Pretty much all of Fall 2024

7th-Semester-Fall-2024/ECOMMS/exams/exam-1/problem-2.py

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+import numpy as np
+import scipy as sp
+import matplotlib.pyplot as plt
+
+A_c = 1
+
+f_1 = 500
+T_1 = 1/f_1
+omega_1 = 2*np.pi*f_1
+
+f_c = 20000
+T_c = 1/f_c
+omega_c = 2*np.pi*f_c
+
+def m(t):
+    return 2*np.cos(2*omega_1*t) + 3*np.cos(3*omega_1*t)
+
+def s(t):
+    return A_c*m(t)*np.cos(omega_c*t)
+
+f_s = 40*f_c
+T_s = 1/f_s
+t = np.arange(0,T_1,T_s)
+
+plt.plot(t,s(t))
+plt.plot(t,m(t))
+plt.show()
+
+S = sp.fft.fft(s(t))[35:45]
+f = t*f_s/T_1
+f = f[35:45]
+for i in range(len(f)):
+    print(f[i], S[i].real)
+
+plt.stem(f,S.real/1600)
+plt.show()
+