| 摘要 |
A telephone having a method and apparatus for increasing the intelligibility of the loudspeaker output and for echo cancellation. The telephone includes an intelligibility booster for processing a speech input signal to generate an intelligibility-enhanced signal. The intelligibility booster includes a reverberation signal path for generating a reverberation signal, a direct signal path for generating an attenuated direct signal corresponding to the input signal, and an adder for combining the reverberation signal and direct signal to generate the intelligibility-enhanced signal. The reverberation signal path includes an intelligibility-information emphasizer followed by a reverberation unit. In the preferred embodiment, the intelligibility information emphasizer is a high pass filter and/or compressor that generates an intelligibility-dense signal to generate the reverberation signal. The reverberation unit processes the intelligibility dense signal which includes a stream of reverberation sequences of weighted delay signals. The weighted delay signals of each reverberation sequence are weighted according to an exponential decay pattern and so that the time delays between weighted delay signals tend to increase over the reverberation period. In response to the intelligibility-enhanced signal, a loudspeaker outputs a speech sound wave having an artificial reverberation component corresponding to the reverberation signal. An echo canceller uses the intelligibility-enhanced signal in cancelling an echo component in a microphone signal generated by the microphone of the telephone. |
