| 摘要 |
A network interface device may include an I/O unit configured to receive data packets from a packet network. A processing unit may be in communication with the I/O unit and be configured to identify data packets including data representative of DTMF signals, convert the data in the data packets into analog DTMF tone signals, and determine if power of the analog DTMF tone signals is below a threshold value. A digital to analog converter may be in communication with the processing unit and be configured to generate the analog DTMF tone signals based on the data in the data packets. A DTMF amplifier may be in communication with the processing unit and the digital to analog converter, where the processing unit may cause the DTMF amplifier to amplify the power of the analog DTMF tone signals in response to determining that the power of the analog DTMF tone signals are below the threshold value. |
