Let us know about digital filter first let us learn about filtering. Filtering is the special part of the digital signal processing system. It can also remove unwanted part of the signal such as random noise.
Digital filter uses a digital filter processor, it is a specific characteristic that you need to pay special attention to. In general digital filter can be considered two types are known as IIR and FIR filter. In the both of recursive and non-recursive (FIR and IIR filter) in DSP, the algorithm can be implemented is based on DFT or differential equation.
In general analogue input signal must satisfy certain requirements, That will be converting an output digital signal into analogue signal form.
A system that performs the mathematical operation in signal processing on a sampled signal to reduce or enhance certain aspects of that signal is known as a digital filter. It is removed the unwanted parts of the signal.
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