User Manual
Table Of Contents
- SECTION 1: Overview
- SECTION 2: Description
- SECTION 3: Host Unit Installation
- SECTION 4: Operation
- SECTION 5: Maintenance
- SECTION 6: General Information
- ABOUT THIS MANUAL
- RELATED PUBLICATIONS
- ADMONISHMENTS
- GENERAL SAFETY PRECAUTIONS
- STANDARDS CERTIFICATION
- LIST OF ACRONYMS AND ABBREVIATIONS
- SECTION 1: Overview
- SECTION 2: Description
ADCP-75-116 • Issue A • August 2001 • Section 2: Description
Page 2-4
©
2001,
ADC
Telecommunications,
Inc.
signal.
In
SMR
installations,
the
HU
can
be
connected
directly
to
the
BTS
without
a
LRCS
Interface
Unit.
The
HU
should
be
as
close
as
possible
to
the
BTS
to
minimize
cable
losses.
2.5 RF Signal Adjustments
The
HU
is
equipped
with
two
digital
attenuators
for
adjusting
the
signal
levels
of
the
forward
and
reverse
path
RF
signals.
The
attenuators
provide
an
attenuation
adjustment
range
of
0
to
30
dB
and
can
be
set
in
1
dB
increments.
The
forward
path
attenuator
adjusts
the
level
of
the
input
RF
signal.
Any
input
signal
with
a
level
of
–10
dBm
(attenuator
set
to
30
dB)
to
–40
dBm
(attenuator
set
to
0
dB)
can
be
adjusted
to
the
required
level
of
–40
dBm
using
the
forward
path
attenuator.
An
external
attenuator
is
required
if
more
than
30
dB
of
attenuation
is
required
to
adjust
the
input
RF
signal
to
the
required
level.
An
overdrive
limiter
protects
the
system
against
excessive
inputs
but
does
not
function
during
normal
operation.
The
reverse
path
attenuator
adjusts
the
level
of
the
output
RF
signal
and
will
add
from
0
dBm
of
gain
(attenuator
set
to
30
dB)
to
30
dBm
of
gain
(attenuator
set
to
0
dB)
to
the
output
signal.
The
attenuators
are
software
controlled
and
are
adjusted
through
the
NOC
NEM
interface
or
the
EMS
software
MI.
The
HU
forward
and
reverse
path
propagation
delay
may
be
adjusted
in
1
µs
increments
within
a
range
of
0–63
µs.
The
propagation
delay
is
software
controlled
and
may
be
adjusted
through
the
NOC
NEM
interface
or
the
EMS
software
MI.
2.6 Optical Link Connection
Optical
link
connections
between
the
HU
and
the
RU
(STM)
are
supported
through
either
two
(non-diversity
unit)
or
three
(diversity
unit)
SC-type
optical
connector
ports.
On
non-diversity
units,
one
port
is
used
for
connecting
the
forward
path
optical
signal
and
the
other
port
is
used
for
connecting
the
primary
reverse
path
optical
signal.
On
diversity
units,
a
third
optical
port
is
used
for
connecting
the
diversity
reverse
path
optical
signal.
2.7 Controller Area Network Interface Connection
Controller
Area
Network
(CAN)
interface
connections
between
multiple
HUs
are
supported
by
a
pair
of
RJ-45
jacks.
One
of
the
jacks
is
designated
as
the
network
IN
port
and
the
other
jack
is
designated
as
the
network
OUT
port.
The
CAN
interface
allows
up
to
15
HUs
to
be
connected
together
(in
daisy-chain
fashion)
and
controlled
through
a
single
Digivance
EMS
computer.
2.8 Service Interface Connection
The
service
interface
connection
between
the
HU
and
the
Digivance
EMS
computer
is
supported
by
a
single
DB-9
female
connector.
The
service
connector
provides
an
RS-232
DTE
interface.
When
multiple
HUs
are
networked
together,
the
supporting
EMS
computer
may
be
connected
to
the
service
connector
on
any
one
of
the
networked
HUs.
The
unused
service
connectors
on
networked
HUs
may
also
be
used
to
provide
a
direct
connection
between
a
laptop
computer
(loaded
with
the
EMS
software)
and
the
corresponding
HU.