R2511-HP MSR Router Series Voice Command Reference(V5)

81
Inde
x
Meanin
g
Value ran
g
e Remarks
5
Upper limit of the ratio of the second largest
energy level from the column frequency group to
COLMAX. The ratio must be lower than this limit
for the input signal to be recognized as a DTMF
digit.
–18 to –3 dB, with a
default of –9 dB
The smaller the value,
the higher the detection
specificity and the lower
the detection sensitivity.
6
Upper limit of ROW2nd/ROWMAX. An input
signal is recognized as a DTMF digit only when
ROW2nd/ROWMAX < 6.
–18 to –3 dB, with a
default of –3 dB
The smaller the value,
the higher the detection
specificity and the lower
the detection sensitivity.
7
Upper limit of COL2nd/COLMAX. The ratio must
be lower than this limit for the input signal to be
recognized as a DTMF digit.
–18 to –3 dB, with a
default of –12 dB
The smaller the value,
the higher the detection
specificity and the lower
the detection sensitivity.
8
Upper limit of the ratio of the maximum energy
level of two extra specified frequency points to
max (ROWMAX, COLMAX). The ratio must be
greater than this upper limit for the input signal to
be recognized as a DTMF digit.
–18 to –3 dB, with a
default of –12 dB
The smaller the value,
the higher the detection
specificity and the lower
the detection sensitivity.
9
Lower limit of the DTMF signal duration. The
duration of DTMF key tone must be larger than
this threshold for the input signal to be
recognized as a DTMF digit.
30 to 150
milliseconds, with a
default of 30
milliseconds
The larger the value, the
higher the detection
specificity and the lower
the detection sensitivity.
10
Frequency of the first extra frequency point
specified for detection.
In addition, it must be a frequency 100 Hz
greater than or less than the row and column
frequency pair.
300 to 3,400 Hz,
with a default of 300
Hz
N/A
11
Frequency of the second extra frequency point
specified for detection.
In addition, it must be a frequency 100 Hz
greater than or less than the row and column
frequency pair.
300 to 3,400 Hz,
with a default of
3,200 Hz
N/A
12
Lower limit of the amplitude of the input signal.
The average amplitude must be greater than this
threshold for the input signal to be recognized as
a DTMF digit.
0 to 700, with a
default of 375
The larger the value, the
higher the detection
specificity and the lower
the detection sensitivity.
Usage guidelines
The dtmf threshold command issues the thresholds for DTMF dial tone detection to the underlying layer
DSP, for the purpose of fine tuning detection sensitivity and specificity. Inside the DSP, a set of generic
default values have been configured. They are 1,400, 458, -9, -9, -9, -9, -3, -12, -12, 30, 300, 3,200, 375,
with their index being 0 through 12. Professionals can use this command to adjust the device when DTMF
digit detection fails. In normal cases, the defaults are adopted.
The configuration of the dtmf threshold command takes effect on all E&M interfaces on the same module.
Examples
# Set the DTMF threshold 9 for voice subscriber line 1/0.
<Sysname> system-view