The Fourier series of a signal x[n] and its coefficients X k are both periodic of the
Question:
(a) To find the x[n], 0 ¤ n ¤ N 1, given Xk, 0 ¤ k ¤ N 1, write a set of N linear equations. Indicate how you would find the x[n] from the matrix equation. There is duality in the Fourier series and its coefficients, so consider the reverse problem: how would you solve for the Xk given the x[n]?
(b) Let x[n] = n for n = 0, 1, 2, and 0 for n = 3, be a period of a periodic signal x[n] of fundamental period N = 4, use the above method to solve for the Fourier series coefficients Xk, 0 ¤ k ¤ 3. Use MATLAB to find the inverse of the complex exponential matrix.
(c) Suppose that when computing the Xk for the x[n] signal given above, you separate the sum into 2 sums, one for the even values of n, i.e., n = 0, 2 and the other for the odd values of n, i.e., n = 1, 3. Write an equivalent matrix expression for the Xk.
Step by Step Answer: