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Interactive Beam Footprint Library Update 6/22/2015


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#101 ONLINE   HoTat2

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Posted 15 May 2014 - 10:33 PM

Don't most satellites have spare transponders they can bring up if they have a failure?

Yes, but spare transponders (at least usually) are not assigned specific frequencies among those listed in the FCC documentation. But are designed to be tuned to any of the transponder frequencies of the ones on the list they back up to take over for whichever of those when necessary.

 

i'm beginning to think that perhaps the discrepancy is simply that while there are a total of 80(81) possible transponders for the Ku band payload, only 72(73) of them are leased by Intelsat to DIRECTV LA ?

 

The problem is in the 12/12/13 investor day conference material, it list "80" transponders total as the actual count indicates.

 

Untitled.png

 

So I'm still not sure ....


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#102 OFFLINE   slice1900

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Posted 15 May 2014 - 11:06 PM

Maybe those Pan-regional 24 MHz transponders can be switched to 36 MHz operation, so rather than 16 24 MHz transponders they switch 4 off and run 12 at 36 MHz wide, and strategy was changed at some point along the way. Make that change for both H and V and you go from 80 operating transponders to 72.

 

D14 and D15's RDBS transponders work this way. They are all 36 MHz wide, but tpns 19 and 20 can be switched to 24 MHz operation to allow them to be used in the US, or they can use the full 36 MHz width if they're used only outside the US. The reason for that is that 17.7 to 17.8 GHz can't be used in the US, but can in Mexico/LA. Our RDBS bands are 400 MHz wide, theirs are 500 MHz.

 


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#103 ONLINE   HoTat2

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Posted 16 May 2014 - 11:12 AM

Maybe those Pan-regional 24 MHz transponders can be switched to 36 MHz operation, so rather than 16 24 MHz transponders they switch 4 off and run 12 at 36 MHz wide, and strategy was changed at some point along the way. Make that change for both H and V and you go from 80 operating transponders to 72.

 

Could be;

 

But I would think such a major feature of the satellite if it existed would receive some mention in at least the "Engineering Statement" submission.

   

... D14 and D15's RDBS transponders work this way. They are all 36 MHz wide, but tpns 19 and 20 can be switched to 24 MHz operation to allow them to be used in the US, or they can use the full 36 MHz width if they're used only outside the US. The reason for that is that 17.7 to 17.8 GHz can't be used in the US, but can in Mexico/LA. Our RDBS bands are 400 MHz wide, theirs are 500 MHz.

 

Are the RDBS transponders really going to work this way though?

 

As there's some confusion here since the original submission in 2006 for both the RB-1 RDBS payload to be used on board D14 titled "BSS-99W" to be positioned at long. 99.175W, and RB-2 titled "BSS-103W at 102.825W destined for D15?, includes Mexico and LA downlink beams in addition to the CONUS one, and therefore has this switchable transponder feature.

 

However the most recent submission for RB-1 and RB-2 in 2011 and now both titled the same way as "RB-1" and "RB-2" to be positioned at 99.235W and the same 102.825W respectively do not have Mex. and LA beams. Only a CONUS one.  


Edited by HoTat2, 16 May 2014 - 11:53 AM.

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#104 OFFLINE   slice1900

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Posted 16 May 2014 - 02:42 PM

The whole RB-1/RB-2 thing is too confusing to follow, I was just talking about the capabilities of the D14 and D15 satellites. Whether those capabilities are used after launch is a different matter.


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#105 ONLINE   HoTat2

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Posted 16 May 2014 - 03:12 PM

The whole RB-1/RB-2 thing is too confusing to follow, I was just talking about the capabilities of the D14 and D15 satellites. Whether those capabilities are used after launch is a different matter.

Yes I agree, confusing;

 

But to try and simplify anyhow, I'm just not sure the RDBS payloads to be used on D14 and 15 will have Mex. and LA beams. DIRECTV seems to have scrapped that idea for just a national beam covering CONUS, AL. HI. and the PR as indicated in the more recent 2011 filings for RB-1 and 2.


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#106 OFFLINE   slice1900

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Posted 16 May 2014 - 09:57 PM

Yes I agree, confusing;

 

But to try and simplify anyhow, I'm just not sure the RDBS payloads to be used on D14 and 15 will have Mex. and LA beams. DIRECTV seems to have scrapped that idea for just a national beam covering CONUS, AL. HI. and the PR as indicated in the more recent 2011 filings for RB-1 and 2.

