Agilent Technologies J-BERT N4903B User manual

S
Agilent J-BERT N4903B
High-Performance Serial
BERT
User Guide
sAgilent Technologies

© Agilent Technologies, Inc. 2014
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Manual Part Number
N4903-91021
Edition
Release Edition, June 2014
Printed in Germany
Agilent Technologies, Deutschland GmbH
Herrenberger Str. 130
71034 Böblingen, Germany
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Safety Notices
CAUTION
A CAUTION notice denotes a hazard. It
calls attention to an operating
procedure, practice, or the like that, if not
correctly performed or adhered to, could
result in damage to the product or loss
of important data. Do not proceed
beyond a CAUTION notice until the
indicated conditions are fully
understood and met.
WARNING
A WARNING notice denotes a hazard.
It calls attention to an operating
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could result in personal injury or death.
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Notices

Contents
1Planning the Test
Planning the Test - Concepts 11
Introduction to the Serial BERT 11
Introduction to the Serial BERT - Concepts 11
Navigating the Serial BERT GUI 18
Navigating the Serial BERT GUI - Concepts 18
Which Test is Appropriate? 25
Which Test is Appropriate? - Concepts 25
Connecting the DUT 29
Connecting the DUT - Concepts 29
2Setting up External Instrument(s)
Setting up External Instrument(s) - Concepts 37
Setting up External Instrument(s) - Procedure 42
Setting up External Instrument(s) - Reference 51
3Setting up Patterns
Setting up Patterns - Concepts 61
User Patterns 65
User Patterns - Concepts 65
User Patterns - Procedures 71
User Patterns - Reference 76
Software-Generated PRBS 91
Software-Generated PRBS - Concepts 91
Software-Generated PRBS - Procedures 93
Software-Generated PRBS - Reference 93
Hardware-Generated PRBS 93
Hardware-Generated PRBS - Concepts 93
Hardware-Generated PRBS - Procedures 95
Hardware-Generated PRBS - Reference 95
Agilent J-BERT N4903B High-Performance Serial BERT 3

User-Defined Sequences 96
User-Defined Sequences - Concepts 96
User-Defined Sequences - Procedures 99
User-Defined Sequences - Reference 101
Sequencer-Pattern Editor 108
Sequencer-Pattern Editor - Concepts 108
Sequencer-Pattern Editor - Procedure 108
Sequencer-Pattern Editor - Reference 110
4Setting up the Pattern Generator
Setting up the Pattern Generator - Concepts 121
Input and Output Ports 122
Input and Output Ports - Concepts 122
Input and Output Ports - Procedures 131
Input and Output Ports - Reference 135
Bit Rate 139
Bit Rate - Concepts 139
Bit Rate - Procedures 141
Bit Rate - Reference 143
Trigger/Ref Clock Output 145
Trigger/Ref Clock Output - Concepts 145
Trigger/Ref Clock Output - Procedures 145
Trigger/Ref Clock Output - Reference 146
Aux Data Out 149
Aux Data Output - Concepts 149
Aux Data Out - Procedures 149
Aux Data Output - Reference 154
Delay Control Input 155
Delay Control Input - Concepts 155
Delay Control Input - Procedures 156
Delay Control Input - Reference 156
Error Addition/Insertion 157
Error Addition/Insertion - Concepts 157
Error Addition/Insertion - Procedures 157
Error Addition/Insertion - Reference 159
Pattern Alternation 161
Pattern Alternation - Concepts 161
Pattern Alternation - Procedures 162
Pattern Alternation - Reference 164
4Agilent J-BERT N4903B High-Performance Serial BERT

5Setting up the Error Detector
Setting up the Error Detector - Concepts 167
Inputs and Outputs 168
Inputs and Outputs - Concepts 168
Inputs and Outputs - Procedures 171
Data Input Setup - Reference 172
Clock Setup 173
Clock Setup - Concepts 173
Clock Setup - Procedures 178
Clock Setup - Reference 179
Error Ratio 182
Error Ratio - Concepts 182
Error Ratio - Procedures 185
Error Ratio - Reference 190
Sampling Point Setup 193
Sampling Point Setup - Concepts 193
Sampling Point Setup - Procedures 196
Sampling Point Setup - Reference 198
Trigger and Aux Output 203
Trigger and Aux Output - Concepts 203
Trigger and Aux Output - Procedures 203
Trigger and Aux Output - Reference 204
Pattern Synchronization 205
Pattern Synchronization - Concepts 205
Pattern Synchronization - Procedures 216
Pattern Synchronization - Reference 218
Error Accumulation 220
Error Accumulation - Concepts 220
Error Accumulation - Procedures 220
Error Accumulation - Reference 221
BER Location 223
BER Location - Concepts 223
BER Location - Procedures 223
BER Location - Reference 223
Audio Signals 224
Audio Signals - Concepts 224
Audio Signals - Procedures 225
Audio Signals - Reference 225
Agilent J-BERT N4903B High-Performance Serial BERT 5

