Andrew ION-B Series, User Manual

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147 MN024-010
TBSI
Description
The TBSI module adjusts the signal
level between the donor source
and the ION-B system.
It has 2 independent variable
attenuators to adjust both the uplink
and downlink separately (please
refer to the BriteTool manual to
understand how to calculate the
right value of attenuation through
BriteTool software)
RF Ports
•
1 DL RF input port
•
1 DL RF output port (attenuated
signal)
•
1 UL RF input port
•
1 UL RF output port
(attenuated signal)
The attenuation required for both
the DL and UL can be properly set
through relevant knobs (30dB range,
1dB step).
TBSI Main Applications
The main applications of the TBSI module are:
• adjusting RF levels coming to/from a donor source:
ÿ The TBSI adjusts the DL signal to meet the required power level at the TFLN DL RF
input
ÿ The TBSI adjusts the RF UL signal coming from the TFLN master optical TRX in order
to meet the desired requirements for blocking level and receiver sensitivity to the
donor source
4.9. Base Station Interface TBSI
DL RF input port
(from donor source)
UL RF input port
(from donor source)
DL RF input port
(to master unit)
DL attenuation knob
UL RF input port
(from master unit)
Fig. 4.9.1: The TBSI Base Station Interface
UL attenuation knob