 

The FCC filings don't show Mexico and LA only beams on frequencies not permitted in the US, do they? Transponders 19-24 may be aimed down south, but since 17.7 GHz - 17.8 GHz can't be used here there's no reason to show them in FCC filings.

 

The reason 95W Intelsat-30/31 beams are provided is because they're not just in Panamericana, they're in the US too, for people with the international dish.


SL5, PI-6S, SA-6AL, 3xSWM16; 21 H20-100, 1 H20-600, 7 H24-700/AM21


#107 ONLINE   HoTat2

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Posted 17 May 2014 - 07:03 AM

The FCC filings don't show Mexico and LA only beams on frequencies not permitted in the US, do they? Transponders 19-24 may be aimed down south, but since 17.7 GHz - 17.8 GHz can't be used here there's no reason to show them in FCC filings.

 

In the '06 filings for RB-1 and 2 originally titled as "BSS-99W" and "BSS-103W," the Schedule S documents list the CONUS+AL+HI+PR beam transponders as "AM1 - AM20" operated at 36 MHz except tps. AM19 and 20 which are operated in a 24 MHz mode.

 

The Mexico beam transponders are listed as "MX1 - MX24", all at 36 MHz.

 

And the Latin America beam tps. are listed as "LA1 - LA24," all at 36 MHz as well.

 

Attached File  BSS-99W Sched. S filed in 2006.pdf   73.62KB   28 downloads

 

Attached File  BSS-103W Sched. S filed in 2006.pdf   73.62KB   24 downloads

 

The '11 Schedule S filings however now titling them as "RB-1" and "RB-2" respectively list only a CONUS+AL+HI+PR beam with only 18 transponders, all at 36 MHz. No 24 MHz mode tps. 19 and 20 mentioned anywhere in the documents, nor are any Mexico or LA beam or tps. listed this time.

 

Attached File  RB-1 Sched. S filed 2011.pdf   57.21KB   32 downloads

 

Attached File  RB-2 Sched. S filed 2011.pdf   57.1KB   24 downloads

 

 

... The reason 95W Intelsat-30/31 beams are provided is because they're not just in Panamericana, they're in the US too, for people with the international dish.

 

 

Actually, as I posted in other threads, unlike G3C, there seems to be no provision for support of the 95W World Direct service on the new IS-30/31 birds. The only beam to be directed at N.A. is a spotbeam aimed at the southwestern U.S. to cover the Calif. Broadcast Center (CBC).

 

So either WD is to be still provided by G3C co-located with IS-30/31 for the remainder of its lifetime. Or WD service is to be moved to the main 99W-103W group, or the plan is for both these alternatives over time.    


Edited by HoTat2, 17 May 2014 - 07:24 AM.

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#108 OFFLINE   slice1900

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Posted 17 May 2014 - 01:25 PM

Well I have said for a while I expect that once D14 launches the content on 95W will be replicated on 99/103, so there will be no need for a second dish for new installs. But there will still be hundreds of thousands (millions?) of WD dishes out there, so they have to keep broadcasting it to the US until those would all be replaced. That may not happen until MPEG2 is retired, unless they want to migrate WD owners sooner. I would guess more of them are SD only subscribers than the national average, since if you watch a lot of WD content there's little point in paying Directv for HD service.

 

If G3C keeps broadcasting on the WD transponders, either the transponder frequencies or the footprint of those frequencies can't overlap. Unfortunately we don't seem to have G3C in the footprint library, so I can't tell if the transponders used for WD service are CONUS only. If they aren't, then the frequencies used for them can't be used by IS30 and IS31. Perhaps that accounts for the 72/80 transponder differential? 72 now, 80 at some future day when G3C is retired?


Edited by slice1900, 17 May 2014 - 01:25 PM.

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#109 OFFLINE   Gary Toma

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Posted 17 May 2014 - 09:14 PM

 

 

.....Unfortunately we don't seem to have G3C in the footprint library, so I can't tell if the transponders used for WD service are CONUS only.

 

Sorry, G3C was a June, 2002 launch.  We will be hard pressed to find any beam footprint data at all for this satellite.

:(




#110 OFFLINE   slice1900

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Posted 17 May 2014 - 10:09 PM

Sorry, G3C was a June, 2002 launch.  We will be hard pressed to find any beam footprint data at all for this satellite.

