Patent ID: 7774395

Claim:
A digital filter having a finite impulse response, with the length of the impulse response corresponding at most to the duration of N input values, wherein the digital filter: receives a digital filter input signal and emits a filter output signal, which is n-times oversampled in comparison to the filter input signal, and comprises a means for storage of a plurality N of look-up tables, with n data values being stored per value in each look-up table for a plurality of k possible values of the filter input signal, and each data value being characteristic for the product of a coefficient of the impulse response, and a value of the input signal or a value which is dependent on this value of the input signal, wherein the output signal is formed from the data values comprises N paths, with the input of each of the N paths being driven by the filter input signal or by a delayed filter input signal, and each of the N paths in each case have a storage element for storage of one of the N look-up tables, wherein each storage element has an address input which is driven as a function of the filter input signal, and an output for emitting stored data values as a function of the signal at the address input, and comprises a counter with n counts for the address input drive.