Agilent 37718A Users Guide

HP 37718A Communications Performance Analyzer
User’s Guide PDH/SDH Operation
Copyright Hewlett­Packard Ltd.1998
All rights reserved. Reproduction, adaption, or translation without prior written permission is prohibited, except as allowed under the copyright laws.
HP Part No. 37718-90003
First edition, 09/98 Printed in U.K.
Warranty
The information contained in this document is subject to change without notice.
Hewlett-Packardmakes no warranty of any kindwithregardto this material, including, but not limited to, the implied warranties or merchantability and fitness for a particular purpose.
Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequentialdamages in connection with the furnishing, performance, or use of this material.
WARNING
WarningSymbols Used on the Product
!
The product is marked with this symbol when the usershould refer to the instruction manual in order to protect the apparatus against damage.
The product is marked with this symbol to indicate that hazardous voltages are present
The product is marked with this symbol to indicate that a laser is fitted. The user should refer tothe laser safety information in the Calibration Manual.
Hewlett-Packard Limited Telecommunications Networks Test Division South Queensferry West Lothian, Scotland EH30 9TG
User’s Guide PDH/SDH Operation
HP 37718A Communications Performance Analyzer
About This Book
This book tells you how to select the features that you want to use for your test.
The selections available are presented in the following groups:
Transmit and receive interfaces
Test features, for example, the addition of errors and alarms to the test signal
Measurements including test timing
Storing, logging and printing results with general printer information
Using instrument and disk storage
Using the “Other” features.
The selections available will depend on the options fitted to your instrument. The examples given in this book cover all options and therefore may include selections which are not available on your instrument.
iv
Contents
1 Setting the Interfaces
Setting PDH Transmit Interface 10 Setting SDH Transmit Interface 12 Setting SDH THRU Mode 15 Using Smart Test 17 Setting PDH Receive Interface 19 Setting SDH Receive Interface 21
2 Selecting Test Features
Using Transmit Overhead Setup 24 Using Receive Overhead Monitor 26 Setting Overhead Trace Messages 28 Generating Overhead Sequences 29 Using Receive Overhead Capture 31 Adding Frequency Offset to SDH Signal 33 Adding Frequency Offset to the PDH Signal 35 Setting up Signaling Bits 36 Setting Transmit Structured Payload/Test Signal 39 Setting Receive Structured Payload/Test Signal 41 Setting Transmit N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal 42 Setting Receive N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal 44 Inserting an External PDH Payload/Test Signal 45 Dropping an External Payload/Test Signal 48 Adding Errors & Alarms at the SDH Interface 51 Adding Errors & Alarms to the PDH Interface/PDH Payload 52 Using FEAC Codes 53
v
Contents
Setting PDH Spare Bits 55 Adding Pointer Adjustments 56 Using Pointer Graph Test Function 63 Stressing Optical Clock Recovery Circuits 65 Generating Automatic Protection Switch Messages 66 Inserting & Dropping Data Communications Channel 67
3 Making Measurements
Using Overhead BER Test Function 70 Test Timing 71 Making SDH Analysis Measurements 72 Making PDH Analysis Measurements 73 Measuring Frequency 74 Measuring Optical Power 75 Measuring Round Trip Delay 76 Monitoring Signaling Bits 78 Measuring Service Disruption Time 79 Performing an SDH Tributary Scan 82 Performing an SDH Alarm Scan 84 Performing a PDH/DSn Alarm Scan 85
4 Storing, Logging and Printing
Saving Graphics Results to Instrument Store 88 Recalling Stored Graph Results 89 Viewing the Bar Graph Display 91 Viewing the Graphics Error and Alarm Summaries 93
vi
Contents
Logging Graph Displays 95 Logging Results 97 Logging on Demand 100 Logging Results to Parallel (Centronics) Printer 102 Logging Results to HP-IB Printer 103 Logging Results to Internal Printer 104 Logging Results to RS-232-C Printer 105 Printing Results from Disk 106 Connecting an HP DeskJet Printer to a Parallel Port 107 Changing Internal Printer Paper 108 Cleaning Internal Printer Print Head 111
5 Using Instrument and Disk Storage
Storing Configurations in Instrument Store 114 Titling Configuration in Instrument Store 115 Recalling Configurations from Instrument Store 116 Formatting a Disk 117 Labeling a Disk 118 Managing Files and Directories on Disk 119 Saving Graphics Results to Disk 126 Saving Data Logging to Disk 128 Saving Configurations to Disk 129 Recalling Configuration from Disk 130 Recalling Graphics Results from Disk 131 Copying Configuration from Instrument Store to Disk 132 Copying Configuration from Disk to Instrument Store 134 Copying Graphics Results from Instrument Store to Disk 136
vii
Contents
6 Selecting and Using "Other" Features
Coupling Transmit and Receive Settings 140 Setting Time & Date 141 Enabling Keyboard Lock 142 Enabling Beep on Received Error 143 Suspending Test on Signal Loss 144 Setting Error Threshold Indication 145 Setting Screen Brightness and Color 146 Dumping Display to Disk 147 Running Self Test 149
7 AU-3/TUG-3 Background Patterns
8 ETSI/ANSI Terminology
ETSI/ANSI Conversion and Equivalent Terms 158
viii
1

1 Setting the Interfaces

This chapter tells you how to set the instrument interfaces to match the network being tested.
Setting the Interfaces

Setting PDH Transmit Interface

Description PDH transmit interface settings should match network equipment
settings of Rate, Termination and Line Code and determine the Payload to be tested.
TIP: To set the Transmitter and Receiver to the same interface settings
choose .
OTHER
SETTINGS CONTROL COUPLED
HOW TO: 1 Choose the required SIGNAL rate.
If Option 010 is fitted, rates of 2, 8, 34 and 140 Mb/s are available. If Option 011 is fitted rates of DS1, DS3, 2 Mb/s and 34 Mb/s are available.
2 Choose the required CLOCK SYNC (clock synchronization source). 3 If DS1 or DS3 is chosen, choose the required interface level. 4 If you have chosen 2 Mb/s as the SIGNAL rate, choose the required
TERMINATION. (At all other signal rates the impedance is fixed).
10
Setting the Interfaces
Setting PDH Transmit Interface
5 If you have chosen 2 Mb/s, DS1 or 8 Mb/s as the SIGNAL rate, choose
the required LINE CODE. (At 34 Mb/s, 140 Mb/s and DS3 coding is fixed.)
6 If required, choose the FREQUENCY OFFSET value.
See “Adding Frequency Offset to SDH Signal” page 33.
7 Choose the required PAYLOAD TYPE.
If STRUCTURED is required FRAMED must be chosen. If Structured is chosen the PDH test signal must be set up. See “Setting Transmit Structured Payload/Test Signal” page 39. If you have chosen 2 Mb/s, DS1 or DS3 as the PDH/DSn signal rate, the Framed choice is expanded to provide a menu of framing types.
8 Choose the PATTERN type and the PRBS POLARITY.
11
Setting the Interfaces

Setting SDH Transmit Interface

Setting SDH Transmit Interface
Description SDH transmit interface settings should match the network equipment
settings of Rate, Wavelength and Mapping, determine the payload to be tested and set background conditions to prevent alarms while testing.
TIP: If you wish to set the HP 37718A transmitter and receiver to the same
interface settings choose .
OTHER
SETTINGS CONTROL COUPLED
HOW TO: 1 Make your choice of SIGNAL rate.
If Option106, Dual Wavelengthopticalmodule, isfittedand anoptical rate is chosen, choose the required wavelength (1550) or (1310). If STM-0 is chosen, choose the required interface level. ChooseINTERNALunless THRUMODEis required.If THRU MODE is chosen, see "Setting SDH THRU Mode " page 15.
2 Make your choice of CLOCK synchronization source. The RECEIVE
clock sync choice depends on the SDH Receive Interface choice. EXTERNAL allows a choice of MTS, BITS or 10 MHz clocks.
3 If required choose the FREQUENCY OFFSET value. See “Adding
Frequency Offset to SDH Signal” page 33.
4 Choose FOREGROUND , BACKGROUND
B/G MAPPING
12
MAPPING and type of payload.
F/G MAPPING
Setting the Interfaces
Setting SDH Transmit Interface
Mapping may beselectedfroma pictorial display by moving the cursor to MAPPING and pressing .
SET
Use and to move between AU Layer Selection, TU Layer Selection and Payload Layer Selection. Use and to set the mapping and to set your selection.
SET
5 If TU-2 mapping is chosen, TU CONCATENATION selection is
enabled, choose OFF or the tributary at which the concatenation begins, TU2-2C through TU2-6C. The BACKGROUND, PATTERN IN OTHER TU2’s is fixed at NUMBERED, that is, each TU-2 contains a unique number to allow identification in case of routing problems.
6 If required, choose DS1/2M/34M/DS3/140M OFFSET value. See
“Adding Frequency Offset to SDH Signal” page 33
7 If TU-3, TU-2, TU-12 or TU-11 mapping is chosen, choose the test
tributary CHANNEL, including the STM-1 for an STM-4/STM-16 signal.
8 Choose thepayloadframing under PAYLOADTYPE or TU PAYLOAD.
If STRUCTURED is required FRAMED must be chosen. If STRUCTURED is chosen, the Payload test signal must be set up. See “Setting Transmit Structured Payload/Test Signal” page 39. If INSERT is chosen, see “Inserting an External PDH Payload/Test Signal” page 45. If you have chosen 2 Mb/s, DS1 or DS3 under Mapping, the Framed choice is expanded to provide a menu of framing types.
13
Setting the Interfaces
Setting SDH Transmit Interface
9 If 2Mb/s framing PCM30 orPCM30CRCis chosen, settheCAS ABCD
bit value. See "Setting up Signaling Bits " page 36
10 Choose the PATTERN type and PRBS polarity.
11 Choose the mapping required in the background (non-test) TUG-3s.
Refer to Appendix A for a table of background patterns for AU-3 and TUG-3.
12 If TU-12 mapping is chosen for the test TUG-3, choose the PATTERN
IN OTHER TU-12s.
14
Setting the Interfaces

