peb20954 Infineon Technologies Corporation, peb20954 Datasheet - Page 10

• Manufacturer Part Number: peb20954
• Description: Smart Integrated Digital Echo Canceller Sidec
• Manufacturer: Infineon Technologies Corporation

PEB 20954
PEF 20954
Introduction
VoIP Gateway
IP
Network
PSTN
SIDEC
(ATM,FR,
POTS
Ethernet)
PEB 20954
Figure 3
SIDEC in a Voice over IP Gateway
An emerging market in the telecom industry is “Voice Over IP”. Due to the long delay
echo cancellation is required. The delay is introduced through packetizing and voice
compression. The SIDEC handles different functions in a Voice over IP gateway, such
as Voice Detection, Voice Activity Detection, Comfort Noise and A-law u-law conversion
regarding G.711.
In a gateway the SIDEC points into the PSTN network as shown in Figure 3. The echo
itself is generated by the hybrid in the PSTN cloud. Before the voice signal from the
POTS gets packetized into ATM, FR or Ethernet cells the echo is being cancelled by the
SIDEC.
For a high voice quality in “Voice Over IP” environment echo cancellation is a major
requirement.
Preliminary Data Sheet
10
04.99