phase differenee的用法和樣例：
例句
- In practice there are three methods of accomplishing this phase difference.
在實踐中有三種方法來獲得相位差。 - A frequency tracking method is proposed.The synchronism sampling is achieved to improve the measuring precision of frequency and phase difference.
本文提出一種頻率跟蹤方法，可以在不過零開始採樣的情況下，實現整周期採樣，保證頻率和相位差測量的精度。
