HR
X
-C-HB-3
V
IA
L
ITE
HD
C-B
AND
L
INK
H
ANDBOOK
27
3.9
Link delay
The
ViaLiteHD
link introduces a small amount of delay to the system, similar to the contribution of an
amplifier. The typical delay contribution is shown below. You should also account for delay through
RF and fibre cables as these are likely to be much higher than the delay in the link fibre optic
modules.
Fibre optic link transmit and receive pair
13.5ns
Fibre optic cable
5ns per meter, check manufactures specification
RF cable
3.5
– 5.5 ns per meter dependent on cable type.
LMR-195
4.0 ns per meter
LMR-400
3.9 ns per meter
LMR-500
3.9 ns per meter
LMR-600
3.9 ns per meter
RG-58
5.1 ns per meter, dependent on dielectric
RG-59
4.1 ns per meter, dependent on dielectric
RG-213
5.1 ns per meter
RG-316
4.2 ns per meter
Delays quoted are typical for these cable types, construction of cables of the same type will vary
between manufacturers (i.e. foam/ PTFE/ solid polyethylene dielectric). If delay is critical please
check your manufacturer’s cable specification or electrically test the cables.
3.10 RF isolation
ViaLiteHD
cards are designed to offer excellent isolation between slots in a chassis mounted system.
The sensitive components and RF circuitry of
ViaLiteHD
C-band link modules are well shielded
3.10.1 RF isolation, plug-in cards
Measurements of two C-Band links in adjacent slots of a
ViaLiteHD
3U chassis show better than
60dB isolation.
-120
-100
-80
-60
-40
-20
0
0
1000
2000
3000
4000
5000
6000
7000
8000
Is
o
lation
(
d
B
)
Frequency (MHz)
C-Band Chassis Link to Link Isolation
Tx1_Rx2_Rx1
Tx1_Rx2
