Question

Problem 6 Matlab: For a baseband message signal m(t) = 5cos(250t), and carrier signal c(t) = cos(2103t). Sketch the FM modulated signal in time domain in the interval (0, 0.1 seconds without using pmmod function in Matlab, for (a) kp = 7/2 rad/V (b) kp = 7/4 rad/V Verify and report your results using the MATLAB command pmmod, for different ky as mentioned above.

matlab is mathematics programing language.you have to write code of matlab, with your output screen shot of waveform

Answer 1

Matlab Script:

fc = 1000;
fs = 2*fc;
t = 0:1/fs:0.1;
kp1 = pi/2;
mt = 5*cos(2*pi*50*t);
FM1 = cos((2*pi*1000*t)+(kp1*mt));
subplot(211)
plot(t,FM1);
ylabel('FM without using pmmod');
title('k_p = \pi/2');

FM2 = pmmod(mt,fc,fs,kp1);
subplot(212);
plot(t,FM2);
ylabel('FM using pmmod');

kp2 = pi/4;
mt = 5*cos(2*pi*50*t);
FM1 = cos((2*pi*1000*t)+(kp2*mt));
figure(2);
subplot(211)
plot(t,FM1);
ylabel('FM without using pmmod');
title('k_p = \pi/4');

FM2 = pmmod(mt,fc,fs,kp2);
subplot(212);
plot(t,FM2);
ylabel('FM using pmmod');

output:

k = 12 FM without using prmod 16 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 FM using prmod 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1

ke=4 FM without using pmmod 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1 0.5 M MU FM using prmod 0 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.1