Bandwidth of satellite transponders

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Superkomanda
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Hello there! :)
So I was talking with the friend today and he asked me, what's the bandwidth of transponders (I mean in "mbps")? And, I couldn't answer properly, so I would like to know.
As I know, there are 24 mbps on DVB-S. And there's no difference, if signal is in MPEG2 or MPEG4, bandwidth will be the same on transponder?
The next thing is DVB-S2. What's the bandwidth there? Thanks again! :)
 

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Superkomanda
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My Satellite Setup
0.8W; 4.8E; 13E (90cm),
19.2E; 28.2E; 36E (110cm),
DM800SE, DM600
My Location
Riga, Latvia
Hello there! :)
So I was talking with the friend today and he asked me, what's the bandwidth of transponders (I mean in "mbps")? And, I couldn't answer properly, so I would like to know.
As I know, there are 24 mbps on DVB-S. And there's no difference, if signal is in MPEG2 or MPEG4, bandwidth will be the same on transponder?
The next thing is DVB-S2. What's the bandwidth there? Thanks again! :)
 

BombedOne

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Rougly bandwidth equals SR-FEC. Say SR is 20000 and FEC is 1/2. Then bandwidth will be 20000-20000/2=10000.
 

BombedOne

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Rougly bandwidth equals SR-FEC. Say SR is 20000 and FEC is 1/2. Then bandwidth will be 20000-20000/2=10000.
 

Tsiklon

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The transponder will always have the same bandwith in terms of MHz. The data capacity (Mbps) will then be determined based on the modulation (DVB-S vs DVB-S2) and the error correction (FEC) employed. A higher power TP will require less error correction. A channel compressed in MPEG4 will require a lower data rate than one compressed in MPEG2.

The picture has a nice comparison for 36MHz TP.
 

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Tsiklon

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The transponder will always have the same bandwith in terms of MHz. The data capacity (Mbps) will then be determined based on the modulation (DVB-S vs DVB-S2) and the error correction (FEC) employed. A higher power TP will require less error correction. A channel compressed in MPEG4 will require a lower data rate than one compressed in MPEG2.

The picture has a nice comparison for 36MHz TP.
 

Bobben_no

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The capacity of a transponder can be calculated here if symbolrate, FEC etc. is known:
_http://www.satellite-calculations.com/Satellite/bitrates.htm

Some of the 33MHz DVB-S2 transponders on 1-west Thor5 T2 is currently transmitting at 66.8Mbits which gives room for 4 H.264 HDTV channels.
DVB-S2 for direct to home broadcasting should be able to deliver up to 80Mbit/s in 33MHz but it requires more EIRP than most satellites can provide (or a big receiving antenna).

A typical transponder for MPEG2 SD channels delivers around 38Mbit/s.
Symbolrate=27.500 FEC=3/4 gives 38Mbit/s in DVB-S.
Symbolrate=28.000 FEC=7/8 gives 45Mbit/s in DVB-S.
 

Bobben_no

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The capacity of a transponder can be calculated here if symbolrate, FEC etc. is known:
_http://www.satellite-calculations.com/Satellite/bitrates.htm

Some of the 33MHz DVB-S2 transponders on 1-west Thor5 T2 is currently transmitting at 66.8Mbits which gives room for 4 H.264 HDTV channels.
DVB-S2 for direct to home broadcasting should be able to deliver up to 80Mbit/s in 33MHz but it requires more EIRP than most satellites can provide (or a big receiving antenna).

A typical transponder for MPEG2 SD channels delivers around 38Mbit/s.
Symbolrate=27.500 FEC=3/4 gives 38Mbit/s in DVB-S.
Symbolrate=28.000 FEC=7/8 gives 45Mbit/s in DVB-S.
 
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