Radyne DMD2050, Operation Manual

Page: 47 / 214

Theory of Operation DMD2050 Universal Satellite Modem
3-22 TM110 - Rev. 1.3
Table 3-1. Reed-Solomon Codes
Type of
Service Data Rate
(Kbps)
R-S Code
(n, k, t)
1
Bandwidth
Expansion
[ (n/k) -1 ]
Interleaving
Depth
Maximum
2
R-S Codec
Delay (ms)
Small IDR
(With 16/15
O/H)
64
128
256
384
512
768
1024
1536
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
(126, 112, 7)
0.125
0.125
0.125
0.125
0.125
0.125
0.125
0.125
4
4
4
4
4
4
4
4
115
58
29
19
15
10
8
5
IDR
(With 96
Kbps O/H)
1544
2048
6312
8448
(225, 205,10)
(219, 201, 9)
(194, 178, 8)
(194, 178, 8)
0.0976
0.0896
0.0899
0.0899
4
4
4
4
9
7
2
<2
8PSK 1544
2048
6312
8448
(219, 201, 9)
(219, 201, 9)
(219, 201, 9)
(219, 201, 9)
0.0896
0.0896
0.0896
0.0896
8
8
8
8
18
13
4
3
DVB All (204, 188, 8) 0.0851 12 -
1. n = code length, k = information symbols and t = symbol error correcting capability.
2. Design objective.
3.15 DMD2050 Automatic Uplink Power Control (AUPC Operation)
The DMD2050 Modem has an optional built-in provision for Automatic Uplink Power Control
(AUPC). AUPC attempts to maintain a constant E
b
/N
o
at the receive end of an SCPC link. This is
especially useful when operating over a satellite at Ku-Band Frequencies in locations with high
rainfall periods.
Implementing Strap Code 26 can set the following modem configuration.
Refer to Table 4-4 for an explanation and tabular listing of available Strap
Codes. The Frequency and Modulator Output Power are set
independently of the strap code.