A CLASS OF PREDICTIVE ANALOG FILTERS FOR SENSOR SIGNAL-PROCESSING ANDCONTROL INSTRUMENTATION

A class of analog continuous-time filters is introduced, having predic tive properties for specified narrow-band signal models, such as low-o rder polynomials or sinusoids. Such filters are designed by using mode l transfer functions designed in the discrete-time domain. Z-to-s-doma in mapping is done using the inverse bilinear transformation. The anal og filters are implemented with active-RC structures, using the state- variable structure for biquads and a single-op-amp structure for real poles and zeros. The application examples include a filter for zero-cr ossing detectors, polynomial predictors for sensor signal smoothing, a nd an optimized sixth-order ramp-tracking filter for anti-aliasing and anti-imaging in digital signal processor (DSP) systems where high sel ectivity is required.