[opendtv] Re: 20050509 Mark's Monday Memo

  • From: Craig Birkmaier <craig@xxxxxxxxx>
  • To: opendtv@xxxxxxxxxxxxx
  • Date: Thu, 26 May 2005 08:31:45 -0400

At 3:38 PM -0400 5/23/05, Manfredi, Albert E wrote:
>Yes, there might be times where a simulcast makes
>sense, but hopefully not at the expense of the main
>signal. For example, service to mobile handheld devices
>to cover the entire market area might be quite
>inefficient if the normal DTT transmitter(s) are used,
>but might be better handled by a cell service.

Your response shows your bias in terms of the way the DTV 
infrastructure should be operated.

In my example, the content provider is paying fees for carriage of 
specific services. I am assuming that a spectrum utility is operating 
that infrastructure, and that they can segment the services in 
whatever way makes the most sense on an instantaneous basis, just as 
DirecTV and Echostar do today. With these services you do not tune to 
a specific satellite and transponder for HGTV; that channel may move 
from one transponder to another based on the desires of the operator 
- virtual channel tables are used to direct a receiver to HGTV, 
wherever it is currently being mapped to the system.

The need to cripple an HDTV service to make room for other channels 
in a multiplex is a uniquely tied to the current way in which 
broadcast channels are assigned and operated by the government. Each 
6 MHz channel is a unique service, operated by the licensee. The 
licensee must decide how to allocate their bits between services 
including the possible use of hierarchical modulation for different 
classes of service.

On the other hand, with a spectrum utility, all of the 6 MHz channels 
assigned to a market would be operated by a single entity. They would 
have the freedom to allocate those channels in any way they need to 
on an instantaneous basis. If a content provider bids for carriage of 
a service at say 12 Mbps using modulation appropriate for fixed 
receivers, that is what the utility would be contractually obligated 
to provide. Ditto for any other service. The utility would decide 
where to map that content and how to best utilize all of the channels 
in the service to meet the demands of "the marketplace."

It is quite possible that the utility would NOT use hierarchical 
modulation at all, choosing instead to operate some channels in 
robust mode and others in high bit rate modes.  This could be a 
benefit to portable/mobile receivers, as there might be 10-20 robust 
services in a single channel all accessible via only one tuner.

Bottom line, being able to manage 60-100 MHz of bandwidth in a market 
dynamically, as opposed to 10 or more operators each of whom has only 
6 MHz to manage changes the game entirely.

The alternative that you suggest - i.e. segmentation of spectrum into 
different competing services - would likely result in less efficient 
use of the spectrum and higher costs to content providers and 
consumers. Even more important, however, it is likely that the 
consumer would need different appliances to use each service.

>It might make more sense for broadcasters to give
>Verizon retransmission consent on Vcast than to try to
>try to use either DVB-H or E-VSB, for these handhelds.

Who is talking about handhelds? Only the phone guys.

There will also be portable TVs, notebook computers, 
receivers/displays in vehicles (for passengers), etc. More important, 
however, the phone companies like to charge for bits; they will want 
to charge a per minute fee for everything you watch, because they 
paid a huge fee to buy the rights to use the spectrum.

>>  Why is our policy based on the idea that this
>>  capacity belongs to the broadcaster?
>Only for OTA TV and radio transmission. For cable, DBS,
>and satellite radio, the capacity belongs to another
>gatekeeper -- the service provider.

Different gatekeepers, same problem. When you allocate spectrum to an 
operator, rather than a service, the operators will use their 
gatekeeper abilities to control the market. On the other hand, if you 
allocate spectrum to a service, and create a marketplace to determine 
the instantaneous cost of buying access to that service, you 
eliminate much of the inefficiency and gerrymandering that occurs 
with our current system.

>Is there a problem with supporting both models?

None at all. The technology now exists to make the allocation of 
spectrum to monolithic gatekeeper services a relic of the past. Bits 
are bits, and one well designed digital broadcast infrastructure can 
deliver any and all services with dynamic re-allocation of resources 
driven by real marketplace demands.

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