pn.zip_PN generate_PN Order_generate pn code_it

function y=pn(m,v) % function y=pn(m,v) % m is the length of the shift register 2<m<21 % v selects from one of two possible independent codewords (v=1,2) % N. Chamberlain 1996. Optimized for speed. Note m>10 takes several minutes. if v==2 t3=[2,3]; t4=[3,4]; t5=[2,3,4,5]; t6=[1,2,5,6]; t7=[3,7]; t8=[2,3,4,8]; t9=[5,9]; t10=[7,10]; t11=[9,11]; t12=[2,10,11,12]; t13=[1,11,12,13]; t14=[2,12,13,14]; t15=[14,15]; t16=[1,5,14,16]; t17=[1,15]; t18=[1,12]; t19=[1,15,18,19]; t20=[1,18]; else t3=[1,3]; t4=[1,4]; t5=[2,5]; t6=[1,6]; t7=[1,7]; t8=[1,6,7,8]; t9=[4,9]; t10=[3,10]; t11=[2,11]; t12=[2,10,11,12]; t13=[1,11,12,13]; t14=[2,12,13,14]; t15=[14,15]; t16=[11,13,14,16]; t17=[14,17]; t18=[11,18]; t19=[14,17,18,19]; t20=[17,20]; end eval(['tt=t' num2str(m) ';']) ltt=length(tt); Q=ones(1,m); C=zeros(1,ltt); y=zeros(1,2^m-1); if ltt==2 % faster to use a do loop for checking parity Cs=[]; for kk=1:ltt; Cs=[Cs,' Q(tt(' num2str(kk) '))' ]; end Cs=['[' Cs '];']; for k=1:2^m-1; eval(['C=' Cs]) Q=[rem(sum(C),2), Q(1:m-1)]; y(k)=Q(m); end else for k=1:2^m-1; for kk=1:ltt; C(kk)=Q(tt(kk)); end Q=[rem(sum(C),2), Q(1:m-1)]; y(k)=Q(m); end end