6Advanced Analysis
Advanced Analysis - Concepts 227
Advanced Analysis - Procedures 229
Advanced Analysis - Reference 234
DUT Output Timing/Jitter 241
DUT Output Timing/Jitter - Concepts 241
DUT Output Timing/Jitter - Procedures 250
DUT Output Timing/Jitter - Reference 252
Output Levels 263
Output Levels - Concepts 263
Output Levels - Procedures 265
Output Levels - Reference 270
Eye Opening 287
Eye Opening - Concepts 287
Eye Opening - Procedures 289
Eye Opening - Reference 294
Error Location Capture 302
Error Location Capture - Concepts 302
Error Location Capture - Procedures 304
Error Location Capture - Reference 305
Fast Eye Mask 307
Fast Eye Mask - Concepts 307
Fast Eye Mask - Procedures 309
Fast Eye Mask - Reference 311
Eye Diagram 315
Eye Diagram - Concepts 315
Eye Diagram - Procedures 320
Eye Diagram - Reference 332
Spectral Jitter 342
Spectral Jitter - Concepts 342
Spectral Jitter - Procedures 351
Spectral Jitter - Reference 353
7Evaluating Results
Evaluating Results - Concepts 361
Instantaneous Measurements 361
Instantaneous Measurements - Concepts 361
Instantaneous Measurements - Procedures 363
Instantaneous Measurements - Reference 366
6Agilent J-BERT N4903B High-Performance Serial BERT

Accumulated Measurements 376
Accumulated Measurements - Concepts 376
Accumulated Measurements - Procedures 377
Accumulated Measurements - Reference 378
Eye Measurements 392
Eye Measurements - Concepts 392
Eye Measurements - Procedures 392
Eye Measurements - Reference 393
8Jitter Tolerance Tests
Jitter Tolerance Tests - Concepts 395
Jitter Setup 404
Jitter Setup - Concepts 404
Jitter Setup - Procedures 407
Jitter Setup - Reference 413
Interference Channel Setup 431
Interference Channel Setup - Concepts 431
Interference Channel Setup - Procedures 431
Interference Channel Setup - Reference 432
Jitter Tolerance Characterization 433
Jitter Tolerance Characterization - Concepts 433
Jitter Tolerance Characterization - Procedures 438
Jitter Tolerance Characterization - Reference 443
Jitter Tolerance Compliance 446
Jitter Tolerance Compliance - Concepts 446
Jitter Tolerance Compliance - Procedures 454
Jitter Tolerance Compliance - Reference 462
9Solving Problems
Solving Problems - Concepts 469
Setup Problems 469
Setup Problems - Concepts 469
Measurement Problems 472
Measurement Problems - Concepts 472
Other Messages 478
Other Messages - Concepts 478
N4916B System Setup Calibration 480
N4916B System Setup Calibration 480
Agilent J-BERT N4903B High-Performance Serial BERT 7

N4876A System Setup Adjustment 490
N4876A System Setup Adjustment 490
M8061A System Setup Adjustment 492
M8061A System Setup Adjustment 492
Problems with the N4916A 493
Problems with the N4916A - Concepts 493
Problems with the N4916B 500
Problems with the N4916B - Concepts 500
Problems with the N4876A 511
Problems with the N4876A - Concepts 511
Problems with the M8061A 518
Problems with the M8061A - Concepts 518
10 Customizing the Instrument
Customizing the Instrument - Concepts 525
Restoring the System 525
Agilent Recovery System - Procedures 525
Configuring the Instrument 528
Configuring the Instrument - Concepts 528
Configuring the Instrument - Procedures 529
Configuring the Instrument - Reference 531
Configuring the Touchscreen 531
Configuring the Touchscreen - Procedures 531
Configuring the Touchscreen - Reference 533
Installing Software Licenses 535
Installing Software Licenses - Procedures 535
Installing Software Licenses - Reference 535
Installing Hardware Options 536
Installing Hardware Options - Procedures 536
Installing External Instrument(s) 538
Installing External Instrument(s) - Concepts 538
Installing the N4916A/B - Procedure 539
Installing the N4876A - Procedure 544
Installing the M8061A - Procedure 549
Installing Webserver 551
Customizing the Web Server- Concept 551
Printing 555
Printing - Procedures 555
8Agilent J-BERT N4903B High-Performance Serial BERT

