Digital Filters - FIR & IIR

The concept of linear phase characterises of DT-LTI has explained here. As these characteristics are very important to develop filters for the systems related to sound and many other systems for eg. Musical system, speech processing etc

Here you will understand Linearity and Time invariant property of DT- LTI system and importance of these properties. As most of real time systems like vocal system can be represented as DT-LTI system. Here you will also understand the relation between input, impulse response and output of DT-LTI system in time and frequency domain both.

In digital signal processing DT-LTI systems acts as a frequency selective filters i.e filtering various frequency components at it’s input. This nature of filtering action is determined by the frequency response characteristics H(w) i.e DT- LTI systems modifies the input signal spectrum X(w) according to it’s frequency response H(w). By proper selection of frequency response H(w) of DT-LTI system we can design Low pass filter, High pass filter etc.

Here you will understand the concept of filtering action and how to apply that concept in Digital signal processing

This lecture explains How DT-LTI can acts as FIR and IIR filter. Here your will understand whether to design FIR or IIR filter for particular application.

Always we are interested to develop causal and stable system. And importance of FIR filter(DT-LTI system) is ‘It has linear phase characteristics’ . To achieve linear phase, causality and stability of DT-LTI system( FIR filter) what should be location of poles and zeroes of the system. This section gives you complete idea about location of poles and zeros of the DT-LTI system to develop causal, stable and linear phase characteristics

Always we are interested to design causal, linear phase and real valued filter so it is necessary to understand  zeros which satisfices this condition so that we can design FIR filter with these zeros only

Understand condition of Linear Phase Characteristics of FIR filter and four different types of FIR filter.

Understand why some application strictly prefer FIR filter due it’s Linear Phase characteristics

This gives you clear idea about the principle of windowing technique in designing FIR filter

These steps helps you to design FIR filter in systematic and easy way

Different examples gives complete idea about the designing FIR filter with windowing technique. These designing examples tries to cover different variations in the designing statement.

This code includes detail explain about FIR filter filtering action. here we will understand the first generate a signal, check which frequency components are exits in the signal. Then generate a FIR filter according to the application requirement and filter the input signal through it. 

Here same above code extended for different types of filter, different window functions

Gives you clear idea about designing techniques method used for IIR filter.

As digital IIR filter designed by analog designing method, to get digital filter transfer function H(z) transformation techniques are required to map from analog(S-domain) to digital (Z-domain). IIM is one of the transformation technique used. In this lecture you will understand the principle used in IIM.

Explains what is aliasing effect and how it occurs in IIM

Gives complete derivation of formula of poles of Butterworth filter

Gives complete explanation about transfer function of Butterworth filter. It starts with one pole then two pole, three poles Transfer function of filter and then we are developing generalised formula for transfer function of the Butterworth filter which can be directly used in filter designing and makes the designing easy.

Here generalized transfer function for IIR filter has explained. This generalized transfer function can be used for both IIR filter Butterworth and Chebyshev filter.

Helps to design filter in a systematic and easy way

Understand the designing statement and how to design step wise in systematic way