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Descrambling types, Differential decoder, Bpsk bit ordering – Comtech EF Data SDM-300L3 User Manual

Page 324: Deinterleaver (reed-solomon codec), 3 descrambling types, 4 differential decoder, 5 bpsk bit ordering, 6 deinterleaver (reed-solomon codec)

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SDM-300L3 Satellite Modem

Revision 0

Specifications

MN/SDM300L3.IOM

14–18

14.7.3 Descrambling

Types

When descrambling is enabled, it is applied to the demodulator data according to the
programmed demodulator type as listed in Table 14-9. When descrambling is disabled, no
descrambling is applied to the demodulator data.

Table 14-9. Descrambling Types

Demodulator Type

FEC or Framing

Descrambling

EFD Closed, CSC Closed Sequential

ITU V.35

EFD Closed,
CSC Closed,
FDC Closed

Viterbi

ITU V.35 INTELSAT Modified

EFD Closed

Viterbi/RS Concatenated EFD Modified V.35

EFD Closed

Turbo

2

12-1

Synchronous

EFD CLosed

Turbo

IESS-315

EFD Closed

ASYNC

2

15-1

Synchronous

FDC Closed

Sequential or Viterbi

FDC Modified V.35

INTELSAT Open

Viterbi IDR

ITU V.35 INTELSAT Modified

INTELSAT Open

Viterbi IDR with RS

ITU V.35 INTELSAT Modified

INTELSAT Open

IBS, D&I, IESS-310

2

15-1

Synchronous

14.7.4

Differential Decoder

The differential decoder takes care of one set of ambiguities due the error correction codes
being transparent.

On or Off

14.7.5 BPSK

Bit

Ordering

The decoder has the ability to select whether I is the first bit or Q is the first bit in the
symbol word grouping for compatibility with any system. For standard mode Q is the first
bit.

Viterbi (Standard/Non-Standard)

Sequential (Standard/Non-Standard)

Turbo – fixed order only

14.7.6

Deinterleaver (Reed-Solomon Codec)

OQPSK, QPSK – Depth 4 (IBS, IDR, D&I)

8-PSK – Depth 4 (No overhead, IBS, D&I) (IESS-310)

Depth 8 (Closed Network, Async)

8-PSK – Depth 8 (IDR) (IESS-310)