18.327/1.
130: Wavelets, Filter Banks and Applications
Problem Set 1
Issued: SES #3 Due: SES #6
Matlab Exercises
Please submit your Matlab code and plots.
1. Consider a two channel
√ √perfect reconstruction
√ filter√bank (see pp. 103 in the text) with the analysis fil
ters h0 [n] = {1/ 2, 1/ 2} and h1 [n] = {1/ 2, −1/ 2}. Consider also a signal x[n] = {0, 1, −1, 2, 5, 1, 7, 0}.
(a) Find the corresponding dual(synthesis) filters f0 [n] and f1 [n].
(b) Find (and plot) the signals v0 [n], v1 [n] and x[n].
(c) Plot the zeros of the filters h0 [n], h1 [n], f0 [n] and f1 [n] (use zplane).
(d) Plot the frequency spectra of v0 [n] and v1 [n].
√ √
2. Repeat the previous problem for the filters h0 [n] = {−1, 2, 6, 2, −1}/(4 2)} and h1 [n] = {1, −2, 1}/(2 2).
Textbook Problems
1. Problem Set 1.3, pp. 15. Problems 1 and 3.
2. Problem Set 1.4, pp. 21. Problems 9 and 11.
3. Problem Set 3.3, pp. 100. Problems 2 and 7.
4. Problem Set 4.1, pp. 113–114. Problems 3, 4, 9 and 12.