Extracting common signal without knowledge about noise [closed]

1. Which filter should be used to remove noise from a signal?
2. How do you identify noise in a signal?
3. Why is noise problematic for signal processing?

Which filter should be used to remove noise from a signal?

Some common filters used are Kalman filter, Recursive Least Square (RLS), Least Mean Square Error (LMS), Wiener-Kolmogorov Filters. Noise reduction can be achieved in both the time domain as well as frequency domain.

How do you identify noise in a signal?

Therefore, to ascertain the signal to noise ratio, one must find the quantifiable difference between the desired signal strength and the unwanted noise by subtracting the noise value from the signal strength value.

Why is noise problematic for signal processing?

Noise is an unwanted signal which interferes with the original message signal and corrupts the parameters of the message signal. This alteration in the communication process, leads to the message getting altered. It is most likely to be entered at the channel or the receiver.