Sequence order

The sequence order determines the number of samples in the maximum length sequence (MLS). The number of samples in the MLS is given as 2^ (Sequence order) – 1.

When the MLS measurement method was first introduced, the maximum length sequence was generated using shift registers. By connecting the shift registers in a special way it was found that a maximum length sequence could be generated. This was the longest sequence that could be made before it repeated itself, and the length was given as 2^(# of shift registers) - 1. The Sequence order is the same as the number of shift registers used to generate the sequence. It was found that this sequence had very useful properties for measurements and it is still today used.