Bev Testing MPEG4

  • Thread starter Thread starter SensualPoet
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I never mentioned anything about FEC. But if you are curious, if they do go to 8PSK it will be 2/3 FEC at 21500 SR. No need to explain uplink standards and other variables to me ;)
 
And I'm sure BEV will offer you a similar deal to stay. No big deal, they all do that. BTW, going from BEV to Shaw is a downgrade, in terms of HD and PVR.

-Mike
 
If you read Scot's post , there will be new HD channels coming out .I 'm so excited because I have been waiting for new HD receivers since I wanted to have HD but did not want to spend money buying on old MPEG-2 models.
 
CH. 888 206-4 12545 20000 V 5/6 MPEG4 720i Colour Bars

Note how they have now moved from 480i to 720i??
Hey that's what the analyzer says 720i.

Maybe that's their version of the evil HD-Lite!
 
You're out of reality, sorry.
Bev follow Dish in each move - so, forget DVB-S2 and expect 8PSK with TC and H.264.
 
To the best of my knowledge, the ATSC specifications for HiDef DOES NOT include 720i.

Apparently DN A&E HD was showing 720i as well.
I think we need to get some new friends with a different/new HD FTA unit and validate these 720i observations.
It may be some tricks and could easily fool many subs or it might be a chip or s/w anomalie of these new MPEG4 chipped boxes.

But since there seems to be legit 720p and 1080i signals in both MPEG2 & MPEG4 formats, then these signals are somehow being registered as 'different' for good or bad.
 
Possibly, do you have a DCT641x?
I'm have 6 PVR's, 3 are HD.

Aside from a crappy UI on the DCT, it WORKS and WORKS WELL.
At least for me, but then I know what I'm doing too.
 
Probably as they are still under the false belief that they are still Canada's leader in HD, just as they didn't know their anti-piracy efforts, as trivial as they are, had a greater effect on paying subs than actual pirates.

It'll sure be funny when the day comes and a meeting is called and they are all told to go home.

It's a sad day for the rank and file when that happens, but for the suits, there is absolutely NO excuse.

BTW, I've been called to those types of meetings, as a pawn of course, way back then.
 
How I mean to come across is that for two identical streams with identical encoding, and error correction and symbol rate, A change from QPSK to 8 PSK will give an extra 50% (I made a typo in my orginal post, 8 PSK is 3 bits/symbol, not 4) in bit rate but typically requires more power margin.

It's not as simple and straight forward as some might think. Sure they may be able to switch to 8 PSK, but they likely would be required to use a less aggressive FEC in order to maintain the same signal margins, thus reducing some of the gains in bit rate that they would see from migrating to 8 PSK.
 
Swapping out the 6000's and switching to 8PSK after Nimiq 4 launches certainly seems like the logical next move.

-Mike
 
To report that, you must be an insider.
If what you say is true, then I suspect the encoder must be mis-configured or your are diddling with the MPEG2/4 flags as already discussed.

If it is not true, than to disavow knowledge of actual MPEG4 testing would be consistent as almost everything reported here, Bev denies as false and often later turns up as just the opposite.

We understand the reasons for doing so as corporate policy is to tightly control the knowledge to the public so it best serves your interests.
Even if its done deceitfully.

History already proves me correct.
 
To get back on topic a bit, yes 8PSK provides a 50% increase in bit rate for a given symbol rate (BPSK = 1 bit per symbol, QPSK = 2 bits, 8PSK = 4 bits, etc). However, higher order modulation typically requires a higher carrier to noise per bit (C/No) threshold. So all other things considered equal, If the Nimiqs are operating at or near maximum power (which it is likely they are, due to their questionable health and age), they may not be able to increase power enough to maintain service availability numbers and take full advantage of 8PSK.
 
i must admit, i was a little disappointed in the lack of "HD" programming, on the HD channels when i first got my 9200 a year or so ago
hopefully, more HD programming will come with the addition of more HD channels, as i hate changing the aspect ratio, everytime a fake "HD" program comes on
some cheese with my wine...
it cant be a bad thing, adding more HD, but im not getting excited yet, as they are already late in releasing the stb's (late spring/early summer)
 
I don't think thats really a concern, if you like football, chances are you can find most of the games up there with a (unhacked) Free To Air Receiver.
 
MPEG2/4 are standards for encoding video and associated data into a bit stream. They are fairly indpendent of the modulation and forward error correction used as well as the power required. Different encoding schemes offer more efficient compressions methods than others. Higher compressions rates are typically less tolerant of bit errors/loss than becasue mroe information is packed into each bit. The end product is basically just a bit stream.

Modulation techniues on the other hand is how this bit stream is converted into an electrical signal. The capacity of a transponder is given in MHz. The transponder capacity in MHz = the Mega symbols per second capacity for that transponder. (i.e. a 24 MHz transponder has a capacity of 24 Msps). The bite rate capacity is then determined by modulation type. (BPSK = 1 bit/symbol, QPSK =2, 8 PSK = 3, 16 PSK/QAM = 4, 256 QAM = 5) Therefore the bit rate capacity of a transponder modulated at BPSK is 24 Mbit/s, QPSK = 48, 8PSK = 72 Mbit/s.

This is purely the total bit rate. Now you have to take into account and forward error correction (FEC) being used. The same 8 PSK carrier with an FEC rate of 1/2 applied reduces the bit rate of the data stream down to 36 Mbit/s. Rate 3/4 takes it to 54, rate 7/8 takes it to 63. The actual number of bits being transmitted is still 72, but the FEC adds overhead reducing the bit rate of the payload)

Why would they use FEC if it reduces the bit rate? Becasue each modulation type has a required signal level in order to ensure that the receiver can accurately differentiate one symbol from another. Single threshold are given to maintain a specific bit error rate, typically 1x10e-09, or one bit error per billion bits. As you go below that threshold, the bit error rate increases. what FEC does, is provides the receiver enough information to check the data stream for bit errors, and correct them without requiring the sender to retransmit them. FEC results in what is referred to as coding gain allowing you to send more payload bits for a given power level. Satellites are very limited in how much power is available to them via their solar panels and how much power they are allowed to transmit according to the regulatory agencies.

So while FEC isn't 100% efficient use of the available spectrum, it is basically what allows you to use a 18" dish instead of a 5 foot dish.

To summarize, MPEG defines how video is represented as a bit stream, QPSK and 8 PSK are modulation types that determine how many bits per second a satellite can handle.

I've simplifed things a fair bit, but this might provide a few people with a few bits of technical information.
 
I would highly doubt that BEV wouldn't let people who own their equipment keep what they own if they bought new receivers, discounted or not.

I heard quite a bit of grumbling from *C subscribers in my area... many of them had bought used equipment, or had been *C subs for years, and now had to buy new equipment again just to get the SAME programming. That's what I think the killer was - this wasn't upgraded or optional, this was the same.
 
BEV never released any official information when they are coming with MPEG4 receivers.It was announced on this site , the information was false that is why BEV stopped advertising here.Now everybody blames bell for not releasing any news about HD and new receivers. It could happen in 2 years ,who knows,I guess when BEV is ready we will hear about it.
 
Any new info on when Bev will switch to MPEG 4?

I contemplating buying a 9200 for the HD...As I know it is only MPEG2 capable.

2009 sound right? 2010?

Cheers!
 
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