Installation Instructions

2.13
Low Noise Amplifier
The low noise amplifier is included in a multicoupler unit and gets its signal from the rx port of the
duplexer and supplies enough gain to overcome the losses between the duplex filter and the input of
the point of interface modules. The gain from the top of the rack to the input of the point of interface is
nominally 20dB
The gain is adjusted via the DIP switches located on the front of the receiver multicoupler unit.
12V DC is supplied to one of the multicoupler inputs from the 48V/12V DC/DC converter mounted on
the outer edges of the DIN rail assembly. The multicoupler draws a max of 257mA.
Redundancy is supplied by having the LNA of only one MIMO path of each sector connected to the
same DC/DC converter. If one converter were to fail, one MIMO path of a sector would still be
unaffected.
Physical specifications:
Dimensions: 267mm x 32mm x 125mm (10.51" x 1.26" x 4.92")
Weight: 1.4 lbs
Figure 20: Multicoupler/LNA
2.14
DIN Rail Components
The DIN Rail located vertically between the BBU and the PA/LNA 48V power supplies and across the
back of the rack. It is accessible from the front of the rack.
The DIN Rail holds two LNA 12V converters, 2 associated 6A circuit breakers (one per converter) and
six 32A circuit breakers, (one for each power amplifier).
TBD
Chapter
2 : 900 MHz eNodeB Description
28
Exhibit D page 29 of 38