US 11,838,732 B2
Adaptive filterbanks using scale-dependent nonlinearity for psychoacoustic frequency range extension
Joseph Anthony Mariglio, III, Encinitas, CA (US)
Assigned to Boomcloud 360 Inc., Encinitas, CA (US)
Filed by Boomcloud 360 Inc., Encinitas, CA (US)
Filed on Sep. 9, 2021, as Appl. No. 17/471,012.
Claims priority of provisional application 63/222,370, filed on Jul. 15, 2021.
Prior Publication US 2023/0036487 A1, Feb. 2, 2023
Int. Cl. H04R 3/04 (2006.01)
CPC H04R 3/04 (2013.01) 24 Claims
OG exemplary drawing
 
1. A system, comprising:
a circuitry configured to:
generate quadrature components from an audio channel defining a quadrature representation of the audio channel;
generate rotated spectral quadrature components by applying a forward transformation that rotates a spectrum of the quadrature components from a standard basis to a rotated basis;
in the rotated basis:
isolate components of the rotated spectral quadrature components at target frequencies; and
generate weighted phase-coherent harmonic spectral quadrature components by applying a nonlinearity to the isolated components having a dependence on scale that is subject to constraints;
generate a harmonic spectral component by applying an inverse transformation that rotates a spectrum of the weighted phase-coherent harmonic spectral quadrature components from the rotated basis to the standard basis;
combine the harmonic spectral component with frequencies of the audio channel outside of the target frequencies to generate an output channel; and
provide the output channel to a speaker.