Nonlinear active noise control using spline adaptive filters

• ANC system based on a spline adaptive filter.
• Cascade of a linear and non-linear network.
• Non-linear network forms an adaptive activation function.
• Can handle various levels of nonlinearities.
• Enhanced noise cancellation over other schemes.

A spline adaptive filter (SAF) based nonlinear active noise control (ANC) system is proposed in this paper. The SAF consists of a linear network of adaptive weights in cascade with an adaptive nonlinear network. The nonlinear network, in-turn consists of an adaptive look-up table followed by a spline interpolation network and forms an adaptive activation function. An update rule has been derived for the proposed ANC system, which not only updates the weights of the linear network, but also updates the nature of the activation function. An extensive simulation study has been conducted to evaluate the noise mitigation performance of the proposed scheme and the new method has been shown to provide improved noise cancellation efficiency with a lesser computational load in comparison with other popular ANC systems.