import numpy as np import scipy as sp import matplotlib.pyplot as plt f_c = 1 f_m = f_c/4 f_s = 8E3 T_s = 1/f_s A_c = 1 omega_m = 2*np.pi*f_m omega_c = 2*np.pi*f_c # Time samples to 10 seconds at a samplig frequency of 8kHz t = np.arange(0,10,T_s) m = np.cos(omega_m * t) plt.subplot(311) plt.plot(t, m, label="$m(t)$") plt.ylabel("$m(t)$") D_p = np.pi D_f = np.pi # The phase modulated signal S_p = np.cos(omega_c*t + D_p*m) plt.subplot(312) plt.ylabel("$S_p(t)$") plt.xlabel("t (seconds)") plt.plot(t,S_p) # The time integral of the mesage signal M = np.sin(omega_m * t) / omega_m # The frequency modulated signal S_f = np.cos(omega_c*t + D_f*M) plt.subplot(414) plt.ylabel("$S_f(t)$") plt.xlabel("t (seconds)") plt.plot(t,S_f) plt.show()