Setting SDH THRU Mode

Setting SDH THRU Mode
Description THRU mode is used to non-intrusively monitor SDH lines where no
protected monitor points are available. As THRU mode locks some user settings, you must set SIGNAL RATE,
AU rate, AU-3 CHANNEL (if appropriate) before selecting THRU mode. The entire frame can be errorred at a user defined rate if PAYLOAD
OVERWRITE and SOH+POH CHANNEL OVERWRITE are both set to OFF. If either overwrite is enabled the ENTIRE FRAME ERROR RATE function is disabled.
STM-0, STM-1
You can substitute a new payload, Section overhead (SOH) and Path overhead (POH) in the received STM-0/1 signal for testing.
STM-4, STM-16
The overhead and payload may be overwritten for AU-4 and AU3. PAYLOAD OVERWRITE is not available for AU-4-4c or AU-4-16c. SOH overwrite is available for AU-4-4C and AU-4-16c.
HOW TO:
1 Make the required SIGNAL RATE, MAPPING and CHANNEL
choices on the SDH and displays, See "Setting SDH Transmit Interface " page 12 and "Setting SDH Receive Interface " page 21.
TRANSMIT
RECEIVE
15
Setting the Interfaces
Setting SDH THRU Mode
2 Make the PAYLOAD OVERWRITE choice required.
If AU-4,AU-3, TU-3,TU-2or TU-12 is chosen,theB1, B2 andB3BIPs are recalculated before transmission and the Mapping, Selected TU, TU Payload, Pattern, Tributary Offset and Pattern in other TU’s settings are displayed. To choose the settings in these, See "Setting SDH Transmit Interface " page 12, steps 4 through 10.
3 Make the SOH+POH OVERWRITE choice required.
You can only modify those overheadbytesavailableunder
SDH TEST FUNCTION SDH
: Errors & Alarms, Sequences,
TRANSMIT
Overhead BER, APS Messages and DCC Insert. The B1, B2 and B3 BIPs are recalculated before transmission.
16
Setting the Interfaces

Using Smart Test

Using Smart Test
Description The SmartTest functioncanhelp speed-up configuring the instrument in
two ways. 1 A Smartsetup feature that will attempt to configure the instrument
to receive the incoming signal.
2 A series of “links” that provide quick access to some of the most
frequently used features of the instrument. Note that these tests are run with the instrument in its current configuration, no attempt is made to set the instrument to the requirements of the test.
Smartsetup can help the user by attempting to identify the incoming signal structure and detect mixed payload signal structures.
HOW TO USE SMARTSETUP:
1 Connect the HP 37718A to the network and choose if necessary the
required SDH interface on the HP 37718A(Smartsetup will select PDH or SDH/SONET, but can not select between SDH and SONET).
2 Press .
The display will show the Smart Test menu above.
3 Press either or .
SMART TEST
RECEIVE
SET
SELECT
17
Setting the Interfaces
Using Smart Test
4 In SDH mode the incoming signal will be identified on the top line of
thedisplay,andunder this thepayload mappings,theJ1 TraceandC2 byte indicators are displayed on the bottom lines.
5 Use the and keys to display the J1Traceinformationforeach
AUG. When the AUG of interest has been identified choose either
VIEW PAYLOAD PRBS SEARCH
or .
6 Choosing will identify and display the payload
VIEW PAYLOAD
mapping of the TUG structured signal, as shown below. Choose the required tributary using and .
7 There are four choices available at this point:
SETUP RX TROUBLE SCAN
tributary, exitstothe displayandstarts
which sets the receiver to receive the selected tributary.
which sets the receiver to receive the selected
RESULTS
TROUBLE SCAN
gating.
VIEW LABELS
which displaystheC2/V5/J1/J2 trace information for
the selected tributary.
TOP LEVEL
which returns the display to the AUG selection window.
8 Choosing at Step 5 will prompt you for additional
PRBS SEARCH
information about patterns and which mapping to search. When the required data has been entered press .
GO
9 When the search is complete a tributary display appears, with any
tributariescontainingthe required PRBSindicated with a“P”. Choose the required tributary using and .
18
Setting the Interfaces

Setting PDH Receive Interface

Setting PDH Receive Interface
Description PDH Receive interface settings should match the network equipment
settings of Rate, Termination and Line Code and determine the Payload to be tested.
TIP: To set the transmitter and receiver to the same interface settings choose
OTHER
SETTINGS CONTROL COUPLED
.
HOW TO: 1 Choose the required SIGNAL rate.
2 If you have chosen 2 Mb/s as the SIGNAL rate, choose the required
TERMINATION. (At all other rates the impedance is fixed.)
3 If you have chosen 2 Mb/s, DS1 or 8 Mb/s as the SIGNAL rate, choose
the required LINE CODE. (At 34Mb/s, 140 Mb/s and DS3 coding is fixed.)
4 If you are measuring at the networkequipmentmonitorpoint,set the
LEVEL field to MONITOR. In this case the received signal will be 20 to 30 dB below the normal level. Choose the GAIN required to return the received signal to normal. Choose EQUALIZATION to compensate for cable losses if required.
19
Setting the Interfaces
Setting PDH Receive Interface
5 Choose the PAYLOAD TYPE.
If STRUCTURED is required FRAMED must be chosen. If STRUCTURED is chosen, the PDH test signal must be set up. See “Setting Transmit Structured Payload/Test Signal” page 39. If you chose 2 Mb/s, DS1 or DS3 as the PDH/DSn SIGNAL rate, the FRAMED choice is expanded to provide a menu of framing types.
6 Choose the PATTERN type and the PRBS POLARITY required.
20
Setting the Interfaces

Setting SDH Receive Interface

Setting SDH Receive Interface
Description SDH Receive interface settings should match the network equipment
settings of Rate and Mapping, and determine the payload to be tested.
TIP: If you wish to set the HP 37718A transmitter and receiver to the same
interface settings, choose .
OTHER
SETTINGS CONTROL COUPLED
HOW TO: 1 Choose the required SIGNAL source.
If STM-0 or STM-1 electrical is chosen, choose the required LEVEL. If the LEVEL chosen is MONITOR choose the required GAIN.
2 Choose mapping and type of payload. 3 IfTU-2mapping ischosen,and CONCATENATIONisenabled, choose
the tributary at which the concatenation begins. If TU-2, TU-3, TU-12 or TU11 mapping is chosen, choose the test tributary under CHANNEL.
4 Choose thepayloadframing under PAYLOAD TYPE or TUPAYLOAD.
If STRUCTURED is required FRAMED must be chosen. IfSTRUCTUREDis chosenthePayloadtest signal mustbe set up.See “Setting Receive Structured Payload/Test Signal” page 41. If DROP is chosen, see “Dropping an External Payload/Test Signal” page 48.
5 Choose the PATTERN type and PRBS polarity.
21
Setting the Interfaces
Setting SDH Receive Interface
22
2

2 Selecting Test Features

Selecting Test Features

Using Transmit Overhead Setup

Description You can set an overhead byte to a known static state to aid
troubleshooting, for example to quickly check for "stuck bits" in path overhead bytes. Section Overhead, Path Overhead, Trace Messages and Labels can be set using this feature.
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12.
2 Choose the type of overhead to SETUP.
If STM-4 OPT or STM-16 OPT is chosen as the SDH interface, choose the STM-1 you wish to set up. DEFAULT - Use to set all overhead bytes to the standard values defined by ITU-T. If a test function is active then the overhead byte value is determined by the choices made in the Test Function. For example if APS Messages is chosen, the K1K2 value is determined by the APS Messages setup.
24
Selecting Test Features
Using Transmit Overhead Setup
3 If SOH (Section Overhead) is chosen, choose the COLUMN to be
displayed. Many bytes in COLS 2,5,8 and 3,6,9 are unlabeled as the other overhead functions have not yet been defined. If ALL COLUMNS is chosen, the hexadecimal value of all 81 bytes of the STM-1 sectionoverheadselectedare displayed (all 324 bytes ofan STM-4 or 1,296 bytes of an STM-16 are displayed 81 bytes at a time by selecting each STM-1 in turn). The value of the bytes can be set
using .
DECREASE DIGIT INCREASE DIGIT
If BYTE NAMES is chosen, the labels for the ALL COLUMNS overhead bytes are displayed.
4 If POH (Path Overhead) is chosen, choose the TYPE of overhead
within STM-1 under test to be setup. J1 and J2 bytes can be set under Path Overhead or Trace Messages. H4 bytehasa choice of sequences forTU-12,TU11 and TU-2 mapping:
Full Sequence - 48 byte binary sequence. Reduced Sequence - Binary count sequence of 0 to 3 i.e. 111111(00
to 11). COC1 Sequence - Binary count sequence of 0 to 3 i.e. 110000(00 to
11).
5 If TRACE MESSAGES is chosen, see "Setting Overhead Trace
Messages " page 28.
NOTE Any bit of an overhead byte which is displayed as x or s cannot be set at
any time. All other bits can be set to 0 or 1.
TIP: You can set all overhead bytes to the default state by selecting SETUP
DEFAULT
.
You can set all overhead bytes and test functions to the default state by recalling Stored Settings [0] on the display.
OTHER
25
Selecting Test Features

Using Receive Overhead Monitor

Using Receive Overhead Monitor
Description When first connecting to a SDH network, a start up confidence check can
be made by viewing the behavior of all the overhead bytes. If the SDH network shows alarm indications, some diagnosis of the problem may be gained from viewing all the overhead bytes.The OVERHEAD MONITOR display is updated once per second (once per 8000 frames) approximately.
A snapshot of the received overhead can be logged to the chosen logging device. See "Logging on Demand " page 100.
HOW TO: 1 Setupthe receiveSDH interfaceand payloadas required.See“Setting
SDH Receive Interface” page 21.
2 Choose the type of overhead to MONITOR. 3 If SOH (Section Overhead) is chosen, choose the STM-1 number and
COLUMN to be displayed. Many bytes in COLS 2,5,8 and 3,6,9 are unlabeled because the other overhead functions have not yet been defined. If ALL COLUMNS is chosen, the hexadecimal value of all 81 bytes of section overheadis displayed (all324bytes of anSTM-4or 1,296 bytes of an STM-16aredisplayed81 bytes at a time by selecting eachSTM­1 in turn).The value of the bytes can be set using
INCREASE DIGIT
26
.
DECREASE DIGIT
Selecting Test Features
Using Receive Overhead Monitor
If BYTE NAMES is chosen, the labels for the ALL COLUMNS overhead bytes are displayed.
4 If POH (Path Overhead) is chosen, choose the source of the overhead
VC-4, VC-3, VC-2, VC-12 or VC-11. J1 and J2 bytes can be monitored under Path Overhead or Trace Messages
5 If TRACE MESSAGES is chosen, you can monitor a data message to
verify portions of the network. If the 16 byte CRC7 message structure is detected, the 15 characters within the message are displayed. If the CRC7 structure is not detected in J1, the 64 byte message format is assumed and displayed. If the CRC7 structure is not detected for J0 or J2, all 16 bytes are displayed.
6 If LABELS is chosen, the S1 sync status, HP path label (C2) and the
LP Path label (V5) are monitored.
7 If APS MESSAGES is chosen, choose the TOPOLOGY,
(G.783) or (G.841). The K1 and K2 bits are monitored.
RING
LINEAR
TIP: If any abnormal behavior is observed on a particular path or section
overhead byte, or an associated group of bytes (3XA1,3XA2; D1 - D3), the
RECEIVE
TEST FUNCTION
display of can be
OVERHEAD CAPTURE
used to "Zoom" in on the suspect byte or bytes on a frame by frame basis. See "Using Receive Overhead Capture " page 31.
27
Selecting Test Features

