一种新的低信噪比下的数字调制识别方法

针对数字调制识别在低信噪比下的应用,提出一种新的基于瞬时信息的调制识别算法。该算法一方面提出采用小波滤波器对信号的瞬时信息进行消噪处理,提高了调制识别算法在低信噪比下的识别能力;另一方面利用已有算法的3个特征参数σ_ap、σ_aa、和σ_fa以及在已有算法基础上改进的3个新的特征参数Ra、Rp和Rf,简化了识别过程,改善了低信噪比下的识别效果。仿真结果表明,该算法在信噪比低到5dB时,也能达到95.4%以上的识别率。

New algorithm for digital modulation recognition under low SNR

A new digital modulation recognition method based on instantaneous information is proposed for the application under the low signal-to-noise ratio(SNR).On the one hand,de-noising of instantaneous parameters is optimized by a wavelet filter,which can improve the recognition ability under the low SNR;on the other hand,the existing three feature parameters σ_ap,σ_aa and σ_fa,are used,and three new parameters Ra,Rp and Rf are proposed based on the existing feature parameters,which can simplify the process and improve the recognition ability.Simulation result shows that the algorithm is quite practical because the recognition ability probability is over 95.4% even if the SNR is low to 5 dB.