基于信噪比估计和盒维数的调制信号识别

Modulation signals recognition based on SNR estimation and box dimension

针对数字调相和调频识别问题,提出采用调制信号绝对值的瞬时幅度的盒维数作为多进制数字相位调制(MPSK)和多进制数字频率调制(MFSK)信号类间识别的特征参数,并采用拟合曲线作为判决门限,该方法在保持具有较少的特征参数的同时还增强了对噪声的鲁棒性.在调制信号的类内识别中,分别采用MPSK信号的瞬时相位的盒维数和MFSK信号的瞬时频率的盒维数作为特征参数.仿真结果表明,在信噪比为5dB时,对信号进行完全识别的正确率可以达到90%以上,从而证明了该方法的有效可行性.

For digital phase modulation and frequency modulation recognition,the box dimension of the instantaneous amplitude of the modulated signals＇ absolute value is used as MPSK and MFSK signalscharacteristic parameter that can identify the modulated classes,and curve fitting is used as a decision threshold,this method not only keeps with fewer characteristic parameters but also enhances the robustness to noise.To identify the modulation signals in the class,the box dimension of the instantaneous phase of MPSK signals and the box dimension of the instantaneous frequency of MFSK signals are used as the characteristic parameters.The simulation results show that when the SNR（Signal-to-noise rate）is 5dB,the correct rate that the signal can be fully identified is more than 90%,which proves that the method is effective and feasible.