Wavetek Wandel Goltermann ANT-20 User manual

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Recommendations and/or Standards of the
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Wavetek Wandel Goltermann
Eningen GmbH & Co.
Mühleweg 5, 72800 Eningen u. A.
© 2000
Author: MDD/TD
Translator: JohnNutley
Order no.: BN 3035/98.23
Edition: 08/00.07(V 7.20)
Previous edition:
07/00.04(V 7.1)
Subject to change without notice
Our normal guarantee and delivery
terms apply
Printed in Germany

ANT-20/ANT-20E PDH MUX/DEMUX
i
Contents
Introduction
1 Multiplex and demultiplex functions . . . . . . . . . . . . . . . . . . . . . . . . .I-1
2 Testing switch and sensor functions . . . . . . . . . . . . . . . . . . . . . . . . .I-2
3 In-service monitoring of tributary channels . . . . . . . . . . . . . . . . . . .I-2
Specifications
1 Generator section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-1
1.1 Frame generator, 64k/140M PDH MUX/DEMUX Chain
(option BN 3035/90.30). . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-1
1.2 Frame alignment signals. . . . . . . . . . . . . . . . . . . . . . . . . . . .S-1
1.2.1 Frame bit modifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-1
1.2.2 CRC checksum (PCM 30 CRC / PCM 31 CRC) . . . . . . . . . .S-2
1.3 Justification as per ITU-T G.742 and G.751 . . . . . . . . . . . . .S-2
1.3.1 PDH tributary offset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-2
1.4 Error insertion (anomalies) . . . . . . . . . . . . . . . . . . . . . . . . . .S-3
1.5 Alarm generation (defects) . . . . . . . . . . . . . . . . . . . . . . . . . .S-3
1.6 Test signals for bit error rate measurements. . . . . . . . . . . . .S-3
1.6.1 Internal test signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-3
1.6.2 External signal (with option 3035/90.20 only) . . . . . . . . . . . .S-3
1.6.3 Filler signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-3
2 Receiver section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-4
2.1 Frame systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-4
2.2 Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-4
2.2.1 Frame bit evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-4
2.2.2 CRC evaluations (PCM 30 CRC / PCM 31 CRC) . . . . . . . . .S-4
2.3 Offset measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .S-5
2.4 Error measurements (anomalies) . . . . . . . . . . . . . . . . . . . . .S-5
2.5 Alarm detection (defects) . . . . . . . . . . . . . . . . . . . . . . . . . . . S-5
2.6 Evaluation of test signals for bit error measurements. . . . . . S-5
2.6.1 Internal evaluation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-5
2.6.2 External signal (with option 3035/90.20 only) . . . . . . . . . . . .S-5

PDH MUX/DEMUX ANT-20/ANT-20E
ii
3 Drop&Insert / Through Mode / Block&Replace . . . . . . . . . . . . . . . S-6
3.1 Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-6
3.1.1 Clock generator. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-7
3.1.2 Anomaly insertion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-7
3.1.3 Defect generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-7
3.1.4 Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-8
3.2 Signal outputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-8
3.2.1 AUXILIARY signal output [11], electrical. . . . . . . . . . . . . . . . S-8
3.2.2 LINE/AUXILIARY signal output [13], electrical . . . . . . . . . . . S-8
3.3 Signal inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . S-9
3.3.1 AUXILIARY signal input [10], electrical. . . . . . . . . . . . . . . . . S-9
3.3.2 LINE/AUXILIARY signal input [12], electrical . . . . . . . . . . . S-10

ANT-20/ANT-20E PDH MUX/DEMUX
Introduction I-1
Introduction
Options BN 3035/90.30 to BN 3035/90.32
1 Multiplex and demultiplex functions
The ANT-20 can generate and analyze PDH frames with complete channel structures at rates
of 2, 8, 34 and 140 Mbit/s when fitted with the PDH Multiplexer/Demultiplexer Chain option. This
allows testing of the multiplex functions of individual hierarchy levels right up to tests covering
all hierarchies from 140 Mbit/s down to 64 kbit/s including linking to SDH signals via the
appropriate mapping stages.
Fig. I-1 TX signal structure
34 M
8 M
2 M
8 M
140 M
8 M
Path multiplexer
34 M
34 M
2 M
64 k
TP
Test pattern in one 64 kbit/s channel
Filler pattern in all other channels
2 M
64 k
Filler pattern in all channels
8 M
2 M
Test pattern
(TP)
TP
TP
Path multiplexer

