Hyundai developing road noise active cancellation tech
The industry-first system is said to create a "nearly silent" cabin environment.
Hyundai has announced a 'breakthrough' technology that uses active noise cancellation to reduce the level of road noise.
Known as Road Noise Active Noise Control (RANC), the system uses a microphone to pick up the sound of the air passing over the car and tires contacting the road surface. A digital signal processor then creates an inverted soundwave that is piped through the stereo system to attenuate the ambient road noise.
The technology is similar to Hyundai's existing Active Noise Control feature, however the current ANC tech is better suited to addressing constant engine noise that is more predictable. The upgraded RANC works much faster, analyzing the sound and emitting the inverted soundwave in just .002 seconds -- quick enough to attenuate road noise that takes around .009 seconds to reach the passenger. It also uses input from an acceleration sensor to further improve sound reduction performance.
After testing RANC with various road surfaces, vehicle speeds and seating positions, Hyundai achieved an in-cabin noise reduction of 3dB. The company says 3dB represents roughly half the noise level compared to vehicles without RANC, with separate noise-cancellation processing performed for the driver's seat, front passenger and rear seats.
The automaker is accurate in stating that a 3dB reduction cuts the sound energy in half. Human perception does not follow the same scale, however, and a 3dB difference is effectively the minimum change for someone to hear any difference. It would likely require a drop of around 10 dB for vehicle occupants to perceive a 50-percent change in cabin noise.
Hyundai says its RANC tech is particularly promising for hybrid or all-electric vehicles that do not suffer from powertrain noise, creating a "nearly silent" cabin experience. The technology will make its production debut in an upcoming Genesis model.