| 摘要 |
<p>PURPOSE: An Internet phone is provided to perform a conversation with a general telephone and a conversation with an other Internet phone through an Internet network and perform a conversation with a general telephone connected through a PSTN(Public Switched Telephone Network) and the other Internet phone connected through the Internet network. CONSTITUTION: An analog voice input and output device has a handset(10), a speaker phone(12), an external voice input and output connecting unit(14) connected with an external voice input and output device, and a multiplexer(16) for selectively converting the conversation of the handset(10), the speaker phone(12), the external voice input and output connecting unit(14). The first signal converting device has the first codec(18) for converting an analog voice signal inputted through the analog voice input and output device into a digital signal, and converts a digital signal from an encoding/decoding device into an analog signal. The encoding/decoding device has a DSP(20) for compressing and coding a digital voice signal inputted through the first codec(18), decompressing and decoding a compression encoding signal inputted through an MCU, generating a digital tone signal corresponding to a DTMF tone signal according to the control of the MCU, discriminating an inputted tone signal, and removing an echo sound.</p> |
