HTU-E1
HDSL Termination Unit
FEATURES
• Setup, control and
• HDSL NTU/LTU enabling
•
•
•
•
transmission of 2048 kbps
E1 data over unconditioned
twisted-pair lines
Extends the data
transmission range of up to
9.2 km (5.7 miles) with the
H-RPT repeater or up to
4.8 km (3 miles) without the
H-RPT repeater
Operates opposite RAD’s
HCD-E1, HTU-2 and H-RPT
Complies with the ETSI
HDSL standards
Supports unframed or
framed E1
•
•
•
•
•
monitoring using front
panel, ASCII terminal or
SNMP-based network
management station
Control of the remote unit
via embedded operation
channel or inband
management
Timeslot priority bumping
Call-out capabilities
supported via the control
port
Alarm buffer holding up to
100 alarms
Remote power feeding from
a modem card or standalone
unit
• Enhanced diagnostics
include:
Loopbacks on the HDSL
lines and E1 port
!
E1 and HDSL
performance statistics
collection
• High voltage line protection
in compliance with
ITU K.21
• Available as a standalone
unit or as a card for the
LRS-24 rack
!
HTU-E1
HDSL Termination Unit
DESCRIPTION
• HTU-E1 is an access unit that
converts the 2048 kbps E1 signals
into HDSL transmission format.
The conversion extends the
transmission range to cover
4.8 km (3.0 miles) over a 4-wire
link (24 AWG/0.5 mm) without
the need for repeaters or fiber
optic link.
• Transmission of HTU-E1 complies
with the ETSI HDSL standards.
Using advanced equalization,
adaptive filtering, echo
cancellation technology and 2B1Q
line coding, the unit compensates
for line impairments, bridge taps
and mixed cabling. High immunity
to background noise enables
transmission of the multiple HDSL
lines in the same physical cable.
• Setup, control and monitoring of
status and diagnostics information
can be performed using one of
the following:
! Front panel LCD with three
buttons, using menu-driven
management
! ASCII terminal connected
directly or via a dial-up modem
to the async control port using
command line interpreter
! SNMP management station
connected to the async control
port, using Serial Link Interface
Protocol (SLIP).
• An embedded channel in the
• The priority bumping feature
allows the user to select the
timeslot priority (high or low). In
this case, if one of the lines is
down, HTU-E1/HTU-E1L
continues to send data over the
HDSL link.
• Timeslot assignment is
programmable, allowing data from
the E1 port to be placed into
timeslots, either consecutively or
alternately. In addition, the central
HTU-E1 provides full user control
over the timeslot allocation of the
remote HTU-2/HCD-E1 data
ports, or HCD-E1 sublink.
HDSL transmission provides both
control and diagnostic capabilities
from the centrally-located HTU-E1
to the remote unit at the
customer’s premises. The user can
monitor the link and alarms, and
perform online configuration, as
well as diagnostic loopbacks to the
remote unit.
APPLICATIONS
Figure 1. Central Site Application with SNMP Management and Remote Power Feeding
HTU-E1
HDSL Termination Unit
• The standalone HTU-E1/PF and
HTU-E1C/P card provide remote
power feed for the HTU-E1L/P
unit or H-RPT HDSL repeater. For
the remote power feeding via the
HTU-E1C/P card, a standalone
power supply, LRS-PS-FEED,
should be ordered separately.
• HTU-E1/HTU-E1L supports
call-out of the alarm conditions
via its front panel control port.
• HTU-E1 supports an internal
SNMP agent and can be
controlled by the RADview SNMP
network management application,
as well as by any generic SNMP
station.
SPECIFICATIONS
HDSL INTERFACE
• Compliance
ETSI TR-152
• Line Code
2B1Q
• Line Baud Rate
584 kbaud (equivalent to
1168 kbps), for each pair
• Line Type
Two unconditioned, unloaded
twisted pairs
• Impedance
• Differential Line Delay
Maximum 50 µs at 150 kHz
• Equalizer
Automatic adaptive equalizer
• Connector
RJ-45
E1 INTERFACE
• Applicable Standards
ITU-T Rec. G.703, G.704, G.706,
G.732, G.823
• Framing
!
!
135Ω
• Transmit Pulse Shape
as per ETSI TR-152
• Transmit Signal Power
+13.5 dBm ±0.5 dBm
• Loop Loss
27 dB max at 150 kHz
(584 kbaud)
• Range
Without H-RPT:
! 3.8 km (2.4 miles) over 26 AWG
(0.4 mm)
! 4.8 km (3.0 miles) over 24 AWG
(0.5 mm)
With H-RPT:
! 7.2 km (4.5 miles) for 26 AWG
(0.4 mm)
! 9.2 km (5.7 miles) for 24 AWG
(0.5 mm)
• Return Loss
!
