Separate names with a comma.
Discussion in 'DIRECTV General Discussion' started by Curtis0620, Aug 25, 2008.
So what does all of that mean in english?
My take is that there appear to be several patents on DVB-S2 technology and the licensing is being combined so that they are all covered.
It means they've taken a bunch of related technologies from several companies and bundled them into an easy to "eat" license ("Happy Meal"). They are hoping others that now know the licenses are available and at what the costs are will adopt the technology and pay the fees. Without offers like this its risky for a company to adopt a given technology without first entering extensive license negotiations with multiple companies.
The companies that created this initiative have figured out some split of the license fees.
It also tends to serve as notice to those that may be using the technology without a license that DTV holds those patents and what they would claim as damages.
DVB-S2 is something you don't hear much about in this forum, and I applaud DirecTV for taking the leap and adopting it (the "other" company isn't using it). The article mentioned a 30% performance improvement over DVB-S, and this is true. What it means to us is more HD channels and less rain fade at Ka band. DVB-S2 allows MPEG-4 compression for HD and pilots to recover the signal during high noise conditions (rain fade).
So far DirecTV is using DVB-S2 for some of the locals. The problem with DVB-S2 is it's not compatible with the older DVB-S receivers, so they have to replace all of the older receivers before they can implement DVB-S2 across the board. This is the main reason Dish has so far chosen to not use DVB-S2.
But why would Dish not use it on their newest MPEG-4 receivers? Their HD is or soon will be exclusively MPEG-4, and their Eastern Arc service is MPEG-4 only, so that would seem to be the perfect time to go with it.
I had moments of rain rade on both SD and HD local channel feeds last night during the Olympic volleyball and closing ceremony, storms in the metro Atlanta area had me reverting to OTA at times.
Don't know. When I was at the NAB show in April I walked over to the Echostar booth and asked if Dish had any plans to implement DVB-S2. The person I spoke to said no, because it was too expensive to change out the existing receivers.
The pilots used with DVB-S2 can not eliminate rain fade, only help. Ka-Band is more susceptible to rain fade than Ku-Band, so the DVB-S2 pilots help keep Ka-Band on par with Ku. But they can't eliminate it completely.
As this is a press release, we can quote the whole release
Well said and described.
You say that like its a bad thing.......OTA-HD, unless taken directly from the station via fiber which they are not doing at very many places, will be better than DirecTV if received by a good antenna. I am not trying to starting a debate, just stating something that as a local TV engineer makes me upset.
It's not a bad thing, just a convenience thing.
No, not bad at all. Reverting was a bad choice of words.
I usually watch the OTA feeds especially whenever I am merely watching live tv. During the Olympics I was using the MPEG-4 feed from DirecTV a lot because I was doing so much recording of stuff.
Scott and/or others,
What are pilots in this context?
Pilots, or more correctly pilot symbols, consist of additional information which the receiver uses to help lock onto the carrier. That's a very simplified description.
The pilots are inserted into the DVB-S2 frame structure along with the data (video and audio information).
DVB-S2 allows the use of higher order modulation compared to DVB-S which allowed only QPSK. These higher order modulations (8PSK, 16APSK and 32APSK) require LNBs with high stability and low phase noise. In short, DVB-S2 can not get away with the cheaper LNBs now used by DVB-S. These pilot symbols give the receiver something to lock onto.
Another example is during rain fade when the C/N drops (signal falls into the noise). The pilots help the receiver hang in there a bit longer before losing lock.
Possibly forward error correction?
No, nothing to do with FEC. Just to do with helping the demod lock. 73, K7KQ
This is almost painful reading, but it does describe pilots...
This is most likely marketing politics. The phrase "offered at reasonable and non-discriminatory terms" is generally necessary for private intellectual property to become part of an ITU Recommendation. DVB-S2 is now an ETSI (The European Telecommunications Standards Institute) standard. By making it an ITU Recommentation, the owners of the DVB-S2 intellectual property will make more money in the end.
D* is already using DVB-S2 for MPEG4 HD, except they use QPSK because KA band has much lower noise threshold than KU. E* can switch to DVB-S2 at any time. Their video coding is exactly like DVB-S2, but they use 8PSK with FEC Turbo Coding which gives them 10% bandwith gain over FEC Trellis coding used with DVB-S2.
So E* is using 8PSK on the MPEG-4 offerings via Ku, whereas D* is using QPSK on their Ka channels?
This maybe explains how E* is able to squeeze all their SD and HD programming onto the new MPEG-4 only Eastern Arc constallation of satellites?