What is bessel Thomson filter?

The Bessel-Thomson filter is a type of linear filter characterized by its maximally flat frequency response, which minimizes phase distortion. It is commonly used in applications requiring smooth signal processing, such as audio and communications systems. The filter design ensures that the group delay remains constant across the passband, making it suitable for preserving the waveform shape of signals. Its implementation typically involves a Bessel polynomial to achieve the desired frequency response characteristics.