The ASTATIC 901 is a superior low noise, electretcondenser cardioid surface mounted boundary microphone.
在无定向901是一个卓越的低噪音，表面贴装电容式心形话筒的边界。
2
The principle of electretcondenser microphone and its noise are analyzed in the paper. It will be helpful to improve the electric specification.
本文对驻极体电容传声器的原理及噪声作了分析，这将有助于提高它的电特性。
3
Theoretical evaluation and simulation experiments show that the improved BP neural network can effectively detect the image feature of electretcondenser microphone.