Impulse Response Estimation via Laguerre-Fourier Expansion

arXiv:2608.14769 2026 Architecture 1 ideas extracted · analyzed Sep 1, 2026

What the math gives to ML

The paper replaces direct frequency-domain deconvolution, which divides by potentially vanishing input spectra, with a Laguerre-Fourier coordinate system and a circulant FFT-solvable formulation. The transferable asset is not the system-identification application itself, but the use of a stable, structured basis for representing long causal impulse responses together with FFT-based convolution and explicit conditioning control. A promising neural-network adaptation is a causal sequence layer whose long convolution kernel is parameterized by a small number of Laguerre coefficients, optionally initialized or regularized using the input spectrum, rather than learning every lag independently. This can provide compact long-memory dynamics while avoiding unstable high-frequency or near-zero spectral directions.

Ideas from this paper

Unverified 2026

Laguerre Memory Convolution

Replace the length-L learned convolution kernel in a causal sequence layer with K Laguerre basis functions, where K is much smaller than L and the basis parameter controls the decay time scale. The layer retains a long receptive field but learns only K coefficients, while FFT or a fixed state-space realization evaluates the resulting convolution efficiently. This is especially appropriate for audio, sensor streams, and long-context regression where the desired impulse response is smooth or…

Useful6/10
Difficulty5/10
Novelty6/10
Paper: Impulse Response Estimation via Laguerre-Fourier Expansion arXiv:2608.14769