Voice Activity Detection (VAD)
From Zenitel Wiki
Voice Activity Detection (VAD) is a feature available for the IP Station range. Voice Activity Detection samples the peak amplitude detected at the microphone every 30 ms and converts it to dB. If the sampled amplitude is continously above a trigger amplitude for a set duration, then a DAK key is triggered.
User interface
The Voice Activity Detection configuration is done from the IP-station web interface at Advanced --> VAD. The following settings are possible to configure:
- Minimum amplitude (dBA): Choose the trigger amplitude.
- Minimum duration of audio (ms): Choose for how long the sampled amplitude must be above the "Trigger ampltiude" before triggering the DAK key.
- DAK key to activate: Choose which DAK key to trigger.
- Minimum time before reactivation (ms): Choose how long to wait before enabling VAD after triggering the DAK key.
- Report DAK key off after (ms): With this parameter it is possible to delay sending DAK key off for some time.
- VAD status: Choose whether to enable to disable VAD.
Notes:
- The sound pressure SPL is dropping by 6 dB (four times) for every doubling of the distance from the microphone.
- The audio detection is before the noise reduction circuit, so in case Noise Reduction is activated, noise will always cause the detector to trigger.
- The VAD is working only when the station is in idle. It will not work if the Station is for example in conversation or in conference. (Station software 2.2.3.1)
Software requirement
- IP Station software 01.09.3.0 or later.