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What is step response of a filter?
The most straightforward way to implement a digital filter is by convolving the input signal with the digital filter’s impulse response. In this same manner, the step response is the output when the input is a step (also called an edge, and an edge response).
How a digital IIR filter is designed?
IIR filters are typically designed basing on continuous-time filter functions. Once the transfer function has been chosen, different filter structures allow to implement the filter, be it in hardware or in software.
Which is the last step in the IIR filter design process?
After the analog filter is designed, it is time to go through the last step in the digital IIR filter design process. It is conversion from analog to digital filter. The most popular and most commonly used converting method is bilinear transformation method. The resulting filter, obtained in this way, is always stable.
Where are the poles of the IIR filter?
The poles of the IIR filter transfer function must be located within the unit circle in order that filter is stable. Figure 3-2-7a illustrates zeros and poles of the transfer function of a stable IIR filter in the z plane. Transfer function zeros are denoted by small circles, whereas its poles are denoted by small crosses.
Why is the Z transform important for IIR filters?
The z-transform of the transfer function is of great importance for IIR filters. The location of poles in the z plane is used for testing stability of designed IIR filter. The poles of the IIR filter transfer function must be located within the unit circle in order that filter is stable.
What is the length of a circular IIR buffer?
One buffer would be used for input samples and another one for output samples. These are usually circular buffers whose length can be expressed as 2^n, which in this case means that the circular buffer is 4 = 2^2 in length. By complexity, the given IIR filter corresponds to a 6th order FIR filter.