一个PN序列发生器，大M序列，供参考学习，-A PN sequence generator, the M series, for reference study,

PN-Generaot based on linear shift registers.

PN_GEN: This is a matlab function generates the Pseudo Noise sequnece of length (N)according to Generation Polynom and input state. Inputs: G - Generation Polynom, Zin - Initial state of Shift register N - The length o