Motorola SG 2000 用户手册
O v e r v i e w
2 - 7
SG 20 00 Ins tal la tion and O pera tion M anua l
Refer to the current Motorola catalog for option and feature availability.
F o rwa rd Pa th
The multiple receiver functionality of the platform accommodates split-band and/or redundancy
applications. A typical split-band configuration has analog signals in the 52 MHz through 550 MHz
band feeding one receiver (C location in Figure 2-6). Digital transmissions or narrowcast signals are
carried between 450/550 MHz and 870 MHz on another fiber and processed by the second receiver
(A location). You can use the optional third receiver (B location) as a back up in the event that the
narrowcast receiver loses optical signal input. Automatic path switchover occurs through either the
optional status monitoring or manual control-board modules.
applications. A typical split-band configuration has analog signals in the 52 MHz through 550 MHz
band feeding one receiver (C location in Figure 2-6). Digital transmissions or narrowcast signals are
carried between 450/550 MHz and 870 MHz on another fiber and processed by the second receiver
(A location). You can use the optional third receiver (B location) as a back up in the event that the
narrowcast receiver loses optical signal input. Automatic path switchover occurs through either the
optional status monitoring or manual control-board modules.
Figure 2-6 provides a diagram of the signal flow-path through the SG 2000:
F i g u r e 2 - 6
Si g n a l f l o w d i a g r a m
Si g n a l f l o w d i a g r a m
SG2-FJB/P
forward
jumper
board
forward
jumper
board
Data lines
Splitter
Splitter
Splitter
TP
TP
TP
TP
TP
JXP
JXP
JXP
Receiver B
Receiver C
Receiver A
SG2-FBS
forward
band
split
forward
band
split
MDR
Attenuator
SG2-FRB
POT
ADU
JXP
+ 18.5
Amplifier
JXP
EQ
Amplifier
SG2 lid
SG2 RF chassis
+24 VDC
+5 VDC
ACV
+5 VDC
ACV
JXP
L
H
Diplex
filter
TP
L
H
Diplex
filter
TP
L
H
Diplex
filter
TP
L
H
Diplex
filter
JXP
Ingress
JXP
JXP
TP
TP
Optical transmitter
Optical transmitter
JXP
JXP
SG2-ABJ/P
forward
A/B
jumper
forward
A/B
jumper
JXP
EQ
Amplifier
Ingress
JXP
EQ
Amplifier
Ingress
Status monitor
Switch
TP
-0.5
SG2-RPM/S
SG2-RPLPF
LP filter
LP filter
-3.5
-2.0
-2.0
-1.5
-1.0
-0.5
-2.0
-0.5
-0.5
JXP
EQ
Amplifier
-1.0
-1.0
+18.5
-8.0
-2.0
@ Min atten
+15 Lo
+21.5 Hi
+21.5 Hi
Power supply
TP
TP
Power supply
Ingress
LP filter
SG2-RPM/C
SG2-RPLPF
-3.5
-3.5
-3.5
+8.5
-2.0
Ingress control
JXP
JXP
HP
filter
-1.5
-1.0
All forward and return path test points (TP) are -20dB
5dB
With second transmitter pad = 5dB; without second transmitter pad = 15dB
5dB
With second transmitter pad = 5dB; without second transmitter pad = 15dB
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