论文信息 - A second-order oversampled sigma-delta modulator for bandpass signals

A second-order oversampled sigma-delta modulator for bandpass signals

A method of realizing sigma-delta modulation is presented that allows the noise spectrum to be shaped according to a chosen noise response weighting. The specific case of a second-order modulator having a noise null that can be located anywhere in the frequency range is derived. This can be advantageous since it allows the null to be located within the pass-band of band-pass signals such as speech. Applications could be possible, for example, to ADCs and DACs for higher frequency modulated-carrier signals.<<ETX>>

D. H. Horrocks

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