其局限性则是对交流信号源要求较高，要求高稳定性、低噪声及低失真度；

The limit of this method is that the sine wave generator with high performance is necessary, especially the stability, the noise and distortion of generator.

youdao

但再次说这可能是我的信号源问题，我会交流会上确定是否。

But again, this could be my source and I will confirm this at the meet.

youdao