Description
Objectives:
Understand different concepts of ideal digital Filters
Prerequisites:
LTI Systems, DTFT-IDTFT, Sampling Theorem, Digital Frequency
Important notes:
Explore SINC function in Matlab, You need to use different Matlab function which you
have already make like impulse, signal addition, convolution etc.
Problems
1. Obtain the impulse response of
a) Ideal Low pass filter – Hlp(ω)
b) Ideal High pass filter – Hhp(ω)
SEAS Winter 2020
LAB 6
2
c) Ideal Band pass filter- Hbp(ω)
d) Ideal Band stop filter- Hbs(ω)
Steps to obtain impulse response of ideal digital filters :
Based on frequency response given above, obtains specifications for H(ω) for all four
filters.
After obtaining H(ω) for each filter. Take IDTFT for each filter type to obtain h(n)
Adjust h(n) in terms of “SINC” function
Create single matlab script and write h(n) equation for each filter type.
Plot h(n) for each filter type. Take h(n) range from n=-20 to n=20 (Truncated response).
Take = 1/6 , = 1/9, = 1/3
2. Let input signal x(n) = (
) (
) passes though ideal low pass and ideal
high pass filter by determining and .
Find y(n) (i.e. Convolution) in both case using your own function. Make sure that output
response is same as equation. Take = 1/12
This is the application of convolution for signal filtering.
