| 摘要 |
A system is disclosed for processing speech signals to enable effective power increase in a device utilizing the said signals. The system includes means for filtering an AF electrical signal analog of the speech signal, to thereby provide an AF signal including a narrow passed band of frequencies. The output from the filtering means are provided to means for symmetrically clipping the said output, to provide a series of pulses of constant amplitude, the discontinuities of which coincide with the zero axis crossings of the original AF signal. Sufficient amplification is provided at the filtering means to assure that the signal proceeding to the symmetrical clipping means is of sufficient amplitude in relation to the clipping level to enable the foregoing result. Reshaping low pass filter means receive the output from the symmetrical clipping means and sinusoidally reshape the said pulses. The signal from the reshaping low pass filter is provided to an additional limiting or clipping circuit, the function of which is to remove discontinuities which have been generated from the reshaping low pass filter. This further reduces distortion, thereby increasing articulation and intelligibility.
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