pn.m

来自「basic_cama 基本的CDMA仿真程序」· M 代码 · 共 22 行

function [seq]=pn(generator)
% genrate m-sequence
% generator从左到右，x的幂次从小到大
% generator=[1 1 0 0 1]表示f(x)=1+x+x^4
% 127阶 generator=zeros(1,8);a=[1,4,8];generator(a)=1;
% 255阶 generator=zeros(1,9);a=[1,3,4,5,9];generator(a)=1;
% 511阶 generator=zeros(1,10);a=[1,5,10];generator(a)=1;
connections(1:length(generator)-1)=generator(2:length(generator));
% connections=[1 0 0 1];
m=length(connections);
L=2^m-1;
registers=[1 zeros(1,m-1)];
seq(1)=registers(m);
for i=2:L
    new_reg(1)=mod(sum(connections.*registers),2);
    for j=2:m
        new_reg(j)=registers(j-1);
    end
    registers=new_reg;
    seq(i)=registers(m);
end