What is a Band Pass filter that we code in Matlab? I need a good explanation about it. Also i have searched on the google but those were discussed about circuits and transistors. So i just need a good explanation about BandPass Filtering in Matlab and LowPass Filtering in MatLab. Thank you.
A lowpass filter is a "method/device" by which from an input signal series, only the lower frequencies present (up to a given threshold frequency) in the input are passed through.
A highpass filter is the opposite of a lowpass filter in that the higher frequencies (greater than a given threshold frequency) are passed through
A bandpass filter is a filter which passes through only a range ("band") of frequencies (between a low given threshold frequency and a high given threshold frequency)
MATLAB has functions to create any type of these filters (e.g http://www.mathworks.com/help/signal/ref/butter.html).
NOTE that there is not one unique method to create filters and various methods are used (e.g Butterworth, Chebyshev and so on), others are faster while others have nicer analytic properties and so on.
NOTE: If there is a more specific question abd filtering in MATLAB, can update answer to reflect that.