Question 1
Marks : +2 | -2
Pass Ratio : 100%
What is the output sequence of the system with impulse response h(n)=(1/2)nu(n) when the input of the system is the complex exponential sequence x(n)=Aejnπ/2?
Explanation: First we evaluate the Fourier transform of the impulse response of the system h(n)
Question 3
Marks : +2 | -2
Pass Ratio : 100%
What is the magnitude of H(ω) for the three point moving average system whose output is given by y(n)=\\(\\frac{1}{3}[x(n+1)+x(n)+x(n-1)]\\)?
Explanation: For a three point moving average system, we can define the output of the system as
Question 6
Marks : +2 | -2
Pass Ratio : 100%
What is the response of the system with impulse response h(n)=(1/2)nu(n) and the input signal x(n)=10-5sinπn/2+20cosπn?
Explanation: The frequency response of the system is
Question 7
Marks : +2 | -2
Pass Ratio : 100%
What is the magnitude of the frequency response of the system described by the difference equation y(n)=ay(n-1)+bx(n), 0<a<1?
Explanation: Given y(n)=ay(n-1)+bx(n)
Question 9
Marks : +2 | -2
Pass Ratio : 100%
If h(n) is the real valued impulse response sequence of an LTI system, then what is the imaginary part of Fourier transform of the impulse response?
Explanation: From the definition of H(ω), we have
Question 10
Marks : +2 | -2
Pass Ratio : 100%
If h(n) is the real valued impulse response sequence of an LTI system, then what is the phase of H(ω) in terms of HR(ω) and HI(ω)?
Explanation: If h(n) is the real valued impulse response sequence of an LTI system, then H(ω) can be represented as HR(ω)+j HI(ω).