Comtech EF Data SDM-300A, Installation And Operation Manual

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SDM-300A Satellite Modem Options
Rev. 4 A–61
The Reed-Solomon Codec works in conjunction with the Viterbi decoder and includes
additional framing, interleaving, and Codec processing to provide concatenated FEC and
convolutional encoding and decoding.
Refer to Figure A-15 for a block diagram of the Reed-Solomon Codec.
C H A S S IS
IN T E R FA C E
C D R DATA
L O O P B A C K
T X D ATA
T X C LK
M U X D ATA
M U X C LK
IN T E R FA C E
P C B
M U X
C D R C L K
D E C D ATA
O V E R H E A D
P R O C E S S O R
R X
D ATA
LO O P B A C K
M U X
D M X D ATA
DM X C L K
R X C L K
D E C C LK
R E E D -SO LO M O N
M A IN
M A IN
P C B
Figure A-15. Reed-Solomon Codec Block Diagram
A.2.1.1 Specifications
Refer to Table A-20 overhead types and data rates supported by the Reed-Solomon
Codec option are listed below. Refer to
Chapter 1 for BER specifications.
Table A-20. Specifications
Overhead Type Data Rate
IDR (T1) 1640 kbit/s
IDR (E1) 2144 kbit/s
D&I 64 to 1920 kbit/s
IBS 64 to 2048 kbit/s
ASYNC 2.4 to 2048 kbit/s
No Overhead 2.4 to 4.555 kbit/s