Title :
A second-order oversampled sigma-delta modulator for bandpass signals
Author_Institution :
Sch. of Electr., Electron. & Syst. Eng., Univ. of Wales Coll. of Cardiff, UK
Abstract :
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
Keywords :
analogue-digital conversion; band-pass filters; delta modulation; digital filters; digital-analogue conversion; modulators; speech analysis and processing; ADCs; DACs; IIR filter; bandpass signals; modulated-carrier signals; noise; noise response weighting; noise spectrum shaping; second-order oversampled sigma-delta modulator; speech; Circuit noise; Delta-sigma modulation; Filtering theory; Filters; Frequency; Noise shaping; Quantization; Sampling methods; Speech; Systems engineering and theory;
Conference_Titel :
Circuits and Systems, 1991., IEEE International Sympoisum on
Print_ISBN :
0-7803-0050-5
DOI :
10.1109/ISCAS.1991.176709