PDH MUX/DEMUX ANT-20/ANT-20E
I-2 Introduction
2 Testing switch and sensor functions
Switch functions
SDH and PDH network elements process the PDH signals of various hierarchy levels.
Complex, interleaved signal paths occur, particularly in modern SDH network nodes (cross-
connects). The linking of the PDH multiplex chain to the SDH mapping functions in the ANT-20
makes the instrument ideal for testing complex switching functions. Since the ANT-20 can
generate and evaluate structured signals right down to the 64 kbit/s level, it can test switching
functions on all hierarchy levels from 140 Mbit/s to 64 kbit/s. Tests can be performed between
two SDH ports or between an SDH and a PDH port.
Alarm sensor test
Comprehensive facilities for inserting errors into the PDH signal at various hierarchy levels
allow testing of the monitor functions built in to the network elements. This is particularly useful
during installation work, as the network management systems are dependent on the correct
functioning of these sensors during subsequent operation.
3 In-service monitoring of tributary channels
The demultiplex function provides access to the tributary channels right down to the 64 kbit/s
level. This permits pinpoint in-service monitoring of individual channels in PDH signals and in
SDH signals when the appropriate mappings are employed.

Specifications S-1
ANT-20/ANT-20E PDH MUX/DEMUX
Specifications
Options BN 3035/90.30 to BN 3035/90.32
1 Generator section
1.1 Frame generator, 64k/140M PDH MUX/DEMUX Chain (option BN 3035/90.30)
The following frames are available:
The multiplexer chain (BN 3035/90.30) allows generation of a completely structured signal from
64 kbit/s to 140 Mbit/s.
1.2 Frame alignment signals
Frame alignment signals (FAS) corresponding to ITU-T recommendations G.751, G.742 and
G.704.
1.2.1 Frame bit modifications
The following bits can be statically programmed:
Bit ratekbit/s Frame conforming to: Notes
2048 ITU-T G.704 PCM 30, PCM 30 CRC, PCM 31 and
PCM 31 CRC systems
8448 ITU-T G.742 PCM 120 system
34368 ITU-T G.751 PCM 480 system
139264 ITU-T G.751 PCM 1920 system
Table S-1 Frame generation
PCM 1920 (G.751) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FAS bit nos. 13, 14, 15, 16
PCM 480, 120 (G.751, G.742) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . FAS bit nos. 11, 12
PCM 30/31 (G.704) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NFAS bit nos. 3 through 8
PCM 30/31 CRC (G.704) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .NFAS bit nos. 3 through 8

S-2 Specifications
PDH MUX/DEMUX ANT-20/ANT-20E
The following bits can be dynamically programmed:
Bits Sa4 thruogh Sa8 can be selected and each loaded with a freely programmable pattern 8 bits
in length. This permits transmission of Sasequences.
For PCM 30 / PCM 30 CRC systems, frame 0 or 1 in timeslot 16 can be loaded with a freely
programmable 8 bit word. Frames 2 through 15 can be loaded with a further freely
programmable 8 bit word.
1.2.2 CRC checksum (PCM 30 CRC / PCM 31 CRC)
The ANT-20 calculates the CRC checksum for the measured channel and the filler channels as
per ITU-T recommendation G.704 and inserts the result bits at the appropriate position in the
pulse frame.
1.3 Justification as per ITU-T G.742 and G.751
The bit rates in the upper and subordinate systems are in a fixed relationship to each other.
Justification is at a nominal rate (offset of upper and subordinate systems is identical).
Exception: Insertion of external signals.
1.3.1 PDH tributary offset
Static offset for the PDH tributary bit rates during insertion into the SDH container.
The offset is an average value. The actual offset at any given time may be above or below this
value.
PCM 30/ PCM 30 CRC (G.704). . . . . . . . . . . . . . NFAS bit nos. 4 through 8 (Sa4 through Sa8)
Upper system
bit rate in kbit/s ITU-T Justification ratio Nominal justification rate
in kbit/s
8448 G.742 0.42424 4.226
34368 G.751 0.43575 9.750
139264 G.751 0.41912 9.934
Table S-2 Justification
Offset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .±100 ppm
for all bit rates, relative to SDH container
Step width . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 ppm

