User's Manual Part 1

2.2. The Britecell Plus Master Unit
Below are listed the Britecell Plus modules. For further details about these components, refer to the
next chapters of this manual
.
The Sub-rack (TPRN) is a 19” subrack hosting
the Britecell Plus modules; it accommodates 12
slots, whose sizes are 7 TE x 4 HE. As each
Britecell Plus module takes up one or two slots,
each Master Unit can sustain up to 12 modules,
depending on design configuration and
requirements.
The Local Unit (TFLN): in downlink it provides
an RF-to-optical conversion of the signal coming
from the BTS, and transmits it to 4 optical
outputs, so as to feed 4 TFAxxx. In uplink it
provides optical-to-RF conversion for 4 optical
signals coming from RUs, and it combines them
into a single RF output, while providing automatic
gain control in order to balance the fibre losses.
Module dimensions:
Width = 7TE, Height = 4HE (one slot in the
Master Unit).
The duplexer (THYN): it combines the downlink
(DL) and uplink (UL) paths into a single one,
while maintaining the required isolation. The
module dimensions are: Width = 7TE, Height =
4HE.
The variable RF attenuators (TBSI and TDI):
they provide independent attenuations (adjustable
from 0 to 30dB, with 1dB steps) on uplink and
downlink RF paths, and allow the designer to
optimize the signal level close to the BTSs. TBSI
is an override attenuator, while TDI is a digital
attenuator also providing 20dB gain on the UL
path. Their dimensions are:
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User Manual