摘要
为了快速自动识别低信噪比下的数字幅度调制进制,提出了一种识别M进制正交幅度调制(M-QAM)和M进制幅度键控(M-A SK)的调制进制的方法。该方法利用优化的缩放尺度对信号进行小波变换,以识别M-QAM和M-A SK信号的调制进制,并进行了仿真。仿真结果表明:仅利用100个观测符号,当信噪比大于或等于-4 dB时,M-QAM信号的正确识别率大于93%;当信噪比大于或等于-10 dB时,M-A SK信号的正确识别率大于90%。这说明该方法在低信噪比下能够快速获得很好的识别性能。
A method to identify the modulation levels of M-ary Quadrature Amplitude Modulation （M-QAM） and M-ary Amplitude shift keying （M-ASK） was developed to rapidly and automatically identify the modulation levels of digitally modulated signals at low signal-to-noise ratios （SNR）. The method uses wavelet transforms with the optimal scale to identify the modulation levels of the M-QAM and M-ASK signals. Simulation results show that when the SNR is not lower than -4 dB, the percentage of correct identification of M-QAM is higher than 93% and when the SNR is not lower than -10 dB, the percentage of correct identification of M-ASK is higher than 90%, using only 100 observed symbols. The results show that the method can rapidly acquire good performance at low SNR.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2006年第1期35-38,共4页
Journal of Tsinghua University(Science and Technology)
关键词
信号处理
调制识别
小波变换
signal processing
digital modulation
wavelet transform
