Using a small acoustic microphone in the device, vibrations caused by a user scratching or tapping on a tabletop are detected and used as input signals.
After a white noise signal has been taken as the input of a standard sound source, a static acoustic test is conducted for a prototype silencer without air flow and at the normal temperature.
采用白噪声信号作为标准声源的输入信号，在常温无气流条件下对消声器实物模型进行了静态放声试验。
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Multi channel acoustic echo cancellation (AEC) systems suffer from the non uniqueness problem of the adaptive identification solution because of the correlation of the input signals.