Maximal-length binary sequences have been known for
a long time. They have many interesting properties, one of them
is that when taken in blocks of
consecutive positions they form
1 diÆerent codes in a closed circular sequence. This property
can be used for measuring absolute angular positions as the circle
can be divided in as many parts as diÆerent codes can be retrieved.
This paper describes how can a closed binary sequence with arbitrary
length be eÆectively designed with the minimal possible block-length,
linear feedback shift registers
(LFSR). Such sequences can be
used for measuring a speciØed exact number of angular positions,
using the minimal possible number of sensors that linear methods
CitacióFuertes, J.M., Balle, B., Ventura, E. Absolute type shaft encoding using LFSR sequences with prescribed length. "Preprints Centre Recerca Matemàtica (CRM)", Febrer 2006, núm. 665, p. 1-18.