File Management 558
File Management - Procedures 558
Preset Instrument State 562
Preset Instrument State - Procedures 562
Self Test 563
Self Test - Concepts 563
Self Test - Procedures 563
Self Test - Reference 564
Index 567
Agilent J-BERT N4903B High-Performance Serial BERT 9

10 Agilent J-BERT N4903B High-Performance Serial BERT

1
Planning the Test
Planning the Test - Concepts
The following topics provide some information that can help you in planning tests
with the Serial BERT:
•“Introduction to the Serial BERT - Concepts ” on page 11 explains the basics
of bit error rates (BER) and BER testing with the Serial BERT.
•“Which Test is Appropriate? - Concepts ” on page 25 provides you with some
basic information about the types of testing you can do with the Serial BERT.
•“Connecting the DUT - Concepts ” on page 29 tells you how you should
connect your DUT to the Serial BERT.
Introduction to the Serial BERT
Introduction to the Serial BERT - Concepts
These topics explain some of the basics of BER, Serial BERT, and BER testing with
the Serial BERT.
Important Information about the Pattern Generator Outputs
The pattern generator output ports must be terminated with 50 Ω if they are not
connected:
• Data Out
• Data Out
• Clock Out
Agilent J-BERT N4903B High-Performance Serial BERT
User Guide
sAgilent Technologies 11
S

• Clock Out
• Aux Data Out
• Aux Data Out
• Trigger/Ref Clock Out
• Trigger/Ref Clock Out
Termination of output ports improves the test performance.
Important Information Regarding Security
The Serial BERT is a PC-based instrument with a standard Windows operating
system. As such, it is subject to the same security protection measures as any
other PC.
See the Microsoft web site for more information regarding data security:
http://www.microsoft.com/security/default.mspx
Every user must have administrator privileges to run the Serial BERT firmware.
Otherwise the firmware does not have access to the instrument's hardware.
In case of any serious malfunction in the operating system, the Agilent Recovery
System can be used to repair the system. See “Agilent Recovery System -
Procedures” on page 525.
Understanding BER
Bit error ratio (BER) is the most fundamental measure of system performance. It
is the ratio of the number of errored bits to the total number of bits received.
For example, 1 error in 1000 bits corresponds to a BER of 1/1000 or 1x10-3. This
would be displayed on the instrument as 1E-3. Refer to the following table to
familiarize yourself with how BERs are displayed. Notice that smaller exponents
correspond to higher BERs, and larger exponents correspond to lower BERs.
Table 1
Fraction Exponent Instrument Display
1/1 1 x 1001E+0
1/10 1 x 10-1 1E-1
1/100 1 x 10-2 1E-2
1/1000 1 x 10-3 1E-3
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12 Agilent J-BERT N4903B High-Performance Serial BERT

Table 1
Fraction Exponent Instrument Display
1/10,000 1 x 10-4 1E-4
1/100,000 1 x 10-5 1E-5
1/1,000,000 1 x 10-6 1E-6
1/10,000,000 1 x 10-7 1E-7
Understanding SER
Symbol error ratio (SER) is the symbol ratio of the number of errored symbols to
the total number of symbols received.
For example, a single error will result in a one symbol error in 1000 symbols where
each symbol consists of 10 bits that corresponds to a SER of 1/1000 or 1x10-3. This
would be displayed on the instrument as 1E-3. Refer to the following table to
familiarize yourself with how SERs are displayed. Notice that smaller exponents
correspond to higher SERs, and larger exponents correspond to lower SERs.
Table 2
Fraction Exponent Instrument Display
1/1 1 x 1001E+0
1/10 1 x 10-1 1E-1
1/100 1 x 10-2 1E-2
1/1000 1 x 10-3 1E-3
1/10,000 1 x 10-4 1E-4
1/100,000 1 x 10-5 1E-5
1/1,000,000 1 x 10-6 1E-6
1/10,000,000 1 x 10-7 1E-7
Planning the Test 1
Agilent J-BERT N4903B High-Performance Serial BERT 13

