| 摘要 |
PURPOSE: A unified multi-function telephone is provided to reduce a telephone charge by utilizing an internet phone without a personal computer by use of a multi-function telephone having internet phone, general telephone and gateway functions. CONSTITUTION: In a unified multi-function telephone, a CODEC(11) processes voice compression and restoration, A/D conversion, D/A conversion, G.711 PCM conversion, volume adjustment, and analog switch functions through a handset(headset)(7) and a speaker phone(9). A digital signal processing part(12) supports ITU-T standard G.721, G.722, G723.1, G728 functions, and processes DTMF encoding/decoding, volume adjustment, volume activity detection(AVD), noise adjustment functions. The digital signal processing part(12) has a voice compression and restoration function. An MCU part(13) controls the digital signal processing part(12), a key input part(14), an MAC part(16,17) and a DDA part(19). A control program is stored in a read only memory so as to perform a telephone transmission/reception algorithm for an internet communication network connection and a voice communication.
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