:(

 

Didn't mean that to sound like a criticism, I greatly appreciate the work you've done making these available with such a simple way to view them - well not so simple tonight since Google Earth keeps crashing on me! :bang

 

I did a little digging and found the beams at http://www.lyngsat.com/Galaxy-3C.html. If you look one of the Directv USA transponders and click on the "North American Ku" link, you visit http://www.lyngsat-m...America-Ku.html which shows the beams covering the US as well as Mexico. It is a bit weaker in Mexico, but pretty sure those same transponder frequencies couldn't be used by IS-30 or IS-31 unless they're hitting an EIRP of nearly 60.

 

IS-30/IS-31 are reported to have some spot beams, it might make sense to use the frequencies G3C does for some of the spots, then they could be beamed strongly enough and to locations where G3C's beam would be under the noise floor.

 

Gunter's space page says that they'll be co-located with G3C, which would seem to indicate G3C will stick around for a while. I found the original announcement for its launch, which stated it was planned for a 15 year life, so it should last until at least 2017. Given that Directv's older satellites look to be able to exceed their rated life, it may well last longer. So G3C should last long enough for Directv to migrate everyone off the WD dish, if not off MPEG2 entirely, before it has to be decommissioned.


Edited by slice1900, 17 May 2014 - 10:09 PM.

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#111 ONLINE   HoTat2

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Posted 18 May 2014 - 08:14 PM

 

 

... If G3C keeps broadcasting on the WD transponders, either the transponder frequencies or the footprint of those frequencies can't overlap. Unfortunately we don't seem to have G3C in the footprint library, so I can't tell if the transponders used for WD service are CONUS only. If they aren't, then the frequencies used for them can't be used by IS30 and IS31. Perhaps that accounts for the 72/80 transponder differential? 72 now, 80 at some future day when G3C is retired?

 


 

Sorry, G3C was a June, 2002 launch.  We will be hard pressed to find any beam footprint data at all for this satellite.

:(

 

Yeah...

 

Given G3C's early launch period before the FCC made the recent modifications to their filing system, we pretty much just have make to do with the various beam footprint illustrations listed in the G3C Technical data on file;

 

Thus, for the N.A. beam used by the WD service;

 

World Direct N.A.beam.png

 

And the transponder frequencies used by WD;

 

World Direct Transponder Frequencies .png

 

Note; the "green" colored outline are the range of available transponder frequencies used by WD, and the "Red" outline are the transponders being used at present for the service as indicated by the Network Decoder given in Gary's the latest TPN maps.

 

So while there will be a frequency overlap with the WD tps. and the upper set of transponders used by the regional beams of IS-30/31, there is of course no geographical overlap since the regional beams will all be far to the south covering S.A. 


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#112 ONLINE   HoTat2

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Posted 19 May 2014 - 04:19 AM

Also;

 

Here's a convenient illustration of the transponder numbering used by World Direct service as they appear on the DIRECTV receiver signal level screen and Network Decoder in the TPN maps.

 

As you can see any active tp. numbers for WD service correspond only with one the sixteen 27 MHz bandwidth tps. Never the larger 54 Mhz ones. The numbers with the green circles are the currently active tps. for WD service.

 

WD Transponder Numbering.png

 

 

 

 


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#113 OFFLINE   P Smith

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Posted 19 May 2014 - 09:50 AM

well, there is no one type of a sat tuner [chip] in consumer's receivers/DVRs has specs to utilize 54 MHz transponder, so far 36 MHz is the max bandwidth ... perhaps set by profitable level

#114 OFFLINE   slice1900

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Posted 19 May 2014 - 11:26 AM

well, there is no one type of a sat tuner [chip] in consumer's receivers/DVRs has specs to utilize 54 MHz transponder, so far 36 MHz is the max bandwidth ... perhaps set by profitable level

 

So what are those 54 MHz tpns used for? Is it internal use like the 250 and 500 MHz wide tpns on Directv's 101/ka?


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#115 OFFLINE   P Smith

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Posted 19 May 2014 - 12:15 PM

I guess so , need different equipment to receive wider bandwidth/high bit rate (> 45000 KSPS), perhaps special communication terminals made by DTV for the purpose



#116 ONLINE   HoTat2

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Posted 19 May 2014 - 12:44 PM

well, there is no one type of a sat tuner [chip] in consumer's receivers/DVRs has specs to utilize 54 MHz transponder, so far 36 MHz is the max bandwidth ... perhaps set by profitable level

But is it really necessary for an IRD tuner to match the total *physical* bandwidth of a transponder P. Smith, or just the *occupied* bandwidth a signal's spectrum is effectively using when being relayed through a transponder?

