Yealink SIP-T52S Administrator's Guide

Administrator’s Guide for SIP-T2 Series/T19(P) E2/T4 Series/T5 Series/CP860/CP920 IP Phones
882
To configure VAD via web user interface:
1. Click on Settings->Voice.
2. Select the desired value from the pull-down list of VAD.
3. Click Confirm to accept the change.
Comfort Noise Generation (CNG)
Comfort Noise Generation (CNG) is used to generate background noise for voice
communications during periods of silence in a conversation. It is a part of the silence
suppression or VAD handling for VoIP technology. CNG, in conjunction with VAD algorithms,
quickly responds when periods of silence occur and inserts artificial noise until voice activity
resumes. The insertion of artificial noise gives the illusion of a constant transmission stream, so
that background sound is consistent throughout the call and the listener does not think the line
has released. The purpose of VAD and CNG is to maintain an acceptable perceived QoS while
simultaneously keeping transmission costs and bandwidth usage as low as possible.
Note
For example, A is talking with B.
A: VAD=1, CNG=1
B: VAD=0, CNG=1
If A mutes the call, since VAD=1, A will send CN packets to B. When receiving CN packets, B will
generate comfortable noise.
If B mutes the call, since VAD=0, B will not send CN packets to A. So even if CNG=1 (B), A will
not hear comfortable noise.
VAD is used to send CN packets when phone detect a “silence” period; CNG is used to generate
comfortable noise when phone receives CN packets from the other side.

Yealink SIP-T52S Specifications

General

Touchscreen	-
Display diagonal	2.8 \
Backlight display	Yes
Display resolution	320 x 240 pixels
Lines quantity	16 lines
Phonebook capacity	1000 entries
Number of VoIP accounts	12
AC adapter input voltage	100 - 240 V
Bluetooth version	2.1+EDR
Security algorithms	802.1x RADIUS, HTTPS, MD5
Ethernet LAN interface type	Gigabit Ethernet
USB 2.0 ports quantity	1
Ethernet LAN (RJ-45) ports	2
Mounting	Desk/Wall
Handset type	Wired handset
Product type	IP Phone
Product color	Black
Voice codecs	G.722, G.723, G.723.1, G.726, OPUS, iLBC
Volume control	Digital
Operating temperature (T-T)	-10 - 40 °C
Operating relative humidity (H-H)	10 - 95 %
Cables included	LAN (RJ-45)
Number of handles included	1 pc(s)
Front camera	No
Operating system installed	Linux

Weight and Dimensions

Depth	212 mm
Width	211.6 mm
Height	166.8 mm