Moved to the same transponder/DL freq on Gal 12 which replaced Gal 15 about a month ago.
G15 troubles
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It's not possible to move a sat to the north or south edge of it's box.
It _IS_ possible to put it into an inclined orbit so it moves to the north and then to the south once each day. I think that I suggested this as a possibility many messages ago. This COULD possibly keep the sats separated a bit if they time the inclination so that when G15 was north, AMC-11 would be south, and visa-versa, and they'd only be close when crossing from north to south, and even that might not be real close, as inclined sats generally also drift east and west during a day's orbit, so they might be able to time that as well.
However right now, G15's inclination is only about 0.135 degrees, so they might be able to keep them separated by a few tenths of a degree. That may be enough for uplinks with BIG dishes, but I'm not sure.
Relative to the "G 15 has the opposite polarity configuration of AMC-11. This should minimise the interference" thing, yes, they are opposite polarity, however that doesn't help much with respect to minimizing interferrence. Basically both sats will be repeating signals on all frequencies except narrow bands between the various transponders. Ie for example, AMC-11 is vertical on odd transponders, and G15 is horizontal on odd transponders, but G15 will retransmit everything except in a narrow, perhaps 4 MHz band right at the boundaries, like on AMC11 4080 and 4120 are V, but those freqs are H on G15, however on G15, the 4100 vertical transponder will cover everywhere from about 4082 to 4118, and will retransmit the 4092 signal completely, and will retransmit the sidebands of the 4120 signal. Also, the 4160V transponder will retransmit most of the 4075V signal. Ie the opposite polarities may help minimize interferrence for signals that are exactly in the middle of their transponders, like the 4120 signal, but it won't help at all for most narrow band signals like the 4092 signal.
Since AMC11 is mostly populated by wide band signals centered on the respective transponders, it is probably won't be quite as bad for those as it would be for randomly positioned narrow band signals. There are probably dozens of narrow band signals on the sat that aren't video channels listed in Lyngsat, and they WILL be affected, and those channels are also probably uplinked from facilities that don't have huge dishes able to have sufficient resolution to avoid hitting G15.
Anyway, this will be very interesting. I just wish the trees had taken a bit longer to start leafing out so that I could watch.
This is getting major news attention here, I've had probably 4 or 5 people ask me about the so-called "Zombie Satellite" and what's going on with it. It's kinda cool to see people get excited or even just a little interested in how satellites work.
of course local tv news is in sweeps and doing "How a ZOMBIE SATELLITE could interrupt YOUR favorite show's season finale... news at 11!"
of course local tv news is in sweeps and doing "How a ZOMBIE SATELLITE could interrupt YOUR favorite show's season finale... news at 11!"
[ame="http://www.youtube.com/watch?v=JYfM-frIWlQ&feature=related"]YouTube - Lost in space robot DANGER WILL[/ame]"Lost" in Space???
For anyone who wants to see a 3D view of where G15 or any other satellite is in relation to your location. Just click the link below:
NASA - Science@NASA J-Track 3D
NASA - Science@NASA J-Track 3D
Yes...Nut Alert! ABC's feeds are much further east than AMC-11. There should be no interruption.
Yes...Nut Alert! ABC's feeds are much further east than AMC-11. There should be no interruption.
The cost of all the commercials during the Lost Series Finale is easily enough to buy an entire satellite...
(... in other words, if ABC happened to be on AMC-11, they would be renting space elsewhere right now in time for May 23rd...)
Does anyone understand the SES plan? I'm trying to figure out why they are going to all that extent when home dish owners and probably most cable companies only use 10 foot downlinks and thus can't pick off a particular satellite within a few degrees of each other.
Is phasing a problem with AMC-11 and G15 close together or would it be no problem to have transmissions come down from each one together that is within the beamwidth of a 10 foot dish?
Even a simulsat used at some cable headends only has the performance of a 10' or so prime focus dish, right? If so, I don't think it would pick off AMC-11/G15 or SES-1 individually so I don't see what the big deal about the plan is unless you have a large enough dish to be able to pick off satellites individually rather than a 10' dish that can see all three in the same beamwidth.
Is phasing a problem with AMC-11 and G15 close together or would it be no problem to have transmissions come down from each one together that is within the beamwidth of a 10 foot dish?
Even a simulsat used at some cable headends only has the performance of a 10' or so prime focus dish, right? If so, I don't think it would pick off AMC-11/G15 or SES-1 individually so I don't see what the big deal about the plan is unless you have a large enough dish to be able to pick off satellites individually rather than a 10' dish that can see all three in the same beamwidth.
SES-1 may have significantly higher power capabilities.
Also, a 10 foot dish can be detuned enough to separate satellites with some separation.
Also, a 10 foot dish can be detuned enough to separate satellites with some separation.
Most cable companies use 14 foot or bigger dishes, the beamwidth is tight on them. From What I'm hearing the reversed polarity of G-15 is suppose to really play havoc. Even with maneuvers it may not be enough for isolation. Many cable networks are on that bird and there expecting the worse. Since this has never happened before, no one really knows what to really expect. We will have to see how it plays out.
Gizmodo's Post on the Zombie Sat
I like how the media is starting to use the Zombie description of G15.
The Attack of the Zombie Satellite - Galaxy 15 - Gizmodo
I like how the media is starting to use the Zombie description of G15.
The Attack of the Zombie Satellite - Galaxy 15 - Gizmodo
Re the plan, I think that it's the uplink that's important, not the receiving stations. Ie, if they have a very big dish uplinking, that can only hit AMC11, then it doesn't matter what size dish the receiving stations have, because G15 won't be transmitting much.
Re the phasing, I think that's 90% of the issue. Since the 2 sats are at different distances that are always changing, phasing will be all messed up. I think the other issue is that on high SR signals, I would think that the signal from G15 would be terribly distorted since the center of the transponder will be missing due to the reversed polarity.
Anyway, I think using a big uplink dish capable of hitting only one sat is the best bet, but I'm sure there will be times when they can't do that. In those cases I still think turning off some of the AMC11 transponders and just letting G15 do the work might be the best answer, but I think it would only work well on narrow signals.
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