基于Hilbert变换的数字鉴相器研究

The research on the digital phase detector based on Hilbert transform

利用Hilbert变换进行数字鉴相器的设计以避免过零检测获得较高测量精度,在Matlab环境下采用窗函数法和等波纹切比雪夫法设计了FIR型Hilbert数字滤波器并对数字鉴相器进行仿真实验,使用Stable32进行频率源的仿真和稳定度的计算,从而验证数字鉴相器的仿真结果。仿真结果证明等波纹切比雪夫法所设计的Hilbert数字滤波器较窗函数法设计的Hilbert数字滤波器有较好的性能,更能较好地提高相位的测量精度。

To obtain high measurement precision and avoid zero-crossing detection, a digital phase detector was designed using Hilbert transform. The FIR Hilbert digital filter has been designed by using both the window function method and the ripple Chebyshev method in the Matlab environment. Stability of frequency source was calculated using Stable32 to verify the simulation results of digital phase detector. The simulation results show that the Hilbert digital filter designed by the ripple Chebyshev method has better performance than that designed by using the window function, and can better improve the precision of the phase measurement.