Configuring DTMF tone detection
Perform this task to configure the threshold parameters and sensitivity level for DTMF detection.
The threshold parameters are used to determine whether a DTMF tone is valid. The system calculates the spectrum shape of input DTMF signals and matches the spectrum shape with the threshold parameters. A DTMF tone is considered valid if it matches all threshold parameters.
The sensitivity level is a trade-off between detection sensitivity and reliability. A higher DTMF detection sensitivity reduces the possibility of missing a true DTMF tone but increases the possibility of false detection. A lower DTMF detection sensitivity reduces the possibility of false detection but increases the possibility of missing a true DTMF tone.
To configure DTMF tone detection:
Step | Command | Remarks |
|---|---|---|
1. Enter system view. | system-view | N/A |
2. Enter voice interface view. | subscriber-line line-number | N/A |
3. Configure the threshold parameters for DTMF tone detection. | dtmf threshold analog index value | By default, indexes 0 to 12 correspond to 1400, 458, -9, -9, -9, -9, -3, -12, -12, 30, 300, 3200, and 375, respectively. This command is used by professional personnel to adjust the device in the case of DTMF tone detection failure. Typically, the default value is used. |
4. Set the DTMF tone detection sensitivity level. | dtmf sensitivity-level { high | low | medium [ frequency-tolerance value ] } | By default, the DTMF tone detection sensitivity is low. For the command and hardware compatibility, see Voice Command Reference. |