QNX in Automotive - Active Noise Control
Everyone wants a car with better fuel economy. In response, automakers have introduced fuel-saving techniques such as cylinder deactivation, low RPM torque converter lock-up, and balance-shaft removal. They are also making vehicles lighter by removing passive sound-dampening materials. These measures save gas, but also result in greater engine noise inside the vehicle cabin – noise that can cause driver fatigue.
To reduce engine noise, automakers use active noise control (ANC), which generates noise-cancelling signals that are played over loudspeakers in the vehicle cabin. The problem is, traditional ANC solutions use a dedicated hardware module, which makes them expensive to implement and unable to take advantage of the latest active control technologies.
At QNX, we have tackled this problem by creating a software-based ANC solution that can run on the car's infotainment head unit or audio amplifier. This approach not only reduces hardware costs significantly, but provides much greater flexibility and configurability.
QNX® Acoustics for Active Noise Control is a high-performance software solution designed to significantly reduce engine noise inside passenger vehicles. The solution is adaptive: it uses realtime engine RPM data to determine the frequencies to be cancelled, and microphone signals from the cabin to dynamically adjust for acoustic variations inside the vehicle. The system generates “anti-noise” signals that are emitted through the vehicle’s sound system, effectively cancelling the noise where the driver and passengers are sitting.
Today’s infotainment systems must accommodate an increasing number of audio tasks such as hands-free processing and voice recognition. Combining a software-based ANC solution with other audio processes on an existing processor or DSP enables tight audio integration; it also eliminates the need for dedicated hardware, thereby lowering bill of material costs and accelerating time-to-market.
QNX Acoustics for Active Noise Control integrates seamlessly into a vehicle's infotainment system to reduce engine noise caused by modern fuel-saving techniques.