PN.rar_Gold 码_pn序列生成_walsh 码_walsh扩频通信_扩频系统gold

function Wn=walsh(N); %WALSH Returns walsh codes of length N % Wn=walsh(N) % This returns a matrix of all the walsh codes of length N % N must be greater then 1 and a power of 2, e.g. 2,4,8,16,32.. % If N isn't a power of 2 then it is rounded up to the next power % of two. e.g. walsh(5) gives the same result as walsh(8); % % Example walsh codes. % For N = 2 % W2 = [ 1 1 % 1 0 ]; % % For N = 4 % W4 = [ 1 1 1 1 % 1 0 1 0 % 1 1 0 0 % 1 0 0 1 ]; % % Wn=walsh(N,'+-') returns the result as +- 1 e.g. % N = 2 % W2 = [1 1 % 1 -1]; % Copyright (c) Eric Lawrey July 1997 % Modified: % 9/7/97 Started coding the function. This function is finished % and tested to work. M = ceil(log(N)/log(2)); %find the power of 2 to match N, e.g. M=5 for N=32 if 2^M == 1, Wn = [1]; elseif 2^M == 2, Wn = [1 1; 1 -1]; else Wn = [1 1 1 1; 1 -1 1 -1; 1 1 -1 -1; 1 -1 -1 1]; for k = 1:M-2, Wn = [Wn Wn; Wn (-Wn)]; end end [m,n]=size(Wn); Wn=reshape(Wn,m*n,1);