gusucode.com > UWB_matlab源码程序 > CP0702/cp0702_Gaussian_derivatives_10dB_bandwidth.m
% % FUNCTION 7.6 : "cp0702_Gaussian_derivatives_ % 10dB_bandwidth" % % Analysis of -10 dB of the first 15 derivatives of the % Gaussian pulse as a function of the shape factor % % 'smp' samples of the Gaussian pulse are considered in % the time interval 'Tmax - Tmin' % % The function receives as input: % 1) the minimum value of the shape factor 'alphamin' % 2) the increase step 'alphastep' % 3) the number of values to be investigated % 'N_alphavalues' % % The function computes the ESDs of % the first 15 derivatives of the Gaussian pulse for the % 'alpha' value received as input, and then evaluates and % plots the -10 dB bandwidth for each derivative % % Programmed by Luca De Nardis function cp0702_Gaussian_derivatives_10dB_bandwidth(... alphamin, alphastep, N_alphavalues) % ----------------------------------------------- % Step Zero - Input parameters and initialization % ----------------------------------------------- smp = 4096; % number of samples alpha = alphamin; % Gaussian pulse form factor Tmin = -4e-9; % lower time limit Tmax = 4e-9; % upper time limit threshold = -10; % threshold (in dB) used to compute % the bandwidth t=linspace(Tmin,Tmax,smp);% initialization of the time axis dt = (Tmax - Tmin) / smp; % sampling period for j=1:N_alphavalues factor(j)=alpha; for i=1:15 % ------------------------------------------- % Step One - Pulse waveform in the time domain % ------------------------------------------- derivative(i,:) =... cp0702_analytical_waveforms(t,i,alpha); derivative(i,:) = derivative(i,:) / ... max(abs(derivative(i,:))); % ------------------------------------------- % Step Two - Analysis in the frequency domain and % evaluation of -10 dB bandwidth % ------------------------------------------- [Ess,f_high,f_low,BW] = ... cp0702_bandwidth(derivative(i,:),dt,threshold); minus10dbBand(i,j)=BW; end % increase of alpha value for the next step alpha = alpha + alphastep; end % ----------------------------- % Step Three - Graphical output % ----------------------------- F=figure(1); plot(factor,minus10dbBand'); axis([2e-10 12e-10 1e9 6e9]); AX=gca; set(AX,'FontSize',12); X=xlabel('\alpha [s]'); set(X,'FontSize',14); Y=ylabel('-10 dB Bandwidth [Hz]'); set(Y,'FontSize',14); grid on derivebehaviour = {'Increasing differentiation order'}; text(7e-10, 3e9, derivebehaviour,'BackgroundColor',... [1 1 1]);