I had obtained the as follows in MATLAB.
xs = sqrt(1/2)*(randn(1,1)+1i*randn(1,1)); % transmitted signal of Complex Gaussian nature
x_1 = [xs xs 0 0 0 0 0 0 ]';
x_2 = [xs 0 xs 0 0 0 0 0 ]';
x_3 = [xs 0 0 xs 0 0 0 0 ]';
x_4 = [xs 0 0 0 xs 0 0 0 ]';
x_5 = [xs 0 0 0 0 xs 0 0 ]';
x_6 = [xs 0 0 0 0 0 xs 0 ]';
x_7 = [xs 0 0 0 0 0 0 xs ]';
x_8 = [0 xs xs 0 0 0 0 0 ]';
x_9 = [0 xs 0 xs 0 0 0 0 ]';
x_10 = [0 xs 0 0 xs 0 0 0 ]';
x_11 = [0 xs 0 0 0 xs 0 0 ]';
x_12 = [0 xs 0 0 0 0 xs 0 ]';
x_13 = [0 xs 0 0 0 0 0 xs]';
x_14 = [0 0 xs xs 0 0 0 0]';
x_15 = [0 0 xs 0 xs 0 0 0]';
x_16 = [0 0 xs 0 0 xs 0 0]';
xgssk = [x_1, x_2, x_3, x_4, x_5, x_6, x_7, x_8, x_9, x_10, x_11, x_12, x_13, x_14, x_15, x_16]