psb21381 Infineon Technologies Corporation, psb21381 Datasheet - Page 152

• Manufacturer Part Number: psb21381
• Description: Siemens Codec With S/t Transceiver
• Manufacturer: Infineon Technologies Corporation

Data Sheet
With speech, even if very strong resonances are present, the performance will not be
worsened by the high GDSAE needed. Only when speech is detected, a high reserve
prevents clipping. A time period ETAE [ms] after speech end, the parameters of the
comparator are switched to the “noise” values. If both sets of the parameters are equal,
ETAE has no function.
Description of the programmable parameters:
Parameter
GAE
GDSAE
PDSAE
GDNAE
PDNAE
ETAE
4.4.4.2
Principally, the SCLE works similarly to the SCAE. The formula of SCLE is the following:
Being in TX-mode, the speech comparator at the line side controls the switching to RX-
mode. When the SR-signal is higher than the SX-signal plus the expected/measured
echo return loss (VLE) and if SDR has detected speech, the comparator switches
immediately to RX-mode.
Speech Comparator at the Line Side (SCLE)
# of CRAM
Bytes
1
1
1
1
1
1
Range
– 48 to + 48 dB
0 to 48 dB
0.16 to 42 ms/dB
0 to 48 dB
0.16 to 42 ms/dB
0 to 1020 ms
if
SR > SX + VLE then RX
else TX
142
Comment
Gain of Acoustic Echo
Reserve when speech is detected
Peak Decrement
when speech is detected
Reserve when noise is detected
Peak Decrement
when noise is detected
Echo time
PSB 21381/2
PSB 21383/4
2001-03-12
Codec