The VNC-ALA CAO is created for Vehicle Noise Compensation and Automatic Level Adjustment (VNC-ALA) as a reference project. It implements level control so as to help the user to get a similar subjective experience regardless of the vehicle noise.
Vehicle Noise is known to be created by the engine, tires and wind. This needs to be compensated. The VNC-ALA feature does level control based on noise-related vehicle information such as speed, fan and roof status. With a local microphone input streaming cabin noise information, VNC-ALA processes audio content of entertainment and announcement, continuously calculates and adjusts the necessary gain offset for different frequency bands. Thereby the user is able to seamlessly listen to the sound system regardless of the ambient noise.
The VNC-ALA consists of three main building blocks, the ALA CAO, the VNC CAO, and the Noise Estimator.
VNC-ALA CAO has two variants.
VNC Variant uses no noise estimator module and mic input. This variant does not adjust gain based on cabin noise.
VNC+ Variant is based on noise estimator and mic input is used