Specifications S-3
ANT-20/ANT-20E PDH MUX/DEMUX
1.4 Error insertion (anomalies)
In addition to the error types described in the “Specifications” for the mainframe instrument, the
following anomalies can be inserted:
The insertion of errors (anomalies) or alarms (defects) are mutually exclusive. The action
selected first is active.
1.5 Alarm generation (defects)
The alarm types are described in the “Specifications” for the mainframe instrument.
The insertion of alarms (defects) or errors (anomalies) are mutually exclusive. The action
selected first is active.
1.6 Test signals for bit error rate measurements
1.6.1 Internal test signals
Bit patterns as in the mainframe instrument:
1.6.2 External signal (with option 3035/90.20 only)
An external signal with bit rate 34 368 kbit/s (coaxial), 8 448 kbit/s (coaxial) or 2 048 kbit/s
(coaxial or balanced) can be inserted into the selected timeslot instead of the bit pattern
(see Sec. 1.6.1).
The interfaces for this signal are described in the “Specifications” for the STM-1 mapping
options.
1.6.3 Filler signals
Complete structured signals using the pseudo-random bit sequence PRBS 6 are transmitted in
all timeslots except the selected timeslot in all 64 kbit/s channels.
Error type, anomaly1Single Rate2
CRC-4 yes 2E-3 to 1E-8
E bit yes 2E-3 to 1E-8
1 For PCM 30 CRC and PCM 31 CRC only
2 A CRC word error rate is inserted
Table S-3 Available error types (anomalies) in addition to the mainframe instrument
•Transmitted in all timeslots (framed pattern to ITU-T O.150/O.151)
•Transmitted in a selected timeslot

S-4 Specifications
PDH MUX/DEMUX ANT-20/ANT-20E
2 Receiver section
2.1 Frame systems
Frames which can be evaluated by the 64k/140M PDH MUX/DEMUX chain and
64k/140M PDH DEMUX chain (options BN 3035/90.30 and 3035/90.31)
All timeslots can be selected for all PCM frame structures. These may be speech or data
channels in a primary rate system or the tributary channels in a justified multiplex system.
2.2 Evaluation
2.2.1 Frame bit evaluation
The following bits are evaluated and displayed:
For PCM30/31 CRC systems, one of the bits Sa4 through Sa8 can be selected in order to
display pattern sequences of up to 8 bits in length.
The D alarm bits (RDI alarms) are also evaluated and indicated by means of LEDs.
Also see in the ”Specifications” of the mainframe instrument.
2.2.2 CRC evaluations (PCM 30 CRC / PCM 31 CRC)
Errored CRC words are evaluated in the selected channel (CRC word error count).
The equivalent CRC bit error ratio is calculated from the CRC word error ratio.
The number of E bit errors is also converted to the equivalent bit error ratio.
Bit rate kbit/s Frame conforming to Notes
2048 ITU-T G.704 PCM 30, PCM 31 systems
2048 ITU-T G.704/G.706 PCM 30 CRC, PCM 31 CRC systems
8448 ITU-T G.742 PCM 120 system
34368 ITU-T G.751 PCM 480 system
139264 ITU-T G.751 PCM 1920 system
Table S-4 Frame systems for individual system bit rates
PCM 1920 (G.751) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .FAS bit nos. 13, 14, 15, 16
PCM 480, 120 (G.751, G.742). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .FAS bit nos. 11, 12
PCM 30/31 (G.7049) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . NFAS bit nos. 1 through 8
PCM 30/31 CRC (G.704). . . . . . . . . . . . . . .NFAS bit nos. 2 through 8 (A bit, Sa4 through Sa8)

Specifications S-5
ANT-20/ANT-20E PDH MUX/DEMUX
2.3 Offset measurements
All offsets in the hierarchy stages in the measurement path are measured simultaneously and
displayed.
Display in ppm
2.4 Error measurements (anomalies)
The error measurements are described in the “Specifications” for the mainframe instrument.
The frame alignment signals in all hierarchy stages of the selected path are checked
simultaneously.
2.5 Alarm detection (defects)
The detected alarms are described in the “Specifications” for the mainframe instrument. The
RDI alarms in all hierarchy stages of the selected path are checked simultaneously.
2.6 Evaluation of test signals for bit error measurements
2.6.1 Internal evaluation
Evaluation:
•in all timeslots (framed pattern to ITU-T O.150/O.151)
•in the selected timeslot
2.6.2 External signal (with option 3035/90.20 only)
Output of a signal with bit rate 34 368 kbit/s (coaxial), 8 448 kbit/s (coaxial) or 2 048 kbit/s
(coaxial or balanced) for external evaluation is alternative or simultaneous with internal
evaluation (see Sec. 2.6.1).
The interfaces for this are described in the “Specifications” for the “STM-1 mapping” options.

