EXFO PSO-200 Optical Modulation Analyzer - Manual (Page 109)

Bit Pattern Analysis and the Gearbox
Optical Modulation Analyzer 101
Using PRBS or User-Defined Bit Patterns with the Gearbox
6. Select the Length of the PRBS pattern. Available values are all of the
form 2
n
-1. Each length corresponds to a unique bit sequence, which
will be used for all streams.
Note: Since PRBS sequences are shown in hexadecimal notation, most bit
sequences will be truncated to match the selected PRBS bit length.
7. For each stream listed, perform the following:
7a. Click to view the entire bit sequence in the Bit Pattern Editor
window (read-only), then click OK.
7b. On the Gearbox tab, enter an Offset value (in bits) if you want the
sequence to start at the n
th
bit/position, and select whether each
bit in the stream is inverted or not (0 becomes 1 and vice-versa).
8. Click Apply to confirm your settings, or OK to also close the window.
Byte count