Setting Overhead Trace Messages

Setting Overhead Trace Messages
Description You can insert a data message to verify portions of the network:
J0 verifies the regenerator section overhead. J1 verifies the VC-3 or VC-4 path connection. J2 verifies the VC-2, VC-12 or VC-11 path connection.
HOW TO: 1 Choose the message for insertion in the chosen trace channel.
ChoosingLABELSin TRACE MESSAGESallows the settingof the S1 SYNC STATUS, HP PATH LABEL (C2) and LP PATH LABEL (V5).
28
Selecting Test Features

Generating Overhead Sequences

Generating Overhead Sequences
Description You may insert a pattern into a functional group of overhead bytes for
testing or troubleshooting purposes.
HOW TO: 1 Set up theSDHtransmit interface and payload required. See“Setting
SDH Transmit Interface” page 12.
2 Choose the type of sequence required.
SINGLE RUN - runs the sequence once and then stops. REPEAT RUN - runs the sequence repeatedly until STOPPED is chosen.
3 Choose the overhead type as required.
RSOH- Regenerator Section Overhead MSOH- Multiplexer Section Overhead POH - Path Overhead
4 Choose the byte or bytes of overhead required. 5 Set up the required number of data patterns and the number of
frames in which each data pattern should appear. Your sequenceisderived fromup to5blocks ofhexadecimal data.Each block can be transmitted in up to 64,000 frames. The data and the number of frames are set using
INCREASE DIGIT
.
DECREASE DIGIT
29
Selecting Test Features
Generating Overhead Sequences
6 Start the sequence by choosing .
START
NOTE When youstart the sequenceillustrated,one Out ofFramealarm andone
Loss of Frame alarm should occur every eight seconds.
30
Selecting Test Features

Using Receive Overhead Capture

Using Receive Overhead Capture
Description Regenerator section, Multiplexer section and Path overhead provide
network support functions, responding dynamically to network conditions and needs. It is therefore useful to capture overhead activity on a frame by frame basis.
The Overhead Capture display can be logged to the chosen logging device. See "Logging on Demand " page 100.
HOW TO: 1 Setupthe receiveSDH interfaceand payloadas required.See“Setting
SDH Receive Interface” page 21.
2 Choose the overhead type as required.
RSOH- Regenerator Section Overhead MSOH- Multiplexer Section Overhead
POH- Path Overhead 3 Choose the Byte or bytes of overhead to be captured. Choose the TRIGGER to determine the start point of the capture.
- starts immediately the capture is initiated. Can be used to
OFF
provide a frame by frame monitor of the chosen byte or bytes.
-captures activity after your specified overhead state has occurred.
ON
Can be used for transient detection from a specified expected state.
31
Selecting Test Features
Using Receive Overhead Capture
ON NOT
- captures activityafterthe first occurrence of adeviationfrom your specified overhead state. Can be used for transient detection from a specified expected state.
4 Up to 16 records of overhead state are provided. Each record will
represent between 1 and 64,000 frames. A capture is started by pressing CAPTURE and terminates when up to 16 records
START
havebeen captured.Thecapture canbe terminatedearlierby pressing CAPTURE .
STOP
32
Selecting Test Features

Adding Frequency Offset to SDH Signal

Adding Frequency Offset to SDH Signal
Description Frequency offset can be added to the SDH interface rate signal and to
the payload signal.
HOW TO: SDH Line Rate Offset
1 Choose the amount of frequency offset required.
You can set the Frequency Offset in the range -999 ppm to +999 ppm in1ppm stepsusing and . The amount of applied Frequency Offset can be varied while measurements are taking place. If the valueofthe SDH line rate offset chosenissufficient to cause the maximumstuffrate to beexceeded, the asynchronouspayload is offset to prevent bit errors occurring and the maximum stuff rate is maintained. WhenFloatingByte 2 Mb/sischosen, in conjunction with SDH linerateoffset, the chosen tributarywill be offset astheline rate is offset. (No pointer movements).
Tributary Offset ±100 ppm
1 Choose the amount of tributary offset required.
You can set the Offset in the range -100 ppm to +100 ppm in 1 ppm steps using and . The amount of applied Frequency Offset can be varied while measurements are taking place.
DECREASE DIGIT INCREASE DIGIT
DECREASE DIGIT INCREASE DIGIT
33
Selecting Test Features
Adding Frequency Offset to SDH Signal
Tributary offset affects the stuff rate but does not cause pointer movements and can be used to test mapping jitter. If the combined value ofSDH line rateoffsetand tributary offsetchosenis sufficientto cause the maximum stuff rate to be exceeded the payload is offset to prevent bit errors occurring and the maximum stuff rate is maintained.
34
Selecting Test Features

Adding Frequency Offset to the PDH Signal

Adding Frequency Offset to the PDH Signal
Description You can add frequency offset to the interface PDH SIGNAL at all rates.
Frequency Offset can be added at preset ITU values or as User defined values in the range ±100 ppm. The preset values change with the SIGNAL rate chosen as shown:
DS-1 (1.544 Mb/s) + 32 ppm 32 ppm 2 Mb/s (E1) + 50 ppm 50 ppm 8 Mb/s (E2) +30 ppm 30 ppm 34 Mb/s (E3) + 20 ppm 20 ppm DS-3 (44.736 Mb/s) + 20 ppm 20 ppm 140 Mb/s (E4) +15 ppm 15 ppm
HOW TO: 1 Choose the FREQUENCY OFFSET required.
2 If you choose USER OFFSET, you can set the frequency offset to be
between -100 ppm and +100 ppm in 1 ppm steps. Select the field immediately below USER OFFSET and use
DECREASE DIGIT INCREASE DIGIT
frequency offset.(The amount of frequency offset can be varied while measurements are taking place.)
, , and to set the
35
Selecting Test Features

Setting up Signaling Bits

Setting up Signaling Bits
Description When transmitting 2.048 Mb/s signals with timeslot-16 CAS (PCM30 or
PCM30CRC) multiframing the state of A,B,C,D signaling bits can be set. The signaling bits of all timeslots are set to the user-defined 4 bit value.
When transmitting a DS1 framed, structured signal the values of the A,B signaling bits for D4 and SLC-96 payloads, and A,B,C,D signaling bits for ESF payloads can be defined.
HOW TO Transmit a 2 Mb/s signal with user-defined signaling bits
PDH Operation
1 Choose on the display. 2 Choose SIGNAL and PAYLOAD TYPE or
PCM30CRC
PDH/DSn
2 Mb/s PCM30
on the display.
TRANSMIT
MAIN SETTINGS
3 If UNSTRUCTURED is chosen set the 2M CAS ABCD bits value on
the display.
MAIN SETTINGS
If STRUCTURED is chosen set the 2M CAS ABCD bits value on the
STRUCTURED SETTINGS
display.
36
Selecting Test Features
Setting up Signaling Bits
SDH Operation
1 Choose on the display
SDH
2 Choose MAPPING or and TU
PAYLOAD to or onthe display.
PCM30 PCM30CRC
TRANSMIT
ASYNC 2Mb/s FL BYTE 2Mb/s
MAIN SETTINGS
3 If UNSTRUCTURED is chosen set the 2M CAS ABCD bits value on
the display.
MAIN SETTINGS
If STRUCTURED is chosen set the 2M CAS ABCD bits value on the
STRUCTURED SETTINGS
display.
HOW TO Transmit a DS1 payload signal with user-defined signaling bits

PDH Operation

1 Choose on the display.
PDH/DSn
TRANSMIT
37
Selecting Test Features
Setting up Signaling Bits
2 Choose SIGNAL or , and PAYLOAD TYPE
on the display
MAIN SETTINGS
3 Choose TEST SIGNAL or on the
SETTINGS
DS1 DS3
56 kb/s Nx56 kb/s
display.
STRUCTURED
STRUCTURED
4 Set the A,B bits (for D4 and SLC-96) and A,B,C,D bits (for ESF) as
required.

SDH Operation

1 Choose on the display.
SDH
2 Choose MAPPING or and TU PAYLOAD
STRUCTURED MAIN SETTINGS
on the display
3 Choose TEST SIGNAL or on the
SETTINGS
display .
TRANSMIT
ASYNC DS1
56 kb/s Nx56 kb/s
DS3
STRUCTURED
4 Set the A,B bits (for D4 and SLC-96) and A,B,C,D bits (for ESF) as
required.
38
Selecting Test Features

Setting Transmit Structured Payload/Test Signal

Setting Transmit Structured Payload/Test Signal
Description Structured PDH Payload/Test Signal settings determine the SDH
payload or the PDH test signal to be tested and set any background (non test) conditions to prevent alarms while testing.
TIP: If you wish to set the HP 37718A transmitter and receiver to the same
Payload settings, choose .
OTHER
SETTINGS CONTROL COUPLED
HOW TO: 1 Choose the required TEST SIGNAL rate. If Nx64 kb/s is chosen, see
"Setting Transmit N x 64 kb/s/N x 56 kb/s Structured Payload/Test
Signal " page 42.
2 Choose the PAYLOAD framing pattern.
If the TEST SIGNAL chosen was 2Mb/s, the choice is added to PAYLOAD menu. See "Inserting an External PDH Payload/ Test Signal " page 45.
3 Choosethetest tributaryin the structuredpayload, under34Mb, 8Mb,
2Mb, 64 kb/s or DS2, DS1.
4 Choose the PATTERN type and PRBS POLARITY. 5 Choose the B/G PATTERN.
The B/G PATTERN in the non test 64 kb/s timeslots is fixed as NUMBERED,that is,each timeslotcontains auniquenumber toallow identification in case of routing problems.
INSERT 2 Mb/s
39
Selecting Test Features
Setting Transmit Structured Payload/Test Signal