256N, no multiframe, intended
for use with CCS, without CRC-4
256N, no multiframe, intended
for use with CCS, with CRC-4
Unframed
• Nominal Line Data Rate
2048 kbps
• Line Code
HDB3
• Line Impedance
!
!
120Ω, balanced
75Ω, unbalanced
• Signal Levels
Transmit:
! ±3V ±10%, balanced
! ±2.37V ±10%, unbalanced
Receive: 0 to -10 dB
• Jitter Performance
Per ITU G.823
• Connectors
!
!
8-pin RJ-45 female, balanced
Two BNC coaxial, unbalanced
16 dB minimum, 25 kHz to
317 kHz at 135Ω
Figure 2. Extending the HTU-E1 Operation Range via the Remote Power-Fed H-RPT Repeater
HTU-E1
HDSL Termination Unit
SUPERVISORY PORT
HTU-E1, HTU-E1/PF
• Interface
V.24/RS-232
• Type
DCE
• Data Rate
0.3, 1.2, 2.4, 4.8, 9.6 kbps, with
Autobaud option
• Word Format
!
!
!
!
One start bit
7 or 8 data bits
Parity: none, odd, or even
One stop bit
• Connector
9-pin D-type, female
HTU-E1L
Proprietary 20-pin connector
HTU-E1C
Via CM-2 connector of LRS-24
rack
GENERAL
• Timing
Central Unit:
! Internal, derived from local
oscillator
! External, locked to recovered E1
clock signal
Remote Unit:
! Loopback timing, derived from
incoming HDSL receive clock
• Diagnostics
Loopbacks:
! Local loopback on the E1 port of
the local HTU-E1
! Local loopbacks on the two
HDSL lines
! Remote loopback on the E1 port
of the local HTU-E1
! Remote loopback on the E1 port
or data channel of the remote
unit
! H-RPT local line loopback
towards the LTU-configured unit
Statistics:
! HDSL performance statistics
collection as per ITU-T Rec.
G.826
! E1 performance statistics
collection with CRC-4 as per
ITU-T Rec. G.706 or BPV count
without CRC-4
• Indicators
HDSL interface (per loop):
HDSL LOS – Loss of Sync
E1 interface:
LOC LOS – Local Loss of Sync
REM LOS – Remote Loss of Sync
TST – Test
ALM – Alarm
• Physical
HTU-E1:
Height:
Width:
Depth:
Weight
44.3
21.5
24.3
1.5
mm
cm
cm
kg
/ 1.75
/ 8.5
/ 9.5
/ 3.5
in
in
in
lb
HTU-E1/PF:
Height: 44.3
Width:
43.2
Depth:
26.0
Weight 2.1
mm
cm
cm
kg
/ 1.75
/ 17.0
/ 10.2
/ 4.6
in
in
in
lb
!
!
!
!
HTU-E1: 3.4W
HTU-E1L: 3.0W
HTU-E1/PF: 11W
HTU-E1C: 3.8W
• Line Protection
HTU-E1L/N/*/+
HDSL network termination unit
HTU-E1/PF/N/*
HDSL termination unit, remote
power feeding version
HTU-E1CB/N/+
Card version for ANSI LRS-24 rack
* Specify power supply:
AC for 100 to 240 VAC
48 for -48 VDC
+ Specify P for phantom feeding
version of HTU-E1C or
phantom-fed version of HTU-E1L
AC: 100 to 240 VAC, 50 or 60 Hz
DC: -48 VDC (-36 to -72 VDC)
Remote power feed:
! From HTU-E1/PF
! From LRS-PS-FEED via
HTU-E1C/P
• Power Consumption
HTU-E1/N/*
HDSL termination unit
HTU-E1CF/N/+
Card version for ETSI LRS-24 rack
HTU-E1C:
Fits the dimensions of the LRS-24
rack
• Power Supply
ORDERING
LRS-PF-FEED
Standalone power supply for remote
power (phantom) feeding
RM-17
Special hardware for mounting one or
two HTU-E1/HTU-E1L units in a
19-inch rack
RM-7/NEW
Special hardware for mounting one
HTU-E1/PF unit in a 19-inch rack
According to ITU K.21
• Environment
Temperature: 0–50°C/32–122°F
Humidity:
Up to 90%,
non-condensing
 2000 RAD Data Communications Ltd.
All other trademarks are the property of their respective holders.
652-100-12/00
Specifications are subject to change without prior notice.