Look-ahead delta sigma modulator having an infinite impulse response filter with multiple look-ahead outputs

摘要

A delta sigma modulator look-ahead IIR filter response can be divided into a natural response and a pattern response using superposition techniques. The look-ahead delta sigma modulators of the signal processing systems described herein include an infinite impulse response filter (“IIR”) that produces multiple output look-ahead natural responses to input signals having a look-ahead depth of “M”. The multiple output lookahead IIR filter reduces the amount of processing and memory used by the delta sigma modulator to generate quantizer output values. The multiple output lookahead IIR filter uses extended delay stages and modified feedback coefficients to concurrently produce multiple look-ahead natural responses. In one embodiment, the multiple output lookahead IIR filter concurrently produces M look-ahead natural responses.