isd-t360sb ETC-unknow, isd-t360sb Datasheet - Page 57

• Manufacturer Part Number: isd-t360sb
• Manufacturer: ETC-unknow

2—SOFTWARE
2.3.6
The Software Automatic Gain Control (SWAGC) algorithm can be activated with the compression algorithm or
with the Speakerphone algorithm. When used with the compression algorithm, it regulates the input signal to a
dynamic range that can provide higher compression quality. When used with the speakerphone algorithm, it
amplifies the input signal from the line to the speaker and this improves the quality for attenuated far end
speakers.
The SWAGC algorithm senses the energy level and updates the signal gain in order to amplify low energy sig-
nals and to avoid signal saturation. The SWAGC feature eliminates the need for an external hardware AGC, thus
reducing hardware costs and complexity. Hardware AGC may be used with the compression algorithm to
avoid signal saturation prior to sampling the signal. Note that the hardware AGC cannot be used with the
speakerphone algorithm.
A set of tunable parameters is available for controlling the SWAGC algorithm. Different values can be used for
the compression and speakerphone algorithms. The SWAGC may even be turned completely off for either one
of the algorithms. The way to use different tunable values is by updating the tunable parameter values prior to
activating each one of the algorithms. For more details on the SWAGC tunable parameters, see Table 2-4 in
the Command Description section.
ISD
SW AGC
Figure 2-6: SWAGC Characteristics with Default Tunable Parameter Values
Sound
Card
PC
+
JNM
JNR
JOM
JOR
JPM
JPR
JQM
JQM
Windows
IVS TOOL
.wav File
for
Figure 2-5: Creation of an IVS Vocabulary
Editor
JPR
JPM
Input Power (dBm @ 600 ohm)
Sentence
.wav Files
Number
JOR
Tables
.ini File
Table
JOM
JNR
IVS Compiler
JNM
JR
IVS Vocabulary
Compressed
Programmer
Files (.vcd)
ROM
ROM
Files
M
Command
INJ
Flash
ISD-T360SB
2-21