Aju Business Daily

SEOUL -- South Korea's Hyundai auto group has developed a new active noise control system that enables a nearly silent cabin environment by analyzing various types of noise such as resonant sounds created between tires and wheels or rumble sounds coming up from the road to produce inverted soundwaves.

Vehicle interior noise primarily comes from powertrain, road and wind. Hyundai Motor said Monday that its Road Noise Active Noise Control (RANC) system significantly reduces road noise and creates a serene cabin for electric and fuel cell electric vehicles. 

"RANC is a remarkable technology which takes existing NVH (noise, vibration and harshness) technology to the next level," Lee Gang-deok, a researcher of Hyundai's NVH Research Lab, was quoted as saying. "We will continue to take the leading position of NVH technology and deliver the highest level of quietness to customers."

The auto group has completed domestic and American patent applications about the location of sensors and signal selection method, the core technology of RANC. The technology will be applied to an upcoming Genesis model.

The existing method involved sound insulations and dynamic dampers, which increase weight and fail to block the buzzing infrasound completely. Using an acceleration sensor, RANC calculates vibration from the road and a control computer analyzes road noise.

Hyundai Motor said that it only takes 0.002 seconds to analyze the noise and produce an inverted soundwave, generated by the digital signal processor (DSP). RANC conducts accurate noise analysis and rapid computation to combat road noise for the driver's seat, the passenger seat and rear seats separately.

RANC reduces in-cabin noise by three decibels and potentially decrease the amount of unsprung weight, utilizing fewer sound-insulating parts and dampers, the group said.