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SatcoDX - TELE-satellite International Magazine

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74 <strong>TELE</strong>-<strong>satellite</strong> & Broadband — 10-11/2008 — www.<strong>TELE</strong>-<strong>satellite</strong>.com<br />

▲ A look inside the video room. Here the programming<br />

clips are put together, sent terrestrially<br />

by microwave link to SNAI headquarters in<br />

Rome, then back again and then uplinked to the<br />

<strong>satellite</strong> at 16 east.<br />

seen by the customer who then opts away<br />

from HD.”<br />

He does see HDTV coming in the future<br />

but not as fast as originally hoped. He<br />

calculates that the savings that DVB-S2<br />

and MPEG4 bring with it don’t compensate<br />

for the extra costs customers would<br />

need to pay for new receivers.<br />

His arguments for the new fiber optic<br />

LNBs from Global Invacom that <strong>TELE</strong><strong>satellite</strong><br />

recently introduced are similar:<br />

“Fiber optic technology is coming; it is<br />

beginning to develop in this direction”,<br />

observes Mario, but he is also skeptical<br />

about seeing this in the near future.<br />

Before we left, Mario gave us a hot tip<br />

for DXers: “Most feeds today are transmitted<br />

in 8PSK – but few DXers can<br />

receive them.” Why? Isn’t 8PSK used with<br />

DVB-S2? “Yes, this is true”, explained<br />

Mario, “but feeds don’t transmit in DVB-<br />

S2, instead it is normal DVB-S.” The<br />

problem lies with the readily-available<br />

LNBs: “There’s not only the noise factor”,<br />

explains Mario, “you also have phase<br />

noise. With a high-quality spectrum analyzer<br />

you can see that the carrier drifts<br />

very easily.”<br />

“As long as it drifts fairly slowly, the<br />

receiver is able to follow along. But if<br />

the drift is random, phase noise makes<br />

it impossible to demodulate the 8PSK<br />

constellation, and reception fades away.”<br />

Mario told us of his experiences: “Pro-<br />

In the heart of Teleippica: from here the five<br />

encoders are controlled and the programming is<br />

switched over to the uplink. Susanna DelPapa is<br />

in charge of this control room.<br />

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