maxlen.m

％ This program calculates radar ranges in a jamming environment. It works ％ with both Stand-off jam

% Binary Maximal Length Sequence Code
% Program Generates a Random Sequence
% ------------------------------------

clear;clc;

% Code Length and Feedback (m=2-7;9-11)

m=input('length=');                             
a=m-1;
if m==5;a=3;end;
if m==9;a=5;end;
if m==10;a=7;end;
if m==11;a=9;end;
l=2^m-1;

% Start sequence

x= eye(1,m);
z=x;

% Generate sequence of zero-ones

for j=1:l;
    for i=2:m;x(i)=z(i-1);x(1)=z(a)+z(m);end;
    if x(1)==2;x(1)=0;end;
y(j)=z(m);z=x;end;

% Convert to sequence of 1,-1

for i=1:l;
    if y(i)==0;y(i)=-1;end;
end;

% Plot correlation

t=1:2*l-1;zz=xcorr(y);
plot(t,abs(zz));grid;
xlabel('Time');
ylabel('Voltage Correlation');
title(['Binary Code Autocorrelation']);


% Display Sequence

b=input('Display Sequence Yes=1;No=0;  ');
if b==1;disp(y);end;


end