Parasitic Spectral Lines in High Speed Generation of Binary Maximum Length Sequences

Adding modulo-2 a binary maximum length sequence to its replica delayed by half the maximal length, N , results in the same sequence but at twice the bit rate. The error in the spectral density of the resulting sequence which is created by delaying the replica by (N/2) + \epsilon instead of N/2 is examined, and the analytical formulas are derived.