Voice Quality Enhancement (VQE) software is a critical component in the design of True Wireless Stereo (TWS) earbuds. TWS earbuds are equipped with a loudspeaker and multiple microphones.
Acoustic Echo Cancellation (AEC) software is required to remove the acoustic coupling caused by the close proximity of the loudspeaker and microphones. The design considerations are fairly straightforward for AEC in this VQE application.
The environmental acoustic noise picked up by the microphones requires a noise reduction (NR) solution. It has been well demonstrated that multi-mic noise reduction solutions provide better speech intelligibility and speech quality improvements over single microphone counterparts. Due to size and power constraints, two external microphones (per earbud) are typically deployed. As shown in, Microphone Array Beamforming Design, an endfire beamforming solution is recommended.
In addition, since earbuds are placed in the ear, there is an opportunity to use an accelerator as a bone-conduction microphone. As discussed in, Speech Enhancement Utilizing a Bone Conduction Microphone, the information provided by bone-conduction microphones can significantly improve the effectiveness of the VQE solution.
To put some finishing touches on the outgoing signal, Automatic Gain Control (AGC) and Equalization Filters are the final processing blocks.
The combination of these individual components into a Voice Quality Enhancement package creates a solution that provides superior audio quality for TWS earbuds. Please contact us to learn more.