idinput.jl

"""
    idinput(N, class = "prbs"; band = 1)

Create a input signal for a sys.id. experiment, currently only supports prbs signals.
"""
function idinput(N, class = "prbs"; band = 1)
    output = zeros(N)
    if lowercase(class) == "prbs"
        start = 0x02;
        a = start;
        for i = 1:N
            newbit = (((a >> 12) $ (a >> 3) $ (a >> 2) $ (a >> 0)) & 1);
            a = ((a << 1) | newbit) & 0x7f;
            output[i] = newbit
        end
        if band > 1
            output = repmat(output',band,1)[1:N]
        end
    else
        warn("Input class $class not supported")
    end


    return output
end