Comtech EF Data SDM-9000 - Manual (Page 197)

SDM-9000 Satellite Modem Options
Rev. 4 A–11
I
Q
DATA
CLOCK
SYNC
DATA
CLOCK
Q
SYNC
I
BASEBAND
PHYSICAL
INTERFACE
and
DE-JITTER
FIFO
SYNC
DECODER
(Correlator)
2047 AND
AIS
GENERATORS
SYNC 1
INVERSION
and
SCRAMBLER
REED-
SOLOMON
CODER
(Outer Coder)
DEPTH 12
INTERLEAVER
K = 7
CONVOLUT.
ENCODER
PUNCTURING
and
MAPPING
(Inner Coder)
NYQUIST
FILTERS
(35% SRC)
TO QPSK
MODULATOR
A) TRANSMIT PROCESS
FROM QPSK
DEMODULATOR
NYQUIST
FILTERS
(35% SRC)
MAPPING
and
DEPUNCTUR.
VITERBI
DECODER
(Inner Decoder)
SYNC
DECODER
(Correlator)
DEPTH 12
DEINTERLEAV.
REED-
SOLOMON
DECODER
(Outer Decoder)
DESCRAMBLE
and
SYNC 1
INVERSION
DOPPLER
BUFFER
BASEBAND
PHYSICAL
INTERFACE
2047 and
AIS DETECT
B) RECEIVE PROCESS
Figure A-6. Block Diagram of SDM-9000 Configured for DBS/DVB Operation
A.2.1 Requirements
This section covers the module types that are compatible with each option, and the
minimum software requirements for the modem PCBs. The following options list the
interface type and PCB assembly numbers.
The DBS option works in conjunction with the Viterbi decoder, and includes additional
framing, interleaving, and Codec processing to provide:
•
Concatenated FEC
•
Convolutional encoding/decoding
This option can be factory or user installed. Refer to the following table for modem
compatibility requirements.
Interface PCB Type 2 or 3 (or greater)
AS/4477-22 PECL w/buffer
AS/4477-32 PECL w/ESC
AS/4477-21 ECL w/buffer
AS/4477-31 ECL w/ESC
Display/M&C PCB AS/2305 Rev. C4 (or greater)
Modulator PCB AS/3969
Demodulator PCB AS/3970-5 or AS/3970-6
DVB Reed-Solomon PCB AS/4524