Fixed Parameter: 
fs = 1e5;                       % Sampling rate (samples per sec)
Ts = 1/fs;                      % Sampling time
N = 102400 - 1;                 % Total number of samples
t_axis = (0:N-1)*Ts;            % Time axis (the same during the entire experiment)
f_axis = -fs/2:fs/N:fs/2-1/N;   % Frequency axis (the same during the entire experiment)
T_sq = 100*Ts;                  % The duration of the square pulse (an integer number of sampling times)


