Hi all,
Please, can you explain me why I get two different results of Gaussian pulse Power Spectral Density? This two approaches should lead to the equivalent results but do not. I really dont know where I make mistake. Thank you very much. I also attached the source file. The code:
if true%
% GAUSSIAN PULSE PSD
fc = 2e9; % Center frequency
tc = gmonopuls('cutoff',fc); % Width of each pulse
fs=50*fc; % Sampling frequency
SegmentDuration = 2*tc;N = fs*SegmentDuration;t = -SegmentDuration:(1/fs):(SegmentDuration-1/fs); % Signal evaluation time
y = gmonopuls(t,fc); figure();plot(t,y)figure();periodogram(y, rectwin(length(y)), [], fs, 'oneside', 'power');hgcf = gcf;hgcf.Color = [1,1,1];mean_power = mean(y.^2);mean_power_dBm = 10*log10(1000*mean_power);%---------------------------------------------------------------------------------------------------------
fc = 2e9; % Center frequencyFs = 100e9; % Sampling frequencytc = gmonopuls('cutoff',fc); % Width of each pulset = 0:1/Fs:(4*tc-1/Fs); % Signal evaluation timex = pulstran(t,2*tc,@gmonopuls,fc);figure();plot(t,x)N = length(x);NFFT = 2^nextpow2(N);xdft = fft(x,NFFT);xdft = xdft(1:NFFT/2+1);psdx = (1/(Fs*NFFT)) * abs(xdft).^2;psdx(2:end-1) = 2*psdx(2:end-1);freq = 0:Fs/NFFT:Fs/2;figure();plot(freq,10*log10(psdx))grid ontitle('Periodogram Using FFT')xlabel('Frequency (Hz)')ylabel('Power/Frequency (dB/Hz)')end
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