Signaling

6 If a 2 Mb/s PAYLOAD with PCM30 or PCM30CRC framing,or 56 kb/s
or Nx56kb/s Test Signal is chosen. See, "Setting up Signaling Bits " page 36.
40
Selecting Test Features

Setting Receive Structured Payload/Test Signal

Setting Receive StructuredPayload/Test Signal
Description Structured PDH Payload/Test Signal settings determine the SDH
payload or the PDH test signal to be tested.
TIP: If you wish to set the HP 37718A transmitter and receiver to the same
Payload settings, choose .
OTHER
STORED SETTINGS COUPLED
HOW TO: 1 Choose the required Test Signal rate. If N x 64 kb/s or N x 56 kb/s is
chosen, see "Setting Receive N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal " page 44.
2 Choose the Framing pattern of the PAYLOAD.
If 2 Mb/s TEST SIGNAL is chosen, is added to the menu. See "Dropping an External Payload/Test Signal " page 48.
3 Choose the test tributary within the structured payload,under34Mb,
8Mb, 2Mb, 64 kb or DS2, DS1.
4 Choose the PATTERN type and PRBS polarity.
DROP 2 Mb/s
41
Selecting Test Features

Setting TransmitNx64kb/s/N x 56 kb/s Structured Payload/Test Signal

Setting Transmit N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal
Description Wideband services such as high speed data links and LAN
interconnection require a bandwidth greater than 56/64 kb/s but less than DS1/2 Mb/s for example 128 kb/s or 384 kb/s. These wideband signals are sent in a DS1/2 Mb/s frame by sharing the signal between multiple timeslots. N x 64kb/s/N x 56 kb/s structured payload allows a test pattern to be inserted across a number of timeslots even if the chosen timeslots are non-contiguous.
HOW TO: 1 Choose the required Test Signal rate.
2 Choose the Framing pattern of the 2M or DS1 PAYLOAD. 3 Choose the test timeslots within the structured payload using
DESELECT ALL DESELECT SELECT
timeslot is selected, an * marks the chosen timeslot. In the example above Timeslots 3, 5, 9, 25, 26, 27 are selected for test.
4 Choose the PATTERN type and PRBS polarity. 5 Choose the B/G PATTERN. 6 The B/G PATTERN in the non-test 64 kb/s timeslots is fixed as
NUMBERED, that is, each timeslot contains a unique identification number.
42
and softkeys. As each
Selecting Test Features
Setting TransmitNx64kb/s/N x 56 kb/s Structured Payload/Test Signal

Signaling

7 If a 2 Mb/s PAYLOAD with PCM30 or PCM30CRC framing,or 56 kb/s
or Nx56kb/s Test Signal is chosen. See, "Setting up Signaling Bits " page 36.
43
Selecting Test Features

Setting Receive N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal

Setting Receive N x 64 kb/s/N x 56 kb/s Structured Payload/Test Signal
Description Wideband services such as high speed data links and LAN
interconnection require a bandwidth greater than 56/64 kb/s but less than DS1/2 Mb/s e.g. 128 kb/s or 384 kb/s. These wideband signals are sent in a ds1/2 Mb/s frame by sharing the signal between multiple timeslots. N x 64kb/s andNx56kb/sstructured payload/test signal allows the test Timeslots to be chosen for error measurement even when the Timeslots are non contiguous.
HOW TO: 1 Choose the required Test Signal rate.
2 Choose the Framing pattern of the 2M or DS1 PAYLOAD. 3 Choose the test timeslots within the structured payload using
DESELECT ALL DESELECT SELECT
timeslot is chosen an * marks the chosen timeslot. In the example above Timeslots 3, 5, 9, 25, 26, 27 are chosen for test.
4 Choose the PATTERN type and PRBS polarity.
44
and softkeys. As each
Selecting Test Features

Inserting an External PDH Payload/Test Signal

Inserting an External PDH Payload/Test Signal
Description Depending on the 37718Aoptionfitted, you can insert a PDH signal from
external equipment into the SDH signal, or you can insert 2 Mb/s or DS1 into the structured PDH signal, as shown in the table below. 140Mb/s, 34Mb/s, DS3 and 34 Mb/s can only be inserted if SDH is chosen as the receive interface. 2 Mb/s or DS1 can be inserted from a structured or non-structured SDH payload and from a structured PDH signal.
RATE Availability Option
140 Mb/s SDH Only 010 Only DS3 SDH & SONET 011 Only 34Mb/s SDH & SONET 010 and 011 2Mb/s PDH, SDH & SONET 010 and 011 DS1 PDH, SDH & SONET 011 Only

HOW TO: Insert 34 Mb/s, DS3 & 140 Mb/s

1 Connect the external payload to the 75 IN port of the PDH/DSn
receive module.
2 Setupthe requiredtransmit SDHinterface, andchoose TUPAYLOAD
INSERT 140 Mb/s
, or as required.
INSERT 34 Mb/s
INSERT DS3
45
Selecting Test Features
Inserting an External PDH Payload/Test Signal

Insert 2 Mb/s or DS1 (Unstructured SDH Payload)

1 Connect the external payload to the MUX port of the PDH Transmit
module. If 2 Mb/s connect to 75MUX port. If DS1 connect to 100Ω MUX port.
2 Set up the required transmit SDH interface, and choose TU12
MAPPING or TU11 MAPPING and TU PAYLOAD or
INSERT DS1
.
INSERT 2 Mb/s

Insert 2 Mb/s or DS1 (Structured SDH Payload or Structured PDH)

1 Connect the external payload to the MUX port of the PDH Transmit
module. If 2 Mb/s connect to 75MUX port. If DS1 connect to 100Ω MUX port.
46
Selecting Test Features
Inserting an External PDH Payload/Test Signal

Structured SDH Payload

2 Set up the required transmit SDH interface. See "Setting SDH
Transmit Interface " page 12.
3 Set up the SDH structured payload. See "Setting Transmit
Structured Payload/Test Signal " page 39.
4 Choose 2M PAYLOAD/DS1 PAYLOAD or
INSERT DS1
.
INSERT 2 Mb/s
5 Choose the LINE CODE.

Structured PDH

6 Set up, the required transmit PDH interface, See "Setting PDH
Transmit Interface " page 10.
7 Set up the PDH Test Signal interface. See "Setting Transmit
Structured Payload/Test Signal " page 39
8 Choose 2M PAYLOAD/DS1 PAYLOAD or
INSERT DS1
.
INSERT 2 Mb/s
9 Choose the LINE CODE.
47
Selecting Test Features

Dropping an External Payload/Test Signal

Dropping an External Payload/Test Signal
Description Depending on the 37718A option fitted, you can drop a PDH signal from
the received payload or drop 2 Mb/s or DS1 from the structured PDH signal to external equipment as shown in the table below. 140Mb/s, 34Mb/s, DS3 and 34 Mb/s can only be dropped if SDH is chosen as the receive interface. 2 Mb/s or DS1 can be dropped from a structured or non­structured SDH payload and from a structured PDH signal.
RATE Availability Option
140 Mb/s SDH Only 010 Only DS3 SDH & SONET 011 Only 34Mb/s SDH & SONET 010 and 011 2Mb/s PDH, SDH & SONET 010 and 011 DS1 PDH, SDH & SONET 011 Only

HOW TO: Drop 34 Mb/s, DS3 & 140 Mb/s

1 Connect the 75 OUT port of the PDH Tx module to the external
equipment.
48
Selecting Test Features
Dropping an External Payload/Test Signal
2 Set up the receive SDH interface, and choose TU PAYLOAD
DROP 140 Mb/s DROP 34 Mb/s
If is chosen, choose the DS3 output level.
DROP DS3
, or .
DROP DS3

Drop 2 Mb/s /DS1 (Unstructured SDH Payload)

1 Connect the DEMUX port of the PDH module to the external
equipment.
2 Set up the required receive SDH interface, and choose TU12
MAPPING or TU11 MAPPING and TU PAYLOAD or
DROP DS1
.
DROP 2 Mb/s
3 Choose the required LINE CODE.
49
Selecting Test Features
Dropping an External Payload/Test Signal

Drop 2 Mb/s/DS1 (Structured SDH Payload or Structured PDH

1 Connect the DEMUX port of the PDH module to the external
equipment. If 2 Mb/s connect to 75DEMUX port. If DS1 connect to 100Ω DEMUX port.

Structured SDH Payload

2 Set up the required receive SDH interface.See "Setting SDH Receive
Interface " page 21.
3 Set up the SDH structured payload. See "Setting Receive Structured
Payload/Test Signal " page 41.
4 Choose 2M PAYLOAD/DS1 PAYLOAD or .
DROP 2 Mb/s
DROP DS1
5 Choose the LINE CODE.

Structured PDH

6 Set up,the required receivePDH interface, See "SettingPDHReceive
Interface " page 19.
7 SetupthePDHTestSignal interface.See "Setting ReceiveStructured
Payload/Test Signal " page 41
8 Choose 2M PAYLOAD/DS1 PAYLOAD or .
DROP 2 Mb/s
DROP DS1
9 Choose the LINE CODE.
50
Selecting Test Features

Adding Errors & Alarms at the SDH Interface

Adding Errors & Alarms at the SDH Interface
Description Errors and alarms can be added to the SDH interface signal during
testing.
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12.
2 Choose the ERROR ADD TYPE and RATE required.
Errors can be added at preset rates and at USER programmable rate. With theexceptionof ENTIRE FRAME and A1A2FRAME,errors can be added at ERROR ALL rate. If B2 BIP errors are chosen errors can be added to trigger an MSP THRESHOLD.This takes the form ofN errors in T timeperiod. N and T are both selectable.
3 Choose the ALARM TYPE
Errors and Alarms can be added at the same time.
51
Selecting Test Features

Adding Errors & Alarms to the PDH Interface/PDH Payload

Adding Errors & Alarms to the PDH Interface/ PDH Payload
Description Errors and alarms can be added to the PDH interface/payload signal
during testing.
HOW TO: 1 If SDH interface is chosen, set up the SDH transmit interface and
payload required. See “Setting SDH Transmit Interface” page 12. If PDH interface is chosen, set up the PDH interface and payload required. See “Setting PDH Transmit Interface” page 10.
2 Choose the ERROR ADD TYPE and RATE on the Transmitter
TEST FUNCTION
The RATEcan be selected from afixedvalue or is userprogrammable. If you select USER PROGRAM you can select the error rate before enabling the errors. This feature is useful for error threshold testing.
3 Choose the ALARM TYPE.
Errors and Alarms can be added at the same time.
52
display.
Selecting Test Features

Using FEAC Codes

Using FEAC Codes
NOTE FEAC codes are only available if Option 011 is fitted.
Description The third C-Bit in subframe 1 is used as a FEAC channel, where alarm
or status information from the far-end terminal can be sent back to the near-end terminal. The channel is also used to initiate DS3 and DS1 line loopbacks at the far-end terminal from the near-end terminal.
The codes are six digits long and are embedded in a 16 bit code word; the format is 0XXXXXX011111111. There are two types of code, Loopback and Alarm Status. Loopback provides a choice of two DS1 messages and two DS3 Messages. The DS1 Messages can be sent in ALL DS1 channels or in a SINGLE channel. The message can be repeated up to 15 times. Alarm Status provides 13 preset codes and a USER programmable code function. These codes can be transmitted continuously or in bursts.
The new code is transmitted by choosing or .

