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In the following tables, the supported Emulated FEC graph combinations are shown. Please note
that the SER measurement features covered in the Real FEC section are also supported on
Emulated FEC platforms.
Noise Injection and Shallow Loopback Measurements
Supported on the ML4039EN and ML4079EN.
With the ML4039EN and ML4079EN, you can realize noise injection to emulate real-life crosstalk
scenarios along with shallow loopback testing.
Noise implementation can be implemented in the form of a continuous interference, burst
crosstalk, or single shot noise.
In the following pictures, before and after noise injection on the PAM4 eye diagram is depicted.
Instant and Accumulated
Measurement Selection
Measurement Description
Pre-FEC Bit Error Rate
Raw and
unframed ratio of incorrect bits (Bit Errors/Total Bits) on a channel-
by-channel basis.
Post-FEC Bit Error Rate
Total number of bit errors remaining after emulated bit correction divided
by the total number of received bits.
Corrected Errors
Number of correctable bits determined by the error distribution algorithm in
the FEC emulator.
Block Count
Total number of bit stream blocks (emulated codewords) processed by the
emulation algorithm.
Error Count
Total number of PRBS errors captured by the error detector for a specific
test duration.
Saturated Block Count
Total number of emulated codewords that were determined to be
uncorrectable based on the distribution algorithm implemented by the FEC
emulator.
Symbol Error Rate Histogram
Calculated distribution of bit stream blocks sorted by numbers of symbol
errors per emulated block.
X axis
Y axis
Accumulated
Processed
Codeword
Count
Instant corrected Bit Error Count
Instant Processed Codewords Count
Instant Saturated FEC Blocks
Accumulated Corrected Error Count
Accumulated Saturated FEC Blocks
X axis
Y axis
Time
Instant Corrected Bit Error Count
Instant Processed Codeword Count
Instant Saturated FEC Blocks
Accumulated Corrected Bit Error Count
Accumulated Processed Codeword Count
Accumulated Saturated FEC Blocks
Table 7: Instant and Accumulated Emulated FEC Measurements
Figure
10
: About Window
Table 8: Emulated FEC axes Combinations
Figure
11
: About Window
