Atec Acterna-JDSU-ANT-20SE - Manual (Page 17)

Additional measurement mode
± Transfer MTJ results:
An MTJ measurement is first performed. The measured amplitude
values can then be used automatically as generator values for the
JTF measurement.
The results can be displayed in tabular and graphical form.
The graphical display includes the standard tolerance masks specified
in T1.105.03 and GR-253 or G.735 to G.739, G.751, G.758. The
distance of the measurement points from the tolerance masks indicates
the degree to which the device under test meets the requirements of the
standard.
Tolerance mask violations during the measurement are indicated in the
numerical table.
Freely programmable tolerance masks
The existing tolerance masks for the ANT-20SE can be altered as
required to suit requirements that do not conform to specific
standards. The new values selected for jitter frequency and jitter
gain/loss are stored when the application is saved.
Automatic limit testing of Maximum Tolerable Jitter
(Fast Maximum Tolerable Jitter F-MTJ)
ANSI T1.403, T1.404, T1.105.03, Telcordia GR-253, GR-499,
ITU-T G.823, G.824, G.825, G.958
This extremely fast measurement tests the device under test for
conformance to the standard tolerance mask limits for maximum
tolerable jitter.
Jitter frequencies . . . . . . . . . . . . . . . . . . . . . . up to 10 fixed frequencies
corresponding to standard tolerance mask
Detection criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TSE (bit error),
code error, B2, B3, REI, RDI
Error threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 999 999 errors
Settling time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 to 99.9 s
The editable frequency/amplitude values are set sequentially and the
test pattern monitored for the permitted bit error count by the
receiver.
The result of each measurement is shown in a table as the status
message ªOKº or ªFAILEDº.
Automatic determination of
Maximum Tolerable Jitter, MTJ
ANSI T1.403, T1.404, T1.105.03, Telcordia GR-253, GR-499,
ITU-T G.823, G.824, G.825, G.958
The ANT-20SE automatically determines the maximum jitter
amplitude tolerated by the device under test at each jitter frequency.
Jitter frequencies . . . . . . . . . . . . . . . . . . 20 freely selectable frequencies
Detection criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . TSE (bit error),
code error, B2, B3, REI, RDI
Error threshold . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 999 999 errors
Settling time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 to 99.9 s
Gating time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 to 999 s
The maximum permissible jitter amplitude is determined precisely and
quickly using a successive method.
The ANT-20SE determines the exact limit value.
The method is derived from long experience in the performance of
jitter tolerance tests and is recognized by leading systems manu-
facturers.
The frequency/amplitude result pairs can be displayed in tabular and
graphical form.
The graphical display includes the standard tolerance masks.
The distance of the measurement points from the tolerance masks
indicates the degree to which the device under test meets the require-
ments of the standard.
Tolerance mask violations during the measurement are indicated in the
numerical table.
Freely programmable tolerance masks
The existing tolerance masks for the ANT-20SE can be altered as
required to suit requirements that do not conform to specific
standards. The new values selected for jitter frequency and amplitude
are stored when the application is saved.
Automatic pointer sequences for analyzing
combined jitter
(available with CATS Test Sequencer option)
Among other things, T1.105.03 defines various pointer sequence
scenarios for testing combined jitter (mapping and pointer jitter) at
network elements.
These sequences are normally selected manually and the jitter
measured. ANT-20SE allows simple automation of these sequences.
The entire sequence is started and the maximum pointer jitter
determined with a single key press. This saves considerable time spent
in setting up the test and executing the measurement.
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Figure 12: Maximum Tolerable Jitter testing.
Figure 11: Jitter transfer testing results.