HOW TO: Transmit an FEAC code

1 Choose SIGNAL and PAYLOAD TYPE on the
MAIN SETTINGS
DS3 CBIT
display.
BURST ON
TRANSMIT
53
Selecting Test Features
Using FEAC Codes
2 Choose and ALARM TYPE .
TRANSMIT
TEST FUNCTION DS3 FEAC
When a FEAC code is not being transmitted, an all ones pattern is transmitted.
3 Choose the FEAC CODE TYPE. 4 Choose the MESSAGE from the choices displayed.
If you chose a DS1 message an additional field to the right of the DS1 MESSAGE is displayed. Position the cursor on this field and choose
or .
ALL
If youchoose use theEDIT keys toselecta channel from 1 to 28. Press when finished.
5 If is chosen, choose the REPEAT (TIMES) LOOP and
LOOPBACK
SINGLE CHANNEL
SINGLE CHANNEL
END EDIT
MESS, in the range 1 to 15.
6 If is chosen, choose the BURST LENGTH (TIMES).
ALARM/ STATUS
7 Choose TRANSMIT NEW CODE or to transmit the
selected FEAC message.

TIP: To View FEAC Messages

The received FEAC message can be viewed on the display.
BURST
ON
RESULTS
54
Selecting Test Features

Setting PDH Spare Bits

Setting PDH Spare Bits
Description Certain Spare Bits will cause the occurrence of a minor alarm when
received as a logical "0".: 140 Mb/s - FAS Bit 14
34 Mb/s - FAS Bit 12 8 Mb.s - FAS Bit 12 2 Mb/s - NFAS Timeslot (timeslot 0 of NFAS frame) Bit 0
HOW TO: 1 If SDH interface is chosen, set up the SDH transmit interface and
payload required. See "Setting SDH Transmit Interface " page 12. If PDH interface is chosen, set up the PDH transmit interface and payload required. See "Setting PDH Transmit Interface " page 10.
2 Set the value of the spare bits required for testing.
If a BIT SEQUENCE is required, choose SEND SEQUENCE to transmit the sequence.
ON
55
Selecting Test Features

Adding Pointer Adjustments

Adding Pointer Adjustments
Description The transmitted AU or TU pointer value can be adjusted for testing
purposes.
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12.
2 Choose the POINTER TYPE. 3 Choose the ADJUSTMENT TYPE required.
BURST - You determine the size of the burst by the number of PLACES chosen. If, for example, you choose 5 PLACES the pointer value will be stepped 5 times in unit steps e.g. 0 (start value), 1, 2, 3, 4, 5 (final value). The interval between steps is as follows: For AU and TU-3, the minimum spacing between adjustments is 500 us.ForTUexcept TU-3,theminimum spacingbetweenadjustments is 2 ms. Choose ADJUST POINTER [ON] to add the chosen burst.
NEW POINTER- Youcanchoose apointer value inthe range 0to 782 with or without a New Data Flag. The current pointer value is displayed for information purposes. Choose ADJUST POINTER [ON] to transmit the new pointer value.
56
Selecting Test Features
Adding Pointer Adjustments
OFFSET - You can frequency offset the line rate or the VC/TU rate, relative toeachother,thus producing pointer movements.If you offset the AU pointer, an 87:3 sequence of pointer movements is generated. The available configurations are listed in the following table. If you are currently adding Frequency Offset to the SDH interface or payload, pointer OFFSET is not available.
Pointer Type Line Rate AU Payload (VC) Rate TU Payload (TU) Rate
AU Constant Offset Tracks AU Payload AU Offset Constant Constant TU Constant Constant Offset TU Offset Tracks Line Rate Constant
G.783 - Provides pointer movements according to ITU-T G.783: Choose the G.783 ADJUSTMENT TYPE. Choose the POLARITY, INTERVAL and PATTERN (where applicable) for the selected sequence. Choose POINTER SEQUENCES to generate the selected G.783 sequence and to stop the pointer sequences.
STOP INIT
START INIT

G.783 Pointer Sequences Explained

In addition to the BURST, NEW POINTER and OFFSET pointer movements described, the HP 37718A can also generate pointer sequences (pointer movements) according to ITU-T G.783,T1.105.03 and GR-253. Note that T.105.03/GR-253 sequences are explained in the SONET version of this User’s Guide.
Before running a pointer sequence you can elect to run an initialization sequence, followed by a cool down period, and then run the chosen sequence. This is selected using the key shown in the display on the previous page. Initialized pointer sequences are made up of three periods: the Initialization Period, the Cool Down Period, and the Sequence (Measurement) Period, illustrated in the following figure:
START INIT
57
Selecting Test Features
Adding Pointer Adjustments
Non Periodic Sequence
Periodic Sequence
Initialization Sequence
Initialization
No Pointer Activity
Continuous Sequence
Cool Down
Sequence
Time
Measurement
Period
Note: SINGLE (e), BURST (f) and PHASE TRANSIENT are Non Periodic Sequences.
Initialization Period
For SINGLE e), BURST f) and PHASE TRANSIENT sequences the initialization sequence consists of 60 seconds of pointer adjustments applied at a rate of 2 adjustments per second and in the same direction as the specified pointer sequence.
Cool Down Period
A period following the initialization periodwhichforSINGLE e), BURST f) and PHASE TRANSIENT sequences is 30 seconds long when no pointer activity is present.
Sequence (Measurement) Period
The period following the Cool Down period where the specified pointer sequence runs continuously.
Periodic Test Sequences
For periodic test sequences (for example “PERIODIC ADD g/h”) both the 60 second initialization and 30 second cool down periods consist of the same sequence as used for the subsequent measurement sequence. If the product of the period T and the selected optional background pattern (87+3 or 26+1) exceeds 60 seconds then the longer period is used for the initialization. For example, if T is set for 10 seconds then the initialization period may be extended to 900 seconds.
The HP 37718A displays a message indicating which phase (initialization, cool down or measurement) the transmitter is currently generating.
58
Selecting Test Features
Adding Pointer Adjustments
NOTE The following conditions apply for pointer sequence generation:
The sequences can only be applied to the AU pointer when the AU does not contain a TU structure, otherwise it is applied to the TU pointer. Pointer sequence generation is not available when a frequency offset is being applied to the Line Rate.
The following figure gives an example of a G.783 (g) 87-3 Pointer Sequence.
G.783(g) 87-3 Pattern
No Pointer Adjustment
Pointer Adjustment
Start of Next 87-3 Pattern
Pointer Sequence
G.783(a) PERIODIC SINGLE
G.783 (b) PERIODIC ADD
G.783 (c) PERIODIC CANCEL
Periodic Single adjustments, each with opposite polarity to the preceding adjustment. The interval between pointer adjustments is user selectable (see Note 1 page 62).
Periodic Single adjustments, with selectable polarity and added adjustment (1 extra). The spacing between the added adjustment and the previous adjustment is set to the minimum, (see Note 2 page 62). The interval between pointer adjustments is user selectable (see Note 1). Added adjustments occur every 30 seconds.
Periodic Single adjustments, with selectable polarity and cancelled adjustment (1 less). The interval between pointer adjustments is user selectable (see Note 1 page 62). Cancelled adjustments occur every 30 seconds.
87
3
An Example of a Pointer Sequence
Description
59
Selecting Test Features
Adding Pointer Adjustments
Pointer Sequence
G.783(d) PERIODIC DOUBLE
G.783 (e) SINGLE
G.783 (f) BURST
PHASE TRANSIENT
G.783 (g) PERIODIC NORMAL (87-3 Pattern)
Description
Periodic Double adjustments (pair of adjustments). The pair alternate in polarity. The spacing between pairs of adjustments, of like polarity is set to the minimum (see Note 2). The interval between pointer adjustments is user selectable (see Note 1).
Periodic Single adjustments, all of the same polarity which is selectable. Separation between pointer adjustments is fixed at approximately 30 seconds.
Periodic bursts of 3 adjustments, all of the same polarity which is selectable. The interval between bursts is fixed at approximately 30 seconds. The interval between adjustments within a burst is set to the minimum (see Note 2 page 62).
Phase transient pointer adjustment burst test sequence. All adjustments are of the same polarity, which is selectable. The interval between bursts is fixed at 30 seconds. Each burst consists of 7 pointer movement. The first 3 in each burst are 0.25 s apart, and the interval between the 3 and 4 movement, and each remaining movement 0.5 seconds.
An 87-3 pattern is selected. The sequence pattern is 87 pointer movements followed by 3 missing pointer movements. Pointer polarity is selectable and the time interval between pointer adjustments settable (see Note 1 page 62).
G.783 (g) PERIODIC ADD (87-3 Pattern)
An 87-3 pattern is selected. The sequence pattern is 87 pointer movements followedby3missing pointer movements with anadded pointer movement after the 43rd pointer. The spacing between the added adjustment and the previous adjustment is set to the minimum, (see Note 2 page 62). Pointer polarity is selectable. The time interval between pointer adjustments can be set (see Note 1). Added adjustments occur every 30 seconds or every repeat of the 87­3 pattern, whichever is longer.
60
Selecting Test Features
Adding Pointer Adjustments
Pointer Sequence
G.783 (g) PERIODIC CANCEL (87-3 pattern)
G.783 (h) PERIODIC NORMAL (Continuous Pattern)
G.783 (h) PERIODIC ADD (Continuous Pattern)
G.783 (h) PERIODIC CANCEL (Continuous Pattern)
Description
An 87-3 pattern is selected. The sequence pattern is 87 pointer movements followed by 3 missing pointer movements with a cancelled pointer movement at the 87th pointer. Pointer polarity is selectable, and the time interval between pointer adjustments can be set (see Note1).Cancelledadjustments occur every 30 seconds or every repeat of the 87-3 pattern, whichever is longer.
Provides a continuous sequence of pointer adjustments. The polarity of the adjustments is selectable, and the time interval between adjustments can be set (see Note 1).
Periodic Single adjustments, with selectable polarity and added adjustment (1 extra). The spacing between the added adjustment and the previous adjustment is set to the minimum, (see Note 2). The time interval between pointer adjustments can be set (see Note
1). Added adjustments occur every 30 seconds or every repeat of the 87-3 pattern, whichever is longer.
Periodic Single adjustments, with selectable polarity and cancelled adjustment (1 less). The time interval between pointer adjustments can be set (see Note 1). Cancelled adjustments occur every 30 seconds or every repeat of the 87-3 pattern, whichever is longer.
PERIODIC NORMAL (26-1 Pattern)
This selection is only available if you have selected TU11 mapping, or TU12 with ASYNC DS1 selected. The sequence pattern is 26 pointer movements followed by 1 missing pointer movement. Pointer polarity is selectable and the time interval between pointer adjustments programmable to 200 ms, 500 ms, 1 s, 2 s, 5 s or 10 seconds.
61
Selecting Test Features
Adding Pointer Adjustments
Pointer Sequence
PERIODIC ADD (26-1 Pattern)
PERIODIC CANCEL (26-1 pattern)
This selection is only available if you have selected TU11 mapping, or TU12 with ASYNC DS1 selected. The sequence pattern is 26 pointer movements followed by 1 missing pointer movement. The added adjustment occurs 2 ms after the 13th pointer adjustment. Pointer polarity is selectable and the time interval between pointer adjustments programmable to 200 ms, 500 ms, 1 s, 2 s, 5 s or 10 s. Added adjustments occur every 30 seconds or every repeat of the 26­1 pattern, whichever is longer.
This selection is only available if you have selected TU11 mapping, or TU12 with ASYNC DS1 selected. The sequence pattern is 26 pointer movements followed by 1 missing pointer movement. The cancelled adjustment is the26thpointeradjustment,that is the one before the regular gap of 1. Pointer polarity is selectable and the time interval between pointer adjustments programmable to 200 ms, 500 ms, 1 s, 2 s, 5 s or 10s. Cancelled adjustments occur every 30 seconds or every repeat of the 26-1 pattern, whichever is longer.
Pointer Sequence Notes
Note 1: For AU and TU-3, the sequence interval is selectable from:
7.5 ms, 10, 20, 30, 34 ms 40 to 100 ms in 10 ms steps, 100 to 1000 ms in 100 ms steps 1, 2, 5, 10 seconds. For TU except TU-3, the sequence interval is selectable from: 200 ms, 500 ms, 1, 2, 5 and 10 seconds.
Description
Note 2:ForAUandTU-3, theminimumspacing betweenadjustments is 500 us. For TU except TU-3, the minimum spacing between adjustments is 2 ms.
62
Selecting Test Features

