Method for rapid baseline recovery for irregular frequency content large dynamic range unipolar data signals

A method of filtering frequency-domain values, comprising:

• setting a filtering characteristic dynamically in response to a time-domain value of an amplitude of an output signal;
• filtering frequency-domain values of an input signal based on the dynamically-set filtering characteristic;
• wherein the filtering characteristic comprises a corner frequency, and filtering the frequency-domain values includes filtering out, via a high-pass filter, frequency components at frequencies lower than the corner frequency;
• wherein setting the filtering characteristic dynamically comprises changing the corner frequency dynamically from a first value to a second value, in response to the time-domain value of the amplitude falling below a threshold value having a first tolerance, the second value being greater than the first value;
• or
• setting the filtering characteristic dynamically comprises changing the corner frequency dynamically from a first value to a second value, in response to the time-domain value of the amplitude rising above a threshold value having a second tolerance, the second value being lower than the first value.