Microphone arrays are one of the most advanced tools for improving speech quality. Most microphones have an omni-directional directivity pattern, so all desired and undesired sounds sources are picked up by the microphone equally. A microphone array utilizing beamforming effectively does quality enhancement implicitly by focusing a receiving radiation pattern in the direction of a desired signal. Microphone array beamforming results in reduced interference and improved quality of the captured sound.
There are many design considerations for microphone array beamforming, such as the number of microphones and the placement of the microphones. Sometimes the application or existing product design will dictate the microphone array and sometimes the microphone array is an open design. In these cases, VOCAL uses it’s experience across all areas of communications design to create systems specific to our customers needs. VOCAL engineers can consult with you on the optimal microphone placement that will be meet your product and application requirements. However, there are some general truths of beamforming microphone arrays that must be considered:
- Increasing the number of microphones increases the attenuation of ambient noise.
- The noise attenuation is dependent on the frequency and the angle of arrival of the signal.
- The geometry of the microphone arrays affects the shape of the beam pattern and where the ambiguities occur.
- Increasing the spacing of the microphones increases the attenuation of the noise until Nyquist criteria has been violated and spatial aliasing occurs.
Applications of Beamforming Microphone Arrays:
- Audio/Video Conferencing Systems
- Large Conference Rooms
- Huddle Rooms
- Preprocessor for Automatic Speech and Speaker Recognition (ASR) Engines
- Robot (Human/Machine) Interfaces
- Intercom Systems
- Doorbell/Gate Units
- Restaurant/Bank Drive-Thru Systems
- In-home/office Units
- Digital Hearing Aids
- Speech Diarization Applications
- Security / Surveillance Devices
- In-car Audio Systems
- VR/AR Headsets
- and many more …
- Customized Beamforming Algorithm Design
- Beamsteering and Direction of Arrival Estimation
- Source and Object Code Licensing
- Consultation on the Microphone Array Design
- Consultation on Hardware Component Selection
- Integration Support
- Testing and Performance Optimization Services
In addition to the microphone array beamforming, VOCAL’s Voice Quality Enhancement (VQE) System provides a complete voice enhancement solution to cancel echo and further reduce noise. VQE combines various algorithms together in such a way that maximizes speech enhancement, whether the far-end listener is a human or machine.