Configuring Automatic Gain Control (Agc); Configuring General Media Settings - AudioCodes Mediant 2000 User Manual

SIP User's Manual

12.4.2 Configuring Automatic Gain Control (AGC)

Automatic Gain Control (AGC) adjusts the energy of the output signal to a required level
(volume). This feature compensates for near-far gain differences. AGC estimates the
energy of the incoming signal (from the IP or PSTN, determined by the parameter
AGCRedirection), calculates the essential gain, and then performs amplification. Feedback
ensures that the output signal is not clipped. You can define the required Gain Slope in
decibels per second (using the parameter AGCGainSlop) and the required signal energy
threshold (using the parameter AGCTargetEnergy).
When the AGC first detects an incoming signal, it begins operating in Fast Mode, which
allows the AGC to adapt quickly when a conversation starts. This means that the Gain
Slope is 8 dB/sec for the first 1.5 seconds. After this period, the Gain Slope is changed to
the user-defined value. You can disable or enable the AGC's Fast Mode feature, using the
ini file parameter AGCDisableFastAdaptation. After Fast Mode is used, the signal should
be off for two minutes in order to have the feature turned on again.
Note:
The procedure below describes how to configure AGC using the Web interface:

To configure AGC using the Web interface:
1. Open the IPMedia Settings page (Configuration tab > VoIP menu > Media submenu
> IPMedia Settings).
2. Configure the following parameters:
•
'Enable AGC' (EnableAGC) - Enables the AGC mechanism.
•
'AGC Slope' (AGCGainSlope) - Determines the AGC convergence rate.
•
'AGC Redirection' (AGCRedirection) - Determines the AGC direction.
•
'AGC Target Energy' - Defines the signal energy value (dBm) that the AGC
attempts to attain.
3. Click Submit to apply your settings.
Note:
12.5

Configuring General Media Settings

The General Media Settings page allows you to configure various media parameters. For a
detailed description of the parameters appearing on this page, see ''Configuration
Parameters Reference'' on page 409.
Version 6.4
The AGC feature requires that the device be installed with the IP Media
Detectors Feature Key
The following additional parameters can be configured using either the EMS
or ini file:
•
AGCMinGain - Defines the minimum gain (in dB) by the AGC when
activated
•
AGCMaxGain - Defines the maximum gain (in dB) by the AGC when
activated.
•
AGCDisableFastAdaptation - Enables the AGC Fast Adaptation mode
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12. Media
November 2011