An interleaved cascaded integrator-comb (“CIC”) filter receives an interleaved sensor output signal, including a plurality of digitized sensor signals at an input clock rate. An integrator of the interleaved CIC filter processes the interleaved signal to output an integrated interleaved signal. A downsampler of the interleaved CIC filter buffers portions of the integrated interleaved corresponding to a decimation rate for the interleaved signal. The portions of the signals are provided to a comb filter, which outputs a decimated interleaved signal.

Disclosed are an audio rate conversion system and an electronic apparatus. The audio rate conversion system includes an integrator-comb filter, a multi-rate filter and a first half-band filter, an input of the integrator-comb filter being accessed with digital audio data, an output of the integrator-comb filter being sequentially connected to the multi-rate filter and the first half-band filter; where, the integrator-comb filter is configured to reduce a rate of the digital audio data according to a preset decimation rate; the multi-rate filter is configured to convert a rate of digital audio data output by the integrator-comb filter into a rate of digital audio data corresponding to an accessed control signal according to the control signal; and the first half-band filter is configured to reduce a rate of digital audio data output by the multi-rate filter.

A digital signal processor is designed to channelize an input signal, and includes a channelizer circuit and a plurality of tuning modules. The channelizer circuit is designed to receive an input signal having a first bandwidth and to channelize the input signal into a first set of channels each having a bandwidth smaller than the first bandwidth as a first output signal and to channelize the input signal into a second set of channels having a bandwidth smaller than the first bandwidth as a second output signal. The plurality of tuning modules are designed to receive one or more channels from the first output signal or the second output signal and to further downsample the one or more channels to a user-defined bandwidth at a user-defined center frequency. Each of the plurality of tuning modules include a plurality of FIR filter blocks and a memory having a plurality of FIR filter coefficients.

A digital signal processor is designed to channelize an input signal, and includes a channelizer circuit and a plurality of tuning modules. The channelizer circuit is designed to receive an input signal having a first bandwidth and to channelize the input signal into a first set of channels each having a bandwidth smaller than the first bandwidth as a first output signal and to channelize the input signal into a second set of channels having a bandwidth smaller than the first bandwidth as a second output signal. The plurality of tuning modules are designed to receive one or more channels from the first output signal or the second output signal and to further downsample the one or more channels to a user-defined bandwidth at a user-defined center frequency. Each of the plurality of tuning modules include a plurality of FIR filter blocks and a memory having a plurality of FIR filter coefficients.

In a cascaded integrator comb (CIC) filter, a time-varying gain is added before the last integrating stage transforming its sub optimal boxcar impulse response into an FIR filter of arbitrary length. Make the coefficients sparse and taking them from a set of small integers leads to an efficient hardware implementation that does not compromise any of the essential CIC filter characteristics especially the overflow handling. The proposed sparse CIC structure can improve the worst case stop band attenuation by as much as 10 dB while occupying 77% of the chip area and consuming 30% less power compared to a standard a 5.sup.th order CIC filter, and reducing the overall bit growth of the filter and the amount of high rate operations. Design examples are given illustrating the advantages and flexibility of the proposed structure.

In a cascaded integrator comb (CIC) filter, a time-varying gain is added before the last integrating stage transforming its sub optimal boxcar impulse response into an FIR filter of arbitrary length. Make the coefficients sparse and taking them from a set of small integers leads to an efficient hardware implementation that does not compromise any of the essential CIC filter characteristics especially the overflow handling. The proposed sparse CIC structure can improve the worst case stop band attenuation by as much as 10 dB while occupying 77% of the chip area and consuming 30% less power compared to a standard a 5.sup.th order CIC filter, and reducing the overall bit growth of the filter and the amount of high rate operations. Design examples are given illustrating the advantages and flexibility of the proposed structure.

An interleaved cascaded integrator-comb (CIC) filter receives an interleaved sensor output signal, including a plurality of digitized sensor signals at an input clock rate. An integrator of the interleaved CIC filter processes the interleaved signal to output an integrated interleaved signal. A downsampler of the interleaved CIC filter buffers portions of the integrated interleaved corresponding to a decimation rate for the interleaved signal. The portions of the signals are provided to a comb filter, which outputs a decimated interleaved signal.