Chapter 1

1.3.3What the Satellite Receiver Does

The Receiver can be tuned to a specified satellite channel frequency and polarization. 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 synthesized 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 1.2 What the Satellite Receiver Does

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EN/LZT 790 0005 R1A