On Hamming distance of partial M-sequence with application to absolute encoder

An absolute encoder having a magnetic bubble revolution counter is developed. The Hamming distance of a partial M-sequence code is described. It is shown that the Hamming distance of an M-sequence code is equal to the number of 1´s included in the successive k-tuple of an M-sequence, where k is the code length. Then the theoretical values of the Hamming distance of the partial M-sequence code are introduced. From the results of a computer simulation, it is shown that if the tuple length is long enough, a partial M-sequence can be used an an error correcting code for the magnetic bubble revolution counter