S-6 Specifications
PDH MUX/DEMUX ANT-20/ANT-20E
3 Drop&Insert / Through Mode / Block&Replace
Option: BN 3035/90.20
3.1 Functions
This Option provides the following functions for all PDH multiplex options fitted to the ANT-20.
Drop&Insert
Generator and receiver operate independently as mapper and demapper. The signal from a
selected channel is dropped from the receive signal and output to a connector. An external
signal is inserted into the transmit signal.
Fig. S-1 Drop&Insert: Generator and receiver operate independently
An unbalanced digital input and output are provided on the mainframe instrument for dropping
and for inserting tributary signals (see Sec. 3.2.1,Page S-8 and Sec. 3.3.1,Page S-9).
The mainframe instrument is also equipped with a balanced output [13] and input [12] for
dropping and for inserting tributary signals via balanced interfaces.
Through Mode
The received signal is looped through the ANT-20 and re-transmitted by the generator.
The ANT-20 operates in Through Mode as a signal monitor without affecting the signal.
Fig. S-2 Through Mode: Generator and receiver coupled

Specifications S-7
ANT-20/ANT-20E PDH MUX/DEMUX
The looped-through signal can also be jittered using the Jitter Generator options (Jitter
Generator up to 155 or 622 Mbit/s, BN 3035/90.60 to 61). This function is available for all bit
rates fitted to the instrument.
Fig. S-3 Through Mode: Adding jitter to the looped-through signal
Block&Replace
In PDH mode not possible.
3.1.1 Clock generator
Drop&Insert
As specified in the “Specifications” of the mainframe instrument.
Through Mode
In Through Mode, clock generation is always derived from the receive signal clock.
No signal offset is possible in this operating mode (see also the “Specifications” of the
mainframe instrument).
3.1.2 Anomaly insertion
Drop&Insert
As specified in Sec. 1.4,Page S-3.
Through Mode
Anomaly insertion is not possible.
3.1.3 Defect generation
Drop&Insert
As specified in Sec. 1.5,Page S-3.
Through Mode
Defect generation is not possible.

S-8 Specifications
PDH MUX/DEMUX ANT-20/ANT-20E
3.1.4 Measurements
There are no restrictions on measurements (see Sec. 2,Page S-4).
3.2 Signal outputs
3.2.1 AUXILIARY signal output [11], electrical
3.2.2 LINE/AUXILIARY signal output [13], electrical
Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .unbalanced, (coaxial)
Socket type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . BNC
Output impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 Ω
Max. permitted peak spurious input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 5 V
Interface Bit rate (Mbit/s) Line code Output voltage
E4 139.264 CMI ±0.5 V
DS3 44.736 B3ZS ±1.0 V
E3 34.368 HDB3
E2 8.448 HDB3 ±2.37 V
E1 2.048 HDB3
DS1 1.544 B8ZS
The bit rates depend on the mapping options fitted.
Table S-5 Specifications of the AUXILIARY signal output [11], electrical
Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .balanced
Socket type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Lemo SA
(Bantam)
Output impedance
2.048 Mbit/s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Ω
1.544 Mbit/s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Ω
Max. permitted peak spurious input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 5 V

Specifications S-9
ANT-20/ANT-20E PDH MUX/DEMUX
The balanced output is used as a LINE or as an AUXILIARY output.
3.3 Signal inputs
3.3.1 AUXILIARY signal input [10], electrical
LOS (Loss of Signal) status display
LED lights up if the signal input is active but no signal is present.
Interface Bit rate (Mbit/s) Line code Output voltage
E1 2.048 HDB3 ±3.0 V
DS1 1.544 B8ZS DSX-1 compatible
The bit rates depend on the mapping options fitted.
Table S-6 Specifications of the LINE/AUXILIARY signal output [13], electrical
Connector. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . unbalanced, (coaxial)
Socket type. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .BNC
Input impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75Ω
Max. permitted frequency offset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 500 ppm
Input voltage range. . . . . . . . . . . . . . . . . . . . . . . . . . .0 dB attenuation referred to nominal level
Max. permitted peak input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 5 V
Interface Bit rate (Mbit/s) Line code Input voltage
E4 139.264 CMI 1.0 V ±10 %
DS3 44.736 B3ZS 1.0 V ±10 %
E3 34.368 HDB3
E2 8.448 HDB3 2.37 V ±10 %
E1 2.048 HDB3
DS1 1.544 B8ZS
The bit rates depend on the mapping options fitted.
Table S-7 Specifications of the AUXILIARY signal input [10], electrical

S-10 Specifications
PDH MUX/DEMUX ANT-20/ANT-20E
3.3.2 LINE/AUXILIARY signal input [12], electrical
LOS (Loss of Signal) status display
LED lights up if the signal input is active but no signal is present.
The balanced input is used as a LINE or as an AUXILIARY input.
Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .balanced
Socket type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Lemo SA
(Bantam)
Input impedance
2.048 Mbit/s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120 Ω
1.544 Mbit/s. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100 Ω
Max. permitted frequency offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . ± 500 ppm
Max. number of consecutive zeros for line code = AMI. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Max. permitted peak input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ± 5 V
Interface Bit rate (Mbit/s) Line code Input voltage
E1 2.048 HDB3 3.0 V ±10 %
DS1 1.544 B8ZS
The bit rates depend on the mapping options fitted.
Table S-8 Specifications of the LINE/AUXILIARY signal input [12], electrical
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