Our decomposition model solves the inverse problem as fol-
lows: decompose a signal into a given number of modes, either
exactly or in a least squares sense, such that each individual
mode has limited bandwidth. We assess the mode’s bandwidth
as the squared H1 norm of its Hilbert complemented analytic
signal with only positive frequencies, shifted to baseband
by mixing with a complex exponential of the current center
frequency estimate. The variational problem is solved very
efficiently in a classical ADMM approach: The modes are
updated by simple Wiener filtering, directly in Fourier domain
with a filter tuned to the current center frequency, then the
center frequencies are updated as the center of gravity of the
mode’s power spectrum, and finally the Lagrangian multiplier
enforcing exact signal reconstruction is updated as dual ascent.