 

For instance, I think this is what causes the confusion with the 62.5 MHz tp. bandwidth specification of the Spaceways in their documentation. While the total physical BW may be 62.5 MHz, the spectrum of the transmission occupies is only ~36 MHz of it.

 

And of course the occupied BW of a spectrum is what actually shows up on a spectrum analyzer, not the phy. BW of the satellite transponder.

 

In fact, from the frequencies and symbol rates quoted for G3C by you P Smith on LyngSat, Puerto Rico subscribers must have formally received their HD programming via three of those 54 MHz tps. in the earlier diagram I posted (tps. 2, 5, and 11) as part of "Beam PR."

 

That is to say it must have been at the time, a 36 MHz wide spectrum transmission (or the "occupied bandwidth") sent within a 54 MHz wide satellite transponder (it's physical bandwidth).

 

Though I admit the only discrepancy to this issue which I was never able to resolve was the downlink linear polarization stated for these 54 MHz tps. given in the FCC documentation, when circular polarization would have been required for PR subs. as is listed by you on LyngSat. as "LHCP." for those tps.       


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#117 OFFLINE   P Smith

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Posted 19 May 2014 - 02:03 PM

no, you got it not correctly, there is no "occupancy"

Ka tpns of SW-1/2 (with capabilies to use 62.5 MHz and wider) transmitting signals in 36 MHz bandwidth, that physical , that's what we saw on spectrum analyzers

it could be done by using a bandpass filter at sat,or uplink center (I'm not sure where it is done), but the tpns does not transmitting any signal out of 36 MHz

while center of each tpn spacing at 61.5MHz  figure


Edited by P Smith, 19 May 2014 - 02:04 PM.


#118 ONLINE   HoTat2

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Posted 23 May 2014 - 11:13 AM

no, you got it not correctly, there is no "occupancy"

Ka tpns of SW-1/2 (with capabilies to use 62.5 MHz and wider) transmitting signals in 36 MHz bandwidth, that physical , that's what we saw on spectrum analyzers

it could be done by using a bandpass filter at sat,or uplink center (I'm not sure where it is done), but the tpns does not transmitting any signal out of 36 MHz

while center of each tpn spacing at 61.5MHz  figure

Well  P. Smith ...

 

Maybe my terminology of "available" vs "occupied" transponder bandwidth wasn't the best choice, but it still seems like we are talking about the same thing here.

 

If the total "available" bandwidth of a tp. like on the Spaceways when operated in their "non-processor" or "Bent-Pipe" mode is 62.5 Mhz, but only 36 Mhz of that is used by the spectrum of a 36M0G7W type transmission relayed by it. Then about 26.5 MHz (+/- 13.25 MHz on either edge for a frequency centered signal) of the transponder's available bandwidth is not being used.

 

Or is "unoccupied."

 

And a signal with a 36 MHz wide spectra centered on the tp. center frequency is what should register on a spectrum analyzer.      


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#119 OFFLINE   P Smith

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Posted 23 May 2014 - 03:46 PM

good, that was my point - no signals out of 36 MHz range on each Ka tpn, regardless its design and FCC description

#120 OFFLINE   slice1900

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Posted 23 May 2014 - 08:19 PM

P Smith,

 

When you say you saw 36 MHz wide tpns from SW1/SW2 on a spectrum analyzer, were they using 36 MHz of a 62.5 MHz slot like HoTat2 suggests, or were they spaced the same as other Ka tpns? According to the FCC filings, the 8 62.5 MHz tpns in the Spaceway sats are contiguous, which sounds to me like they could create the same output as Directv's normal Ka sats.

 

The Ka mapping has a 12 MHz guard band at the start of a 500 MHz block, then a 36 Mhz tpn, then a 4 MHz guard, then a 36 MHz tpn, and so on with another 12 MHz guard at the end of a 500 MHz block. So SW1's first 62.5 MHz tpn could have data from 12-48 MHz and 52-62.5 MHz, and the next tpn has data from 0 to 25.5 MHz and 29.5-62.5 MHz, the next from 0-3 MHz, 7-43 MHz and 47-62.5 MHz, and so on...

 

But it doesn't appear to work this way, despite the FCC filing suggesting it might, because if you look at the TPN map, you see 103 has 4 Ka hi tpns from SW1 and 16 Ka hi CONUS tpns from D12. That's kind of what I'd expect if those 4 SW1 tpns (2 per polarity) were using only 36 MHz of the 62.5 MHz available. This would take up the first eight (4 per polarity) slots when using the normal Ka mapping. Otherwise, there would be room for 4 more spots from SW1 or 4 more CONUS tpns from D12.

