Patent ID: 7010557

Claim:
A decimation system, comprising: a plurality of cascaded Finite Impulse Response (FIR) decimation filters, each of the FIR decimation filters having a transfer function H(z)=(1+z −1 ) N , where N is an integer; wherein each of at least two of the plurality of cascaded FIR decimation filters includes a polyphase FIR filter; wherein each of the polyphase filters is configured to receive a respective input signal, each of the polyphase filters including an input stage that generates a plurality of sub-sampled signals from the respective input signal; a plurality of parallel FIR decimation stages, each of the parallel FIR decimation stages for producing a respective decimated output signal component from a respective one of the plurality of sub-sampled signals; and a signal combiner for combining the plurality of decimated output signal components produced by the plurality of decimation stages, whereby the combiner produces a decimated output signal; wherein each of the parallel FIR decimation stages includes an FIR filter and a downsampler following the FIR filter.