VeEX MTX150 Series, Руководство пользователя

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211 © VeEX Inc. All Rights Reserved. Fiber Channel
FC-1 BERT - Payload Setup
FC-1 Test Patterns
CRPAT sequence is offered for TX jitter measurements.
CRPAT and CJTPAT are available for RX jitter tolerance measurements - use these test patterns to test the
resilience of the receiver (Clock Data Recovery - CDR) and its tolerance to signals with jitter.
FC-2 Payload (test patterns)
Layer 2 "Compliant" test patterns are modified to resemble a true Fiber Channel frame - the pattern's format is
similar to a basic frame which includes a Start of Frame Delimiter (SFD), End of Frame Delimiter (EFD), and
Cyclic Redundancy Check (CRC).
Pseudo Random Bit Sequences (PRBS) are commonly used to test the signal integrity of high-speed links
and are defined in ITU-T 0.150 & 0.151 Recommendations – These legacy SONET/SDH/PDH test sequences
may appear random but they have specific properties that can be used to measure the quality of a link. PRBS
patterns can be normal or can be inverted.
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2E31-1: 147 483 647-bit pattern used for special measurement tasks, (e.g., delay measurements at
higher bit rates)
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2E23-1: 8 388 607 bit pattern primarily intended for error and jitter measurements at bit rates of 34
368 and 139 264 kbps
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2E15-1: 32 767 bit pattern primarily intended for error and jitter measurements at bit rates of 1544,
2048, 6312, 8448, 32 064 and 44 736 kbps
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2E11-1: 2047 bit pattern primarily intended for error and jitter measurements on circuits operating at
bit rates of 64 kbps and N x 64 kbps