On nonlinear filters involving transformation of the time variable

A new type of nonlinear filter, called the E-Filter, is introduced that involves a transformation of the independent variable of the input function. It is shown how an E-Filter can be designed to filter out superimposed "noise" on a signal leaving the large peaks of the signal unattenuated. Unlike a low-pass linear filter, the low-pass E-Filter is almost frequency independent and so does not effect the amplitudes of large sharp peaks of the signal. It can be shown that the E-Filter can be realized in real time and that a wide class of E-Filters have a filtering action which is independent at the D.C. level of the input signal.