Using Pointer Graph Test Function

Using Pointer Graph Test Function
Pointer Graph shows the relative offset during the measurement period. This allows the time relationship of AU or TU pointer movements to be observed. Up to4days of storage allows long termeffectssuchas Wander to be observed. If an alarm occursduringthemeasurementperiod, a new graph starts at the centre of the display (offset zero) after recovery from the alarm.
The Pointer Graph display can be logged to the chosen logging device. See "Logging on Demand " page 100.
TIP: The graph can also be viewed on the display
at the end of the measurement.
HOW TO: 1 Setupthe receiveSDH interfaceand payloadas required.See“Setting
SDH Receive Interface” page 21.
2 Choose the CAPTURE INTERVAL required.
The capture interval determines the time between captures. Low values of capture interval should be chosen when a high degree of pointer movements is expected. High values ofcaptureinterval should be chosen when alowdegree of pointer movements is expected, for example Wander over 1 day, use 5 MINS and Wander over 4 days, use 20 MINS.
RESULTS
SDH RESULTS
63
Selecting Test Features
Using Pointer Graph Test Function
If, during a long term measurement (4 days), an event occurs at a particular time each day, a short term measurement can be made at the identified time to gain more detail of the event.
3 Choose the POINTER UNDER TEST type. 4 Press to start the measurement.
RUN/STOP
TIP: If the event occurs outside normal working hours, a Timed Start
measurement can be made. 1 SEC - display window of approximately 5 minutes. 5 SECS - display window of approximately 25 minutes. 20 SECS - display window of approximately 1 hour 40 minutes. 1 MIN - display window of approximately 5 hours. 5 MIN - display window of approximately 1 day. 20 MIN - display window of approximately 4 days.
64
Selecting Test Features

Stressing Optical Clock Recovery Circuits

Stressing Optical Clock Recovery Circuits
Description Ideally clock recovery circuits in the network equipment optical
interfaces should recover the clock even in the presence of long strings of 0’s. You can check the performance of your optical clock recovery circuits using the STRESS TEST test function.
The stress test is available at all optical rates.
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12. Choose the required STRESSING PATTERN.
The G.958 test pattern consists of 7 consecutive blocks of data as follows: the first row of section overhead bytes, ALL ONES, a PRBS, the first row of section overhead bytes,ALL ZEROS, a PRBS and the first row of section overhead bytes.
2 If you choose ALL ONES or ALL ZEROS as the stressing pattern,
choose the number of bytes in the BLOCK LENGTH.
65
Selecting Test Features

Generating Automatic Protection Switch Messages

Generating Automatic Protection Switch Messages
Description You can program the K1 and K2 bytes to exercise the APS functions for
Both LINEAR (ITU-T G.783) and RING (ITU-T G.841) topologies.
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12.
2 Choose the ITU-T TOPOLOGY required. 3 Choose the message to be transmitted.
If LINEAR topology is chosen, choose the CHANNEL, the BRIDGED CHANNEL NO., the ARCHITECTURE and the RESERVED bits you require. If RING topology is chosen, choosetheDESTINATIONNODE ID, the SOURCE NODE ID, the type of PATH and the status code (K2 Bits 6­>8) The currentTXand RX, K1 and K2,valuesare displayed for reference only.
4 Choose to transmit the new K1/K2 values.
66
DOWNLOAD
Selecting Test Features

Inserting & Dropping Data Communications Channel

Inserting & Dropping Data Communications Channel
Description The Data Communications Channel (DCC) of the regenerator and
multiplexer section overhead can be verified by protocol testing. The Insert and Drop capability provides access to the DCC via the RS-449 connector on the front panel of the SDH module.
DCC INSERT is available on the , , display.
DCC DROP is available on the display.
HOW TO: 1 Connect the Protocol Analyzer to the DCC port on the Multirate
Analyzer module.
2 Choose the required DCC.
TRANSMIT
RECEIVE
SDH TEST FUNCTION
SDH TEST FUNCTION
67
Selecting Test Features
Inserting & Dropping Data Communications Channel
68
3

3 Making Measurements

Making Measurements

Using Overhead BER Test Function

Using Overhead BER Test Function
Description You can perform a Bit Error Rate test on chosen bytes of the regenerator
section, multiplexer section and path overhead bytes. You can access the transmit Overhead BER on the
TEST FUNCTION
display.
TRANSMIT
SDH
HOW TO: 1 Setupthe SDHtransmitinterface andpayloadrequired. See "Setting
SDH Transmit Interface " page 12.
2 Set up the receive SDH interface and payload as required. See
"Setting SDH Receive Interface " page 21.
3 Choose the overhead byte to be tested on the
TEST FUNCTION
display.
RECEIVE
SDH
4 Choose the overhead byte to be tested on the
TEST FUNCTION
5 Press to start the test.
RUN/STOP
display.
6 The PRBS pattern can be errored by pressing .
TRANSMIT
SINGLE
70
SDH
Making Measurements

Test Timing

Test Timing
Description There are two aspects to test timing:
Error results may be displayed as short term or cumulative over the measurement period.If short term error measurements are required, the short term period may be selected.
The period of the test may be defined or controlled manually.
HOW TO: 1 Choose on the display.
TIMING CONTROL
RESULTS
2 Choose the SHORT TERM PERIOD to the timing required for short
term results.
3 Choose the type of TEST TIMING required:
For manual control with choose .
RUN/STOP
MANUAL
For a single timed measurement period started with , choose and choose the Test duration.
SINGLE
Fora timed period starting at a specified time, choose , choose the Test duration and the test START date and time.
RUN/STOP
TIMED
71
Making Measurements

Making SDH Analysis Measurements

Making SDH Analysis Measurements
Description G.826 analysis results are provided for all relevant SDH error sources.
In addition the following results are provided:
Cumulative error count and error ratio Short Term error count and error ratio Alarm Seconds Frequency Pointer Values Pointer Graph
HOW TO: 1 Set up the receive SDH interface and payload required. See "Setting
SDH Receive Interface " page 21.
2 If required set up the SDH transmit interface and payload. See
"Setting SDH Transmit Interface " page 12.
3 Press to start the measurement. 4 You can view the analysis results on the
display.
TIP: The measurement will not be affected if you switchbetweenthedifferent
results provided.
72
RUN/STOP
RESULTS
SDH ANALYSIS
Making Measurements

Making PDH Analysis Measurements

Making PDH Analysis Measurements
Description G.821, G.826, M.2100, M.2110 and M.2120 analysis results are provided
for all relevant PDH and PDH Payload error sources. In addition the following results are provided:
Cumulative error count and error ratio Short Term error count and error ratio Alarm Seconds SIG/BIT Monitor. See "Monitoring Signaling Bits " page 78.
HOW TO: 1 If SDH is chosen as the interface, set up the Receive Interface and
Payload required. See "Setting SDH Receive Interface " page 21. If required set up the Transmit Interface and Payload. See "Setting SDH Transmit Interface " page 12.
2 IfPDHis chosenas theinterface, setupthe PDHreceive interface.See
"Setting PDHReceive Interface " page 19. If requiredset up the PDH
transmit interface. See "Setting PDH Transmit Interface " page 10.
3 Press to start the measurement.
RUN/STOP
4 If SDH is chosenastheinterface, you can view the analysis results on
the display
RESULTS
PDH PAYLOAD
ERROR ANALYSIS
If PDH ischosenasthe interface, you can view the analysisresultson the display.
RESULTS
PDH ERROR ANALYSIS
73
Making Measurements

