针对MPSK信号的调制识别问题,提出了一种新的基于二次方谱相关特征的识别算法。本文对MPSK信号二次方谱相关特性进行了推导和分析,并根据二次方循环谱特性提出了一种新的基于二次谱相关密度的归一化识别特征,新识别特征不受载波相位误差、信号幅度变化的影响,且特征提取方法简单、高效,有利于工程实现。最后对算法识别性能进行了仿真分析,仿真结果表明在低信噪比下该算法具有良好的识别性能,在高斯白噪声环境下,当信噪比为4dB时,正确识别率可达到95%以上。理论分析和仿真结果都证实了该算法的有效性和可靠性。
A new algorithm based on spectral correlation of the square of MPSK signals is proposed for recognition of MPSK. Firstly the theory of cyclic spectral is explained and analyzed by the paper,a class of new unitary characteristic parameters is proposed for the modulation recognition of MPSK signals from the expression of cyclic spectrum function,which is invariant with local carrier phase offset and amplitude scale of the base band MPSK signal.The method of feature extraction is very simple and efficient,and it is conducive to project implementation.Finally the algorithm is simulated by computer.Include the simulattion of recognition performance and the simulate of performance comparison with similar algorithms.The good performance in lower signal noise ratio(SNR) of the algorithm has been proved by the simulation results.In the gauss white nose channel(AWGN),simulation results show that the success rate of recognition is over 95%when the SNR is 4dB.Theoretical analysis and computer simulation prove the robustness and efficiency of the new recognition algorithm.