OfficeServ 7100 PROGRAMMING
TECHNICAL MANUAL PART 2 MAY 2009
MMC: 835 MGI DSP OPTION
DESCRIPTION:
This MMC provides various MGI DSP options. These settings will apply to the 8 MGI
channels on board plus any MGI-16 installed in the system.
OPTION DESCRIPTION
AUDIO CODEC: Audio Coder / Decoder. Selects which audio compression will
be used. The default option is G.729A, which is the lowest
bandwidth setting. Other options are G.729, G.723, and
G.711 each with increasing bandwidth usage.
ECHO CANCEL: Echo Cancellation. When enabled this function removes echo
that is generated by voice reflection and packet delay.
DUAL-FLT EC: Dual Filter echo cancellation will perform a post-processing
on the audio stream after echo cancellation has been
performed. This setting determines the processing model to
use. The default setting of 8TRK2 MODE processes the
audio path as if it were received from an 8TRK2 card. Other
options are DISABLE, 8TRK MODE, and DTRK MODE which
processes audio as if it came from a PRI channel.
NLP: Nonlinear processing calculates ambient background noise
that s injected into the audio stream in place of packets lost
by echo cancellation. This setting determines the audio
dampening level to use for calculating background noise. The
default setting of 0 uses no dampening to maximize
conversation integrity. Other options are 1 and 2 and should
only be used when calls are known to have extremely noisy
backgrounds.
EC GAIN: This setting determines the audio gain for echo cancellation
processing. The default setting of 32 meaning audio will be
amplified by 3.2 dB. Valid settings are 18 (1.8 dB) to 38
(3.8dB)
EC TAIL LEN: During echo cancellation it is necessary to know the
acceptable length of an “echo.” This setting determines the
maximum length, in milliseconds, of the echo. The default
setting is 64 msec. Allowed values are any 8 msec interval
from 8 msec to 128 msec.