Measuring Frequency

Measuring Frequency
Description The signal frequency and the amount of offset from ITU-T standard rate
can be measured to give an indication of probability of errors.
HOW TO: 1 Connect the signal to be measured to the IN port of the PDH/DSN
RECEIVE module or the IN port of the Multirate Analyzer module (SDH electrical) or the IN port of the Optical Interface module (SDH optical).
NOTE Frequency measurement is always available even if test timing is off.
74
Making Measurements

Measuring Optical Power

Measuring Optical Power
Description Optical power measurement can be performed on the SDH signal
connected to the STM-1/STM-4 In port.
HOW TO: 1 Connect the SDH optical signal to the IN port of the Optical Interface
module.
2 Choose the received input signal rate on the display.
NOTE Optical power measurement is always available even if test timing is off.
RECEIVE
SDH
75
Making Measurements

Measuring Round Trip Delay

Measuring Round Trip Delay
Description: The time taken for voice traffic to pass through the network is very
important. Excessive delay can make speech difficult to understand. The Round Trip Delay feature of the HP 37718A measures the delay in a 64 kb/s timeslot. A test pattern is transmitted in the 64 kb/s timeslot and a timer is set running. A loopback is applied to the network equipment to return the test signal. The received pattern stops the timer and the Round Trip Delay is calculated.
NOTE You can only measure Round Trip Delay on a 64 kb/s test signal obtained
from a 140 Mb/s, 34 Mb/s, 8 Mb/s or 2 Mb/s PDH/DSn interface or PDH/ DSn payload signal.
HOW TO: 1 If measuring on an SDH interface, set up the SDH transmit and
receive interfacesandpayloads required. See "Setting SDH Transmit Interface " page 12 and “Setting SDH Receive Interface” page 21.
2 If measuringon a PDHinterface,set upthePDH transmit andreceive
interfaces and payloads required. See “Setting PDH Transmit Interface” page 10 and “Setting PDH Receive Interface” page 19.
3 Connect a loopback to the network equipment.
76
Making Measurements
Measuring Round Trip Delay
4 Choose ACTION to start the measurement.
ON
If measuring on an SDH interface, the results are available on the
RESULTS
PDH PAYLOAD
display.
If measuring on a PDH interface, the results are available on the
display.
RESULTS
PDH
The Round Trip delay measurement range is up to 2 seconds. The resolution varies with the received interface signal rate:
2 Mb/s 1 microsecond 8, 34, 140 Mb/s 10 microseconds STM-0,STM-1 0.5 milliseconds
STM-4, STM-16 0.5 milliseconds
77
Making Measurements

Monitoring Signaling Bits

Monitoring Signaling Bits
Description The HP 37718A receiver can be used to monitor the state of signaling
bits in received 2 Mb/s signals with timeslot-16 CAS multiframing (PCM30 or PCM30CRC) and DS1 structured signals.
2.048 Mb/s Results

DS1 Results D4 and SLC-96 payloads

For 2 Mb/s signals with timeslot-16 CAS multiframing a table showing the values of A,B,C,D signaling bits in all 30 channels is given.
A table simultaneously showing the state of the A and B signaling bits in the 6th and 12th frames of a superframe is given. Each frame contains 24 timeslots. In SLC-96 mode A and B choices are 0, 1 or alternating. If you set bit A or B to alternate, the displayed bit changes to an A, to indicate that the bit is alternating from 1 to 0. The same signaling is transmitted in all channels.

ESF Payloads

A table simultaneously showing the state of the A, B, C and D signaling bits in the 6th, 12th, 18th and 24th frames of a superframe is given. Each frame contains 24 timeslots.
78
Making Measurements

Measuring Service Disruption Time

Measuring Service Disruption Time
Description: Protection switching ensures that data integrity is maintained and
revenue protectedwhenequipment failure occurs. The speedofoperation of the protection switch can be measured.
The sequence of events involved in measuring the switching time is:
Pattern Synchronization (no errors) is achieved.
The protection switch is invoked - Pattern Synchronization is lost.
The standby line is in place - Pattern Synchronization is regained.
The time interval between pattern sync loss and pattern sync gain is a measure of the disruption of service due to protection switching.
Service Disruption is chosen on the page except for the following configuration:
If you choose a PDH or SDH/SONET interface and an ANSI (DS1, DS3) framed, unstructured payload you must select Service Disruption ontheTransmitter and Receiver display.
RESULTS
TEST FUNCTION
79
Making Measurements
Measuring Service Disruption Time
NOTE At DS1 and DS3, Service Disruption results are only available for
Unstructured payloads.
Error Burst Definition
Error bursts start and finish with an error. Bursts of less than 10 us are ignored. Bursts are assumed to have completed when >2000ms elapses without any errors being received. The longest burst detected is 2 seconds.
Accuracy
300 us for DS1, 2Mb/s and 34Mb/s signals. 60 us for DS3 signals.
HOW TO: 1 If interfacing at SDH set up the SDH transmit and receive interfaces
and payloads required. See "Setting SDH Transmit Interface " page 12 and "Setting SDH Receive Interface " page 21.
2 If interfacing at PDH/DSn set up the PDH/DSn transmit and receive
interfaces and payloads as required. See "Setting PDH Transmit Interface " page 10 and "Setting PDH Receive Interface " page 19.
3 If you choose a DS1 or DS3 framed unstructured payload, choose
SERVICE DISRUPT
on the and
TRANSMIT
RECEIVE
TEST FUNCTION
displays.
80
Making Measurements
Measuring Service Disruption Time
4 Press to start the measurement.
RUN/STOP
5 Invoke the protection switch. 6 View the results on the display.
RESULTS
SRVC DISRUPT
Results Displayed LONGEST - Longest burst of errors during measurement.
SHORTEST - Shortest burst of errors during measurement. LAST - Length of last burst of errors detected during measurement.
81
Making Measurements

Performing an SDH Tributary Scan

Performing an SDH Tributary Scan
Description Tributary Scan tests each tributary for error free operation and no
occurrence of Pattern Loss. A failure is indicated by highlighting the tributary in which the failure occurred. The
MAIN SETTINGS
, mapping setup determines the tributary structure.
TRANSMIT
The HP 37718A will configure the Transmitter to the Receiver and the PATTERN is forced to the payload it will fill.
The SDH Tributary Scan display can be logged to the chosen logging device. See "Logging on Demand " page 100.
SDH
HOW TO: 1 Set up the transmit and receive SDH interfaces and payload as
required. See "Setting SDH Transmit Interface " page 12 and
"Setting SDH Receive Interface " page 21.
2 Choose the required BIT ERROR THRESHOLD.
This determines the error rate above which a failure is declared.
3 Choose the required TEST TIMING.
The valueyouchoose is the testtimefor each individual tributary and not the total test time. For example, 63 TU-12 tributaries in an AU-4 - the time taken to complete the Tributary Scan will be 63 X TEST TIMING choice.
82
Making Measurements
Performing an SDH Tributary Scan
4 The Tributary Scan results can be viewed on the
SDH TRIBSCAN
The Scan can be started on the display or the display by choosing START. If the Scan is started on the display, the HP 37718A changes to the display.
display.
TRANSMIT
RESULTS
TRANSMIT
RESULTS
If a single path, for example, SIGNAL [STM-1] MAPPING AU-4 [VC­4] is chosen, then Tributary Scan is disabled.
NOTE The keyboard is locked during tributary scan.
RESULTS
SDH TEST FUNCTION
SDH TEST FUNCTION
83
Making Measurements

Performing an SDH Alarm Scan

Performing an SDH Alarm Scan
Description SDH Alarm Scan tests each channel for alarm free operation and
identifies and indicates any Unequipped channels. You can configure the Scan to check for the occurrence of any Path layer BIP errors above a chosen threshold. The channel in which an alarm occurred is highlighted if any of the following alarms occur: AU-LOP, HP-RDI, AU-AIS, H4 Loss of Multiframe, TU-AIS, LP-RDI, TU-LOP
The SDH Alarm Scan display can be logged to the chosen logging device. See "Logging on Demand " page 100.
HOW TO: 1 Setupthe receiveSDH interfaceand payloadas required.See“Setting
SDH Receive Interface” page 21.
2 Choose on the display.
SDH ALM SCAN
RESULTS
3 Choose AUTO or RX SETTINGS.
RX SETTINGS: The scan checks the structure set on the
SDH
display.
RECEIVE
AUTO: The scan checks the structure being received. This can be particularly useful when receiving mixed payloads.
4 Choose the BIP error threshold. 5 Choose to start the Alarm Scan.
START
84
Making Measurements

Performing a PDH/DSn Alarm Scan

Performing a PDH/DSn Alarm Scan
Description PDH Alarm Scan tests each channel for the following alarms:
Frame Loss RAI AIS
The channel in which an alarm occurs is highlighted.
HOW TO: 1 Set up the receive PDH interface as required. See “Setting PDH
Receive Interface” page 19.
2 Choose to start the Alarm Scan.
ON
85
Making Measurements
Performing a PDH/DSn Alarm Scan
86
4

4 Storing, Logging and Printing

Storing, Logging and Printing

Saving Graphics Results to Instrument Store

Saving Graphics Results to Instrument Store
Description Graphical representation of measurement results is very useful
particularly during a long measurement period. It provides an overview of the results and can be printed for record keeping.
Graphics results can be stored in instrument graph storage or on floppy disk.
HOW TO: 1 Before starting your measurement, choose the GRAPH STORAGE
resolution and location. The resolution chosen affects the ZOOM capability when viewing the bar graphs. If 1 MIN is selected, 1 MIN/BAR, 15 MINS/BAR and 60 MINS/BAR are available. If 15 MINS is selected, 15 MINS/BAR and 60 MINS/BAR are available. If 1 HOUR is selected, 60 MINS/BAR is available. The graphics results can be stored in the instrument - INTERNAL or stored on DISK. Storage to disk will use a default file name unless a file name is specified on the display. See “Saving Graphics Results to Disk” page 126.
2 Press to start the measurement. Graphical results will be
88
RUN/STOP
stored in the chosen location.
OTHER
FLOPPY DISK
Storing, Logging and Printing

