Specifications

6
Equalization and advanced waveform analysis
(Option 201)
As bit rates increase, channel effects cause significant eye clo-
sure. Many new devices and systems are employing equalization
and pre/de-emphasis to compensate for channel effects. Option
201 Advanced Waveform Analysis will provide key tools to enable
design, test, and modeling of devices and systems that must deal
with difficult channel effects:
• Capture of long single valued waveforms. PatternLock
triggering and the waveform append capability of Option
201 enable very accurate pulse train data sets up to 256
megasamples long, similar to a very deep memory real-time
oscilloscope acquisition.
• Equalization. The DCA-J can take a long single valued
waveform and route it through a linear equalizer algorithm
(default or user defined) and display the resultant equalized
waveform in real time. The user can simultaneously view the
input (distorted) and output (equalized) waveforms.
• Interface to MATLAB
1
analysis capability. User can define a
measurement with a MATLAB script. Result can be reported
on oscilloscope results display.
• Automatic dispersion penalty analysis (such as transmitter
waveform dispersion penalty or TWDP). User-entered
MATLAB scripts used to automatically process waveforms and
determine penalty values.
Advanced amplitude analysis/RIN/Q-factor (Option 300)
In addition to jitter, signal quality can also be impacted by impair-
ments in the amplitude domain. Similar to the many types of jitter
that exist, noise, inter-symbol interference, and periodic fluctua-
tion can cause eye closure in the amplitude domain. Option 300
can be added to an 86100C mainframe (Option 200 must also
be installed) to provide in-depth analysis of the quality of both
the zero and one levels of NRZ digital communications signals.
Amplitude analysis is performed at a single button press as part
of the jitter mode measurement process.
• Measurement results are analogous to those provided for jitter
and include Total Interference (TI), Deterministic Interference
(dual-Dirac model, DI), Random Noise (RN), Periodic
Interference (PI), and Inter-symbol Interference (ISI)
• Tablular and graphical results for both one and zero levels
• Export of interference data to delimited text format
• Save/recall of interference database
• Interference frequency spectrum
• Bathtub curve display
• Q-factor (isolated from deterministic interference)
• Adjustable probability for total interference estimation
Relative Intensity Noise (RIN)
Relative Intensity Noise (RIN) describes the effects of laser inten-
sity fluctuations on the recovered electrical signal. Like amplitude
interference, excessive RIN can close the eye diagram vertically,
and therefore affect the power budget or system performance.
The DCA-J can measure RIN on square wave as well as industry-
standard PRBS and other patterns. In order to avoid having the
measurement influenced by inter-symbol interference, the instru-
ment searches the pattern for sequences of consecutive bits
(for example, five zeroes or five ones) and measures the random
noise and the power levels in the center of this sequence. When
a reference receiver filter is turned on RIN is normalized to a 1Hz
bandwidth. The user can also choose between RIN based on
the one level or on the optical modulation amplitude (RIN OMA
according to IEEE 802.3ae). RIN measurements require Options
001, 200, and 300.
1. MATLAB Software is available from Agilent with the purchase of a new
DCA-J as Option 061 or Option 062, depending on the Toolboxes you need.
MATLAB can also be purchased separately from The MathWorks, Inc.
(www.mathworks.com). If users wish to run MATLAB on the 86100C
mainframe, they must purchase MATLAB 2008a or an earlier version. Please
see www.agilent.com/find/matlab_oscilloscopes for more information.
Overview of Infiniium DCA-J
Features