Understanding the Serial BERT
The Serial BERT, also referred to as a Bit Error Ratio Tester (BERT), is a powerful
instrument that enables you to analyze systems and components in the
telecommunication and enterprise communication industries. It is an essential tool
for designing and troubleshooting communications systems, high-speed integrated
circuits (ICs), and photonic components. Its intuitive operation and leading edge
performance will help you quickly verify error performance.
The Serial BERT comes with advanced jitter generation capabilities for jitter
tolerance testing (J-BERT). The instrument provides:
• Excellent waveform performance
• Outstanding rise times and jitter performance
• A choice of logic family interfaces
• Easy object-oriented programming with the IVI-COM interface
• Remote commands similar to HP/Agilent 71603B
• A variety of ways in which to accumulate and view test results
• A collection of example patterns
• Convenient online documentation
• Automatic setup of optimum sampling point
• A variety of powerful advanced analysis tools
• Special support for jitter analysis and characterization
Which Features are Available?
The Serial BERT is available with different options. They differ in the range of
provided bit rates and in the available features.
Depending on the options you bought or upgrated, you can have the following
installed:
• C07
Bit rate range: 150 Mbit/s to 7 Gbit/s pattern generator and error detector with
built-in clock data recovery (CDR)
• C13
Bit rate range: 150 Mbit/s to 12.5 Gbit/s pattern generator and error detector
with built-in CDR
• A01, U01
Bit Recovery Mode (measures BER without expecting a particular pattern)
• J10
1Planning the Test
14 Agilent J-BERT N4903B High-Performance Serial BERT

Option/Upgrade for jitter injection. Total jitter can be composed from random,
periodic, sinusoidal, and bounded uncorrelated sources.
• J11, U11
Spread Spectrum Clock (SSC) and residual Spread Spectrum Clock (rSSC)
generation.
• J12, U12
Option/Upgrade for automated jitter tolerance compliance tests. Use this test
to ensure that the jitter tolerance of the device under test complies with a
certain standard.
• J20
User-installable hardware module "Interference Channel" for simulating
intersymbol and sinusoidal interference.
• 003/U03
Option/Upgrade for half-rate clocking with variable duty cycle.
• A02
The symbol error ratio (SER) analysis allows error counting of coded, packetized
and retimed data streams. SATA and USB3 are popular examples of serial bus
standards using retimed loopback mode for receiver tolerance testing. SER
analysis includes the automatic handling of the running disparity of 8B/10B
coded patterns, filtering of up to 4 user-definable filler symbols, filtering without
any dead times up to 11.5 Gb/s data rates (12.5 Gb/s when using analyzer with
external clock), display of the error ratio as SER or calculated BER.
For PCIe3 (PCI® Express 3.0), the option A02 enables the error counter to ignore
changes in the length of 128/130 bit coded SKPOS (Skip Ordered Sets). To use
this functionality, N4903B software revision 7.40 or higher is required.
• 002
Option for N4876A 28 Gb/s Multiplexer 2:1, Second Output Channel and
M8061A 28 Gb/s Multiplexer with De-emphasis.
• A03/UA3
Option/Upgrade with analysis of 128b/132b coded patterns. To use option A03
functionality, the N4903B software revision 7.60 or later is required.
To check the options of your Serial BERT, press About in the Help menu. The
About dialog shows the installed options.
De-Emphasis Signal Converter
An external optional instrument which is used to convert the output of the pattern
generator to a de-emphasized signal, as required by many standards such as PCI
Planning the Test 1
Agilent J-BERT N4903B High-Performance Serial BERT 15

Express®, SATA 3 Gb/s, USB3, fully buffered DIMM, Hypertransport, CEI, or 10
GbE.
The following De-Emphasis Signal Converter can be used:
N4916A De-Emphasis Signal Converter
The N4916A is a 2-tap de-emphasis signal converter.
Following are the features and benifits of N4916A:
• Generates 2-tap de-emphasis
• Support data rates from 1 to 13.5 Gb/s
• Transparent to data jitter
• Small size
• Programmable via J-BERT N4903B or stand-alone
• USB and LAN connectivity
N4916B De-Emphasis Signal Converter
The N4916B is a 4-tap de-emphasis signal converter with optional clock multiplier.
It is intended to accurately characterize your multi-gigabit serial interfaces.
Following are the features and benifits of N4916B:
• Generates 4-tap de-emphasis with variable de-emphasis levels
• Supports data rates from 660 Mb/s to 10.5 Gb/s
• Tolerates non-balanced patterns
• Transparent to jitter
• Optional clock multiplier (Option 001)
• Small size
1Planning the Test
16 Agilent J-BERT N4903B High-Performance Serial BERT

