采用基于多相滤波的数字正交变换技术提取信号瞬时特征的方法

本文研究了通信信号瞬时特征的提取方法。采用中频直接采样、抽取和滤波的方法完成信号的正交分解,从而提取信号的瞬时包络和相位主值序列。利用信号相位去卷叠算法和线性规划法估计信号的去卷叠瞬时非线性相位,利用傅里叶变换的微分特性估计信号的瞬时频率。通过文中的方法可以有效估计信号的瞬时特征,将其运用于信号调制体制识别取得了较好的效果。

Extracting Instantaneous Characters of Signals Using Digital Orthogonal Transform Technology Based on Multiphase Filter

The method of extracting instantaneous characters of communication signals is studied.Instantaneous amplitude and phase main sequences of signals are extracted through sampling,decimating and filtering of Intermediate Frequency( IF) signal to complete orthogonal decomposition of signal. Using algorithms of phase unwrapping and linear programming to estimate unwrapped instantaneous nonlinear phase and using the differential character of Fourier transform to estimate instantaneous frequency of signal are described. These methods can efficiently estimate instantaneous frequency and achieve satisfying result in automatic identification of digital modulations.