Signal Filtering

There are discussed methods and systems for filtering an information input signal (11, 11a, x), divided into different update intervals, according to parameters varying with the update intervals, to obtain a filtered output signal (y, 15). A system (10) may comprise: - a first filter unit (12) to filter a first filter input signal (11, x) at least at an initial subinterval ( T l ) in a current update interval ( T ) to obtain a first filter output signal (y', 13), according to parameters associated to the preceding update interval, the first filter unit (12) being configured to change the parameters along at least the initial subinterval ( T l ) from a higher-filtering status to a lower-filtering status; and - a second filter unit (14) to filter a second filter input signal (13), at the initial interval ( T l ), according to parameters associated to the current update interval ( T ) to obtain a second filter output signal (15), the second filter unit (14) being configured to change the parameters along at least the initial subinterval ( T l ) from a lower-filtering status to a higher-filtering status. The first filter input signal (11) is based on the information input signal (x), the first filter output signal (13) is an intermediate signal (y'), the second filter input signal is based on the intermediate signal (y'), and the filtered output signal (y) is based on the second filter output signal (15).