ANR SIGNAL PROCESSING ENHANCEMENTS

摘要

An ANR circuit, possibly of a personal ANR device and possibly within an ADC of the ANR circuit, feedback reference data, feedforward reference data and/or pass-through audio data is provided to a secondary downsampling (and/or decimating) filter and/or is provided to a calculating block (e.g., RMS or absolute calculation block) to derive side-chain data to be output by the ANR circuit to a processing device coupled to the ANR circuit to employ the side-chain data in an analysis related to the provision of feedback-based ANR, feedforward-based ANR and/or pass-through audio by the ANR circuit. In an ANR circuit of a personal ANR device, a digital filter is structured to introduce one or more zeros to add gain to introduce positive phase in the provision of feedback-based ANR, wherein the gain follows a frequency-dependent "ski-slope" gain curve with little gain added at lower audible frequencies, with increasing gain that increases with frequency added at higher audible frequencies, and with the increasing gain flattening at frequencies above audible frequencies.