John; These reserved bits are new to me (I tend to avoid anything out of the packet layer), but I think that the document anticipates enhancement layers, and so the upshot is that I still don't see FCC approval being necessary. I don't even see it as being a matter of wiggle room. Also, the ATSC petitioned the FCC to incorporate by reference the next-to-most recent version of A53; the FCC on it's own motion, a year ago December 31, adopted A53:2007 by reference. There is no later version at this point. In that document, the FCC strongly hinted that it would defer to the ATSC on all emission matters, aside from mandating video format sizes. While it wouldn't 'take much' for the FCC to incorporate A/153 by reference, merely asking the FCC to do so would take a minimum of about 7 months. That would -- as your initial post alluded to -- seriously impact early adoption of M/H, since it could not even begin until the standard was published. That should occur by mid-summer. It's above my pay grade to determine if the ATSC will subsequently request FCC action on A/153, but I tend to doubt it. Without any clear need for FCC approval, some people will be able to see M/H devices under their Christmas tree, or as Channukah gifts this year. By the way, my analysis cannot be extended to Mexico or Canada. Each has different laws, policies and procedures. Indeed, from by understanding of COFETEL (Mexico's RF regulator, part of the Secretariat of Communications and Transportation), explicit authority would be required there. John Willkie -----Mensaje original----- De: opendtv-bounce@xxxxxxxxxxxxx [mailto:opendtv-bounce@xxxxxxxxxxxxx] En nombre de John Shutt Enviado el: Thursday, January 15, 2009 2:20 PM Para: OpenDTV Asunto: [opendtv] Re: Sixty-three TV stations to launch mobile DTV service this year John, Please see embedded replies: ----- Original Message ----- From: "John Willkie" <johnwillkie@xxxxxxxxxxxxx> > Indeed, I think that stuff -- to the extent I understand it -- is quite > elegant. Absolutely. I agree. M/H seems to be very well thought out and elegant in it's minimal disruption of existing data structures. > I'd be interested in you pointing me to reserved fields in A/53:2007 and > A/65c that you believe now will be unreserved as a result of CS/153 being > adopted. I did state "Data Field Sync." I have by no means done an exhaustive examination of A/153, but while trying to get through the document I found this: "5.3.2.13.1 Data Field Sync The diagram of the Data Field Sync in A/53 Part 2:2007 is repeated here for convenience of the reader as the reserved area is redefined in the immediately following sections (see Figure 5.32)." The item that caught my eye was the phrase "the reserved area is redefined in the immediately following sections". This would appear to be in conflict with A/53:2007 which states: "6.5.2.4 Reserved "In the 8-VSB mode, 92 symbols of the last 104 symbols shall be reserved, and they shall be followed by the 12 symbols defined below. To maintain a longer period with a flat spectrum, it is recommended that these 92 symbols be filled with a continuation of the PN63 sequence when only 8-VSB is present. "When one or more enhanced data transmission methods are used, the previously reserved symbols (including the 12 precode symbols used for 8-VSB and E8-VSB) shall be numbered from 1 to 104, in the order transmitted. The 12 precode symbols shall be preceded by 10 symbols that shall be used to signal the presence of an enhancement or enhancements, as defined below. The use of some or all of the remaining 82 symbols shall be defined by each enhancement." There may be 'wiggle room' in A/53:2007 to allow a different loading of those reserved Data Field Sync bytes. Again, I don't know. As far as A/65C goes, a closer examination has revealed that I was mistaken about any reserved PSIP fields being used. I misunderstood the explanation of handling legacy PSIP compatibly during my first cursory reading of the candidate standard, so I apologize. As I understand it, a separate M/H 'service guide' is included in the M/H data stream. And there is still the E8-VSB use of null packet PIDs to hide their enhanced payload data from legacy receivers. Not that there is a single E8-VSB receiver available to the consumer, but M/H does appear to use a different data scheme after the null packet PID that is different than that defined in A/53:2007. I am just trying to understand what the FCC might interpret as allowable under their adopted rules vs. what clearly is a well thought out M/H scheme that is compatible with legacy receivers. It wouldn't take much for the FCC to adopt A/153 by reference, and indeed to adopt the latest version of A/53 at the same time. I believe at one point there was inquiry made by the FCC for comments to have them automatically adopt any ATSC standards as FCC rules. I don't think that went anywhere. 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