Hello friends, welcome to ECE Academy. In this lecture, let us understand the introduction to design of FIR filters. In signal processing, filter is a device that removes some unwanted features from the signal. Here, FIR represents finite impulse response.
So, we can say FIR filter is having impulse response which is finite. So, it is having a finite number of samples in impulse response. The output of FIR filter depends only on present and past value or present or past value of the input samples.
It has the major application where the linear phase is important. Linear phase which. which means the phase response of the filter is linear function.
The linear phase filter will preserve the shape of the input signal. This is very important in communication and medical images as the signal shape is very important in these fields. The major application of FIR filter is in the field of data transmission, speech processing, correlation processing and interpolation.
Now let us understand the characteristics of FIR filter. The impulse response of FIR filter is finite length. So that is why it is known as finite impulse response filter.
The non-recursive FIR filters are always stable. So non-recursive which means the values are not repeating. So non-recursive FIR filters are always stable. The undesirable phase distortion. that result due to the non-linear characteristics of the frequency response can be eliminated using FIR filter.
So, this is very important characteristics of FIR filter. It is possible to implement a recursive FIR filters which offer significant computational changes. If we say recursive FIR filter which means the current output depends upon the previous output. The effect of startup transient have a small duration in case of FIR filter.
Quantization noise can also be made negligible by realizing non-recursive filters. The noise which is due to quantization can also be made negligible by using non-recursive FIR filter. Now let us see the advantages of FIR filter. FIR filter. FIR filters are stable as it is non-recursive.
Since FIR filter are non-recursive, these filters are stable. The FIR filters can be realized in both recursive and non-recursive structures. The FIR filters can have exact linear phase. The design procedures are highly flexible to achieve any magnitude response in case of FIR filter.
These FIR FIR filters are low sensitive to quantization noise. So this is one of the major advantage. FIR filters can be efficiently realized in hardware.
These are few advantages of FIR filters. Now let us understand the disadvantage. The practical realization of FIR filters are complex. Compared to IAR filter, FIR filter require more filter coefficients to be stored. In case of FIR filter, the long duration impulse response requires large amount of processing.
If the impulse response is of long duration, then it requires large amount of processing. These FIR filters are comparatively costly because narrow transition band of FIR filters requires more arithmetic operations and it requires more time. requires hardware components. So it requires more hardware components compared to the IIR filter. This is about the introduction to FIR filters.
Hope you have understood the topic. Thank you.