The QNX CAR acoustic processing module uses reference signals, and processes input and output signals to improve the sound quality and intelligibility of handsfree calls.
The figure below shows a simplified
view of handsfree acoustic echo cancellation through the QNX acoustic processing module:
- On the near-side (in the vehicle), one or more microphone signals are input for send-signal processing.
- The audio signal received from the far-side of the conversation is processed to improve sound quality before it is output to the local system.
- The send-signal processing produces an echo-free and noise-reduced output signal, which is sent to the remote system.
Figure 1. Input and output signals in handsfree telephony