Methods and apparatuses for signal analysis

This invention relates to an apparatus for estimating frequency properties as in the preamble of claim 1. Furthermore, the invention relates to an apparatus for estimating the spectrum of a signal as in the preamble of claim 7. The invention further relates to a signal recognition system, a data compression system and a signal improvement system device including such apparatuses and methods for performing functions of the apparatus. A basilar membrane model is used to receive an input signal including a target signal in step I. With successive further steps the target signal is filtered from the input signal. After the filtering the target signal can be used as an input for further processing, like for example signal recognition of data compression. The target signal can also be applied to a substantially reverse method to be obtain an improved or clean signal.