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Input connections, What the satellite receiver does, 2 input connections – TANDBERG TT1260 User Manual

Page 19: 3 what the satellite receiver does

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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

Multiple

satellite channels

Multiple services on the tuned satellite channel

Select the

components from

the chosen service

Video
Audio
Data
Transport Stream

Multiple components on the selected service