| 摘要 |
PURPOSE:To perform transmission with audio analysis and synthesis, by providing a pre-circuit which makes wave shape processing of signal tone before analytical processing of processed audio input signal and shaping the signal tone into a waveform possible for transmission. CONSTITUTION:When a signal tone comes from an incoming side exchanger 1, it is shaped with a waveform shaping circuit 4. The output is transmitted to an audio synthesizer 8 through a transmission line 7 for the data analyzed and encoded the same as the audio signal with an audio analysis circuit 6, and the synthesized output is transmitted to an outgoing side exchanger from a channel 9. On the other hand, at a signal tone reception section, the output of the channel 9 is connected to the outgoing side exchanger 12 directly at calling and to the side passing through an LPF10 at no-calling with a switcher 11. Thus, the output of the channel 9 is suppressed for harmonics with the LPF10 to be original signal sound. |
