A Computation-efficient Online Secondary Path Modeling Technique for Modified FXLMS Algorithm

TL;DR

This paper introduces a computation-efficient online secondary path modeling method that enhances the modified FXLMS algorithm's ability to adapt to time-varying secondary paths without destabilizing components, improving stability and noise reduction.

Contribution

It presents a mode-switching technique between adaptive ANC and online SPM, eliminating the need for auxiliary noise or extra filters, thus simplifying and stabilizing the system.

Findings

Effectively handles secondary path variations in simulations.

Improves stability and noise reduction performance.

Eliminates destabilizing components in ANC systems.

Abstract

This paper proposes an online secondary path modelling (SPM) technique to improve the performance of the modified filtered reference Least Mean Square (FXLMS) algorithm. It can effectively respond to a time-varying secondary path, which refers to the path from a secondary source to an error sensor. Unlike traditional methods, the proposed approach switches modes between adaptive ANC and online SPM, eliminating the use of destabilizing components such as auxiliary white noise or additional filters, which can negatively impact the complexity, stability, and noise reduction performance of the ANC system. The system operates in adaptive ANC mode until divergence is detected due to secondary path changes. At this moment, it switches to SPM mode until the path is remodeled and then returns to ANC mode. Furthermore, numerical simulations in the paper demonstrate that the proposed online technique effectively copes with the secondary path variations.