. Commercial deployments are forecast for 2009. The group > hopes to have an established standard available to broadcasters by the > February 2009 analog shutoff date. > -- > Tom Barry trbarry@xxxxxxxxxxx > > > > > ---------------------------------------------------------------------- > You can UNSUBSCRIBE from the OpenDTV list in two ways: > > - Using the UNSUBSCRIBE command in your user configuration settings at > FreeLists.org > > - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word > unsubscribe in the subject line. > > > > > > > > ---------------------------------------------------------------------- > You can UNSUBSCRIBE from the OpenDTV list in two ways: > > - Using the UNSUBSCRIBE command in your user configuration settings at > FreeLists.org > > - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word > unsubscribe in the subject line. > > > > -- > > Regards, > Mark A. Aitken > Director, Advanced Technology > > <>< <>< <>< <>< <>< <>< <>< > > =================================== > Sinclair Broadcast Group > 10706 Beaver Dam Road > Hunt Valley, MD 21030 > =================================== > Business TEL: (410) 568-1535 > Business MOBILE: (443) 677-4425 > Business FAX: (410) 568-1580 > E-mail: maitken@xxxxxxxxxx > Text PAGE: page.maitken@xxxxxxxxxx > HTML PAGE: 4436774425@xxxxxxxxxx > www.newscentral.tv > www.sbgi.net > =================================== > > "If you listen to all the people saying > why you shouldn't, or can't, do something, > you'll never do anything." > > ------ Edward Whitacre Jr. -------- > =================================== > "Any sufficiently advanced technology > is indistinguishable from magic." > > ------- Arthur C. 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