 

If the Spaceway sats are being "wasteful" with spectrum by using only 36 MHz out of 62.5 MHz, I wonder if D14 will take over SW2's spots and SW2 be relegated to spare or internal-only duty? Otherwise the six SW2 spots shown will leave only 14 Ka hi CONUS tpn slots available for D14 to use.


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#121 OFFLINE   P Smith

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Posted 23 May 2014 - 10:30 PM

that's outcome of SW-1/2 co-location with D110/11/12 ... check with Gary the middle freqs of 6 tpns at SW-1/2



#122 ONLINE   HoTat2

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Posted 25 May 2014 - 04:23 AM

that's outcome of SW-1/2 co-location with D110/11/12 ... check with Gary the middle freqs of 6 tpns at SW-1/2

According to the Schedule S documents for the Spaceways, the tp. center frequencies for "Bent Pipe" mode are simply at multiples of 62.5 MHz, with half this bandwidth or 31.25 MHz on the upper and lower band edges.  
 
19731.25 MHz
19793.75 MHz
19856.25 MHz 
19918.75 MHz
19981.25 MHz
20043.75 MHz
20106.25 MHz
20168.75 MHz
 
Tps. 1 - 6 marked in red (two tps. per freq.).
 
Which the above must mean that in order to use all 6 transponders aboard SW1, either tp. pair 9/10 (centered at 19890 MHz) on D12 can't be used due to overlap or tp. pair 5/6 on SW1 is offset from it's center to somewhere toward the lower edge of its assigned band.
 
But I think it's more likely only tps. 1-4 on SW1 (or the first two frequencies in red) can be used as at present with tp pair 9/10 of D12 active.   

Edited by HoTat2, 25 May 2014 - 04:36 AM.

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#123 OFFLINE   slice1900

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Posted 25 May 2014 - 05:36 AM

The center frequencies for the physical transponder don't matter, it is the center frequency of the 36 MHz wide signals they're broadcasting today that matter. Do they have a 36 MHz wide signal centered on those frequencies, or are they using several of those 62.5 MHz tpns to broadcast a larger number of 36 MHz wide signals centered along the usual Ka plan? I think we'd need a spectrum analyzer's output to answer that.

 

I believe the schedule S just describes the hardware and what it is capable of. If they need to file amendments as the use of that hardware changes, there should be an amended schedule S filing that describes 36 MHz wide signals somewhere. If they don't mention that anywhere, I think it is just telling us what the hardware can do, which we already know, not telling us how it is being used today.


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#124 ONLINE   HoTat2

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Posted 25 May 2014 - 04:47 PM

The center frequencies for the physical transponder don't matter, it is the center frequency of the 36 MHz wide signals they're broadcasting today that matter. Do they have a 36 MHz wide signal centered on those frequencies, or are they using several of those 62.5 MHz tpns to broadcast a larger number of 36 MHz wide signals centered along the usual Ka plan? I think we'd need a spectrum analyzer's output to answer that.

 

I believe the schedule S just describes the hardware and what it is capable of. If they need to file amendments as the use of that hardware changes, there should be an amended schedule S filing that describes 36 MHz wide signals somewhere. If they don't mention that anywhere, I think it is just telling us what the hardware can do, which we already know, not telling us how it is being used today.

But what is hard to understand there is unless they are treated as physically distinct 62.5 MHz wide transponders, how can they be individually assigned to distinct spotbeams for up/and downlink?

 

That is to say, how can a 36 MHz wide 36M0G7W transmission straddling one of the 62.5 MHz demarcations in your prior example be assigned to an actual spotbeam? 


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#125 OFFLINE   slice1900

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Posted 25 May 2014 - 08:50 PM

But what is hard to understand there is unless they are treated as physically distinct 62.5 MHz wide transponders, how can they be individually assigned to distinct spotbeams for up/and downlink?

 

That is to say, how can a 36 MHz wide 36M0G7W transmission straddling one of the 62.5 MHz demarcations in your prior example be assigned to an actual spotbeam? 

 

Ah yes, that is a big problem isn't it! So I guess it must be wasting spectrum and using only 36 MHz out of each 62.5 MHz transponder.

 

Which is why I wondered about this, since it would seem to make sense for Directv to take SW2 off spotbeam duty once D14 is fully operational. Otherwise they'll effectively be wasting 1/6 of their Ka hi bandwidth from 99.


SL5, PI-6S, SA-6AL, 3xSWM16; 21 H20-100, 1 H20-600, 7 H24-700/AM21





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