Recalling Stored Graph Results

Recalling Stored Graph Results
Description Results stored from a previous measurement can be recalled to the
graphics displays for viewing and printing.
HOW TO: 1 If currently viewingthebar graph display, select then
STORE STATUS
select .
STORE STATUS
. If currently viewing the error or alarm summary,
TEXT RESULTS
2 Using and , move the highlighted cursor to the store location
which contains the required results. If therequiredresults are stored onDisk,move the highlighted cursor to DISK and choose RECALL GRAPHICS on the FLOPPY DISK display. See “Recalling Graphics Results from Disk” page 131.
3 Choose if you wish to view the bar graphs.
GRAPH RESULTS
The display will change to the bar graph display of the highlighted results.
4 Choose if you wish to view the error and alarm
TEXT RESULTS
Summaries. The display will change to the text results display of the highlighted results.
DELETE STORE
If is chosen, a ;
DELETE ALL
deletes the results in the highlighted store.
CONFIRM DELETE ABORT DELETE
choice prevents accidental deletion of all the stored results.
89
Storing, Logging and Printing
Recalling Stored Graph Results
The top row of the display comprises five fields: Store Memory location in whichthedisplayedbar graph data
is stored. Move the highlighted cursor, to the STORE location desired, using and .
Start Date The start date of the test, which produced the stored
results.
Start Time The start time of the test, which produced the stored
results.
Test Duration The duration of the test, which produced the stored
results.
Store Use The percentage (%) of the overall storage capacity
occupied by each set of stored results. The TOTAL percentage used and the percentage still FREE is provided at the bottom of the STORE USE column.
90
Storing, Logging and Printing

Viewing the Bar Graph Display

Viewing the Bar Graph Display
Description All the graphic results obtained during the measurement are available
for viewing. Identify a period of interest and zoom in for more detailed examination.
HOW TO: 1 To view the current bar graphs, press and use
CHANGE UPPER
and to obtain the bar graphs
CHANGE LOWER
GRAPH
required.
2 To view previously stored graphs, see "Recalling Stored Graph
Results " page 89.
3 For more detailed inspection of the bar graph, position the cursor
centrally within the area of interest using , and select
ZOOM IN
to reduce the time axis to 15 MINS/BAR. This is only possible if the graphics results were stored with a STORAGE resolution of 1 SEC,1 MINS or 15 MINS. For further reduction of the time axis to 01 MINS/BAR or 01 SECS/ BAR, position the cursor centrally within the area of interest and select until the required time axis is obtained.
ZOOM IN
The top row of the display comprises three fields:
Store Memory location in whichthedisplayedbar graph data
is stored. Store can only be changed when the status of stored results is displayed. See "Recalling Stored Graph Results " page 89.
91
Storing, Logging and Printing
Viewing the Bar Graph Display
Zoom The width, in minutes, of each "bar" in the bar graph,
controlled by / .
ZOOM IN ZOOM OUT
Cursor The cursor position in terms of time and date,
controlled by and . The cursor position changes in steps of 1 second, 1 minute, 15 minutes or 60 minutes dependentupontheZOOM setting. The cursor is physically located between the two graphs.
92
Storing, Logging and Printing

Viewing the Graphics Error and Alarm Summaries

Viewing the Graphics Error and Alarm Summaries
Description The error and alarm summaries of the measurement chosen are
displayed on the display. The error summary or alarm summary can be viewed at any time.
TEXT RESULTS
HOW TO: 1 To view the error or alarm summary associated with the current bar
graphs, press then .
2 Toview the errororalarm summary associatedwithpreviously stored
bar graphs, see "Recalling Stored Graph Results " page 89.
3 To view the Alarms which have occurred during the measurement,
select .Use to viewthe PDH/DSn; and SDH Alarm Summaries in turn if applicable.
4 To view the Errors which have occurred during the measurement
select .Use to viewthe PDH/DSn; and SDH Error Summaries in turn if applicable. The top row of the display comprises three fields:
Store Memory location in which the bar graphs, error
ALARM SUMMARY NEXT SUMMARY
ERROR SUMMARY NEXT SUMMARY
GRAPH
summary and alarm summary are stored. Store can only be changed when the status of stored results is displayed. See "Recalling Stored Graph Results " page 89.
TEXT RESULTS
93
Storing, Logging and Printing
Viewing the Graphics Error and Alarm Summaries
Start The start time and date of the test, that produced the
displayed results.
Stop The stop time and date of the test, that produced the
displayed results.
94
Storing, Logging and Printing

Logging Graph Displays

Logging Graph Displays
Description The bar graphs and error and alarm summariescanbeloggedtothe disk
for printing at a later date. If Option 601, Remote Control, is fitted, the bar graphs and error and alarm summary can be logged to an external HP DeskJet printer at the end of the test period. If a printer is not immediately available, the graphics results remain in memory and can be logged at a later time when a printer becomes available.

HOW TO: Log to an External Printer

1 Connect an external RS-232-C HP DeskJet printer to the HP 37718A
RS232 port. See "Logging Results to RS-232-C Printer " page 105 or connect an external HP-IB HP DeskJet printer to the HP 37718A HP­IB port. See "Logging Results to HP-IB Printer " page 103 or connect a Parallel DeskJet printer to the HP 37718A Parallel port. See
"Logging Results to Parallel (Centronics) Printer " page 102.
2 Make the required selections on the display:
LOGGING PORT [HPIB] or [RS232] or [PARALLEL] and LOGGING [ON].
3 TologtheErrorandAlarmsummaries, the displayed Bar graphs and
the Alarm graph to the printer, choose on the bar graph display.
OTHER
PRINT
LOGGING
95
Storing, Logging and Printing
Logging Graph Displays
4 Choose to confirm or abort the print.
Toconfirmthe print and only print the portion of the graph displayed and the summaries choose . To confirm the print and print the graph for the whole measurement period and the summaries choose . To abort the print choose .
5 To log the selected Error and Alarm summaries to the printer, choose
PRINT
on the Text Results display.

HOW TO: Log to the Disk Drive

1 Insert a floppy disk in the disk drive.
THIS SCREEN
CURSOR TO END
ABORT
2 Choose LOGGING PORT on the display.
Enter a filename on the display. See "Saving
DISK
OTHER
OTHER
FLOPPY DISK
LOGGING
Data Logging to Disk " page 128.
3 TologtheErrorandAlarmsummaries, the displayed Bar graphs and
the Alarm graph to the disk, choose on the bar graph display.
PRINT
4 Choose to confirm or abort the print.
Toconfirmthe print and only print the portion of the graph displayed and the summaries choose .
THIS SCREEN
To confirm the print and print the graph for the whole measurement period and the summaries choose . To abort the print choose .
ABORT
CURSOR TO END
5 To log the selected Error and Alarm summaries to the disk, choose
PRINT
on the Text Results display.
96
Storing, Logging and Printing

Logging Results

Logging Results

Description Test Period Logging

If degradations in system performance can be observed at an early stage, then the appropriate remedial action can be taken to maximize circuit availability and avoid system crashes. Test period logging allows you to monitor the error performance of your circuit. At the end of the test period the selected results are logged. Results can be logged at regular intervals during the test period by selecting a LOGGING PERIOD of shorter duration than the test period. An instant summary of the results can be demanded by pressing without affecting the test in progress.

Error Event Logging

Manual tracing of intermittent faults is time consuming. Error event logging allows you to carry out unattended long term monitoring of the circuit. Each occurrence of the selected error event is logged.
PRINT NOW
The results obtained during the test are retained in memory until they are overwritten by the next set of results. The results can be logged at any time during the test period and at the end of the test period. The results required are selected using LOGGING SETUP .
Any Alarm occurrence results in a timed and dated message being logged.
BER and Analysis results can be selected by the user. Cumulative and Period versions of the results are calculated and can be
selected by the user.
Period The results obtained over a set period of time during
Cumulative The results obtained over the time elapsed since the
CONTROL
the test. The Period is defined by the LOGGING PERIOD selection.
start of the test.
OTHER
LOGGING
97
Storing, Logging and Printing
Logging Results
The results can be logged to the following devices, selectable using
OTHER
LOGGING DEVICE
LOGGING SETUP :
Optional Internal printer fitted into the instrument front cover (Option 602)
External HP-IB printer (option 601)
External RS-232-C printer (option 601)
External Parallel Port printer (option 601)
Disk Drive
HOW TO: 1 Choose LOGGING [ON] - enables the logging of results and alarms.
2 Choose LOGGING PERIOD - determines how regularly the results
and alarms are logged. USER PROGRAM provides a choice of 10 minutes to 99 hours.
3 Choose RESULT LOGGED - allows you to log all results to or choose
only those results you require.
4 Choose WHEN - allows you to choose to only log when the error count
for the logging period isgreaterthan0. If the error count is 0 then the message NO BIT ERRORS is displayed.
5 Choose CONTENT - allows you a choice of error results to be logged.
Error Results, Analysis or Error and Analysis (ER & ANAL) and Period, Cumulative or Period and Cumulative (PER & CUMUL).
98
Storing, Logging and Printing
Logging Results
6 If LOG ERRORSECONDS[ON] is chosen a timedanddated message
is logged each time an error second occurs (excessive occurrences of error seconds during the logging period will result in heavy use of printer paper).
7 Choose the logging DEVICE.
If RS232 is chosen, see "Logging Results to RS-232-C Printer " page 105. If HPIB is chosen, see "Logging Results to HP-IB Printer " page 103. If PARALLEL ischosen,see "Logging Results to Parallel(Centronics) Printer " page 102. If DISK is chosen, see “Saving Data Logging to Disk” page 128. If Option602,Internal Printer, is fittedandINTERNAL is chosen, see
"Logging Results to Internal Printer " page 104.
99
Storing, Logging and Printing

Logging on Demand

Logging on Demand
Description When ispressedthe chosenresults are logged to the chosen
logging device. The choice of results for logging is:
PRINT NOW
RESULTS SNAPSHOT - last recorded measurement results OVERHEAD SNAPSHOT - last recorded overhead values of the chosen STM-1 OVERHEAD CAPTURE - Overhead Capture display SCREEN DUMP - allows logging of the chosen display POINTER GRAPH - Pointer Graph display SDH TRIBUTARY SCAN - SDH Tributary Scan display SDH ALARM SCAN - SDH Alarm Scan display SELTEST FAILS - Last recorded selftest failures
HOW TO:
1 Choose LOG ON DEMAND to determine results to be logged when
PRINT NOW
SCREEN DUMP allows you to log the selected display when
PRINT NOW
using this feature).
2 Choose the logging DEVICE.
If RS232 is chosen, see "Logging Results to RS-232-C Printer " page 105. If HPIB is chosen, see "Logging Results to HP-IB Printer " page 103.
100
is pressed. is pressed. (Logging or Disk displays cannot be logged
Loading...