Nera Saturn Bm Marine Mk2, Technical Manual

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17
Saturn Bm Mk2 Marine – Technical Manual
O-QPSK Encoded Signal
(O-QPSK = Offset Quadrature Phase Shift Keying)
t
0
°
+90
°
+270
°
+180
°
0
°
+90
°
+270
°
+180
°
SCPC Channel (Single Carrier Per Channel)
In-band Signalling Mode
Forward Direction
MES LES
ADE
* Unique Word:
0111 1000 1001
for 1st subframe, and
1000 0111 0110
for 2nd, 3rd and 4th
subframe (compliment)
DUMMY
CW
24 bits
SUB
32 bits
SU1
60 ms
* UW
24 bits
FLUSH
8
bits
FLUSH
DUMMY
6 bits
Before FEC
coding
6 bits
SU1 SU1
96 BIT
SIGNALLING UNIT
384 bits
8
bits
SU
SUBFRAME - 4
SU
SUBFRAME - 3
SU
SUBFRAME - 2
SU
SUBFRAME - 1
60 ms 60 ms 60 ms 60 ms
n x 240 ms
END OF
DATA
192 bits
CONTIN.
WAVE
96 bits
BIT
TIMING
64 bits
IN-BAND SIGNALLING FRAME
1920 bits
IN-BAND SIGNALLING FRAME
1920 bits
240 ms 240 ms 24 ms
OCTET
No.
1
2
3
4
5
6
7
8
9
10
11
12
8 7 6 5 4 3 2 1
BIT No.
SIGNALLING UNIT – SU
CCITT CRC
(CYCLIC REDUNDENCY CHECK)
SPARE
(Random binary bits)
MES ID MESSAGE
TYPE
Octet No. 1 Octet No. 2 Octet No. 3 Octet No. 4 Octet No. 5 Octet No. 6 Octet No. 7 Octet No. 8 Octet No. 9 Octet No. 10 Octet No. 11 Octet No. 12
SIGNAL UNITS = 12 "OCTETS" = 96 BIT SIGNALLING UNIT.
EXAMPLE: SCRAMBLING VECTOR ACKNOWLEDGE
95
H
4A
H
09
H
EC
H
DD
H
18
H
09
H
F1
H
BC
H
06
H
79
H
D5
H
LES ID
LES_SIG
SIGNALLING
CHANNEL
1 0 0 1 0 1 0 1 1 1 1 0 1 1 0 0 1 1 0 1 1 1 0 1 0 0 0 1 1 0 0 0 0 0 0 0 1 0 0 1 1 1 1 1 0 0 0 1 1 0 1 1 1 1 0 0 0 0 0 0 0 1 1 0 0 1 1 1 1 0 0 1 1 1 0 1 0 1 0 1 0 1 0 0 1 0 1 0 0 0 0 0 1 0 0 1
Message type
MES ID
LES ID
CCITT CRC
spare
95
M21
SCRAMBLING VECTOR ACKNOWLEDGE
S y s t e m D e s c r i p t i o n
S y s t e m D e s c r i p t i o n S y s t e m D e s c r i p t i o n SCPC Signalling
Duplexer
RF Unit
HPA
Combiner/splitter
LNA
Stable Platform
Right Hand Circular
polarized RF signal f = 1530 - 1559 MHz
-- 20 of 30 LRC Prüfung