Method And Apparatus For Nonlinear Filtering And For Mitigation of Interference

An apparatus for signal filtering converting an input signal into an output signal, wherein said input signal is a physical signal and wherein said output signal is a physical signal, the apparatus comprising:

• a) a means to establish a lower fence and an upper fence for said input signal, wherein said lower fence and said upper fence form a robust range that effectively excludes outliers of said input signal, and wherein an average of said lower fence and said upper fence represents a measure of location of said input signal;
• b) a depreciator characterized by said lower fence, said upper fence, said average, and a difference response and operable to receive a depreciator input and to produce a depreciator output, wherein said depreciator output is not larger than said average when said depreciator input is smaller than said lower fence, wherein said depreciator output is not smaller than said average when said depreciator input is larger than said upper fence, wherein said difference response is the difference between said depreciator input and said depreciator output, wherein said difference response is an increasing function of said depreciator input, and wherein said difference response is effectively zero when said depreciator input is within said robust range;
• wherein said depreciator input is effectively equal to said input signal and wherein said output signal is proportional to said depreciator output.

A digital signal processing apparatus comprising a digital signal processing unit configurable to perform one or more functions including a filtering function transforming an input signal into an output filtered signal, wherein said filtering function comprises:

• a) a robust range function operable to establish a lower fence and an upper fence for said input signal, wherein said lower fence and said upper fence form a robust range that effectively excludes outliers of said input signal, and wherein an average of said lower fence and said upper fence represents a measure of location of said input signal;
• b) a depreciator function characterized by said lower fence, said upper fence, said average, and a difference response and operable to receive a depreciator input and to produce a depreciator output, wherein said depreciator output is not larger than said average when said depreciator input is smaller than said lower fence, wherein said depreciator output is not smaller than said average when said depreciator input is larger than said upper fence, wherein said difference response is the difference between said depreciator input, and said depreciator output, wherein said difference response is an increasing function of said depreciator input, and wherein said difference response is effectively zero when said depreciator input is within said robust range;
• wherein said depreciator input is effectively equal to said input signal and wherein said output signal is proportional to said depreciator output.