以一个n次不可约多项式f(x)∈F_2(X)为特征多项式的线性移位寄在器所产生的周期序列,设为a=a_0 a_1…a_0,a_1,…,如所周知,除全0序列外,序列的周期c就是多项式f(x)在GF(2~n)内的周期(可乘阶)。这序列也构成此移位寄存器的e个状态的状态圈。当f(x)为本原时,c=2~n-1;除全0状态外,状态圈唯一。当f(x)为非本原不可约时, A periodic sequence generated by a linear shift register with an n-times irreducible polynomial f (x) εF_2 (X) as a characteristic polynomial is set as a = a_0 a_1 ... a_0, a_1, ... As is known, All 0 sequences, the sequence of periods c is the polynomial f (x) in the GF (2 ~ n) within the cycle (multiplicative). This sequence also constitutes the status loop for the e states of this shift register. When f (x) is primitive, c = 2 ~ n-1; except the all 0 state, the state of the ring only. When f (x) is non-primitive irreducible,