a)The frequency response of the system is calculated using the DFT of the impulse response sequence. The magnitude response, phase response, and group delay can be derived from the obtained DFT coefficients.
To calculate the frequency response of the system using the Discrete Fourier Transform (DFT), we can simply take the DFT of the impulse response sequence.
Given impulse response: h(n) = {1, -1/2, 2, -1/2, 1}, n = 0, 1, 2, 3, 4
The DFT of the impulse response can be calculated as follows:
H(k) = Σ[h(n) * exp(-j * 2π * k * n / N)], for k = 0, 1, 2, ..., N-1
where N is the length of the sequence (in this case, N = 5).
Let's calculate the DFT coefficients:
For k = 0:
H(0) = 1 * exp(-j * 2π * 0 * 0 / 5) + (-1/2) * exp(-j * 2π * 0 * 1 / 5) + 2 * exp(-j * 2π * 0 * 2 / 5) + (-1/2) * exp(-j * 2π * 0 * 3 / 5) + 1 * exp(-j * 2π * 0 * 4 / 5)
= 1 + (-1/2) + 2 - (1/2) + 1
= 3
For k = 1:
H(1) = 1 * exp(-j * 2π * 1 * 0 / 5) + (-1/2) * exp(-j * 2π * 1 * 1 / 5) + 2 * exp(-j * 2π * 1 * 2 / 5) + (-1/2) * exp(-j * 2π * 1 * 3 / 5) + 1 * exp(-j * 2π * 1 * 4 / 5)
= 1 + (-1/2) * exp(-j * 2π / 5) + 2 * exp(-j * 4π / 5) + (-1/2) * exp(-j * 6π / 5) + 1 * exp(-j * 8π / 5)
Similarly, we can calculate H(2), H(3), and H(4) by substituting the respective values of k.
The magnitude response can be obtained as |H(k)|, and the phase response can be obtained as arg(H(k)).
Group delay can be calculated by taking the derivative of the phase response with respect to the frequency.
b) Calculation of DFS coefficients:
Given h'(n) = {1, -1/2, 2, -1/2, 1, 0}, where n = 0, 1, 2, 3, 4, 5.
The DFS coefficients can be calculated using the formula:
C(k) = (1/N) * Σ[h'(n) * exp(-j * 2π * k * n / N)], for k = 0, 1, 2, ..., N-1
where N is the period of the sequence (in this case, N = 6).
Let's calculate the DFS coefficients:
For k = 0:
C(0) = (1/6) * (1 + (-1/2) + 2 - (1/2) + 1 + 0)
= (1/6) * (3)
For k = 1:
C(1) = (1/6) * (1 + (-1/2) * exp(-j * 2π / 6) + 2 * exp(-j * 4π / 6) + (-1/2) * exp(-j * 6π / 6) + 1 * exp(-j * 8π / 6) + 0)
Similarly, we can calculate C(2), C(3), C(4), and C(5) by substituting the respective values of k.
c) Calculation of the output signal using DFT:
Given input signal: x(n) = {1, 2}
To find the 5-point DFT coefficients of x(n), we can use the same DFT formula as mentioned earlier, but with N = 5:
X(k) = Σ[x(n) * exp(-j * 2π * k * n / N)], for k = 0, 1, 2, ..., N-1
where N is the length of the sequence (in this case, N = 2).
Let's calculate the DFT coefficients of x(n):
For k = 0:
X(0) = 1 * exp(-j * 2π * 0 * 0 / 2) + 2 * exp(-j * 2π * 0 * 1 / 2)
= 1 + 2
= 3
For k = 1:
X(1) = 1 * exp(-j * 2π * 1 * 0 / 2) + 2 * exp(-j * 2π * 1 * 1 / 2)
= 1 + 2 * exp(-j * π)
= 1 - 2
= -1
To find the output signal y(n), we can multiply the frequency response coefficients (H(k)) with the input signal coefficients (X(k)) in the frequency domain, and then take the inverse DFT (IDFT) to obtain the time-domain signal.
Let's calculate y(n):
y(n) = IDFT[H(k) * X(k)], for n = 0, 1, ..., N-1
where * denotes element-wise multiplication.
By substituting the respective values of k and taking the IDFT, we can obtain the output signal y(n).
Note: The DFT and IDFT calculations involve complex arithmetic and exponential calculations, which are not shown explicitly here for brevity.
a) The frequency response of the system is calculated using the DFT of the impulse response sequence. The magnitude response, phase response, and group delay can be derived from the obtained DFT coefficients.
b) The DFS coefficients of the periodic version of the impulse response sequence can be calculated using the DFS formula.
c) The DFT coefficients of the input signal can be obtained, and by multiplying them with the frequency response coefficients, and taking the inverse DFT, we can find the output signal using DFT methods.
Please note that the actual numerical calculations for the DFT, IDFT, and other operations have not been shown here for brevity, but they can be implemented using appropriate mathematical functions or programming tools.
To know more about Frequency , visit;
https://brainly.com/question/254161
#SPJ11