FM mod and demod using MATLAB commands.

Create FM demodulator from FM modulator using your own audio data. (Not handel.mat)

Plot the demodulated Spectrum for white Gaussian noise source (refer slides 4 6).

Demodulate the FM modulated signal. z = fmdemod(y); plot(t,x,'r',t,z,'ks') legend('Input Signal', 'Demod Signal') xlabel('Time (s)') ylabel('Amplitude') Source: https://www.mathworks.com/help/comm/ref/comm.fmmodulator-system-object.html 0.8 Input Signal O Demod Signal 0.6 0.4 0.2 Amplitude 0 M + -0.2 -0.4 -0.6 -0.8 -1 0 0.05 0.1 0.15 0.35 0.4 0.45 0.5 0.2 0.25 0.3 Time (s) FM baseband modulation on white Gaussian noise source fs = 1e3; ts = 1/fs; fd = 10; % White Gaussian noise t = (0:ts:5-ts)'; x = wgn(length(t),1,0); MOD = comm.FMModulator('SampleRate',fs,'FrequencyDeviation',fd); y = step(MOD,x); SA = dsp.SpectrumAnalyzer('SampleRate',fs,'ShowLegend', true); step(SA,[y]) Demodulate the FM modulated signal. z = fmdemod(y); plot(t,x,'r',t,z,'ks') legend('Input Signal', 'Demod Signal') xlabel('Time (s)') ylabel('Amplitude') Source: https://www.mathworks.com/help/comm/ref/comm.fmmodulator-system-object.html 0.8 Input Signal O Demod Signal 0.6 0.4 0.2 Amplitude 0 M + -0.2 -0.4 -0.6 -0.8 -1 0 0.05 0.1 0.15 0.35 0.4 0.45 0.5 0.2 0.25 0.3 Time (s) FM baseband modulation on white Gaussian noise source fs = 1e3; ts = 1/fs; fd = 10; % White Gaussian noise t = (0:ts:5-ts)'; x = wgn(length(t),1,0); MOD = comm.FMModulator('SampleRate',fs,'FrequencyDeviation',fd); y = step(MOD,x); SA = dsp.SpectrumAnalyzer('SampleRate',fs,'ShowLegend', true); step(SA,[y])