Multirate algorithm for updating the coefficients

Adaptive linear combiner showing the combiner and the adaption process.k = sample number, n=input variable index, x = reference inputs, d = desired input, W = set of filter coefficients, ε = error output, Σ = summation, upper box=linear combiner, lower box=adaption algorithm.The adaptive linear combiner (ALC) resembles the adaptive tapped delay line FIR filter except that there is no assumed relationship between the X values.

Or they could be the outputs of multiple tapped delay lines.Adaptive filters are required for some applications because some parameters of the desired processing operation (for instance, the locations of reflective surfaces in a reverberant space) are not known in advance or are changing.The closed loop adaptive filter uses feedback in the form of an error signal to refine its transfer function.Before getting to the window, customers place their order by speaking into a microphone.