针对单通道双MFSK信号的调制识别问题,提出了一种基于经验模态分解(EMD)和分形盒维数的调制识别算法。该算法利用EMD将混有高斯噪声的双MFSK混合信号分解成多个分量,提取每个分量的分形盒维数作为特征参数,使用BP神经网络作为分类器对其进行识别。仿真结果表明,该算法对频谱不混叠的双MFSK信号有较好的识别效果。
According to the problem of modulation recognition of two MFSK signals in single-channel, a modulation recognition algorithm based on empirical mode decomposition(EMD) and fractal box dimension is proposed. Firstly, the algorithm uses EMD to decompose the two MFSK signals mixed with Gaussian noise into multiple components, then extracts fractal box dimension of each component as characteristic parameters, and BP neural network is employed as classifier to recognize them. The results of simulation show that the algorithm has better performance on two MFSK signals with the non-overlapping spectrum.