Questions
1
If the frequency response of an FIR system is given as H(z)=1-z-1-6z-2, then the system is ___________
Answer:Maximum phase
2
If the frequency response of an FIR system is given as H(z)=1-5/2z-1-3/2z-2, then the system is ___________
Answer:Mixed phase
3
A causal system produces the output sequence y(n)={1,0.7} when excited by the input sequence x(n)={1,-0.7,0.1}, then what is the impulse response of the system function?
Answer:[4(0.5)n-3(0.2)n]u(n)
4
A finite duration sequence of length L is given as x(n)=1 for 0≤n≤L-1 = 0 otherwise, then what is the N point DFT of this sequence for N=L?
Answer:X(k) = L for k=0 =0 for k=1,2....L-1
6
Which of the following is true regarding the number of computations requires to compute an N-point DFT?
Answer:N2 complex multiplications and N(N-1) complex additions
7
What is the DFT of the four point sequence x(n)={0,1,2,3}?
Answer:{6,-2+2j,-2,-2-2j}
8
If X(k) is the N point DFT of a sequence whose Fourier series coefficients is given by ck, then which of the following is true?
Answer:X(k)=Nck
9
What is the DFT of the four point sequence x(n)={0,1,2,3}?
Answer:{6,-2+2j,-2,-2-2j}
