低信噪比下DVB-S2信号的调制类型识别  

Modulation recognition of DVB-S2 signal at low SNR

作　　者：吴强[1] 王长生 谢李晋[3] 管立新[2] WU Qiang;WANG Zhangsheng;XIE Lijin;GUAN Lixin(Science and Technology College Gannan Normal University,Ganzhou 341000,China;College of Physics and Electronics Information,Gannan Normal University,Ganzhou 341000,China;College of Information and Navigation,Air Force Engineering University,Xi’an 711000,China)

机构地区：[1]赣南师范大学科技学院,江西赣州341000 [2]赣南师范大学物理与电子信息学院,江西赣州341000 [3]空军工程大学信息与导航学院,陕西西安711000

出　　处：《现代电子技术》2022年第17期65-69,共5页Modern Electronics Technique

基　　金：国家自然科学基金资助项目(42061067)。

摘　　要：针对在低信噪比下卫星数字化视频广播第二代标准(DVB-S2)信号的调制类型识别问题,提出一种基于信噪比(SNR)估计的识别算法。通过提取卫星信号分别采用正交相移键控(QPSK)、八进制相位键控(8PSK)、十六进制绝对相位键控(16APSK)、三十二进制绝对相位键控(32APSK)调制时的分形盒维数、幅度特征参数及四次方谱特征参数作为判别信号调制类型的特征参数,并根据上述特征参数与SNR的关系,在不同信噪比下设定不同的判决门限值,提升了算法在低信噪比情况下的识别正确率。文中给出了识别算法的判别流程以及判别门限值的选取方法。通过仿真验证表明,所提算法在信噪比大于4 dB的情况下,调制类型识别正确率可达到96%以上,实现了在低信噪比下对DVB-S2信号的调制类型识别。In allusion to the modulation type recognition of DVB-S2 signal at low SNR,a recognition algorithm based on SNR estimation is proposed in this paper.In the algorithm,by extracting the satellite signals,the fractal box dimension,amplitude feature parameter and quartic power spectrum feature parameter of DVB-S2 signal are taken as feature parameters for distinguishing the types of signal modulation when QPSK,8PSK,16APSK and 32APSK are adopted respectively for signal modulation.According to the relationship between the above features and SNR,the different threshold values are set at different SNRs,which can improve the correct recognition probability of the algorithm under the condition of low SNR.The discrimination flow of the recognition algorithm and the method of selecting the threshold value are presented in this paper.The results of the simulation experiment show that the correct rate of modulation type recognition of this algorithm can reach 96% when the SNR is greater than 4 dB,which realizes the modulation type recognition of DVB-S2 signal at low SNR.

关 键 词：DVB-S2信号 调制类型识别 SNR估计 低信噪比 判别门限 四次方谱 分形维数 

分 类 号：TN927.2-34[电子电信—通信与信息系统]