Abstract: A system for providing spectral compensation for vestigial sideband, VSB, signals with carrier frequency error. The VSB signal is sampled and digitized. The carrier frequency of the digitized signal is translated to a selected IF frequency. A fixed frequency VSB filter is then used to provide spectral compensation for the signal.

Abstract: A series of sigma-delta modulators are connected in a cascaded architecture. Each sigma-delta modulator has a noise transfer function that defines a unique set of quantization noise transmission zeros. A circuit is coupled to the cascaded architecture and has a signal transfer function that is an approximation of the noise transfer function of a first sigma-delta modulator in the series of sigma-delta modulators.

Abstract: A digital mixing to baseband decimation filter includes a mixer section and a low-pass filter section. The mixer section generates in-phase and quadrature signal components at baseband from low-resolution, high-rate digital data lying within a signal passband offset from baseband. The low-pass filter section transforms an incoming data stream to high-resolution, low-rate digital data. The mixer section can precede or follow the filter section.

Abstract: A band-pass sigma-delta modulator includes a translator for tuning to a selected signal passband within the tuning range of the modulator. In a network implementation, the translator is integral with each integrator associated with the sigma-delta modulator(s). The translator can comprise a network having a transfer function defined in the Z-domain as (Z.alpha.-1)/(Z-.alpha.), where -1.ltoreq..alpha..ltoreq.1 defines the tuning. The value of .alpha. is defined as .alpha..tbd.cos(2.pi.f.sub.gm /f.sub.s), where f.sub.gm is the geometric mean frequency of the passband and f.sub.s is the input sample frequency of the sigma-delta modulator(s). The invention can benefit many signal processing applications such as, for example, A/D, D/A and D/D converters; and digital communication systems including digital radio and digital TV. In digital communications (e.g., radio, TV, etc.