TANDBERG TT1260 Satellite TV System User Manual


 
Introduction
Instruction Manual: TT1260 Standard Definition Professional Receiver/Decoder Page 1-11
ST.TM.E10100.1
1.3.2 Input Connections
The Satellite Receiver interfaces directly to Low-Noise Block (LNB) and
accepts an intermediate frequency (IF) input in the band 950 - 2150 MHz
(L-band) for operation in the specified symbol-rate range (see
Annex B, Technical Specification). The unit can provide dc power and
polarisation switching to the LNB.
1.3.3 What the Satellite Receiver Does
The Receiver can be tuned to a specified satellite channel frequency and
polarisation. The input is down-converted via a Low-Noise Block (LNB) to
provide an L-band input to the Receiver. The front-end tuning is
microprocessor controlled with a frequency synthesised local oscillator. A
software tuning and acquisition algorithm resolves translation errors
(mainly due to the LNB).
The signal is then passed to a demodulator that recovers the signal using
soft-decision decoding. The resulting stream is Reed-Solomon decoded and
descrambled to provide inputs to the Decoder circuit. The received channel
may contain multiple services, therefore the Receiver’s demultiplexer is
configured to select a single video service and other audio/data
components and present them at the output.
Figure 1.4: What the Satellite Receiver Does
TT1260 Satellite Receiver
f
n
f
n+1
f
n+2
f
n+3
f
n+4
horizontal
polarisation
vertical
polarisation
SHF
Low-Noise Block
L-band
Tune to a
satellite
channel
Select a
service from
the satellite
channel
Multi
p
le satellite channels
Multi
p
le services on the tuned satellite channel
Select the
components from
the chosen service
Video
Audio
Data
Trans
p
ort Stream
Multi
p
le com
p
onents on the selected service