I want your help to know whats the features of HPF and LPF, and their applications area?
A high pass filter (HPF) allows the frequencies above a frequency, called the cut-off point, to pass while it attenuates the frequencies below the cut-off point. See: http://en.wikipedia.org/wiki/High-pass_filter
A low pass filter (LPF) does just the opposite, letting the low frequencies pass and attenuating the high frequencies. See http://en.wikipedia.org/wiki/Low_pass_filter
The low pass filter is often used to remove high frequency noise while allowing the low frequency signal to pass. There are zillions of other uses also
See this free book for more info:
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