noise canceling microphone meaning in Chinese

抗噪声传声器

Method for measuring the performance of noise discriminating and noise cancelling microphones
噪声识别和噪声消除扩音器的性能测量方法
The directional of microphone : the unidirectional and the noise canceling microphone have vents at the bottom ; oppositely , the omnidirectional microphone is completely sealed
麦克风指向性:麦克风背有有气孔的,就是有指向性或抗噪型的麦克风,完全密封的,就是全指向的麦克风