Automatic Gain Control (Agc); Voice Activity Detection (Vad); Vad Configuration; Comfort Noise Generation (Cng) - Yealink SIP-T3 Administrator's Manual

Automatic Gain Control (AGC)

Automatic Gain Control (AGC) is applicable to the hands-free operation and is used to keep audio output at nearly
a constant level by adjusting the gain of signals in some circumstances. This increases the effective user-phone
radius and helps with the intelligibility of soft-talkers.

Voice Activity Detection (VAD)

VAD can avoid unnecessary coding or transmission of silence packets in VoIP applications, saving on computation
and network bandwidth.
Topic

VAD Configuration

VAD Configuration
The following table lists the parameter you can use to configure VAD.
Parameter voice.vad
Description It enables or disables the VAD (Voice Activity Detection) feature.
Permitted
0-Disabled
1-Enabled
Values
Default 0
Web UI Settings > Voice > Echo Cancellation > VAD

Comfort Noise Generation (CNG)

Comfort Noise Generation (CNG) is used to generate background noise for voice communications during periods of
silence in a conversation.
Note : VAD is used to send CN packets when the phone detects a "silence" period; CNG is used to generate comfortable
noise when the phone receives CN packets from the other side.
Topic

CNG Configuration

CNG Configuration
The following table lists the parameter you can use to configure CNG.
Parameter voice.cng
Description It enables or disables the CNG (Comfortable Noise Generation) feature.
Permitted
0-Disabled
Values 1-Enabled
Default 1
Web UI
Settings > Voice > Echo Cancellation > CNG

Jitter Buffer

Yealink phones support two types of jitter buffers: fixed and adaptive. A fixed jitter buffer adds the fixed delay to
voice packets. You can configure the delay time for the static jitter buffer on the phones. An adaptive jitter buffer is
capable of adapting the changes in the network's delay. The range of the delay time for the dynamic jitter buffer
added to packets can be also configured on the phones.
Topic
<y0000000000xx>.cfg
<y0000000000xx>.cfg
Audio Features
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