M = 4;
alphabit = modem.qammod('M',  M ) ;             %QAM modulation
mod = transpose(modulate( alphabit , (0:M-1)));
avg = mod'*mod / M ;                % average power of constellation points
mod = mod / sqrt(avg);              % to make E[x^t x ] = 1
H = hadamard(4);   % The walsh code generation
H_use = H(:,2);  %using the second column for spreading.
S_coded = kron(mod,H_use);  % Spread the modulated data mod over the walsh code