Operation Manual

Installation guidelines
50
BIU
CAUTION
Overdriving the RF source input into the BIU will cause permanent equipment failure and will void the warranty.
The installer must ensure that input levels are not exceeded. Plan for maximum power out of the RF source and
attenuate accordingly with external attenuators if needed.
The BIU serves as the RF interface between the RF source and the ICU/FOI. Each BIU is pre-set to a frequency band
and is not field tunable.
The BIU has two sets of RF source connections. The units can accept two independent feeds (within the same band).
The feeds can be from separate sources or A and B paths in a MIMO configuration.
Due to the high level of RF coming into BIU, use only quality RF cables.
BIU Type Minimum DL Input Maximum DL Input
Low Level -7dBm +7dBm
High Level +20dBm +33dBm
Figure 35 BIU Connections
RF
Source
ICU
or
FOI
 Install the BIU in the Master Unit (wide BIU uses two slots, slim BIU uses one slot).
CAUTION
When mating RF connectors, ensure that they are properly aligned and not cross threaded.
Tighten SMA connectors to 8 in.-lbs (0.9 N-m).
Do over torque RF connectors, this could result in damage to the Unit.
Do not under torque RF connectors, this could result in poor signal transmission.
Note: The UL1 and UL2 uplink test ports are 3dB lower than the signal on the corresponding DL/UL
BTS port.
 Connect SMA to the RF source. Tighten to 8 in-pounds (0.9 N-m) with a calibrated torque wrench.
 Connect QMA to the ICU/FOI.
CAUTION
Excess tension on the cable or connectors may cause PIM issues.
Cables must be secured in the rack without applying tension to the connectors.