Echo Cancellation
Reference Manual (SIP Version)
Mediatrix 1204
211
The following settings are available:
“Enabling Individual Codecs” on page 202
for more details.
Echo Cancellation
Echo cancellation eliminates the echo effect caused by signal reflections. An echo is a signal that has been
reflected or otherwise returned with enough magnitude and delay to be perceived. The echo cancellation is
usually an active process in which echo signals are measured and cancelled or eliminated by combining an
inverted signal with the echo signal.
You cannot disable echo cancellation on the Mediatrix 1204.
Furthermore, the Mediatrix 1204 has an additional correlator feature that automatically fine-tunes the echo
cancellation activity.
Comfort Noise
Comfort Noise (CN) defines how the Mediatrix 1204 processes silence periods information it receives.
During silence periods, the Mediatrix 1204 may receive CN packets containing information about background
noise. When enabling Comfort Noise Generation (CNG), those packets are used to generate local comfort
noise.
X
To enable Comfort Noise:
1.
In the
voiceIfMIB
, locate the
voiceIfTable
group.
2.
Define the type of comfort noise in the
voiceIfG711ComfortNoiseGenerationEnable
variable.
The following settings are available:
3.
Restart the Mediatrix 1204 so that the changes may take effect.
Table 135:
G.729 VAD Settings
Setting
Description
disable
G.729 uses annex A only. The Mediatrix 1204 does not send G.729 Annex B
comfort noise frames.
enable
G.729 annex A is used with annex B. The Mediatrix 1204 sends G.729 Annex
B comfort noise frames during silence periods.
Standards Supported
•
RFC 3389: Real-time Transport Protocol (RTP) Payload for
Comfort Noise (CN)
Note:
Comfort noise only applies to the G.711 and G.726 codecs. G.723 and G.729 CNG is not
configurable because it is part of the codec.
Table 136:
Comfort Noise Settings
Setting
Description
disable
CNG disabled.
whiteNoise
CNG enabled – white noise.
customNoise
CNG enabled – custom noise. More elaborated background noise that
sounds better than white comfort noise.
Содержание Mediatrix 1204
Страница 6: ...Mediatrix Telecom a Division of Media5 Corporation Reference Manual...
Страница 26: ...Preface About this Manual End User Technical Support xxvi Mediatrix 1204...
Страница 27: ...Installation and Web Page Configuration...
Страница 28: ...Page Left Intentionally Blank...
Страница 50: ...Chapter 1 Installation Verifying the Installation 24 Mediatrix 1204...
Страница 98: ...Chapter 4 Web Interface SIP Parameters SIP Authentication 72 Mediatrix 1204...
Страница 127: ...SNMP Configuration...
Страница 128: ...Page Left Intentionally Blank...
Страница 162: ...Chapter 8 IP Address and Network Configuration Ethernet Connection Speed 136 Mediatrix 1204...
Страница 170: ...Chapter 9 SIP Servers Presence Compositor Server 144 Mediatrix 1204...
Страница 174: ...Chapter 10 DNS SRV Configuration DNS SRV Oriented Settings 148 Mediatrix 1204...
Страница 196: ...Chapter 12 Configuration File Download Configuration File Example 170 Mediatrix 1204...
Страница 220: ...Chapter 14 Gateway Configuration Detecting a Far End Disconnect 194 Mediatrix 1204...
Страница 240: ...Chapter 16 Voice Transmissions User Gain 214 Mediatrix 1204...
Страница 288: ...Chapter 23 Telephony Attributes Delayed Hot Line 262 Mediatrix 1204...
Страница 294: ...Chapter 25 Quality of Service QoS VLAN 268 Mediatrix 1204...
Страница 298: ...Chapter 26 Syslog Daemon Syslog Daemon Configuration 272 Mediatrix 1204...
Страница 302: ...Chapter 27 Statistics RTP Statistics 276 Mediatrix 1204...
Страница 319: ...Appendices...
Страница 320: ...Page Left Intentionally Blank...
Страница 332: ...Appendix B Standard Hardware Information Warranty 306 Mediatrix 1204...
Страница 336: ...Appendix C Cabling Considerations RJ 11 Telephone Cable 310 Mediatrix 1204...
Страница 372: ...Appendix E Glossary Wide Area Network WAN 346 Mediatrix 1204...
Страница 390: ...Index W 364 Mediatrix 1204...