• Programmable via J-BERT N4903B or stand-alone
• USB and LAN connectivity
Once the N4916A/B is connected, it can be conveniently controlled via the Serial
BERT.
N4876A 28 Gb/s Multiplexer 2:1
The Agilent's N4876A is a 2:1 multiplexer with an output data rate of up to 28.4
Gb/s.
Following are the features and benefits of N4876A:
• 2:1 multiplexer driven by Serial BERT data and aux data or by ParBERT Data
rate up to 28.4 Gb/s
• DC coupled, tolerates unbalanced patterns
• Transparent to Serial BERT generated jitter
• Small box, can be located closely to DUT
• Controlled via the local user interface of Serial BERT
• Remote Programming is transparently done via Serial BERT
M8061A 28 Gb/s Multiplexer with De-emphasis
The Agilent's M8061A is a 2:1 multiplexer to characterize serial interfaces of up to
28.4 Gb/s with optional de-emphasis to extend the rate of J-BERT N4903B pattern
generator.
Data rates up to 28.4 Gb/s are used for:
• Optical transceivers such as 100GBASE-LR4, -SR4 and -ER4, 32G Fibre Channel
• SERDES and chip-to-chip interfaces, such as OIF CEI
• Backplanes, cables, such as 100GBASE-KR4, -CR4
• Next generation computer buses, such as PCIe4
Following are the features and benefits of M8061A:
Planning the Test 1
Agilent J-BERT N4903B High-Performance Serial BERT 17

• 2-slot AXIe module that can be controlled from J-BERT N4903B user interface
via USB
• Expands data rate of J-BERT N4903B pattern generator up to 28.4 Gb/s
• Integrated and calibrated 4-tap de-emphasis, expandable to 8 taps
• Internal superposition of interference for common-mode and differential mode
• Transparent to jitter generated by J-BERT, Clock/2 jitter can be added
• Supports electrical idle
The Agilent M8061A is available with the following two options:
• Option M8061A-004 provides 4-tab de-emphasis feature
• Option M8061A-008 provides extension to 8-tab de-emphasis feature
These features are only operational when the respective options are installed
during manufacturing.
Navigating the Serial BERT GUI
Navigating the Serial BERT GUI - Concepts
The Serial BERT GUI provides a central launching point for its various controls. The
following picture illustrates the GUI layout of the Serial BERT.
1Planning the Test
18 Agilent J-BERT N4903B High-Performance Serial BERT

For understanding, the Serial BERT GUI can be divided into three panes; namely
the upper, middle and the lower pane.
The following picture illustrates the upper pane of the Serial BERT.
The upper pane provides access to the Navigation Menu which allows you to
launch the different controls and dialogs of the Serial BERT. For more information
on the Navigation Menu, refer to the section “How to use the Navigation Menu”
on page 21. In addition, this pane also displays the following controls, buttons
and indicators:
•BER Status Bar: Displays the calculated BER.
•Elapsed Time Indicator: Displays the progress of the current accumulation
period. If a measurement is running, it displays the measurement progress.
•Show Error Message Button: Displays error messages. The Show Error
Message button uses the following color codes to indicate different states:
•No error messages: The button will be in disabled state.
•New/unread errors: The triangle icon on the button will turn red.
•No new errors: The triangle icon on the button will remain yellow.
•Minimize Button: Minimizes the GUI to the Taskbar.
•Remote Indicator: If the GUI is in remote state, the remote indicator turns blue
and the mouse is catched within.
Planning the Test 1
Agilent J-BERT N4903B High-Performance Serial BERT 19
Upper Pane

•Control’s Title: Displays the title of the control window.
The following picture illustrates the middle pane of the Serial BERT.
The middle pane allows you to launch the different controls and dialogs of the
Serial BERT. These will be described in detail in the subsequent sections.
The following picture illustrates the lower pane of the Serial BERT.
The lower pane provides information about the Pattern Generator and the Error
Detector, this include:
• Setup information like Bit Rate and Selected Pattern.
•State information like Outputs ON or Jitter/ISI/SSC (Indicated by green LED).
• Error indicators like Error, Sync Loss, Data Loss, Clock Loss (Indicated by red
LED).
N O T E Two additional error indicators "Symb Lock" and "8b10b Error"will appear, if you
select the error ratio as 8B/10B Symbol Comparison from the Error Detector - Error
Ratio's window. For more details, see “Symbol Lock Indicator” on page 192 and
“8b10b Error Indicator” on page 192.
• Warning indicators like Output Protection (Indicated by orange LED at the
Outputs ON indicator).
• Temperatur warnings (Only visible if the temperature exceeds a certain
threshold value). For more information, see “Overheat Protection” on page
478.
1Planning the Test
20 Agilent J-BERT N4903B High-Performance Serial BERT
Middle Pane
Lower Pane