PSEUDONOISE SEQUENCE GENERATORS WITH THREE-TAP LINEAR FEEDBACK SHIFT REGISTERS

摘要

A PN linear recurring binary sequence generator is described. It comprises a linear feedback shift register of r stages with three-tap feedback logic. The three stages which are fed back are i, j and r, wherein ijr. The stages i, j and r are selected to correspond to the exponents of a tetranomial which includes either an (r-1)th degree or an (r-2)th degree primitive polynominal over GF(2) as a factor. The PN sequence length is 2r-1-1 or 2r-2-1 when the shift register is properly initialized.