摘要
提出了一种识别方形QAM信号(4QAM、16QAM、64QAM和256QAM)的新方法,该方法将特征参数和信号降阶算法有效的结合。所选用的特征参数提取简单且易于实现,不受加性高斯噪声的影响;给出了该算法的理论推导,计算机仿真也表明该参数对滚降系数不敏感;选用的降阶方法不受载波相位的影响,较为实用。实验结果表明,该识别方法能够有效的识别方形QAM信号,4QAM、16QAM、64QAM和256QAM的识别率达到80%以上所需的信噪比分别为9dB、15dB、24dB和24dB。
A method to recognise the square QAM signals is proposed （4QAM, 16QAM, 64QAM and 256QAM） which contains the feature parameter selection and the demotion of the QAM signals＇ degrees. It proved this feature parameter is unacted on additive Gaussian noise in theory and isn＇ t sensitive to rolloff-factor of the pulse shaping filter in simulation experiments. Also the method of demotion selected is unacted on cartier phase＇ s influence. This method is experimentally approved effective in square QAM signals recognition. When the recognition ratio is larger than 80%, the SNR of 4QAM, 16QAM, 64QAM and 256QAM needs respectively 9dB, 15dB, 24dB and 24dB.
出处
《计算机工程与设计》
CSCD
北大核心
2009年第18期4155-4157,4187,共4页
Computer Engineering and Design
关键词
调制识别
方形QAM信号
特征参数
降阶算法
滚降系数
modulation recognition
square QAM signals
feature parameter
demotion
rolloff-factor
