| 摘要 |
969,049. Vocoders. TELEFUNKEN PATENTVERWERTUNGS-.G.m.b.H. Nov. 30, 1961 [Nov. 30, 1960], No. 42827/61. Heading H4R. The pitch signal for a channel vocoder is derived by passing the speech signal from microphone 1, Fig. 2, through a 300 to 600 c.p.s. band-pass filter 27, amplitude limiter 28 and a filter 29 which passes only the fundamental component of the limited signal. At the receiver the pitch signal is added to a noise signal from generator 33 and the combined signal limited in limiter 32 and applied to the inputs of channel filters 10 to 15, the outputs from which are modulated by ring modulators 16 to 21 before being amplified and reproduced by reproducer 22. The channel signals and pitch signals are transmitted by a pulse code modulator. |
