Digital Lowpass Filters, basic questions

1. How does digital low-pass filter work?
2. Why do we use digital filters?
3. How do you find the transfer function of a low-pass filter?
4. Why digital filters are important in communication systems?

How does digital low-pass filter work?

A low-pass filter (LPF) is an audio signal processor that removes unwanted frequencies from a signal above a determined cutoff frequency. It progressively filters out (attenuates) the high-end above its cutoff frequency while allowing the low-end to pass through, ideally without any changes.

Why do we use digital filters?

Digital filters are used for two general purposes: (1) separation of signals that have been combined, and (2) restoration of signals that have been distorted in some way. Analog (electronic) filters can be used for these same tasks; however, digital filters can achieve far superior results.

How do you find the transfer function of a low-pass filter?

T(s)=K1+(sωO)

This transfer function is a mathematical description of the frequency-domain behavior of a first-order low-pass filter.

Why digital filters are important in communication systems?

One of the most important applications for digital signal processing in communications equipment is filtering. Filtering allows the selection of the desired signal and the rejection of unwanted signals and noise.